IFATCA - The Controller - August 1976

D 21003 F

JOURNAL OF THE INTERNATIONAL FEDERATION OF Al R TRAFFIC CONTROLLERS ASSOC I A TI O NS

In this Issue:

Impressions from IFATCA's 1976 Lyon Conference Stresses of the Air Traffic Control Officer

FRAN KFU R T AM MAIN

AUGUST 19 76

VOLUME 1 5

N O. 3

SELENIA - AIRPORT AND AIR TRAFFIC CONTROL SYSTEMS ~~ INDUSTRIE E L ETT RONICHE ASSOC IATE S.p .A. CI V IL RADAR AND SYST EMS D I V ISION Via Tiburtina km 12.400 001 3 1 ROME I ta ly p 0 Box 7083 I 00100 ROME C~b.l es SE LEN I A ROMA Telex 6 1106 SE L ENIAT Phone (06)43601

112 Radar Systems now successfully in operation in 18 countries are the best evidence of the high quality standards and experience achieved

by SELENIA in the design, implementation and logistic support of A TC Radar Systems.

SE LEN IA offers advanced equipment for air traffic control including: Radars; Broad band and narrow band links; Digital displ ay subsystems; Computers; primary and secondary radar extractors; Simulators and digital interface eq uipment;

Au tomated airport subsystems; as well as comp lete ai rp ort t urn key projects, together with wide experience in system design, system implementation and integration . logist ic support .

IFATCA

JOURNAL

OF

AIR

TRAFFIC

CONTROL

THE CONTROLLER Frankfurt am Main, August 1976

Volume 15 ¡No. 3

Publisher: International Federation of Air Traffic Controllers' Associations, P. 0. B. 196, CH-1215 Geneva 15 Airport, Switzerland.

Officers of IFATCA: J-0. Monln, President, 0. H. J6nsson, Vice-President (Technical), H. H. Henschler, Vice-President (Professional), E. Bradshaw, VicePresident (Administration), T. H. Harrison, Executive Secretary, H. Wenger, Treasurer.

Editor: G. J. de Boer, P. 0. B. 8071, Edleen, Kempton Park, Tvl., 1625 South Africa, Telephone: 975-3521 Contributing Editor: V. O. Hopkin (Human Factors) Managing Editor: Horst Guddat, Otto-Bussmann-StraBe 7, 0-6368 Bad Vilbel 2, (Federal Republic of Germany).

Telephone: (06193) 85299 Publishing Company, Production, Subscription Service and Advertising Sales Office: Verlag W. Kramer & Co., Bornheimer Landwehr 57 a, 6 Frankfurt am Main 60, Phone 43 43 25 and 49 21 69, Frankfurter Bank, No. 3-03333-9. Rate Card Nr. 6.

Printed by: W. Kramer & Co., Bornheimer Landwehr 57 a, 6 Frankfurt am Main 60 (Federal Republic of Germany).

Subscription Rate: OM 6.- per annum for members of IFATCA; OM 10,- per annum for non-members (Postage will be charged extra) Contributors are expressing their personal points of view and opinions, which must not necessarily coincide with those of the International Federation of Air Traffic Controllers' Associations (IFATCA).

CONTENTS 6

IFATCA does not assume responsibility for statements made and opinions expressed, It does only accept responsibility for publishing these contributions.

The Provision and Use of Information on ATC Displays (II) The 1976 IFATCA Conference, Lyon, France

15

Contributions are welcome as are comments and criticism. No payment can be made for manuscripts submitted for publication in "The Controller". The Editor reserves the right to make any editorial changes in manuscripts, which he believes will improve the material without altering the Intended meaning.

Air Traffic Control In Sweden (Part II) .

21

International Law (Part X) .

26

ATC and the Aerial Photographer

27

Written permission by the Editor is necessary for reprinting any part of this Journal.

Spotlight on a Corporation Member Stansaab Elektronik AB

29

Cartoons: Helmut Elsner.

June 21 at J F K .

31

Future Air Traffic Control Systems (Ill)

34

Airports and their Control Towers (5) .

39

Stresses of the Air Traffic Control Officer

41

News from Corporation Members

44

Publications Review

47

Fotos: Archiv, Abrams Aerial Survey Corp., L. Allwin, Public Information Service Nicosia, Rockwell International, Stansaab Elektronik AB. Advertisers In this Issue: Selenia (inside cover), Hollandse Signaalapparaten (page 2), Racal Thermionic (page 5), International Aeradio Ltd. (page 7), Marconi Radar (page 9), Ferranti Digital Systems (page 24/25), CYATCA and IFATCA 77 (page 37), Stansaab Elektronik (back cover).

.

Rea~to

explore the horizons in ATC? ....

..............

--------------....

........~..,oOA.

~

',~

,

....".!f!ll

........

...................

',,

....

',,, ',..,

..... ._

-------------

Your range is 200 nautical miles Yiilh

LAR·ll SURVEILLANCE RADAR!

As air traffic gets more dense, control gets more tense. The better you can see, the better you can control. These are the facts of life for an air-traffic controller.

That's why LAR-11 ls such a welcome addition to existing conventional systems. And why ATC authorities are looking at II with such Interest.

LAR-11 ls a high-power, high-resolution L-band radar system able to scan more than 200 nautical miles out, 80 OOO feet up, with a resolution of 1.2 degrees In azimuth and 90 metres In range. Al the same time, It can operate efficiently at 0.5 aNmi

Partner in Philips-in-Aviation ... total capability from the ground up

In short, It gives you both air-route survelllance and terminal-area control with Just one radar system. And there's more.

Its transmitter uses pulse-compression

0.5Nmi

..........

................',' ' '

...........',,

----------------------=~

-

techniques. Its receiver gives optimum MTI (moving-target Indication) with minimum sensitivity to clutter. An Integral primary video extractor processes the Information to produce, along with a dedicated processor, a completely synthetic picture displayed on autonomous random-access graphic displays. This Is complete with digital map and all flight Information ••• and It's clearly vlslble In a daylight environ· men!.

The radar output Is exceptionally clean so video extractors and data handling systems will not become saturated.

Ready to explore the horizons In ATC? Send now for details.

Hollandse Slgnaalapparaten B.V. Telephone: (05400) 88111 P:o. Box 42 Hengelo (Ov.) The Netherlands

e 625-2

2

HOLLANDSE SIGNAALAPPARATEN

From The Tower ...

---'--

---'-Early Retirement: That Elusive Goal

The feeling on the part of controllers that it is unrealistic to believe that such a demanding profession can be performed until the normal Public Service retirement age of 60 or even 65 is one that has been with us for a very long time. These feelings crystallised into convictions in the late 1950s and early 1960s with the introduction of civil jet aircraft, the introduction of radar into the system, and the rapid expansion of the ATC system itself. It has been well-documented that the introduction of radar coupled with the doubling of aircraft operating speeds has transferred a large measure of responsibility from the pilot to the controller and added a great amount of pressure and stress to the controller's already heavy responsibilities. Years ago, two DC-3s in opposite directions had a closing speed of 260 knots, and there weren't very many of those, but times have changed and we can't help feeling, rightly or wrongly, that there is an unfortunate tendency in many national Aviation Administrations of failing to recognize some fundamental changes in the controller's profession. Efforts to promote a sense of urgency regarding our early retirement aims have not had much success so far apart from some isolated instances.

The increased stress and pressure in the late 1950s was one of the fa~tors leading to the formation not only of national controllers' associations but also of IFATCA, since there was no other way to bring to the fore nationally and internationally the controllers' special problems, nor to work toward their solution. After IFATCA's formation, the Federation asked for recognition of the problem of early retirement on a world-wide level, along with other urgent matters such as recognition of the controllers' profession and more realistic working conditions. o.ver the years, success in these fields has been disappointing, but surely, when we consider the controllers' case for early retirement, here is so obviously a matter which makes com~onsense. May be the following expose which we read recently in an Information Bu.lle~in of our Canadian Association will finally convince those in the higher echelons of Avi~tion Management that this question cannot be postponed any longer: . . Of considerable concern to the controller particularly as he grows older is the possibility of losing his ricence d ue to failure • O to passI the annual medical. Although not many cases h ave actually occurred . . .

• con t ro II ers are of the opinion that as the group grows older .inevitably fa'I1ures will · take place and the Air Traffic ' Control organisation and' other .t bimore medical . su1 a e organisations licences. may not always be able to absorb men who cannot retain their One of the prime reason d s a vanced b~ controllers for some kind of 'early retirement' was that they felt th t 10 slow down men~~ll ~~ before .they were in danger of failing the annual medical, they would were convinced th!t m~~e point where they would be unable to control traffic safely. They but under th .Y of the older men would eventually be 'carried' by younger men, · · th t e present c1rcumstan supervisors will su . . ces could see no alternatives. The time will come a 0 to occupy th 'h t PP rt this point of view and state that certain men are no longer expected Although th e process of ageing . · d as yet the e . o seats'. . of controllers .1s not fully explame • re 1s considerable sup rt . . profession'. po given to the viewpoint that A.T.C. is a 'young man s This slowing-down phen . · r · d"I omenon (real or imaginary) places the controller and his superv1so in .a rea 1 .1.emma · It is d'ff 1 icult for a supervisor to label as incompetent (for the most d eman d mg positions) some · one who has performed well in the past and who can still pe rt orm th e Iess demanding JO · b s now. Hence the development of the norm which · · requires t he young men to. carry the old er men. Unfortunately as the group grows older, more older . men will be earned and the gre at er th e demands on ' the younger men will · be. Some of the younger r:nen feel that these extra demands will make them 'burn out' at an even earlier date.

There 1s reason to b.elieve that the controller suffers the greatest pressure at the point where he has passed his peak performance. For a time his experience in controlling traffic,

3

i.e. knowing all the tricks of the trade, compensates for the fact that he is starting to slow down but at some point he is beginning to realise that, compared to his younger days, he . ¡ finds •the work increasingly difficult For a further period of time, he can h"d 1 e h"is c oncerns . from his friends and his supervisor, since the problem will arise only during the busi~st periods in the shift. At some point they will observe from his behaviour tha! he is ~~vmg some difficulty, e. g. a tendency to avoid the 'hot seat', hesitancy in making dec1s1o~s, perhaps increasing irritability and physical signs of increasing efforts, such as excessive perspiration, delays in responding to transmissions from pilots, etc. Few of us a_re able to visualise continuing active control of aircraft after the age of 45 to 50. In fact, m Canada most men now employed who are over 50 years of age are placed in quiet sectors.

A major concern of controllers is their fear of being forced out of Air Traffic Control with no prospect of maintaining an income which would allow them to retain the standard of living to which they have become accustomed. This fear is based on two factors: a) The belief that as the controllers grow older they are less able to meet the job requirements in high traffic density facilities; and b) the belief that they will suffer significant income loss because their specialised training and experience will not readily lend themselves to suitable alternate employment.

It is clear that an early retirement program is necessary for operational air traffic controllers. Such a program should be designed to assist them in planning to leave well before the age of 60. The policy on exit from Air Traffic Control should be rooted in the concept that the profession is a 'young man's job' and that management should not continue to presume that controllers can actively control traffic up to age 60, let alone 65. Moreover, findings indicate that one should not expect to perform effectively as an air traffic controller until age 60/65. These findings are further complicated by the fact that one may be forced out of operational ATC because of an inability to meet the medical standards for licence renewal at a much earlier age than normal retirement age."

Therefore, it can be concluded that pension considerations beyond those available to the average public servant will be necessary. Aviation Administrators, please note, in the overriding interest of air safety.

Sir Donald Anderson The Federation has learnt with regret of the recent death of Sir Donald Anderson, the former chairman of Qantas. Sir Donald, who started out as an air traffic controller and who was the first secretary of our Australian Member Association, was appointed Auslratta's DirectorGeneral of civil aviation in 1956 at the age of 39; he held the post until 1973, when he became chairman of.. Qantas, retiring in July 1975 because of ill-health. In 1948 Sir Donald chaired the ICAO panel which established the principles of modern Air Traffic Control standards, and over the years he became well known in international aviation affairs.

IFATCA members will remember Sir Donald from our Federation's 1975 Conference in Melbourne, where we were privileged to meet him. The Conference was obviously an occasion which also greatly appealed to Sir Donald, and he seemed thoroughly at home in the company of the world's controllers. The Federation has lost a staunch supporter who fully played his part in helping the Australian Association make IFATCA '75 the outstanding success it was.

A Call To Support IFATCA, The Controller's World Organisation Mr. R. F. Alexander, President, Civil Air Operations Officers' Association of Australia, writes as follows in his Association's Newsletter: "I reaffirm our support of IFATCA's alms ~nd objectives. Its technical contributions to air safety are, without doubt, becoming increasingly recognised. It must have been evident, particularly to those members who attended committees A and cat IFATCA's 1975 Conference in Melbourne, that there are controllers In many parts of the world who are badly In need of assistance in many forms.

We, in Australia, who enjoy facilities and working conditions better than most, can help our less fortunate colleagues by strongly supporting the world organisation which, despite a restrictive financial situation, manages to provide some guidance toward improving their Jot. Surely, in an industry as truly global as aviation, it Is in our own Interest to concern ourselves with the welfare of our International colleagues."

The Controller's Legal Liability (Part Ill)

by A. Avgoustis, LL. B. Due to circumstances beyond our control, the third and final article in this interesting series will now be published in our November 1976 edition.

GdB

4

Racal~hermionic's multi-channel International Communications Recorder a!Yay1 gets the message.

And unlike most humans, it's ever ready to find fault with its~lf. In fact, It was created to meet the exceptionally e xacting requirements of airport authorities -and is In very widespread use all over the world. .

The reliability of this superb machine Is JUSt about total.

There is a1Yay1 a spare track available, should the track fail while recording. The back-up system precisely duplicates the master. and is ready at any Instant to take over. Further, Iffor any r~on the ICR should not have its operating tape

replaced after 24 hours, the back-up would continue for a further entire day, switching on an automatic warning system to indicate the need for replacement.

24.hours a day 365 days a year; the ICR trustily records the voices of time. Engineered to the highest perfection, ~e ICR can also, if desired, keep meticulous record of the time when events occurred.

Standing under 2 metres high, the Racal~hermionic ICR packs astonishing technical achievement into its solid fra~e. It has serious work to do. Critical, responsible work.

Which It will always perform perfectly. ¡

R

Thermionic Limited

1 H~~ley Industrial Estate Hythe. Southampton Hampshire. 804 5 z H Tel: Southampton (0703) 843265 Telex: 847667

Racal¡Thermionic the recording people

IiISSBIJ The E/eetTOl1lcs Group

5

1 I'

!:

The Provision And Use Of Information On Air Traffic Control Displays (II)

by V. David Hopkin, R.A.F. Institute of Aviation Medicine, Farnborough •. U. K.

The first part of this paper (published in the May Issue) noted that several kinds of mismatch can occur at the man· machine interface in Air Traffic Control systems. The procedures which should be followed in designing tasks for .new Air Traffic Control systems were described, starting from the stated purpose of the system, considering the definition of tasks and the grouping of tasks into Jobs, and discussing the retention of existing skills and established traditions in new systems. The stages in the design of the individual's workspace were described, from the broad principles of the phy· sical environment to the details of specific items of equipment. Mistakes in design occur if procedures are omitted and some mistakes are predictable but not recognised in advance. .

A variety of evaluation procedures can be applied to a system as It evolves. These include simulation, field studies and various descriptive techniques. Evaluations may show that the necessary Information for a task is not present or that the information is present but not in a usable form. The second part of the paper discusses known human limitations to which equipment, and particularly computer aids, must be adapted to ensure an efficient man-machine interface which achieves its intended efficiency and enables the man's abilities to be used to the full.

Human Limitations Sensory Capacities Enough is now known about man's sensory capacities to make it relatively straightforward to adjust equipment to them. The limitations on man's information processing also are becoming sufficiently clear to prevent them being ·1n advertently exceeded in task designs. On . the whole, the peed with which a man will perform various tasks can be s edicted quite well. The kinds of error which a man typiP:lly makes are also known, as is their relationship to task, sensory channel, and to information coding. For example, gouidelines can be formulated to mtnimise auditory mishearings (8).

~

Mishearings can be classified in various ways. From the known distortions of a particular R/T channel or telephone communications system, the mishearings which may occur when the system is in use can be inferred. By selecting appropriate wordings, message formats and phonetic sounds, precautions may be taken to cancel potential error sources. Practical steps, such as the evolution of the ICAO alphabet, minimise and compensate for known or predictable sources of error and misinterpretation in auditory messages.

In vision too it is generally possible to design displays to fit man's capacities. The relevant factors are known. They include knowledge of the minimum eyesight requirements of the operators, of viewing distances and angles of the d' plays, of the relative visibilities of various information isdings of the legibility of letters in relation to their height, design and grouping, of display illuminat .ion, of ambient illumination, of the reflectance values for surfaces, and so on. Careful measure~ent of all the relet factors permits a correct deduction to be made on · ·mf ormat'ion w1·11 be read van displayed alphanumeric h th w e er d. · b d th able or not, and also enables pre 1ct.1ons to e ma e o~ e f the errors which are most likely to occur, provided ·11 b . fl d I b nature o it is acknowledged that these w1 e m uence a so y other factors, such as the nature of the task a~d !he exof the operators. Usually the nature,. incidence, . penence causes, and cures of probable errors can be discovered.

~~dth, ~ontrast,

6

Higher Order Functions Although relatively reliable data exist about man's sensory capacities so that information displays may often be adequately designed on the basis of current knowledge, comparable reliable data on higher order functions, such as perceptual judgement, problem solving and decision making, either do not exist or are neglected. As a result, mismatches between man and machine occur in association with these functions in a way in which they do not occur in relation to sensory capacities, because for these functions the assumption has commonly remained unchallenged that it is sufficient to present the information known to be necessary for a task rather than to verify that it is usable.

This distinction may be illustrated and clarified by an example from a context in which human limitations have been recognised to some extent. In this example, there is no doubt that all the necessary information is present, an~ it is acknowledged that the man may not be able to use it fully. Manual conflict detection requires the controller to pick out from all the information on his radar display pairs of tracks on potential collision courses. To do this h~ needs to know their present positions, their headings, their heights, their relative and absolute speeds, and any changes in height, speed or heading which will occur before the intersection point of their tracks is reached. All this information is available to the controller, either directly on the radar display or on an electronic data display or on flight strips, or indirectly by being obtainable on call-down from the computer, or from the pilot on verbal request.

Sometimes all the relevant information may be on the rad~r display itself. It is impossible to train anyone to use this information to detect consistently every conflict that occurs however dense the traffic becomes. No matter how much training the man receives or how able he is, he can never become infallible in performing such a task because 1 innate limitations in his capacity to make accurate, rapid and frequent perceptual judgements.

As traffic becomes dense, further limitations are encountered, associated with the rate at which he can search.

Searching for pairs of aircraft in potential conflict situations requires a continuous effort of concentration which the ~an cannot sustain for a task so intrinsically tedious. Searching

?

The bird selects its flight path, its speed, its height. Free to climb and descend as it pleases. Not so the aircraft pilot. He has to proceed in busy air lanes in a disciplined manner. For the safety of his aircraft and passengers he must have information enabling him to operate within accurate and precise limits.

From take-off to landing he has to rely on beacons, communications control systems and other navigational aids to

,-m

I I I

"-

lliTERllAT/OflAL AERADIO LIMITED -

supplement his own expertise. Like the low cost. rugged and reliable range of equipment provided by IAL. Designed for a number of applications with reliability as a major factor. Products resulting from over twenty-five years experience and expertise in the aviation business.

Experience, expertise, reliability- that's IAL.

'

Please send me further information Name co_m _ -'pa_n~y~~~~~~~~~~~

II

_,

_A_dd_r_e_ss~~~~~~~~~~~- 1

Equipment Division International Aeradio Limited, Aeradio House, Hayes Road, Southall, Middlesex, England.

Telephone: 01-574 2411 Telex: 24114

7

has to be conducted by examining pairs of aircraft sequentially and taking a separate decision about each pair. When traffic is dense there are many aircraft pairs and searching is very time consuming. Searching also tends to be incomplete. Aircraft within the same group or cluster tend to be compared with each other more readily than pairs of aircraft belonging to separate clusters. Some potential conflicts may therefore be missed, particularly if they are associated with certain traffic configurations or with certain angles of approach. Human search patterns are never fully efficient, even if they have been improved by training or by some form of enforced scanning pattern. It takes so long for a man to examine m~ny pairs _of aircraft that co~­ flicts may develop while he 1s searching elsewhere. It 1s impossible to prove that certain aircraft are not being consistently omitted altogether from the search task.

To put this example in its correct perspective, it is not suggested that numerous conflicts have in the past remained undetected because of man's limitations. On the contrary, the system is designed to min~mi~~ the need for search tasks, and the workload of the md1v1dual controller is adjusted so that the remaining search tasks can be conducted to acceptable operation.al. st~ndar~s of saf~ty, but th resence of major human hm1tat1ons m comparison to of machines means that conflict. detection is one of the functions where benefits are most likely to accru~ from au t omat .10 n . While it is a manual task, the . . problem 1s not the provision of information but the ab1hty of the man to

th~s~

use it.

Dlscernable Differences A further limitation in human abilities can be illustrated by the same basic example. Ju_dgements have to be ~ade of relative aircraft speeds. Airspeeds may be d~p1cted · 11 yo n associated displays numenca . such as . electronic data · 1ays, b ut they are often not included m the label on. a d1sp radar d .1sp1ay because this would . . lead to .labels of excessive . . d omplexity. The main mformat1on on the relative size an c . d . th . d . t" · craft may be contame m . e1r epic ion on spee d s o f air . the ra d ar d 1splay• but not in a . form which can be.. used. . 11 y, a l"ne is drawn showing Typ1ca 1 . .the current . pos1t1on of ft , •ts . the aircra 1 speed and its heading. The line may. be a "tail" from its present position showing where the aircraft r in a predictive display be drawn ahead of its has b een, o h · ft · i I presen t pos1•t·ion to show where t e . a1rcra 1s go ng. n . either case s peed is proportional . to lme length . so that . . the . lengths show relative speeds.

Heading 1s given relative 1me . by the orientation of the line on the display. . quite small Th e p1·1ot can report or be instructed to make d . spee d ch a nges · The computer can store an use mforma.

Relation on spe eds • speed changes and . rate. of changes. . . t1vely sma II d"ifferences in these d1mens1ons can . influence computer- b as ed decisions · and some of these differences . .m spee d are so small that they are not detectable . directly •m v1sua • 1 t erm s on the radar display where a considerable . before the Imes are difference ·in 1·1ne lengths has to occur • .

1f they are some re I.1abi y repo rted as different, particularly . . rt A large difference m the length . d1stance apa . . of an ex1st•mg 1•me h as to appear before it becomes obvious. from the length of the line alone that the speed of an a1rcra~ has ch ange d , esp ec ·ially if the judgement . has to be made m absolute terms because no other aircraft ar~ nearby. If the length of a line is increasing or d~creasmg t~e rates at h'ch the speed changes are occurring can be Judged only approximately indeed from the lines. Changes in the

:e~ 8

rates at which these speed changes are occurring have to be gross before they become noticeable at all.

Information in these visual terms can be presented on the display in a subtle form and in full detail within the constraints imposed by the computer, by the software and by characteristics of the display generation. However, much of this information, if presented in the form of line lengths, cannot be used by even the most trained man because he simply cannot detect small changes in speed, moderate changes in relative speed, large changes in absolute speed, or gross changes in the rates at which speeds are changing.

In addition, there are serious limitations in the pace ~t which he can make even the limited judgements which his abilities allow. He must look continuously for a long time at a track before he can spot an increase or a decrease 1·n the rate at which a change in speed is occurring. If such a . ·11 task is required of him operationally, a task analysis wa indicate that the information must be presented to him in 8 totally different form, using different coding conventions t~ indicate changes which are below his visual threshold, if he ls to perform the task to an operationally acceptable standard. In practice this may be done by converting the information to alphanumeric form and by introducing other coding conventions known to be more effective in conveying rate information or changes in rate information clearly to him.

If the man's task is relatively simple, the principles for designing it are usually well defined and orthodox. Data entry tasks, for instance, using a conventional keyboard can be designed efficiently by combining a knowledge of task requirements, of the common sequences and orders of expected key pressings, of the lateral and horizontal spacings recommended for keys, of the optimum positioning of a keyboard in a workshelf, of the principles of the layout of workspace, and of-the physical environment. As long as the tasks are routine and can be clearly described, the steps required to optimise their performance can be stated. Comparable evidence on tasks involving higher mental functions is relatively sparse and less definitive, and the little available is not sufficiently well known or accepted to have much influence on workspace design.

Adaptation to Changes Human limitations are encountered in the number of independent sources of Information from which an operator can collate relevant data. Far more sources can be provided than can be effectively used. Compared with t~e mathematical optimum, human decision making has certain typical weaknesses: a tendency to be influenced unduly by the most recent data; and a reluctance to modify a previous decision when confronted with contradictory evidence. Instructions about strategies and about the weighing of different sources of information, even when they are clearly expressed, may prove to be impossible for the man to follow because of his innate limitations, and he has a propensity to continue to solve problems by his traditional favoured methods long after they have ceased to be appropriate, especially if his attention is never drawn to revised and improved procedures. These typical human characteristics appear to have little influence on current designs or on proposals for displays in future Air Traffic Control systems, and in some cases the potential importance of these characteristics remains to be established. But there is no doubt that the capacity of the system to provide information greatly exceeds the man's ability to process it.

alpha bata eamma dalta Complete data processing systems to enhance existing radar All the information required for control with safety and accuracy in the most complex air trattic situations 1s contained in a raw rada r display.

The latest Marconi data processing systems will extract this information and present it to the controller in a simple. accurate. and easy-to-use form.

cc = rnw radar -approach/ TMA/ en¡ route II = raw primary and extracted SSR. plus optional tracking - terminal area/ approach con trol y =extracted primary and extracted SSR, plus optiona l tracking basic en-route system (area control centre) ll = extracted primary and extracted SSR with tracking and flight plan processing-advanced en-route system (area control centre)

9

Changes either in information content or in the ways the label either in a form directly compatible with verbal in which information has to be collated may alter the opti- messages. such as a call sign, or in a form more directly mum strategies for performing a task. When display chan- compatible with the automated system, such as a code; but ges are proposed for technical reasons, such consequen- the consequences for the controller in terms of data collatces may be discounted or remain unrecognised. Many ma- ion and cross-referencing are quite different, depending on jor changes have already occurred in the information dis- the choice made. Often height information is provided on the label, perhaps only by a simple symbol to indicate that played to controllers and in the design of their workspace.

Further major changes can be envisaged in the future, in- an aircraft is climbing or descending. When height is provided digitally. the controller's task is affected a great de~I cluding dispensing with flight strips. Sometimes attempts by the proportion of aircraft on the display for which this are made to automate existing display formats as they digital height information is available. If few aircraft are stand. Automated flight strip boards may replace flight transponding height information, the need to refer these strips, and their content and format may replicate flight heights to the height information about other aircraft, which strips so well that few associated consequences for task is displayed elsewhere, may involve so much work that it is performance occur. Transferring flight strip information simpler to ignore the limited height information on the radar onto electronically generated tabular displays modifies displays and to reach all decisions affecting height using content and format somewhat more, and renders some information on flight strips or on electronic data displays. comparisons and collations of data more easy and others more difficult. Introducing a dynamic format for these If all aircraft, or almost all aircraft, are transpondinQ electronically generated displays may well imply a need to height information, then height separations can be achieved modify strategies if the advantages of the dynamic format by using almost exclusively the height information on labels are to be fully realised. Often, however, the necessary foron the radar display. A change of tactics may occur. Formal or informal instructions and re-training are not given, merly, with no height information on the radar display. separations between aircraft would tend to be achieved with the result that new displays may never be used to full advantage as intended, or if they eventually are, the proinitially by plan information on the radar display, and incess is a gradual one of discovery by the controller. The structions to aircraft would tend to be heading or speed argument is not that display formats should remain unchanges. Reference would only be made to height inforchanged when automation is introduced, but that the benemation, which must be obtained from flight strips fits of changes may fail to materialise if the display changes or from other displays, if difficulties were encounare provided without suitable guidance on their usage. tered in maintaining separation in plan. By contrast, if Even for automated displays which are superficially accurate height information appears for each aircraft on similar to the manual ones which they replace, associated a label on the radar display in more precise form than changes in procedures may be necessary to obtain a satisheading or speed information, the most efficient tactic infactory match between the provision of the new information volving least collation of information by the controller maY and its correct use. This point becomes more obvious if then be to maintain aircraft separations primarily by height. new displays do not directly supersede existing ones but and to resort to heading and speed changes only when introduce new principles, rendering some former tasks difficulties are encountered in maintaining separations unnecessary but often bringing -new¡ tasks as well. The between adjacent aircraft by height alone. This change of replacement of simple secondary surveillance radar codes tactics would increase the proportion of instructions to airwith progressively more elaborate labels for each track on craft referring to requested height changes. Solutions to the radar display introduces profound changes in the pri- impending conflicts may therefore be considerably influenmacy of various information sources and in the techniques ced by the ways in which information is provided. It follows which are appropriate for using them. The new displays that different errors may also occur. Changes in displayed may be a deliberate attempt to change information handling information imply that new precautions may be needed to procedures. For example, an intended consequence of prevent errors of a relatively unfamiliar kind. labels on radar displays may be the reduction of verbal R/T Between these conditions of few aircraft transpondin9 messages between air and ground. If this attempt is height information and most transponding it - conditions successful, the associated procedures for collating and which call for different procedures by the controller - there handling information must change, as visual data replace will be a point at which the proportion of fitted aircraft has verbal data. Commonly, however, specifications for desirbecome sufficient for revised tactics to be adopted. This able changes in procedures are not drawn up in advance, will depend on individual judgements and preferences, as but these changes are allowed to develop in an empirical will the extent to which tactics are revised. In terms of way when the new system is first tried. Inevitably, the modi- efficiency it should be possible to define the point at which fied procedures may under such circumstances bear a a change in tactics would be beneficial, but the impression closer resemblance than they should to those which they is gained that Individual controllers follow their own preferences. Although, whenever possible, it is sensible to leave supersede. such decision making to controllers themselves, it is no longer sensible to do so when the decision making is not Effects of Information on Tactics on a fully informed basis. The process of fully informing the Decisions on the size, format and content of labels for controller should lead to a clear estimate of where, if at ¡ dividual aircraft on radar displays depend more on the all, the optimum proportion for a change of tactics lies. ~rovision of inf~rmation than on its predicted use. Often ater emphasis seems to be placed on factors such as ~:~el size, label overlap and visual clutter, than on the Memory and Attention In earlier systems the controller amended flight strips by ed requirements of the controller's tasks. Label cond e d uc f h . I hand, and had to remember a verbal message correctly, or tent is also of course dependent on the state o t~c mca jot it down as he received it, in order to do so. Because development and on costs. Identity may be provided on

10

the task design itself demanded this memorising for a short time and also required an action in the form of writing down on the flight strip the amendment which had been remembered, the controller was able to recall some of the information he needed to maintain separations because his task required him to remember it and take some action on it. With transponded, automatically updated information, the controller has not had to remember it nor has he had to perform any action using it. Changes in procedures have thus affected what the controller remembers. Because of this, future displays must act as a memory aid, although previous ones did not. Future displays may also have to draw the controller's attention to information which formerly would have been transmitted through him but which can in future be amended or updated without his participation.

Thus information on future displays has to be provided in a form which will fulfil these additional functions of memory and attention.

Although a task description may reveal that the same information as before still has to be provided, the uses to which the information will be put have changed, and therefore the formats for the information, and perhaps the coding of the information, also needs changing. If strict comparisons are made between the man and machine solely in terms of the information needed for the task, no differences may emerge because the basic function to be fulfilled in the system has not been altered. However, at the manmachine interface, changes in the machine imply changes in the man's tasks in order to fulfil the same function; these consequent changes may not be immediately apparent if they refer to the gathering and assessment of information, the relative role of human memory, and the replacement of active tasks by relatively passive ones.

Certain human limitations may go unrecognised if it is assumed, without a detailed check on the implications for th~ associated jobs, that an automated process can fulfil an existing manual function. In particular, it is difficult to inclu.de qualitative information, and information which has · d gements and experience, . as distinct frelied . on hu man JU r~m information which is in digital form. As a general ~nnciple it should be assumed that no function can ever d er~utomated in its entirety exactly as it stands without e 1 0.rately or inadvertently altering the controller's tasks . . associated with 't 1 • an d particularly higher mental functions re Iated to problem I . d . . tion a . ~o vmg, ec1s1on making, memory, atten.' nd mformat1on handling capacity. Although it is cl~1med that the introduction of changes is intended to re~1eve controller workload, and relatively direct and system orientated measures can easily . demonstrate that this ob . .

1ec~1ve has been achieved, extra tasks often materialis~ an ' even when the necessary information to do them is present, the necess ary system mod1f1cat1ons, .. . d' especially 1 isp ~ changes, to permit them to be done as well as poss1 e have often not been carried out.

Thought Processes it hOn: issue which has not been settled in ATC although the subject of some discussion and s~udy 1 controll s ednormal thought processes of the working cont f~r, ~n the adaptation of display formats and contents 0 it his thought processes. Display formats are based partly on traditional methods and partly on the technical · demands of . the equ1pment.

Often knowledge of how the man use~ information, as distinct from what information is needed, is not adequate to influence display formats. It is

cer~s t~en

not known how important it is to match displays to thought processes or, alternatively, to try to modify thought processes in order to match displays. Discrepancies between the provision and use of information on displays often arise from mismatches of this kind.

Scanning Lists Sometimes proposed displays clearly encounter restrictions in their usefulness caused by human limitations.

Inevitably from the nature of traffic, of electronic displays, and of ATC tasks, there is a continuing tendency to provide information in the form of tabular lists, in which items may be classified in many ways. These include the separation of east-bound and west-bound traffic, tabulation by height, by route, by reporting point, by sequence in the flow of traffic, by sector or other division of air space, by aircraft type, destination or speed, by main or alternate tracks, by the controller performing the task, and so on. Because any list may follow only a single convention, for other tasks using the tabular information, the data will not be listed in the optimum order. Therefore the controller will have to scan the list to perform some functions which differ greatly from that which determined the order of aircraft in the list, to the extent that finding the information he needs may become almost a random process. This may itself be acceptable when traffic is light, but when it becomes heavy a major scanning task is imposed just when he has no time to spare for it.

This problem is aggravated in an automated or computer-assisted context because the passive nature of the man's work means that more information must be gathered by scanning, since less will be remembered. The scanning which has been introduced does not match human limitations, and is less efficient the more it is needed. The information the man wants is provided, but not in a form in which he can use it efficiently. To use it fully, such scanning tasks should be avoided in the system design and, if they cannot be, the retrieval of the necessary information should be done automatically.

Similar points can be made about monitoring tasks where the passive viewing of displays to detect situations requiring intervention is a task which people cannot do well because they find it boring and tedious, and because atte~­ tion cannot be maintained for long on information which is not dynamic and inter-active. Therefore, as tar as possible, monitoring functions should also be designed out of the system or done automatically.

Knowledge of Options A discrepancy between the information provided and the information used occurs in modern systems which contain more information than can be assimilated or displayed.

If all the information were displayed, there would be far too much both to scan and to understand. A common flaw in sytsem design is to replicate the same information on different displays while retaining slight discrepancies between them. As a result, information on a radar display, on an electronic data display, on a data input device, on flight strips, and on a TV display, may be puzzling because it is derived from sources with different levels of accuracy, different reliability and different frequencies of updating.

When there is more information in the system than can be presented, some of which is needed for certain functions, two kinds of problem arise. One. the more straight-

11

forward, is how to depict called-down information. The second is how to inform the controller about what information is available on call down. Depiction problems are associated with providing a suitable display and with showing how the optional information relates to the information which is permanently displayed. The problems encountered are considerable, but essentially similar to those encountered in designing other displays. However, the problems in informing the controller about optional information are more recalcitrant. If he does not know that information is available or if he does not know how to retrieve what is available, then he cannot use it, no matter how relevant or important it is. Ideally, the system itself should inform him or remind him through the permanent displays of the existence of further potential relevant information, but this is difficult to achieve and also implies that the potential relevance of information can be determined by the system rather than by the man. Reliance must be placed on instructing the man about the additional information sources and on his ability to recall their efficient use. He thus must acquire considerable knowledge about the software of the system, and a fairly elaborate keyboard may be needed to let him select what he wants. The central point is that a discrepancy between providing and using information occurs when potential information is available, and means must be found to inform the controller of its nature and of how to retrieve it.

When automated aids are applied to decision making functions, a common solution is to display to the controller what the proposed automated solution is. This is relatively straightforward as is the provision of a means whereby he can accept or reject it. However, in order to decide whether to accept it or reject it, he needs to know how the solution has been formulated, and in particular which factors have been taken into account and which have not. Information about this, which is vital if his role is to be matched successfully with that of the system, -.Js very difficult to provide on displays and recourse must again be made to instructions and memory. The controller may have difficulty afterwards in remembering an automated solution, and receives tittle guidance from the system on which factors have already influenced the original automated decision.

The general theme appears to emerge that, in depicting displays for controllers to use, too much emphasis has been placed on ensuring that the information which is necessary for each task appears on the display and too little attention has been paid to the consequences for the an's memory of the display changes introduced. It is not ~nough to provide information or to provide a means of access to information. The displays should be used to assist the man's memory, to direct his attention to what is most important, to minimise search and monitoring, and to match his abilities.

Effects of Technical Changes In considering the provision and use of information, three further distinctions may be drawn. Firstly, information may be provided which simply cannot be used. Deficiencies in its depiction may render it unintelligible, or instructions for its interpretation may not be clear enough. It may have no self-evident meaning or it may impose excessive demands of search, monitoring, memory, collation or retrieval. In all cases the consequence is that information is not used and might as well not be there.

12

Secondly, information may not be in its optimum form because it has to be adapted to technical changes. Perhaps the simplest example of this concerns single colour flight strips. Other examples relate to clutter from labels, to limitations on coding available, to limitations caused, for example, by generating alphanumerics from a limited matrix, and to limitations caused by a precipitate application of new display technology.

Thirdly, discrepancies between the provision and use of information occur when new methods of portrayal, hailed as technical advances, are found to have no tangible benefits. Much of the current pre-occupation with colour displays demonstrates this point. The reason why colour displays are being provided at the present time refers to the state of technology and not to the state of Air Traffic Control or to the needs of the controller. Colour may bring advantages, but none of them seems especially urgent now. Therefore, colour may be provided in the expectation that it will be beneficial, but may prove to be no better than alternative monochrome codings to convey the same information. It may indeed have certain disadvantages associated, for example, with perceiving all information in a single colour as related, so that comparisons across colours are neglected (9). This is not to deny that people may prefer colour or that preferences may themselves be an adequate reason for having colour, but colour should not be rationalised as a system benefit nor claimed to have great advantages as a display coding, when the effects of its introduction may not always be to the advantage of the tasks being performed.

Trustworthiness of Information Another aspect of information displays affecting their use is the quality of information, including its accuracy. It is not apparent from looking at an air traffic controller's display what the quality of the information on it is. How accurately are aircraft positions shown? On what basis is information updated? How consistent is the information?

What sort of errors occur before the controller's attention is drawn to them? How large a change has to take place before it is displayed? Do the displays match the accuracy of the navigational information in the system?

Ideally displays should include some guidance on the quality of the information on them. In ATC, the controller's interpretation of the displays and his assessment of their usefulness depend on how far he trusts them and how accurate he believes them to be. The information depicted is quantitative but its use depends on his qualitative judgements. More qualitative information should appear on the displays themselves. Automation is associated with the transformation of probabilistic qualitative information into all-or-none quantitative information. As a consequence, the performance of certain tasks may be degraded. Quantitative information is presented as fact, and may give a spurious impression of accuracy and reliability. A single failure of quantitative information may reduce trust in it so much that reliance is no longer placed on it and it is seldom used. Reduced separation standards imply enhanced quality of navigational information, but displays fail to show how much the accuracy and reliability of the information have been enhanced. The mere provision of factual information may be insufficient to ensure its correct usage, in the absence of any indication of its quality and trustworthiness.

Timing of Changes If the man is to make the best use of displayed information, the initial introduction of any information on the display, and any subsequent amendments to it including its deletion, should occur at the optimum time in relation to the man's tasks. Otten information is updated automatically regardless of the man's needs. Often it does not appear soon enough. Sometimes it continues to appear when it is no longer of any use to him. The principles for timing the introduction of and amendments to information have generally been determined by technical factors rather than by the needs of the man doing the task.

Predictive Displays Some difficulties occur in matching the depiction of predictive information on ATC displays with human abilities.

Prediction may relate to future tracks, to future safety margins and separations, to future conflicts, or to future traffic flows. Problems arise in deciding whether predictive information should be shown, what form it should take, how far ahead it should extend, and how the inevitable inaccuracies which affect predictive information should be depicted. It may be possible either to depict on the display itself the expected accuracy in the form of the tolerance to which the computer is working, or not to depict this at all, but to leave the man to judge for himself. The controller's trust in what is portrayed will determine to a considerable extent how he is prepared to use the predictive aid, and its value can be negated if it is ever seen to fail. The basis on which the predictions are made must again be conveyed to the controller so that he can match his abilities with those of the computer and can judge whether a computer prediction should be accepted, modified or rejected. Generally it is considered that the problem has been solved by success in depicting the predicted information, without due consideration of how It is meant to be used and how the man's skills may be adapted to it.

In some circumstances it may not be possible for the computer to give a prediction, to provide a safety margin, or to resolve a conflict. The task must then be done manually. A mismatch between man and machine occurs if the information provided to the man merely states the failure of the prediction aid to find a solution without giving the reasons, but the reasons themselves may be very difficult to depict on a display in any way that the man can successfully interpret, since they are not originally in display terms and may be very complex. If many factors are included in the computer decision there is therefore a considerable difficulty in providing the reasons on the display for a particular computer recommendation or failure. Yet these reasons are essential for an efficient system.

Concepts of Safety Finally a disparity between the provision and use of information may occur when a problem is resolved by a displayed automated solution which is in fact safe but which for some reason the man does not consider to be optimum.

For example if there is a 15 mile gap between two aircraft and another' must pass between¡ them, the controller's inclination, other things being equal, is to route the aircraft equidistantly between the two to allow an extra safety margin lest any aircraft should behave unpredictably. However,

if a computer is programmed to ensure 5 mile separation standards, any solution within the central 5 to 10 mile gap is as good as any other, and the man may interpret the solution as less safe than it could have been. Therefore, a problem occurs because the display cannot give enough information on the detailed rules and algorithms being used, so that in a different form the same problem recurs of being unable to display directly to the man sufficient information to enable him to react in the most sensible way to what the computer is proposing. This problem of showing the rationale and the reasoning of the computer by means of the displays has still to be resolved satisfactorily, yet this kind of information must be conveyed more effectively than it is now, if future displays in Air Traffic Control are to be properly used.

Conclusions The main emphasis in the current approach to the design of displays in ATC is to provide the information which is deduced to be necessary to perform all the tasks specified for each working position. Sometimes the decision on what constitutes essential information rests on accepted procedures such as task analysis and sometimes it is deduced primarily from the known needs of existing systems. In translating these display needs into display hardware and software, the abilities and limitations of the users may be taken into consideration in the application of standard ergonomic principles for display design ~nd . workspace design, but often deficiencies in displays still arise because the basic human factors procedures have not been followed. Whether or not they are followed, a f~rther stage is necessary if displays are to be used as mt~n­ ded. This consists in ensuring that the nature, quantity, format and integration of displayed information mat~h the capacities of the user in the sense that the displays and their contents are optimised in relation to human abilities and limitations in their use, rather than merely optimised in their methods of portrayal. Bridging this gap between providing information and using it is a neglec~ed part of the process of matching the man and the machine within the system.

- In this paper many examples of discrepancies between information provision and use have been mentioned. It is apparent that the causes of these discrepancies are numerous and varied. Occasionally no satisfactory solution is possible and the human limitations may have to be accepted as limits on the system efficiency if it is not possible to redesign the system to circumvent them. More commonly, specialist human factors advice on the portrayal of Air Traffic Control information has not been sought or has not been followed.

Some problems arise because there is an implicit assumption that if a display represents a technological breakthrough It must have human factors advantages also.

Enough exceptions to this contention have appeared already to suggest that it cannot be adopted as a guiding principle. Display techniques which are novel are more likely to embody human factors limitations that only become apparent at a relatively late stage in the evolution of the system. Evaluations of display innovations may measure most carefully those features of the system which are enhanced by the innovation and fail to measure with corresponding thoroughness other features which are degraded by It. Biased and overoptimistic estimates may then be

13

made on the advantages which will derive from the innovation . This does not imply that innovations shou ld never be introduced but it does imply that they should be more objectively ev aluated than hitherto, and that the notion that w hat is new must be better should be constantly questioned.

Man introduces many limitations into the syste m which become more apparent with increasing automation. In adapting the system to man's limitations his strengths as a system component should not be forgotten . In particular his greater flexibility means that the matching between the man and the machine, if the system has not been properly designed, has to be done by the man extemporising. Changes of informatio n from qualitative to quantitative, incomplete automation, and the apparent retention of decision making roles which in fact have been greatly changed , all lead to problems in e nsuring that the information displayed can be used . In addition, changes in activity, in procedures and in automated assistance may alter the roles which must be fulfilled by the man 's memory and by his attention. To an increasing extent the display must assist him in such higher mental functions.

In a paper of th is kind , surveying cu rrent and forthcoming problems, inevitably a note of pessimism tends to be struck. This however is not fully warranted . Some past mistakes are no longer being made (10) . It is hoped that by drawing attention to these problems in the provision and use of information many of them can be forestalled and the remainder can be successfully ove rco me.

References

a. v. o.

Ho pkin . A survey of communications in Air Traffi c Control.

RAF Inst itute of Aviation Medici ne SC. Memo. No. 92, 1969, Farnborough . Hanis.

9. R. E. Christ & W . H . Teichner. Co lour research for visual d isplays. 1973. New Mexico State Univers ity : JANAIR Report No. 730703.

10. H . M . Parsons . Man-machine system experi ments. Baltimore : John Hopkins Press, 1972. /\ c.knowlo dgornonl ; "fh1a p np~ r w n o f1 ro\ p u b l l::sll e d

by t he Advisory

Group for Aerospace Research and Developmant (AGARD). NAT O ' " the Proceed ings o f fh Q ?Pih Me .. uno o f the Guidance ancl Control l"!ln f' I o n " P leng aild Dellel o pmenl a for Ai r T r Rll lo !;ly tolom o "' , C arn bndg6, Massaehusett5 - May 1971!.

The installation atop the Pan American Building, which co rporate, military and government officials have visited , served as a "protected airc raft." The Litchfo rd collision avoidance plan has been stud ied by various Federal officials. Mr. Litchford has more than 40 patents, mostly relating to aviation. He received the 1974 pioneer award of the Institute of Electrical and Electroni cs Engineers.

(New York Times)

Once again I have been confronted with the problems o ur fellow controllers in developing count ries are faced with. Our Federatio n has a great responsibility towards them, and the time is near for us to consider more carefully what we can do to help the Associations in those countries in achieving recognition for the air traffic controller's professio n. We shall soo n have to define a general policy with a view to providing better assistance to Member Associations in developing countries.

(J-0 . Monin , President of IFATCA. after his visit to the Moroccan A ssociation, 13/19 Novembe r, 1975)

Jon Sharpe's article on his experiences as a controller with RDP, which appeared in the November 1975 issue of " The Controller", is one with which every controller will agree and many have probably had it in mind to write over the last ten years. He has done a good and timely job. In my opinion he will demonstrate to the perpetrators of the present radar system that you cannot keep piling stuff on to the PVD before ultimately the controller loses the picture because he has got too many "pictu res" to look at. The present trend to me, as a radar controller from wartime onwards, has neve:r been a viable proposition. especially when one has to become a co mputer operator as well. It isn't that I am against rad ar but it is about time that the planners r1=Jgog n1secl its limitfltio ns. T hero is 8 body or opin ion In the U SA w hich prppl1f::>l o:> fin ond o f rad a r I n Its present format and vs 111 m oao urob l a time I wo uldn't for the 11~x1 20 years at least do away w ith rada r Which can be usod compatibly on til e Planner/ ExeautiVO b<1$ls quite Woll but it Is past limo that th e pro po nont s of tho system stopped loading It to the detriment o f th o co ntrollor.

(T. H. Harri son, Executive Sec retary , IFATCA)

Brief Items George B. Litchford, originator of many inventions for aviati o n , has been granted two patents on his aircraft collision avoidance system, which he has d emonstrated atop t he Pan Am erica n Building in New York. Mr. Litchford has proposed a national procedure in w hich the aircraft will use the signals from the ex ist ing Air Traffic Control system and automatic responses made by ai rborne instruments call ed transpo nders. Hund reds of ground radar stations now communicate with 100,000 aircraft.

The patents provide means of measuring distances and direction s between airc raft an d the determination of the prot ected plane's own positio n. This information, passed t hrough a sm a ll co mputer w ith ot her data, provides the pilot w ith a pictu re o n a cathode ray tube of any nearby airc raft or an o bstruction , such as a mountain peak, marked with a sta ndard beacon. If there is a potential collision, the p ilot is automatic ally warned and c an change his course.

14

Pilots of small aircraft landing at contro lled ai rports behind large or heavy aircraft will find a n extra mile of separation between them and the plane ahead under new FAA procedures. The precautionary action is being taken as a result of recent wake turbulence stud ies. Under the new procedures, FAA requires a small aircraft to have a six-mile separation when landing behind a heavy aircraft and a four-mile separation when behind a large aircraft, judged w hen the preceding aircraft is ove r the fen ce.

A "heavy" aircraft is described as one of 300,000 pounds or more and includes the DC-10, L-1011 , B-747, the CSA military ca rgo plane and larger B-707 and DC-8 models. A " large" aircraft is one 12,500 to 300,000 pounds, and includes the 727, 737, the small er 707 and DC-8 and some business aircraft. "Small " aircraft are those 12,500 pounds or less, covering most of general aviation, in cluding air taxis.

(FAA Avi atio n News)

The 1976 IFATCA Conference, Lyon, France

15 th Anniversary Marke d by Efficient O rganisation,

Splendid Hospitality and Huge Working Programme

Sueeessfully Completed i he thought of celebrating li=ATCA's 15th A nnive rsa ry was one th ing, but the members of the Executive Board were far more conce rned with the questi on w heth er the tran sport arrang ements between the hotels and the Congress Hall would work out alright, wheth er the wo rk of the three Conference Committees could be compl eted within the time allocated, wh ether deleg ate "X " from country " Y " was satisfied with the way the techni cal and professional aspects of the controller's profession were being dealt with , and if the news medi a would do a fair job thi s time w hen reporting the Conferen ce. When all these matters turned out as hoped for, it was time after the closure of the Conferen ce to turn to the 15th anniversary celebratio n, and for the hundreds of controllers, authorities, observers, and even the Board to let their hair down in the incompara ble IFATCA spirit wh ich can never be really understood unless you attend a Conference yourself.

Lyon's Palais des Congres, for five days, becam e the headquarters of the worl d's controller wo rk-force and they made Lyon their capital city of Air Traffic Control. After 14

Confe rences held in Europe, Canad a, Iceland , the M iddl e East and Australi a. IFATCA's An nu al Conventio n retu rn e d to the Co ntinent of Europe, and It was very f itting th at t he 15th anniversary of the Federation was held in France where the First Annual Co nference took place in 1961.

When they p roposed Lyon as t he host c ity, the Fre nch "Associati on Profess ionnelle de la Circulation Aer ienne " (APCA) undoubtedly wished to pay t ribute to a ci ty whose dynamism and energy have placed it in a leading pos ition in Fre nch Civil Aviat ion. A nd the citizens of Lyon soon became aw are th at their Cong ress Hall this ti me was reserved for a very speciali sed g rou p of people indeed. In t he words of Lyo n's Deputy Mayor M. F. Blanc : " Before t h is C onference, we didn't know anything about Air Traffi c Control. and your profession should be advertised more." From these words we can again take to heart t he c lear lesson th at in s pite of all our effo rts we still have a lo ng ha ul ahead before we can affo rd to ease up in ou r p ro mot io n wo rk, and may th is t ruth particular ly strike ho me to that spec ifi c group w hich this year wit hdrew its support from us.

15

The variety of colours and the beautiful botanical garden scenery of the park across the street meant both relaxation and inspiration to many a d elegate.

The Opening Ceremony The Conference was opened by Monsieur Marcel Cavaille, Secretaire d 'Etat aux Transports. The Minister said: • J'al l e grand plalsir de vous souhaiter la bienvenue ii la quinzieme Conference d e la Federation internationaie des associations d e contrOleurs du trafic aerien qui, a lieu en France pour l a deuxieme fo is : en 1961, en effet, a la c reation de l ' IFATCA dont !'A ssociation Professionnelle de la Circ ulation aerienne franc;alse etalt membre-fondateur, l a Conference s'etait deroulee ii Paris, avec une poignee d e per sonnes, dans des conditions beaucoup plus modestes: l a vue de l a nombreuse assistance que ]'al au jou rd'hui d vant moi est l a preuve evidente de l'etonnante vitalite de cette F:deration . J'apprecie le choix de Lyon, deuxieme metropole de France, pou r assise de c~tte _confere~ ce : i:histoire ~ ro u_ve que cette ville, creee par les romams rl y a vrngt sre.cl es,. n allart pas seulet etre le confluent de deux grandes vores d eau, mais le con~en t culture ! et commercial de d eux grands courants de civills~~~n. celui de ! 'Europe septentrionale et celui , par le relais de la republique de Venise, de !'Orient. . . les representants des quarante-deux assocrahons-membre d ' IF~~CA se rencontrent ii Lyon aujourd 'hu_i obei~ done davantag~ ii une tradition qu 'a une coincidence: tradit'.on. qu1 se t.radult auss1 en 1976. dans le domaine aeronautique, par I existence d un ~~roport international dont nombre d'entre vous auront sOrement utilise les services ii leur arrivee. L' aeroport de Lyon-Satolas a ate inaugure

a

ii y a un an.

I Passant du plus particulier - Lyon - au plus ~enera l -:- ~ France, carrefour de routes aeriennes -. le but ~ u e ie . po ursurvr~r m aintenant sera de presenter l e contrOl e du traf1c aerren . f'.an ~a rs r' gnes certes mais surtout dans l es orrgrnalrtes dans ses gran d e S l • • , . ui euvent l e distinguer du contrOle d ans d autr.es pays, p~1sq u e. de fondement com mun des services de c 1rcu lat1on q p .I toute fac;on . e d I f aerienne est dec rit, en termes connus de tous. 1e~ gens e a ~r~ esc 0 nvention d e Ch icago. La prmc1pal e caractenst1que . sron, dans 1a d 1 • • . ,_ · f anc;ais est d 'etre c ompose d une part e survo s du traf1c a.,nen r d f i • e · e im ortante : deux avions sur cinq ans 1 espace a rren ranc;~ s tr s P . qui ne font pas escal e sur un aeroport franc;ars. sont des avrons . . . rte 1 provient de la position geog raph1que de l a France Cette ongrna . f 1 .t d 'elle le carrefour de plusi eurs courants de 1 e~ Eur?pe . ~u. nane importants: celui qui relie les Ameriques ii c irculati on a.,rre . · · 1 l'E d nombre d e pays du »Vieux c~nhnent• , celu1 qu1 rel e urope u N d ii t 0 us les pays du soleil. or . de 1 soo ooo mouvements ont ete ainsi contrOles L' an dern rer, P1us . . entres »en route« franc;a1s. Cec1 represente une dans les qua~~~o c mouvements contr61es envi ron par centre et par moyenne de d e . onnable s ' ll en est, puisque le propre du trafic jour: c~lcul ;ars ei ui que je viens de decrire en particulier est de en ge~eral et e .ct·ons tres importantes et tres irreg ulieres dans le conna1tre des varra 1 . . · des pointes, saisonn1eres, journalreres et horarres.

1 temps, notammd.etn s ii est comprehensible que depuis une qu inzaine Dans ces con ' ion • ,. i • admin istration ait fail developper un syst.,me nd an nees. md?n . tance automatisee au contrOle qui offre des faciliformatique ass1s . ,_ t t' on des informations sur les av1ons aux contrOleur s tes de pr ..sen a 1 .

• h insl de consacrer moins de temps aux lac es . et leur perme t a 11 es . . lus d 'attention aux conflguratrons toufours nouve repehtrves e 1 P . . et inattendues du trafic dans le c 1ei franc;ars.

16

Amel iorer en permanence le system e, sa capacite, sa f iab ilite, amel iorer l es conditions de t ravail et la qualite de vie d es hommes ou des femmes qui contribuent a un titre ou a un autre. a l'efficience des services de contrOle fran c;ais, telle est l a ligne d'action que nous suivons, dans le cadre d ' une concertation m enee ii toutes les etapes de la chaine qul assocle les contrOleurs , les chercheurs et les gestionnaires de !'Administration, les utilisateurs des compagn ies aeri ennes, les fabricants de l'lndustrie enfin.

Les espoirs du systeme de 1976 constitueront l es principes du contrOle de l 'aeronautique de demain. C'est ainsi que d ans les eludes pour un successeur au systeme d 'atterissage aux instruments actuel, la France a resolument cholsl de porter son effort au dela des specifications admlses, vers un systeme entierement automatique d'echange de donnees entre calcul ateurs disposes au sol et a bord des avions, systeme global qul slmpllfleralt radlcalement le deploiement de nouvelles aides et allegeralt aussl, dans la v oie dejil ouverte par l'atterrissage tous temps, les multiples responsabilites des pi lotes et des contrOleurs dans cette phase cruciale des vols.

Dans les centres de contrOle en route, l'essor du nombre l es vol s pose des options pour le futur. Parmi celles-cl, nous avons resolu de multiplier les centres, dont le nombre passera de quatre a six ii !'horizon 1985, plutOt que de perseverer dans l e gigantisme des centres actuels, nuisible a l'epannouissement des personnels qui y travai llent.

Ces nouveaux centres jouiront en outre des tout dern iers progres en matiere de technologle et de methodes appliquees a l a circulation aerienne. II n'est pas exagere d 'attendre que la detection et la resolution de conflits contrlbuent ii !'amelioration de la securite mais tendent aussl ii alleger !'effort constant de vigilance des contrOleurs; ni d 'esperer que des d onnees t ransmises par satell ites. en matiere de trafic suboceanlque par example, permettent d'apprehender avec un meilleur preavis les configurations de trafic entrant et concourrent ii favori ser les actions de regulation de trafic. benefiques ii l 'economie du transport aerlen.

Dans les prochains jours , VOS travaux contribueront a !'evolution du contr61e du trafic aerien, sans lequel II ne serait pas d e transport aerien heureux. Depuls sa fond ation en 1961 , l ' IFATCA, par l'etendue progressive de son domal ne de competence, a contribue activement a !'amelioration de services de contrOle du traflc aerien ii l 'echelle lnternationale. Je me rejouls de reconnaitre qu 'elle a notamment su allier son efficacite ii un sens de !'adaptation tres pousse. que reclame, dans l e monde de !'aviation clvlle, !'evolution tres rapide des techniques et des perform ances des avions. II est rassurant de penser, par exemple, qu'elle avail lnscrit depuis plus ieurs annees au programme de ses travau x l'lntroduction de l'avion de transport superson ique dans l a circulation aerienne t raditi onelle, contribuant ainsi ii faciliter la mise en servi ce de !'aviation de d emain, devenue, au debut de cette annee, une realite dej il quotidienne pour plusi eurs pays.

J'espere que vous passerez une excellente semaine ii Lyon .•

Mr. J-D. Monin, President of IFATCA, was the next speaker. Here follows an extract from Mr. Monin's address.

"An enorm ous task lies ahead of us. The first few years will have to be devoted to the formation of a sound internal administration, with due regard to the very limited fin anc ial fund s. It would be very unrealistic to start tackling all probl ems at the same time. A good choice has to be made and priorities to be determined . The Constitutional Meeting has given the "c leared to start eng ines."

I sincerely hope that within a reasonable time the "cl eared for take· off" wi ll follow. Although an uninterrupted c limb i s expected, we all know that a lot can happen before the flight is on its way."

With these words, the first President of IFATCA, Mr. L. N. Tekstra, addressed the Constitutional Conference of the Federation in Amsterdam in 1961 and six months l ater, in his opening address to the First Annual Conference in Paris, " Tek" continued : "We sincerely hope that in the near future controllers from all over the world will realise that only a combined effort can give the profession a voice Internationally. Only by using all avai lable practical professional knowledge and manpower can we hope to build up a sufficiently strong organization, which is capable of taking up and hol d ing its place in the international world of aviation. We will welcome any proposal which may facilitate the affili ation to our Federation of interested Associations from anywhere In the world , provided that the object of its affiliation Is in the first place to offer co-operat ion to the benef it of the profession."

During the past year I have often been asked why IFATCA should cel ebrate its 15th anniversary, which i s certainly not usual for a jub ilee. There are however seve ral reasons fo r such a decis ion. After having peregrinated around the world, IFATCA i s fo r the first time coming back to a country that has already hosted an Annual Con-

The head table of Committee "A" saw one of the IFATCA veterans in the chair.

From the left : Vice-Chairman R. Pile, Rhodesia; Chairman M. Cerf, France; Secretary A. Maziers, Belgium; IFATCA Vice-President Adm inistration E. Bradshaw, and past Treasurer J . Gubelmann.

ference in the past. But above all when it comes to celebrating anniversari es, it Is usually the occasion not only to look back into the past but also to plan f or the future. Bearing this in mind I think that T ek's words pronounced 15 years ago are st il l of great value.

Indeed the take-off clearance has been followed by a regular climb but the Federation today has still not reached its cruising level and much remains to be done.

It is indeed sad that our friends from the United States are not with us in Lyon and this shou ld prove that there are still control lers who have not yet realised that only a combined effort can magnify the controllers' voice internationally and who in withdrawing only considered the question "What has IFATCA done for us?" but never thought in terms of "What can we do for IFATCA?" What has IFATCA done for controllers? The answ er to that question needs consideration of the reports of the past 15 years and this wou ld be taking too much of our time today. But I think the main thing is that the controller now has a personality internationally and that his voice is heard and furthermore that those controllers who cannot make themselves heard at a national l evel or who are sufferin g from discriminations know that the fri endship and solidarity of their fellow controll ers the world over are not conceited words. With this in mi nd I remain confident that the ·present attitude of PATCO may be changed. Therefore it is important that all the Associati ons represented here today give c lear answers to the question "What can we do for IFATCA?" The Federation today i s representing the controll ers at international gatherings . At t his time we have delegates attending the 9th Air Navigation Conference of ICAO; others have just returned from the ICAO Fourth Informal Meeting on ATS problems in Central and Eastern Europe and from the XXX lst IFALPA Conference , and plans are in hand to have IFATCA representati ves attend the ICAO In.formal Meeting to discuss provision of ATS in the upper airspace within the Auckland Ocean ic FIR and above the Nandi FIR. The importance for the control lers to have t he Federation participate in the ILO Civil Aviation Conference to be held in l ate '77 cannot be ~::remp~asised and there are in add ition many other meetings like Medical Symposium held in Manchester 10/ 11 April 1976 the recent Internal'1ona 1 c ongress for Av1at1on . . and Space Medicine,• etc .

I cannot quote them all. d

lh would like to recall t he memory of Tommy Thomas whose Just before Christmas came as a shock to all those who knew bimT For ~any years the IFATCA Conferences have been marked y Eommy. s presence either in the chair of Committees or with in th e xecut1ve Board a d h · . . .. difficult situatio _n is si~cerity and ab1l1ty to resolve the mo~t . ns with his incomparable sense of humour will remain as an example to all of us."

h~at

The Work of the Conference By the time this issue appears Member Associations wi ll have received the comprehens,ive Conference Report which in detail lists eve rything which occurred, but for those

readers w ho may. not be in the pict ure, the following brief resume should be of help: Five new Member Associations were admitted, namely Costa Rica, Egypt , Morocco, Portugal and Sudan, bringing total membership to 46, and no less than a further 11 new Corporation Members received their Charte rs, making thei r total 36. They were : The Mitre Corporation, Gustav A. Ring , Sofreavia, Societe d'Etudes et d' Entreprises Electriques, Societe d 'Appli catio ns Generales d ' Electricite et de Mecanique, Societe Artistique Fran9aise, Ulmer Aero nautique, Compagnie lnternationale pour l'lnformatique, Telerad , Elecma, Airport Lighting Engineering Consultants. Mr. H. H. Henschler (Canada) and Mr. H. Wenger (Switzerland} were unanimously elected as Vice-P resident (Professional) and Treasurer respectively, and the meeting with reg ret took leave of Mr. J . Gubelmann who had served IFATCA so well for 6 years as Treasurer. A new, increased scale of subscriptions was accepted; the 1977 Conference wi ll be held in Cyprus from 25-30th Apri l 1977; Copenhagen (Denmark} w ill be the scene of IFATCA '78 from 1st to 5th May 1978; and Turkey's invitation to host the 1979 Conference was provisionally accepted.

With regards to the continued lack of progress for an alteration of IATA Res. 200, the Federation decided that its efforts in thi s directio n should be contin ued within the terms of the 1975 Resolution, and that in the event IATA at its 1976 Traffic Conference fails to agree to the request of IFATCA, the Federation will support any Member Associ~­ tion in its endeavours to implement those Ree. with their IATA carriers. The IFATCA Scroll of Honour was awarded to the Swiss Association for their outstanding service in IFATCA's Standing Committee 111 (Finance).

Th e Technical Conference Committee dealt extensively with Working Papers regarding IFATCA 's input to ICAO's 9th ANG and to ICAO's Informal West European Flow Control Meetings and Informal East European ATC Problems Meetings; Airborne Collisio n Avoidance Systems, Linear Holding, Effect of Automation on the Controller and the ATC System, Tu rbulent Wake, Civil/Military Integration, Simultaneous Use of Parallel Runways, Speed Control/ Rationalisation on ATS Routes, SST First Operational Report, Bl ock ing of ATC Frequencies, Inc ident Investigation Procedures, and - at the request of Canada - dealt w ith the subject of " Universal Language of ATC Comm unications" .

17

Perhaps for the l ast time John Saker, U.K., appeared in the chair of Committee " B "; Vice-Chairman R. Stephenson (S. Africa) and Secretary D. Nankivell (Austral ia) completed the team. Difficult to imagine fu ture Conferences without John's expert chairmansh ip.

On this topic , the following resolution was eventually passed in Final Plenary: "That Conference defer voting until IFATCA '77, pending sufficient input on the subject f rom all Member Associations and ample study by Standing Committee I." The Professional Conference Committee dealt with a number of Reports submitted by IFATCA delegates to international meetings; Working Papers on such subjects as Job Analysis , Medication in ATC, Design and Layout of ATC Equipment and Operation Rooms, Synthesis of Medical Researches in France, Recruitment and Training, Interrelation of Rec ruitment and Training with Automation; Advanced Training, Assessing and Rating; Legal Matters; Controllers' Legal Liability an d Means by which an International Convent ion may be introduced through ICAO; the Controller in Aircraft Accident Investigation, etc. The Committee was of the opinion that the presenGe of Prof. Hopkin and Dr. Wagstaff during the discussions was of much assistance.

Conference Highlights Undoubtedly, the special Medical Panel Session on the aft ernoon of the Opening Day and the Technical Panel Session on "Strategic Air Traffic Control" on the last but o ne d ay, were highlights of the Lyon Conference. The Honorary Chairman of the Medical Panel, M. Michel Mangenot, Directeur du Pe rsonnel et de !'Administration Generale, Presid ent of the Committee o n Medical Studies regarding Controllers carried out in France, said that he was much impressed by the f act that side by side with the technical aspects of the controlle rs' profession, the Conference work prog ramme co nta ined a part dedicated to its psychological and physio logical as pects. Mr. Mangenot continued: " I have been c onvinced for a lon g time that it is essential in the functioning of every profession, and so much more so w hen the profession touches directly the safety of others, to use every possible method to ensu~e the physical and human eq uilibrium of those who carry 1t out, and I d eeply apprec iate that IFATCA has emphasis~d that in the deliberations of t hi s Conference. I am convinced that the doctors, psychologists and the French contr~llers who have carri ed out _ together - serious and fruitful medical resea rch over the past few years, made an important contributi on to these studies." The Panel's aim was to help delegates of t he Member Associations t o become more fami18

liar with medical aspects so that everyone can make more input to Standing Committee IV in the future. Doctors of the Panel were familiar not only regarding medical problems of controllers but also with the controllers as individuals, and this permitted a very interesting exchange of ideas between them and the delegates.

The Technical Panel Session was chaired by former IFATCA President Arnold Field, present Chairman of Stand¡¡ ing Committee I. The Session was divided into two parts : "equipment" and "operations". Two experts from the French Direction de la Navigation Aerienne, Messrs. A. Monnier and L. Deneufchatel, Mr. W. H. Endlich, former Editor of "The Controller'.' and Mr. T. K. Vickers, Editor of the "Journal of Air Traffic Control", as well as a number of representatives of IFATCA's Corporation Members, took part in the proceedings. In explaining to the audience why the Federation had chosen the theme of "Strategic Air Traffic Control", the French spokesman of the Panel outlined that after the relative stagnation of the 1974-1975 period, the recovery is clearly happening in 1976 and that we can presumably expect a rate of growth of 5 to 6 per cent for the medium term . But we shall not be able to cope with the demand of the next 15 years to come if we don 't prepare ourselves properly in order to solve in advance - off line - the main proportion of potential conflicts it contains.

Only a tremendous development of the concept of "Strategic Air Traffic Control" will enable our systems to overcome the iron law of the decreasing yields as the traffic grows.

Before outlining the fields of research the d evelopment of "Strategic Air Traffi c Control" is opening, the introductory speaker made two remarks concerning the evolution of the general environment in which we shall have to co pe with the problems and which will have a growing influence on the solutions available: the Airspace is becoming scarce in many countries, partic ularly in Europe. Solutions in Strategic Air Traffic Control will thus have to be airspace saving and will have to integrate the time factor; sensitivity of Public Opinion about the noise issue is becoming a fund amental parameter to take into consideration and in a volume which is much larger than the near surroundings of airports. In the same way, the difficulties encountered in the creation of new airports will promote a more and more inten sive use of th e existing ones.

A new team at the head tabl e of Committee "C" gained re spect and r ecognition among delegates. From the l eft : Vice-Chairman J. Ka lvik, Norway ; Chairman E. Just, Germ any; Secretary N. Loaney, Australia.

-·.. : ..·...-

..... .a-• ,._

. -. -·

-· ,..

~-

>CJ

..... ...

~-

·~"'·~-

l .. --- ......... ,

The representatives of the new Member Associations received a hearty welcome to the Federation. Shown are the delegates of Egypte, Marocco, Portugal and Sudan.

The new problems of the future and the essential dimensions that have to be introduced in the strategic organisation are issues that are going to be discussed at this Panel and are also in the work programme of this Conference.

It is planned to pub lish reports of both the Medical- and Techni cal Panel Sessions in the next issue of "The Controller".

IFATCA '76 Technical Exhibition One of the basic major features of the Federation is to gather together active controllers and firms who develop and build the tools of the future required by the constant increase in air traffic. In between Annual Conferences IFATCA maintains constant contact with its Corporation Members through the J ournal, Circular and daily correspondence regarding the need, anywhere in the world, for new electronic equipment, communications, new Centres, Towers, airports, lighting, etc. etc. Corporation Members of IFATCA do not support the Federation simply by financing. They participate as observers in all the sessions during Annual Conferences wherein they may freely debate any technical or professional matters. In Lyon, the best part of a d.ay was set aside for the Corporate Members to present their points of view; this apart from the Technical Panel which in itself affords singular opportunities for the inter~hange of ideas on many topics. The Technical Exhibition IS a "C arrefour" where controlle rs, experts from intern ational and national organisations, air carriers and aviation et onhc~rns can meet to discuss problems, procedures and ec niques.

This _Year, an exhibition space of 1000 square metres

elations' publications was also in operation. The so-called "Salle Rouge" of the Congress Hall with a capacity of 40 seats and fitted for projections, etc. was at the exclusive disposal of Corporation Members for the purpose of showing any presentation they cared to make. On the second floor, French Corporation Members and a large number of other French firms had rented space for exhibition. This gave an additional interest to the Conference and helped in covering expenses. SOFREAVIA, a new Corporation Member of IFATCA, had been kind enough to co-ordinate all presentations on this floor which was so fully booked that there was a waiting list for possible vacancies on the first floor. The whole 1976 Exhibition was most impressive, easily the largest seen at an IFATCA Conference, and drew much attention, not only from Conference participants but also from interested Lyon citizens.

Three meetings attended by Corporation Members and by officials representing the Federation were held to discuss certain items related to the participation of the Corporation Members in the Conference, the communication between them and the Federation, and to prepare for the Technical Panel Session. The desirability to appoint someone who would assist in the co-ordination between Corporation Members and the Federation was reiterated. After discussions as to the need for a form~I election, probably involving time-consuming procedures in ·ir of Stancontacting absent members, Mr. Graham W 1 1ams . t k and unanimously saab was proposed to take on t h 1s as . . accepted. From the Federation's side, the Ed1t?r will continue to have special responsibility for safeguarding the interests of Corporation Members within the framework of

:a.~t available in a Congress Hall specially designed and

IFATCA.

thui for. the purpose of holding large Conventions · in fact e Palais des Congres is the location of the famo~s "Foir~ d e Lyon" A M b · complete presentation by the Corporation em ers was organised on the ground floor in the large entrance hall of the Palace. T wo panels w;re offered to each of _them to display their best posters, pictures, etc.

Corporation Membe t · . rs ou s ide France were allocated a preferential location f . or more extensive exhibition purposes ~n the first floor. There, Cyprus, the organisers of IFATCA 77, were offered a special stand, while a promotion stand for the presentation of the Federation 's and Member Asso-

1sth Anniversary Celebration After the closure of the Conference by APCA President Daniel Gorin, a ninety minutes' long special ceremony was held commemorating the 15th anniversary of IFATCA. Former Officers of the Federation related some of their experiences in the early years of IFATCA, and presented their viewpoints on current Federation developments. In this manner, the audience was given an illuminating insight into the breathtaking development of the Federation since its inception, and the accounts by the former IFATCA stalwarts,

19

often interspersed with amusing comments, in particular the story presented by former President Maurice Cerf was related in humourous vein, were well appreciated and much applauded. It is planned to reproduce the various viewpoints which were expressed in the next issue of this journal.

Award for the Best Article Published in "The Controller" in 1975 During the Conference it was announced that the 1975 Award for the best individually submitted article for the IFATCA journal had been awarded to Mr. Jon R. Sharpe of the Chicago Air Route Traffic Control Centre. His article "An Evaluation of Radar Data Processing" in the November 1975 issue of "The Controller" was the first article of its kind published by the Federation and written by an operational air traffic controller. The Award was in the form of a book especially selected for the purpose.

Acknowledgement The Executive Board wish to place on record their deep appreciation on the part of every one who attended the memorable Lyon Conference to President Daniel Gorin of APCA, his Board, the organising committee under Jacques Lienard and other willing helpers of the home Association, all of whom deserve full praise for their tireless efforts to guide the Conference to a successfull conclusion and for catering for the many needs of representatives from over 50 countries. None of us will easily forget the striking bond of unity through the job which existed among the controllers present. Coloured or white, gaily robed or in suits or jeans, it made no difference, and on the final night's farewell function, our guests from the medical profession, other aviation organisations and those others who had been invited were treated to the singing and exuberance of an endless table comprised of people from all corners of the globe who every so often would rise to a toast with such strength that they drowned the output of a six piece electronic band.

Comments On Air Traffic Control From Far And Wide J. M. Livingston, President, Canadian Air Traffic Control Association, on the subject of trainees: How many times in your career as a controller have you had a trainee? Most of us have undergone the experience at least once; I can assure those of you that haven't that as long as you remain active in the control of traffic you will eventually undergo the experience, which not only includes training the aspirant but writing reports on his progress and recommending "check out" or, in the event he is unsuccessful, ceasing training. we have become aware over recent years of a disquieting number of cases where an instructor responsible for providing on-the-job training has apparently certified that a trainee should be checked out before he was ready, or even in some cases, where he would never be capable.

The reasons given are many and varied, for example: "He was going straight on to IFR training and would never work in a Tower anyway."

20

"The Chief insisted that I check him out because he was needed right away at another unit."

"I didn't want to be responsible for ruining his future career in ATC." We claim that we are a professional group and one of the features of most such groups is a system of selfregulation. Air Traffic Control is the only field wholly within the Public Service which is in such a position and it is incumbent on all of us to remember our responsibilities in this area.

The results of such an unprofessional approach as I have described appear when licensed controllers appeal to us for support in fighting dismissal on the grounds of incompetency early in their careers. Several such cases have been investigated and reveal the kinds of situation mentioned earlier, except that the guy who was checked out to go on an IFR course, didn't pass it. All of a sudden he is back in the Tower where he was originally checked out with a valid licence to work there.

If someone doesn't have the integrity to reveal the evident incompetency now, the individual carries on and over the years several things happen. He is a burden on his co-workers who must assist him in his position, as well as carry out those of their own, with the consequent degradation of safety. He becomes increasingly bitter and unhappy as he realizes the situation, with the obvious effect on his own well being and on relations with his coworkers. In the course of time, he will also be assigned trainees who will be checked out if they achieve his own level of ability, thereby allowing additional sub-standard applicants to be licensed. Last but by no means least, he could cause an accident, an accident which really is your responsibility - remember, you checked him out originally.

Think about it. You aren't doing anybody a favour by being "Mr. Nice Guy" and qualifying the unqualified - not him, not yourself, not your fellow controllers, management or the system and, most important, not the flying public for whose lives we are responsible.

Domenic V. Torchia, Deputy Director PATCO at IFATCA '75, Melbourne, in a letter to the Australian Host Association: "Your Association is a well run unit that is faced with the same professional goals as the controllers in the U. S. I could not help but notice that many of the members possess the same unrest that we here in the States had in ~ 970. If this observation is correct then I wish you success m your challenge for parity in the aviation industry. However, study our mistakes and learn from them as they will be a great asset to you. Primarily, remember that our greatest advances were made under the leadership of controllers. Our greatest downfall came from the guidance of misinformed legal personnel. Remember that controllers themselves have the talent and know-how to make the necessary gains."

Colonel Edward V. Coggins, Jr., Asst. DCS, Air Traffic Services, AFCS, on professionalism: We are involved in a very serious and demanding profession, in which there is just no room for error. I think that the great majority of our professionals know this.

I am concerned about those few who fail to realise the great burden that is placed on their shoulders. Somehow, some way, we must reach these few and instil! in them the pride, professionalism, and great responsibility that is inherent in the job of the air traffic controller.

Air Traffic Control in Sweden (Part II) The Malmo ATC Training School Many years ago the Swedish aviation authorities recognised the need for "a continuous increase in efficiency and capacity within the Air Traffic Services Organisation" and they set out to do something about it. After careful examination of contemporary training methods, which separated military and civil ATC tuition, they recommended that "joint training of civil and military controllers must be located in a special training centre and that this centre must be equipped with a modern ATC simulator and modern teaching aids." That was in 1967. The result of this report was the ordering in 1972 of equipment for the new centralised ATC Training School to be located at Malmo's Sturup regional airport, replacing the civil school at Bromma and the military school at Hagernas. The new school, which occupies a space of 6,500 m2 (70,000 ft2), was opened in October 1974, and is now responsible for the training of all air traffic controllers in Sweden, both civil and military.

The full course lasts 28 months and is designed to pass out 80 qualified controllers each year. After the course the students are rated at every ATC position in both civil and military control establishment. The syllabus includes an eight-month course for ATC assistants and the college has room for a number of overseas students; maximum accommodation is for 200 students. The building housing the college was constructed for a total cost of £ 1.2 million, with a further £ 1.4 million being spent on the SATS simulator.

Stansaab Elektronik AB, IFATCA's Swedish Corporation Member, was awarded the contract for the main simulator for area radar training, known as SATS (Simulator System for Air Traffic Services); this facility enables various air traffic situations to be simulated simultaneously on 12 synthetic data display screens. The system is driven by a ~tansaab Censor 932 computer located beside the operations room.

SATS - Functional Description SATS is intended to simulate all present and future civil and miTt 1ary ATC systems, without interference to the operational Air Traffic Control system or hazarding aircraft safety. SATS is modular and may be reconfigured readily to create virtually any traffic situation in a realistic environ~en~· A~art from its teaching function, the college is also uctmg a continuing evaluation of Swedish ATC proced~~es, and present and future demands for both civil and military ATC sy t s ems may be reproduced thus enabling ~ew operational procedures to be investigated and tested in a practical situation. . c_omplete facilities are available for basic or specialist training. Previously qualified controllers may return for refresher courses or be given more advanced training in ~ew techniques. Stress and emergency situations may be introduced realistically without risk to flight safety, and controllers are thus better prepared for the responsible ta.sks encountered in operational Air Traffic Control work.

Dimensions of individual equipments e.g. synthetic dynamic

display (SOO), electronic data display (EDD), communications panels, are standardised, thus permitting easy rearrangement to investigate and resolve ergonomic problems. SATS provides for evaluation and optimisation of a single control position or a complete Area Control Centre.

The system's Censor computer provides the following outputs: 90 aircraft of 30 different categories, all of which are individually programmable and "flown" by the "blipdrivers"; three radar stations, each with primary and secondary radar returns; two direction-finding stations; 50 different standard approach routes (STARS) and 45 standard instrument departure routes (SIDS); 25 different holding patterns; 120 different interrupted approach procedures (ILS, etc.); 400 geographical positions (reporting points, obstructions); 4,000 stored simulated flightplans (SIMPLN) and 500 stored training plans (EXEPLN).

Flight strips are printed automatically.

There are 39 different positions in the simulator, namely: 1 Excercise Supervisor position; 12 Radar positions, each with a 16 in radar screen; 5 Procedural control positions; 5 Assistant's positions; 14 Pilot's positions; 1 Simulation Operator position; and 1 Radar position with horizontal SOD and 3 Operator's positions.

Realistic Simulation of the ATC Environment A complete series of operational positions is provided for planning- and radar controllers and their assistants.

Each student's position has an EDD, as well as the radar PPL Alphanumeric keyboards and rolling balls are used for data input to the central computer system. Di~ital EDDs (40) display details of aircraft under control, flight plan information, time, meteorological data and status of the various types of navigational aids. The student ~an write in the EDD lists, label information and use the rolli~g ball for continuous variation of the displayed range, with . on the SOD. the actual range .indicated a1phanume r"cally 1 Display selection facilities enable targets to be labelled fully with continuously up-dated identity,. ~ltitude .a.nd vel~~ city information. He can select either c1v1I or military c ordinate systems, various map comb.inations, vary the centre and presentation of his PPI, define the SSR ~odes to be displayed, select airfield approach tracks to~ display OD the Mode C altitude layer to be displayed, b · · ft on th e S . select various label formats, and he can o tam a1rcra prediction position between one and nin~ minutes ahead .

He can measure relative range and bearing between any two points, aircraft to airfield or aircraft to aircraft, for example with the data being displayed on the SOD. Conflict prediction vectors derived from the aircraft's course and velocity may be displayed as well.

The simulated radar derived air traffic situation is displayed clearly on digital SDDs (15) showing processed 21

The advanced system simulator installed In Sweden's Air Traffic Services Academy at Sturup, Malmo. From his position the instructor may select the radar picture and associated data from any training position.

aircraft radar returns with or without labels, with full moving target indication (MTI) and c lutter suppression, and elimination of the t raditional radar sweep. The required airway or area may be selected individually at each position. Map information, including airways, reporting points, terminal areas, airfields, land outlines, etc. is stored in the central computer and, therefore, readily modified for any particular training exercise or evaluation of new procedures. Aircraft symbology alters to indicate whether the return is d erived from primary or secondary survei llance radar and, if required, the SSR label of aircraft identity, altitude and speed can be deleted. Extended runway centrelines w ith range marks can also be displayed.

All simulated aircraft movements are derived from flight plans stored in advance in the central computer. The system ensures that each aircraft flies in accordance with the stored plan, unless the pilot overrides the plan and manually inserts an amendment. All aircraft are flown in accordance with pre-set c riteria for particular aircraft type.

Aircraft handover between adjacent secto rs may be achieved manually, semi-automatically or wholly automatically, according to pre-programmed variable c riteria. lnterconsole symbol marking is also provided for aircraft designation between the vari ous control positions.

The student has two R/ T frequencies on his console co mplete with interference, fading, etc., th rough which he communicates with the "pilots" of his "aircraft." The pilot, who may handle up to 10 aircraft, is eq uipped with an EDD displaying flight-plan information on the aircraft under his control and by radio passes the R/T messages which he has to make to t he controller. There is thus no written script and the programme proceeds as long as the pi lot deals with each message as it appears on the EDD. The c ont roller gives clearances or instructions as demanded by the developing situation, requesting the pi lot to climb or descend, change speed, hold, etc., in accordance with normal operational procedu res. The pi lot has an alphanumeric keyboard t hroug h which he co mmunicates such changes to his aircraft. The pilot may contro l ai rcraft altitude and speed , rate of climb or descent, rate of turn and angle of bank. He can initiate pre-programmed flight

22

routes, departure and approach procedu res, entry or departure from holding, formation dispersal for military training. change of R/T frequency and change in transponder reply code. And he can request airc raft position, aircraft speed, i. e. Mach number or knots ; aircraft fuel st atus, estimated time over next reporting point, and estimated time for attaining pre-determined flight levels.

The pilot also has intercom and telephone co mmunications. Additionally, some pilots have access to radar information presented on an .SOD. Flight status of the aircraft under co ntrol is presented in tabular form, consisting of identity, altitude, velocity, course, route, reporting points, ai rports of departure and destination, etc. Aircraft progress is indicated by means of messages on the EDD, written when the aircraft passes the appropriate en-route reporting points, or when clearing other pre-determined criteria, such as specific flight levels.

Exercise Supervisor Each student under training is watched by a tutor and the who le exercise is supervised by an exercise supervisor.

The exercise supervisor has overall executive responsibility for controller training. His conso le is comprehensively equipped with SOD, rolling ball, two EDDs, two keyboards and facilities for monitoring all radio telephone, intercom and telephone communications. Additionally, direct contact with individual instructors may be made by means of a separate intercom.

The instructor may select the radar picture and associated data as displayed at any training position. Usi ng the other EDD and keyboard he can "borrow" an aircraft from a pilot and insert alterations in order to c reate an unexpected conflict situation for the trainee controller. Each exercise is prog rammed to a given level of attainment and can involve any number of radar positions. As si mulation exercises progress, all voice communication is recorded synchronously by the computer controlled on-line voice recording system, together with radar and f light data.

The exercise supervisor can "freeze" an exercise at any time, thus stopping all aircraft and si mulated time of

Student controller at the system simu lator at Sturup, Malmo.

an exercise. The exercise may be restarted , allowing ai rcraft and time to proceed as previously. He may also decide to stop an exercise and go back in time for any period up to ten minutes and investigate that part of the exercise.

If required , corrections may be introduced by the instructor or trainee controller when restarting the exercise.

To improve analysis in evaluation exercises, the speed of the simulation can be varied from two-thirds to five times normal. Several d ifferent exercises may be run simultaneously, each of w hich may be frozen and restarted independently. Up to 13 simultaneous exercises can be executed .

Simulation Operator The simulation operator is responsib le for exercise preparation and technica l supervision.

Technical performance of the simulator system is monitored from the simulation operator's position (SIMOP), which is co-located with the computer input/output periphera l eq uipment. It comprises a radar contro ller position with SOD, rolling ball, EDD and keyboard , together with a pilot position equipped with EDD and keyboard. The computer contro l desk is also used for detailed system analysis. A number of one-line test programs are included wh ich automatically initiate print-out reports o n a typewriter in the event of fault detection.

The sim ulation operator is also responsible for preparing training exercises and defi ning any system configuration which is to be simulated. The following data is stored in the system and may be compi led into complete exercises: (a) Parameters - specifyin g performance of the various types of aircraft and characterist ics of the radar stations; (b) Simpln - the SATS equivalent of an operational flight plan (PLN) consisting of callsign, route, cleared flig ht level etc.; extra information required for the s imulator is also included; (c) Exepln - specifyi ng an exercise and determining system configuration, frequencies, allocation, sectorisation, hand-over points, w hich Simpln's shal l be used and time of activation; and (d) Metpln - meteorological

data desc ribing weat her conditions at the exercise airfields.

The sim ulation operator decides which data shall be used for any particular exercise.

Specific parameters or plans may be modified or exchanged readily, additional flight plans and exercise plans may also be entered directly into the system using the keyboard and EDD. It is possible to simultaneously assemble exercises from stored plans and conduct actual training.

Prepa ration time may be reduced considerably by using fast-time simu lat ion at speeds up to five times actual speed. For detailed examinatio n simulation speed may be reduced to two-thirds actual speed. Upon completion of the preparation phase a high speed line p rinter provides a print-out of the complete exercise.

Not only Sophisticated but also Comprehensive The SATS facility is only one part of the training centre.

Also avai lable is a less complex area radar simulator using analogue computing methods and partially synthetic displays. Two aerodrome control-tower simulators are also provided ; in one a realistic Tower overlooks a model airfield w here " pi lots" fly model aircraft around a c ircuit as requested; in the other, overhead back-projection is used to produce a large picture of an airfield together with aircraft positions. Jn both the emphasis is on providing the student with a fully realistic control-tower layout.

The size of the Sturup centre can be judged from the peripheral faci lities. There are 34 two-frequency R/T-, 30 interphone-, 43 telephone- and 39 instructor tel epho~e stations. Communication facil ities comprise therefore, in other words: 34 positions with simulated radio-telephone (2 frequencies) , 30 positions with intercom (10 chan~els) .

43 pos itions with operational intercom, and 39 positions with instructor's intercom.

Sweden 's air traffic cont rollers can feel justly proud of having one of the most up-to-date ATC train ing establishments in the world.

23

Ferranti simulators put years on your student controllers

.......

...

~-

' ·-.. -........___ ...,... ··-----·-··--·

·-

--

Our ATC training simulators give controllers the experience they need to do their job - before they start doing it.

This is due to the detailed and comprehensive realism of Ferranti digital simulator systems.

The trainee controller's radar displays are identical with those used operationally, and simulated RT and intercom are provided. With this equipment the trainee learns how to cope with aircraft identification, separation, sequencing, the allocation of levels, routing, stacking, and other problems.

Ferranti have studied air traffic control in depth and have an understanding of current and future needs as realistic as the simulators themselves. We know the economic importance of

handling heavy air traffic with minimum delays.

It's hardly surprising therefore that Ferranti ATC simulators have been chosen for the largest and smallest requirements and are currently in service or on order for London Heathrow, Amsterdam Schiphol, Rome Ciampino, Copenhagen Kastrup, Taiwan Taipei, Sydney Australia, and at the College of Air Traffic Control at Hurn. And a Ferranti simulator is used at the .CAA ATC Evaluation Unit for their real time traffic control studies.

Ferranti Limited, Digital Systems Division, Western Road, Bracknell, Berkshire, RG12 IRA. Telephone: 0344 3232. Telex: 848117.

FERRANTI

The real thing in simulation

International Law - Part X

by E. McCluskey, IFATCA Standing Committee VII (Legal Matters)

International Institutions (3): International Civil Aviation Organisation The subject of this article is well known to air traffic controllers but it is necessary to include the International Civil Aviation Organisation in any series on International Law leading to a fuller discussion of Air Law. Like the International Court of Justice, ICAO is a specialist organ of the United Nations Organisation coming under the general heading of Transport and Communications. This article deals with the aims and functions of ICAO, its structure and the general idea of the code of the air. In a later article we shall have to return to the last facet in more detail.

The International Civil Aviation Organisation was set up by the International Civil Aviation Convention of December 7th 1944, better known as the Chicago Convention. The Convention was to supersede the Convention on the Regulation of Aerial Navigation which had set up the International Commission for Air Navigation. Older controllers will remember working for ICAN standards even into the 1950s.

The aims given to ICAO were: 1) to ensure the safe and orderly growth of international civil aviation throughout the world; 2) to encourage the arts of aircraft design and operation for peaceful purposes; 3) to encourage the development of airways, airports and air navigation facilities for international civil aviation; 4) to meet the needs for safe, regular, efficient and economical air transport; 5) to prevent economic waste caused by unreasonable competition; 6) to ensure that the rights of contracting States are fully respected and that every contracting State has a fair opportunity to operate international air lines; 7) to avoid discrimination between contracting States; 8) to promote safety of flight in international air navigation; 9) to promote generally the development of all aspects of international civil aeronautics.

ICAO is entrusted primarily with specific functions relating to safety standards and the provision of adequate technical facilities for air navigation. In effect, these are technical rules but it is because certain rulings made by ICAO must be accepted by contracting States that technical rules become part and parcel of International Law with all the requirements of the rules based on the principles of law which we have already seen in previous articles, e. g. good faith, reciprocity, etc.

ICAO keeps up to date the technical annexes to the Convention which constitute the International code of the air. Thus aviation is one field where the law can be said to be relatively dynamic since updates are rather more frequent than in other codes. If ICAO thinks that airports or other facilities of a contracting State are inadequate to the needs of international air services, the Organisation may consult the State and other States concerned, with a view to remedying the problem. If the contracting State so requests, ICAO may provide all or part of the cost, also being able to maintain and administer any or all of the navigational facilities or to provide technical assistance.

Typical of maintenance of services by funding or otherwise are the North Atlantic Ocean Weather Stations and the

26

maintenance of certain services in Greenland while technical assistance is provided in many developing countrie.s including funding of training of personnel outside their home States. ICAO cannot operate air services nor fix frequencies of flights or rates. General agreement has ~ot yet been reached on the extent of foreign services putting down or embarking passengers, cargo and mail but some functions are given to ICAO by the Air Transport Agre~men~ and the Air Services Transit Agreement which were s1gne at the same time as the Chicago Convention. _ICA_O pub~ lishes information on the advancement of air nav1gat1on an the operation of international air services. Research ma.Y be conducted into all aspects of air transport and air navigation which are of international importance. Each c~n~ tracting State ensures that its international airlines file wit ICAO traffic reports, statistics and financial statements.

In order to achieve its aims, ICAO also may consult organisations such as our own, when expert opinion can further the aims of ICAO. IFATCA has achieved observer status at numerous ICAO meetings and by such contributions as the IFATCA thesis on Primary Radar Procedures, the Federation not only furthers the aims of ICAO_ bU~ makes through such studies a contribution to lnternationa Law. ICAO operates through the following bodies: the Assem; bly, consisting of all contracting States, which meets a least once every three years; the Council, which is the permanent body, consisting of the President and representatives of 27 contracting States elected by the Assembly for three year terms, and being responsible to the Assem~ly.

The subsidiary bodies are the Air Navigation Commission. the Air Transport Committee, technical divisions of the Air Navigation Commission, Regional Air Navigation Meetings, the Finance Committee and the Legal Committee.

The Chicago Convention provides that election of members of the Council shall give adequate representation to major aviation powers to States which make the largest contributions to the ~revision of facilities and to States ensuring representation of all major geographical regions of the World. The main sources of funds are the Stat~ forming the Assembly, the United Nations Special fun the United Nations Technical Assistance Programme an the States receiving technical assistance. t We have already mentioned IFATCA's contribution . ·n the t ech meal aspects of ICAO's work· it is hoped that 1 ' . ·on near future the Federation may also make a contnbuti .

d

°

to the purely legal aspects in presenting the case for Limitation of the Air Traffic Controller's Legal Liability. The ICAO Legal Committee is formed to develop particular cases in International Law and the question of Controller's liability is a special aspect which demands study.

The International Navigation Code of the Air is just as real as maritime codes of which we spoke in earlier articles. The Code is written in Annexes to the Convention which include standards and recommended practices and air navigation procedures. Annexes are adopted or amended by a two thirds majority of the Council. However they do not come into force if a majority of the contracting States

disapprove within three months o r a longer period if laid down by the Council. Standards are specifications w hose uniform application is recognised as being essential to the safety or regularity of air navigation. Recommended practices are s pecifications recognised as being desirable. The contracting States under the terms of the Convention must comply with the standards. The Coun ci l must be notified if they find it impossible to apply them. The contracting States must endeavour to confo rm to the recommended practices. In the latter case, States are invited to inform the Council of any differences between recommended practices and nation al practices especially where international knowledge of the differences is important to the safety of air navigation. Because of the great disparity in development and inability to comply with standards and recommended practices, so that misunderstanding does not occur, regional procedures are often found to be necessary.

It is in this aspect of air navigation that IFATCA has much to learn from its recent and new Member Associations from developing countries. In the past, because of the way IFATCA developed outwards from Europe there has been

a tendency in the Federation to think always in terms of sophisticated procedures. We must now look to ou r Member Associations particularly in Asia, Africa, South and Central America to keep the Federation in touch with the affairs w hich ICAO has to deal with from day to day. Th e more we appreciate the problems facing ICAO, the more ou r Federation can contribute to International Air Safety and International Law. But ICAO is not the only specialist Organisation of the UNO which affects the air traffic controller. In the next Article we shall remain in the sphere of Transport and Communications to look at the Inter-Governmental Maritime Consultative Organisation, the International Telecommunications Union and the World Meteorological Organisation.

For further study: Traite de droit aerien, Lemoine, pages 76-99, 136-158; Law of the Air, McNair, Kerr and MacGrlndle; International Law Association Report No. 45; Hague Recueil No. 81, pages 204-305: The Chicago Convention; Annexes to the Chicago Convention ; ICAO Bulletins.

ATC And The Aerial Photographer

by Ralph E. Kauffman, President, Abrams Aerial Survey Corporation, Lansing, Michigan, U.S.A.

I speak for a minority group, the aerial mappers, an unusual group in two or three respects. We are aerial photographers but not the large group of "scenic" photographers who stick a camera out of the window of a cub or a helicopter to make arty, oblique exposures of football stadiums, factories, shopping centers, and real estate developments. We are the engineering-related people who utilize $ 100,000 cameras to secure precise vertical photography as the first step of a complex procedure leading ultimately to the development of detailed maps and to the compilation of almost unlimited information about the surface and the subsurface of the earth, data required by engineers and planners for virtually every undertaking man needs to support his existence. we are a min ority group in the U.S. because our tota l air fleet numbers no more than 500, somewhat less than one-half of one percent of the total U.S. civil aircraft fleet.

In type, these 500 or so will range from single-engine, low and slow, to a few jets, but the majority are light twins operating within an altitude block of 2400 feet to 26,000 feet. A few will have minimal navigational equipment, while others will carry a considerable amount of exotic gear. A majority will be well-equipped by modern standards. A few of these 500 aircraft will be flown by young, relatively lowtime crews, but a great many grey-haired airmen are among the photo-pilots. The level of professionalism is very high.

This diverse group has one common characteristic. On any clear day, close to 100 Ofo of the group will be airborne from three hours after sunrise until three hours before sunset. At this point they become the air traffic contro ller's concern.

The controller's concern because, in the performance of their flight assignments, they must arrive at a predetermined altitude over a precise ground point, and from that

Aerial Photographer at the controls installation in a Beech G-18 aircraft.

of

a Wi id

RC-10 Camera

27

point they must proceed down a predetermined line to another precise ground point. Any variation in altitude, any deviation from the predetermined line and the mission must be aborted and a new start made. The controller's concern because such items as altitude and headings are matters they control in the interest of safety and efficiency.

Without getting into the technicalities of ,,photogrammetry", the science of making precise measurements from aerial photographs, I can say that the aerial photography we accomplish is part of a complex mathematical formula, and anything beyond the most minimal variation from the predetermined plan renders the photography useless and calls for another effort, which is an expensive matter to us and a complication to ATC. I said our group is unusual because we are not seeking some sort of blanket exemption from regulation. To the contrary, we want and need the protection the regulation has been designed to afford. What we seek is the thoughtful utilization of that regulation to achieve both safety and operating efficiency.

Very simply, and this is probably oversimplification, we believe our problem to be a communication hangup. Not a mechanical communication, but philosophical communication, which will see our air crews understand the controller's goals and which will see controllers understand what it is we are trying to do and why we must do it in a certain way in their airspace. An understanding as to why we must shuttle back and forth through TCAs at arrival altitudes or why we have to bisect departure routes at inconvenient

altitudes and at impossible times. An understanding right down the line to the individual controllers in the ATC system and the individual air crews in our group.

FAA Notice N7110.249 reads in part: "ATC facilities should strive to work out details to accommodate photographic missions ... we have requested that pilots say 'this is a photo mission' when contacting the ATC facility.

When the pilot commences the actual photographic run, every reasonable effort should be made to permit him to continue uninterrupted, that is, without changing heading or altitude. Should it be necessary to break him off the flight line, he should be vectored or cleared back into position for another run as soon as possible."

Our problem still is as critical as it was when the FAA Notice was issued. We are locked into a set of fixed criteria. Most of our activities are necessarily in areas where there are large concentrations of people. Most of our experiences with ATC are good experiences, but there are also less good experiences. What we seek is mutual understanding to help us accomplish a difficult job. We can do it within the system and through the controller's help with a minimum of confusion.

We don't regard controllers as unreasonable villains, but rather as the good guys who will help us if they can, provided they understand what it is we are doing. We don't regard the regulations and procedures as unreasonably restrictive but rather as the key to our orderly operations within the system.

Spotlight On A Corporation Member Stansaab Elektronik AB Stansaab Elektronik AB is a company with long experience, the foundation of which was laid in the 1940's when Standard Radio & Telefon AB started the development of advanced equipment for military radar surveillance centres. However, the company's present name was introduced in January, 1971, the ownership of Stansaab being equally shared between Swedish Development Company (SUAB), SAAB-SCANIA and Standard Radio & Telefon AB (SAT). On March 1, 1973 the SAT shares were taken over

by SUAB and SAAB-SCANIA who are now holding 50 % of the shares.

The company specialises in real-time data processing systems. Specialisation in real-time processing is a natural consequence of Stansaab's earlier experience in the area of Air Defense. Over the last 20 years the speed of aircraft and missiles has increased, reducing available decision time for counter-measures after radar detection of an enemy approach. In the beginning of the sixties, Stansaab secured the order for the radar data handling and presentation centres that were to be developed for STAil 60, the Swedish air defence surveillance system. The system requirements for STAil 60 demanded computer power of a new dimension. At that time reasonably priced computers, complying with the required real-time performance, were not available. A new computer system was developed,

28

resulting in the first generation of the company's Censor computers. These computers constituted an advanced and powerful real-time system which has since been further developed and extended into a complete data processing and presentation system.

Experience from the development of the first Censor

sy~tem which commenced in 1960 proved very useful and

t~i~ led Stansaab into civil Air Traffic Control. The first ~ivil system was installed at Arlanda Airport Stockholm. in 1964· It st·1mulated international interest as 'a forerunner of modern computer-based Air Traffic Control. The Stan-

s~a.b technique to provide air traffic controllers with a ~igitally .processed radar picture of the air space situation ~~· real~time was. i~itially regarded with scepticism. Today is philosophy is internationally accepted and in modern A}C systems, computers now automatically keep track of aircraft positions d .

• an present processed information in a form. adapted to the controller's demands. The company's continuous system d eve1opment has resulted in significant •• exports, and at the present time Stansaab is one of the co~pa~atively few companies in the world capable of dehverrng complete ATC data ha ndi"rng syst ems.

Censor 900, A Complete Information System Stansaab's principle product today is the Censor 900 Data System which includes powerful computers and a full range of displays and other peripheral equipment. Ex-

perience of several generations of computer systems and their applications provides the basis for Censor 900. The system is highly user-orientated and a design feature is its modularity of hardware and software design and its flexible ability to be configured for systems requiring multiple and simu ltaneous processing, which means meeting a wide variety of applications. Stansaab systems are built by modular units forming the Censor 900 system. The system includes two types of computers - Censor 932 for central p rocessing and Censo r 908 for communication processing and control. Both compute rs are modern and powerful for t heir respective purposes. Their performance becomes most effective when used in a total system concept owing to efficient adaptation between the various Censor 900 system elements.

According to requirement, a number of processors may be inter-connected, and in complex systems several computers may operate in parallel. Increased reliability is achieved by automatic switch-over between parallel machines. Several human operators and functions can simultaneously use one system without mutual interference. The Censor 900 series are easily adapted to the requirements of a particular custo mer. Stansaab, being a small company, believes it is more flexible than the industry giants, and better able to meet a one-off requirement for a customer.

The Censor 900 system also has a wide variety of equipment for man/machine co mmunication: radar displays, graphic and alphanumeric displays, radar extractors, data communication modules and other input and output devices.

Sta nsaa b uses Computers for a utomating

Production and Development Stansaab is an advanced technology company with a highly qualified engineering staff. They are particu larly proud of their use of computers for automating produc tion and development. The company has approximately one computer for every ten employees involved in manufacture.

Manufacturing is extensively automated and controlled by computer equipment especially developed within the company. For example, all co mputer circuit board assembly is computer controlled. The operator is provided with stacks of different components and a diagram of the order in which they are to be placed on the card; the computer then indicates which component to take next, and prohibits incorrect selections. All equipment, except some standard peripherals, is desig ned and produced in-house.

Wiring is simplified and more reliable due to the use of special computer-controlled wire-wrapping mach ines. Production facilities embrace all phases of electronics manufacture from one-off manufacture of special units to production runs of standard equipment, such as rad ar data displays. . . .

The company's labo ratories, extensively ra~1onalised, are responsible for equipment development, using advanced measuring and computer-aided desi~n t.e~hniques_. Special test centres are provided both for ind1v1dual unit testing and acceptance of complete operational systems. Research laborato ries and extensively automated component testing departments provide manufacturing support. All co mponents used in manufacture are tested on a 100 O/o basis on arrival at the factory and every unit is thoroughly tested in special test rooms before delivery. Considerable effort

Alfaskop 3500 Alpha-Numeric Data Term inal System

is expended in testing, both during and after construction, to eliminate infant mortality in systems.

The system department is responsible for development and plannin g of systems and application programming, using an in-house computer centre for program testing.

Comp lete systems are designed using Stansaab hardware and software modules. The system department frequently takes care of the management and coordination required for delivery of complete operational systems, so called turn-key projects. Software is developed for each system using keyboard and visual display units coupled to a computer on a time-sharing basis. Programs can thus be designed, edited and tested without resort to the tedious , timeconsuming and more conventional methods involving paper and pencil. Repeated trials on a full-scale computer are also avoided.

Alfaskop Alpha-Numeric Data Terminal System One of the major activities of Stansaab is the design and development of data terminals. Many business activities can be developed more efficiently if direct communication with a cent ral computer can be easily undertaken by relatively unskilled operators.

Stansaab is market leader in Sweden for data terminal display systems and a significant number of terminals is exported. Its alpha-numeri c data terminal system, Alfaskop, has been designed , as have all Stansaab's products. with great thought towards ergonomics. It was, of necessity. developed to cope with a wide variety of demands, as a low-priced supplement to the radar and graphical displays.

The display screen and associated Input keyboard have many appl ications as a means for direct communication between man and machine, which go beyond Stansaab's traditional applications. It has therefore been designed for coupling to any type of computer commonly used for automatic data processing in addition to the Censor computer.

The Alfaskop provides a clear and easily readabl e text on a large screen and yet is both small and light-weight.

It consists of a video display unit with a low-glare. ?in x 1Oin screen and high (50 Hz) refresh rate to minimise flicker. This unit, with up to 80 characters on 24 lines, can 29

The SATS civil simulator at Sturup Airport, Malmo, similarly caters for civil controllers (a full description of th is system is given elsewhere in this issue - Ed.) When the Eurocontrol Agency required a complex system for installation at Bretigny, outside Paris, Stansaab - in international competition, participating in an international consortium, won the contract to deliver the complete display equipment and large parts of the computer programmes. Apart from the training of air traffic controllers th is simulator is mainly used to simulate and test new types of ATC Centre operations and investigate air traffic p rocedu res.

Stansaab's Future

TAST _ Swedish Air Defense Simulator showing two of the 74 consoles

stand with or remote from an input keyboard and line printer for hard-copying of output. Although the Alfaskop has many applications throughout industry, Stansaab has found a particular market for it as part of an airline ticket-reservation system. Several thousand Alfaskops are already in use, including more than 1,000 with SAS. Alfaskops are also used in an installation in Switzerland, linking the ATC Area Control Centres at Geneva and Zurich in the transmission of flight-plan data. For each customer Stansaab develops not only any particular requirements in the hardware but also a f ull .range of software.

T AST and SATS ATC Simulators Air traffic controllers must be trained under fully realistic conditions without disturbing normal ATC operations. Highly flexible computer-controlled simulators have therefore become a necessity. Simulators are simi larly important for advanced studies of complex air traffic situations and of procedures at new airports and airways.

Stansaab has commissioned two ATC simu lators, one for civil training and the other for the military. The military simulator, known as TAST, was handed over in 1974 and is located at Tullinge, south of Stockholm. It provides full simulation for radar operators (trackers) and intercepter controllers. It is possible also to conduct counter-attack manoeuvres and tactical and defence studies. A total of 48 controllers in two sections can be trained. The system is built around a Censor 932 and a 908. The latter drives t he radar displays while the former deals with real time data processing. Emphasis is placed on providing the most realistic display possible. The simulation of 136 simultaneous aircraft movements, of seven different types, is possible. Th e capacity of the program disk store permits 50,000 movements to be used in various combinations du ring the exercises .

There are more than 100 displays in the system, including radar PPl s and graphic and alphanume ric presentatio ns. The software includes facilities for electronic countermeasures (ECM) and electronic counter-counter-measures (ECCM) si mulation in addition to general clutter and ~nd effects. Primary radar and synthetic information is displayed and the actions of each trainee are recorded. The instructor is able to intervene and replay instantaneously the exercise for an individual trainee and discuss and correct his actions without disturbing the instruction for other trainees.

30

Stansaab is a data system company and has chosen to work within special sectors of computer technique where, through a systematic development of knowledge and resources, a recognised position in the computer market has been achieved both nationally and internationally. For many years, work has been directed to the design of systems suited to operational requirements within application areas where fast information processing is decisive. For these applications, powerful computer systems are required which are capable of processing and displaying data in a meaningful manner in fractions of a second.

Community development will impose increased demands on industrial and commercial computer-based information systems for the efficient processing of vast amounts of data. With its backgrou nd and experience the company is well equipped to meet such future requirements. Stansaab policy is to identify those particular areas of data handling technology where in-house resources enable the company to specialise and to offer complete system solutions to customers. Stansaab intends to continue in this manner and to further consolidate the position so far achieved in the world market.

Stansaab has around 1000 employees -600 are engineers and programmers engaged in system design - and utilises an organisation especially suited to the administration of major system projects. All activities of development, production, testing and marketing are located in a single, modern factory at Jiirfiilla, near Stockholm. The annual turnover is approx. ÂŁ 13 million and it is anticipated that this figure will reach ÂŁ 40 million a year in the foreseeable future. Systematic work in the field of ATC has resu lted in export orders from Austria, Belgium, Eurocontrol, the Netherlands, the Soviet Union and Yugoslavia.

Stansaab says that it can plan the foreseen expansion because it concentrates on a few specialised sectors of the data-processing market, two of which have direct aeronautical applications. Marketing has been concentrated in Europe, with progressive expansion from a sound base in Scandinavia.

On Christmas Eve some years ago, the following message was overheard between the Tower and a KLM Electra, which had remained stubbornly in the hold at Garston after several aircraft had been diverted due to fog.

TWR : KLM ... you have been holding for one hour forty-five minutes ... are you all right for f uel?

KLM: Affirmative .. . it's the food and water we are worried about.

(Air way)

June 21 AT JFK*

by George C. Larson

J. F. Kennedy Airport

New York's John F. Kennedy International, a sprawling expanse that see ms awesomely large during any season, beco mes swollen in summer, like an overripe melon abo ut to burst with a surfeit of fat airplanes, pudgy tourists and stuffed terminal buildings. In summer, John F. Kennedy International sets itself to the task that it was designed for: to embark and disembark vacation passe ngers flying between various international destinations and the eastern United States. That design has now been overtaxed and stretched to its apparent limits in terms of how many people JFK can pass through its metropoli s of facilities.

The many growth rin gs you can discern in Kennedy's roundels of buildings, roads and walkways are matched by similar sign s of rapid growth in the organisation of th e airspace that surrounds this giant terminal. Let your eyes wander idly from the bird's eye-view airport diagram to the graphic representations of the four holding areas that serve Kennedy _ Empire, Southgate, Bohemia and Colts Neck and yo u will wonder why the physical airport ever impressed you so immense are the phantom castles and fortresses 0 ~ airspace that guard the outer rim of the New York TMA. Kennedy's ai rspace, in fact , looks like the old joke come true about an elephant bei ng a mouse that was designed to Government specifications.

If you are lucky and have a reason good enough to all ow you access to Kennedy Tower, the ~iew from the cab wi ll fill you with a sense of megalomania gone rampant :

?f

â&#x20AC;˘ This is an account of a day in the life cont~ollers who control the ai r t raffic on and around an lntern.allonal airport. Yes, your instructo r told you there'd be days l ike this, and now you are in the hot seat. This account was first published in FLYING Magazine.

JFK is the ultimate electric trai n-set. But it is also a vital o rgan w ithin this beast called air transport, and when, one night in June a year or two ago, all manner of things went wrong at Kennedy, the beast t urned on its smug creators.

June 21 begins w ith the ILS for Runway 22L out of service. Runway 22L is the shorter of t he two southwest-bound runways, its asphalt stretch ing 8,400 feet, and its lighted app roach extending some 3,000 feet farther. For days, an aged DC-3 operated by the FAA has been trying to test-fly the glide path for operation approval, but weather has obsc ured the necessary v isual cues that are pa rt of the surveying procedure. The watch supervisor at Kennedy Tower has duly noted t he fact of the glide path's absence in his FAA Fo rm 7240-4, Daily Record of Faci lity Operation.

Along with th at, he has begun the day with an entry at 0400z th at reads, " WX IFR, Average dep delay 1 plus 30, 7 waiting. Delay due WX. Have dep min on 22R; some ale electing to take it." An ominous pro log ue to what is to come.

Th e d elays stubbornly persist along with the poor weather until well aft er midnight, when the average delay d rops f rom over an hour to about 15 minutes. Runway 22R is t he only one with even departu re minimums, a condition that shows no promise of early relief from the t hree-knot southwest w ind.

All through the morning, busy controllers and ~qually busy pilots try to cope with the vagaries of electroni c g~ar and the willful weather. At a little after seven a. m., the glide slope fails on Ru nway 04R; as soon as it is fixed , the v'.sibility drops to a quarter and then to an eighth of a mi.le.

Th e twin Runway 13s, Left and Right, are closed for m~m­ tenance until four o'clock that afternoon. Lu ck ily, the wmd , at only three knots, allows a switch to the 220-degree run31

way, although pilots will be squeezing in with only a localiser to help them. At 11 o'clock, the outer marker to Runway 22L fails and the fourth busiest airport in the U.S. begins to work VOR approaches into its remaining runway.

Still, despite delays and occasional emergencies that upset the sequence, those who are stuck in the air and those who are stuck on the ground are managing to cope. The hours pass. At 1743z, or shortly thereafter, the Tower asks the Port of New York Authority to release Runway 13L-31R for operations; the Authority complies. ("This is Kennedy Departure Information Service with Information Whiskey.

Departure Runway 13 Right. Wind 190 degrees at eight, altimeter 30.11, temperature 67... Notice to airmen: Severe-weather avoidance routings are in effect over Huguenot. Departures inform clearance delivery that you have received Information Whiskey. BLEEEEEEEP.") Once the armada of aircraft can be readjusted to Runway 13, a move that involves every link in the chain of Air Traffic Control, from the approach controller to the ground controller, the airport will have a working ILS approach available, and that is becoming a more and more meaningful consideration as delays are just barely forestalled. ("One-Six-Nine, are you installed on Double :apa now?"

"Ah yes sir, t am." "Yeah, I can see your right turn on rad~r. Monitor Tower now, 119.1." "One one nine one, ger.") A threatening bank of fog lies over Jamaica Bay, :hich borders JFK on the southern extremity of the filled marsh that now supports its runways. With the peculiar sense of humour that navaids often display, the outer marker for Runway 22L resumes operating as soon as the controllers finish the switch to 13L. When some aircraft begin reporting that the 13L outer marker is no longer functioning, the impudent transistors no longer seem a laughing matter. The Kennedy Tower crew switches runways again, this time to the northwest-bound pair. ("Allegheny 567, are you behind a Braniff?" "No, we don't see any Braniffs here." "All aircraft on this frequency, the departure runway will be Runway 04L. Braniff 101, make a left turn on the outer taxiway, hold short of Kilo. Delete departure heading 165, Braniff 101.")

Sometime around 2000z, one of the controllers who has been working in an office on a level below the control tower cab looks out of his window at the gloom. A perfect IFR day, and what better opportunity to check out a young controller who has been waiting for a chance to demonstrate his ability to control ground traffic in IFR conditions. He calls the candidate, and they agree to meet in the tower cab in 15 minutes.

Kennedy airport's surface-detection radar-scope hangs from the ceiling of the tower cab, painting on its screen a lurid lemon-lime-coloured smudge of light out of which controllers claim to be able to derive the location of airplanes on taxiways. The new man goes up to study the ground situation. By the time his check-out begins, things are growing rapidly worse. ("Five-Eight-Zero Romeo Alfa, leared to land." "Romeo Alfa, thank you, we're inside the c k r now." "Five-Eighty Romeo Alfa, visibility now one mare ,, A d . quarter mile." "Roger, we'll tak~ .a look. . n one ~mute ) The I8 t er, "Attention all aircraft, visibility three-sixteenths. · t th 0 f ·1 visibility from the Tower goes to one-six ee~ a m1 ehardly worth measuring - and Runway 04L is below ta~e­ off minima: some aircraft are getting out, but the entire traffic picture at JFK is now complicated. by sev~re-weather avoidance routing made necessary by a lme of violent thunderstorms moving in from the west and southwest. The 32

tower supervisor notes in his log: "Arr are below indicating minima, RVR 04R one thousand feet, 22L same, below minimum." ("Eastern 64, Kennedy Tower, Runway 13L, wind 190 degrees at seven." "Okay, how's everybody been makin' out?" "Eastern 64, we've had several landings."

"This is Clipper 292, anybody missed yet?" "No, there's one aircraft ahead of you on approach; several aircraft were pulled out by approach control." "Okay.") Traffic restrictions are now holding three aircraft on the ground. All three have been waiting for 30 minutes, and Braniff 101 to Washington National is about to begin an ongoing delay that will last for hours.

As pilots begin to feel the squeeze between the turbulent squall line that is nipping at the edge of the holding pattern to the west and the crippling effect of below-minimum conditions at JFK itself, they begin to press the already harried approach controllers for alternatives. Following a wind shift to the east at a slightly zestier eight knots and the difficulty with Runway 13L's outer marker, the budding young ground controller, who is getting a real trial by fire, has nearly completed the awesome task of getting a two-mile line-up of aircraft backed up along the taxiway and on the boarding-gate ramps turned around and feeding into Runway 04. ("Uh, I believe you went just a little too far, 580. Can you make a one-eighty there at your present position?" "Yes sir. You sent us to the inner and we're still on the inner." "Uh, one moment please." (Possibly meant for intercom, but broadcast over the air) " ..• the inner here, uh, I don't know what he's doin'." "Five-Eighty Romeo Alfa, do not follow the Trans World 707. Hold your position.")

New York Ceritre now puts a halt to southwest departures. Coming at this time of day, when many westbound flights are scheduled, the halt soon snarls the system with the intermixing of aircraft on taxiways, some with clearances and some on hold. The departures that have been on line for Runway 13R have to be moved the two and a half miles-to Runway 04L in such a way that cleared flights can get around those that have had their clearances cancelled.

Could some of them be re-routed northwest? Not this day, for that departure corridor is already saturated with traffic from Newark and La Guardia. By a combination of re-routing and flow control, clearances are being given and departures made, but only with long delays.

On good days, JFK measures the separation of its arrivals and departures in seconds; when those seconds drag into minutes, the pile-up staggers the imagination. In the four holding patterns, all the levels rapidly fill. Controllers negotiate with each other over phone lines for extra levels into which they can insert arriving flights.

On the ground, when the weather holds below take-off minima for Runway 04L, some flights go to 04R and manage to get out. At six o'clock, there are 25 aircraft still waiting after 30 minutes. At half past eight, another hold is slapped on all departures because of system saturation, and "silent" clearances - those clearances that arrive at the Tower on a computer printout instead of over the phone - are suspended. Forty-minute delays, 30 aircraft.

There is nothing magical about the fact that flights are arriving with ceilings reported below minimum. The constant repetition of flights over the same route month after month bears fruit for all but the few who respond to a controller's weather advisory with, "but, uh, that's below minima". If the pilot grew up on Long Island, he is doubly blessed this night, for you may be able to spot a familiar checkpoint through a break in the overcast. ("There's the Cross Island

of departing flights now holding at the gates for more than Parkway. About three more miles. Beautiful, there's gotta two hours, the Tower runs out only departures, while arribe the Sunrise Highway there - I can see the Pizza Hut.") Aloft, anxious pilots are discussing the line of thunder- vals are forced to hold for 40 minutes. The departure delays are whittled down until they vary around an hour and a half¡ storms with controllers ("Any turbulence, Northwest 18?" inbound delays have suffered in the process and reach "No.pe, just heavy rain right now." "TWA 876, would you their peak for the night: one hour plus 30. advise hold there, or go elsewhere?" The grimvoiced ansIt will be some time before they get the 747 out of its wer: "Go elsewhere.'') Controllers offer the scant encourswampy resting place, but schedules thin out with the late agement that some flights have made it in all the way, but hours, and the average delay tapers off. When the tower the .combination of weather delays and the possibility of supervisor closes the daily log at 0415z on June 22, the getting trapped offshore by the advancing squalls is forcing localiser for 22L is out of service and the delay is back fuel decisions upon some flights. More than one diversion to an hour and 15 minutes, with 31 aircraft waiting. But begins to interrupt the flow as the captains make the hard eventually the bad weather moves on and operations return choice of taking a planeload of people to some city they slowly to normal. The 747 is pulled out of the mud, hosed have no intention of visiting. ("Allegheny 573 has solid IFR off and inspected while the landing is argued over. Evenrain and chop.'' "And we're gonna get shut off again her~ tually, the FAA's DC-3 will get around to surveying in the soon, sir." "Five-Seven-Three, give me your Newark weaglide path for Runway 22L. ther, please.") United 394 thinks it over and decides to try At JFK Tower, those controllers who have volunteered and shoot it. He is successful. So is the Allegheny flight. to stay on and help with the load finally leave for home.

What infinitely complex computations are taking place The young one, the fellow who picked this night to check within the minds of these pilots and controllers as they ride out his IFR-ground skills, has not only passed the test but out the worsening night? Each flight has its unique set of has aged quickly on the job. In the air, it has been a time conditions, particularly those of fuel, company policy, pasof tough decisions. Some who elected to try approaches senger mood and whether or not the captain can recognize may decide differently in the future, based on what they Rockaway in the rain. have experienced at JFK this night; others, who diverted, Difficulty in braking on the wet runways in the heavy may second-guess themselves into making a try for it when rain is an added consideration as controllers recite the they get their next chance to shoot an approach into Kenreported conditions for various types of aircraft. ("Braking nedy to scratchy minimums. June 21 at JFK is, after all, action good, Eastern DC-8, reported poor, 707.") A Luftbusiness as usual. hansa flight arriving from its transoceanic crossing is sent to a holding pattern that takes it into turbulence. ("Lufthansa 412, request another holding pattern." "Lufhansa, can you hang in there another 15 minutes? We hope to The U.S. National Transportation Safety Board has move you out in six or eight."). By nine p. m., the weather is urged the Federal Aviation Administration to abolish Spe200 overcast with a mile and a quarter in thunderstorms, cial VFR clearances and raise VFR weather minimums outrain showers and fog. On the ground, it's a one-hour-andside controlled airspace to that of controlled airspace. The . 40-minute average delay, with 40 aircraft holding. A light Board cited 44 fatal accidents in 1964-1972, which killed aircraft pilot patiently waiting for a break in the logjam 105 persons. Special VFR clearances were involved in finally decides to call it a night. {"We'll see you guys in the ¡ each case. Weather was the probable cause in one of the morning. Go ahead and cancel us - and good luck.") accidents and a factor in 38.

At one minute before 10 local time, a 747 inbound from In a letter to the FAA Administrator, the Board has Europe runs off Runway 22L. The Port Authority hurriedly pointed out that under current Special VFR, weather sends out buses after the crash trucks have felt their way conditions could be below the IFR landing minimums presacross the vast airport to the plane, which is now sitting cribed for an airline transport-rated pilot. But a student mired in mud off the left side of 22L. The passengers depilot, or a private pilot with low flight hours and no instruplane without incident, and all are off by 35 minutes past ment rating, could be granted permission to land during the hour. The airplane remains in position, though, its tail daylight with a ceiling as low as a 100 ft. if visibility were jutting into the flight path of Runway 13R, halting deparat least 1 n.m. Search and rescue, police patrol, firetures again. Departure delays now reach a peak of two fighting and other emergency operations could be conhours and 30 minutes, with 35 aircraft waiting. ducted under waivers of minimum rules, the NTSB said.

Just minutes prior to the 747's putting a lid on every(Aviation Week & Space Technology) thing, an aircraft has reported an explosive static discharge while holding to the west. There almost seems to be a The 20 U.S. Centres have been equipped with Power subtle shift of mood now. Controllers try to be even more ~onditioning Systems (PCSs). These systems supply power encouraging, obliging. ("People are making approaches; instantaneously and automatically when there is an interI'd say 80 to 90 per cent are making it." "We don't care; ruption of commercial power. The PCSs maintain constant we want to go to Boston.") When the word comes that this power during most critical periods - during thunderstorms giant airport has no operative landing runways because a when a power failure is most likely and the need of conjumbo jet has mired itself in the one location that can close ~tant power most urgent. Because the system provides down two directions at once, the requests for La Guardia instantaneous battery power and operates only when accome thick and fast. Some flights can land there, but the tually needed, a genuine fuel saving has been realised by four-engine stuff can't, and they get the bad news: All runthe conversion to the PCS. For example, at Kansas City, ways closed; add one hour to the estimated approach where the system had supplied essential power on 35 clearance. separate oc.casions by the end of last summer, this saving It is a short time before 22R is re-activated to handle has averaged 900 gallons of generator fuel a month.

(ATCA News Letter) arrivals and departures. To deal with the massive backup 33

Future Air Traffic Control· Systems (Ill) The Role of the Pilot in the Air Traffic Control System The British Air Traffic Control Systems Committee was set up In 1971 to consider and propose long-term planning concepts for a new ATC system. The Committee membership Is drawn from the Gulld of Air Traffic Control Officers, the Air Line Pilots Association, the Guild of Air Pilots and Air Navigators and the Royal Aeronautical Society. The Committee has Issued a preliminary report - comprising a sixteen-part comprehensive analysis of future ATC system requirements as seen by air traffic controllers and pilots. The contribution of this Committee Is believed to be unique in the field of aviation, in that it is thought It may be the first time such a system design study has been jointly undertaken by the principal users rather than by designers or researchers. The report crystallises the concern felt by the professions represented by the committee regarding the future In Air Traffic Control internationally during the remainder of the century.

In this instalment, the role of the pilot In the ATC system Is examined.

The Pilot The effectiveness of the pilot in his environment is largely governed by a consideration of three main factors or environmental divisions, namely, the medium, the total task, and the flight deck.

The medium, in broad terms, may be described as "the air" and involves its many characteristics known as "weather" and, less commonly, aerodynamically induced phenomena such as wake turbulence. It would seem essential to the efficiency of the ATC system that information on the medium should be commonly available to both the pilot and the contro1ter.

The total task of the aircraft commander has been classified under six broad headings, i. e. Command, Look-out, Flight Path Control, Engineering, Navigation and Communication, as follows: a) Command - this is a continuous function which begins with the routine preparation of all aspects of the flight and should require minimum direct action or intervention. However when problems occur this function may well assume major importance. b) Look-out - presently a continuous requirement, even in IMC (Instrument Meteorological Conditions), as a number of air-miss reports have shown. It is considered necessary to arrange other functions so as to permit such continuous look-out, until such time as the ATC system can provide a fail-safe separation service. c) Flight Path Control - in small unsophisticated aircraft this is the main physical task of the pilot. In the larger, more complex aircraft, this function is performed by an auto-pilot which must be programmed and monitored at all times throughout the flight. d) Engineering - largely a monitoring function until malfunctions occur when considerable time and effort may be needed to perform the necessary corrective or emergency procedures. . e) Navigation - depending on the nature of the flight and the equipment carried, navigation can re~~lre a large rt 0 f the total effort available by requmng frequent pa • • t re-tuning to point-source aids, m erpret at"ion or ·mt err~gatlon of area aids and the co-ordination of the navigation and flight path control (see (c) abo~e) .. f) communications - currently most commumcat1ons between the aircraft and the out~ide world are based on R/T (radio-telephony), predo~m~ntly betv.:een the aircraft and a ground station which 1s responsible for some 34

form of co-ordination of air traffic (ATC). Other communications involve non-ATC messages of an advisory or commercial nature, such as weather, aerodrome Information and company messages, and are similarly conveyed by R/T. The range of activity varies from the almost continuous ATC R/T of today to the intermittent requirements of the company.

Aircraft/ATC interaction routinely occurs in the Flight Path Control, Navigation and Communications aspects of the total task, but the other three aspects may each be the determining factor in the inter-relationship of the air traffic controller's and the pilot's tasks. Due to other flight deck considerations an ATC requirement for an immediate change of flight plan may be inconvenient or undesirable or even impossible or dangerous. Time for assessment of the total implication should be provided. A means of determining true message priority is required, particularly In times of high workload or stress, and different forms of presentation may be required for a) instructions, b) advice or recommendation, and c) information.

The flight deck of an aircraft comprises a very restricted area within which the flight crew must perform their many functions from fixed seat positions. With the advent of high performance aircraft and sophisticated equipment the tendency is towards smaller crews. This means that each crew member has to perform a greater number of functions albeit with less physical effort. It follows that all controls, instruments and displays must be easily accessible and should, Ideally, be grouped in a logical manner for interpretation and interrogation. Ease of access or operation should be relative to importance of function and, to a lesser extent, frequency of use. The following factors should be noted: a) Safety is always the first objective and therefore first ~9ttty should be given to the location of flight controls and emergency controls on the flight deck. b) Navigation controls and displays must be prominently placed, particularly in aircraft without specialist navigators. c) Communications control units must be readily available for quick and easy operation to meet the requirements of ATC. d) Historically, all communications with ATC have been either by live voice (R/T) or by WIT. The future will demand automatic data transfer and the transmission of information and/or control instructions via alpha-numeric displays or other devices.

The location of displays and controls on the flight deck and allied matters, such as the design of attention-gaining methods, message priorities, readability in all external and internal light conditions and storage or hard-copy requirements, will all require careful thought if the benefit of improvements in the ground element of ATC is to be fully realised.

In summary, the pilot's environment is varied and everchanging, but the effective size of the flight deck remains the same and is largely determined by the length of a man's arms. A more sophisticated ground Air Traffic Control system will have to be complemented by the provision of equally sophisticated airborne equipment which can be used by the pilot without interference with his other functions. As with the controller, considerable weight must be given to the psychological and organisational factors affecting the pilot's environment. The need for the safe integration of all pilot activities, including those arising from the Air Traffic Control requirement, is not always currently appreciated. This aspect and a fuller discussion on the Pilot's Environment is dealt with in the chapter which follows below.

Human and Environmental Considerations - The Airline Pilot's Viewpoint Introduction The human and environmental (ergonomic) factors affecting the efficiency of the airline pilot within the system are discussed under the broad headings of: -a) The Context - the relationship between the pilot's overall operating function and the sub-function of operating with the assistance of the Air Traffic Control system, although having to accept the constraints of that system. b) The Equipment - those factors directly concerned with the design of the equipment with which the pilot Is expected to carry out the above subfunction. c) The Ambience - those factors which affect his efficiency as a human being concerned with the overall tasks of working on an aircraft flight deck. d) Job Organisation - those psychological and organisational factors which can affect his performance as a worker.

In any consideration of the future ATC system many lessons can be learned from a critical examination of the present environment. It is necessary to point out that many of the deficiencies of present ATC systems are of an international character and stem from the fact that these "syste~s" have grown up more like Topsy than to any preconceived total system design. The result has been to pass on so.me of the problems experienced on the ground to the . flight deck, bringing a confusion of regulation and e~u1pment dependent upon the degree of "control" exercised by individual States.

The Context . T~e duties of an aircraft commander have been classified â&#x20AC;˘~to six broad task areas, namely Command, Lookout, .Flt~ht Path Control, Engineering, Navigation and Communication. The objective of the aircraft commander is to carry out each particular flight to the highest possible level of safety, with the subsidiary objectives of passenger comfort, keeping to schedule, achieving operating economy and

minimising environmental disturbance to the general community.

The operating functions of a pilot imposed by the necessary requirement to adhere to the constraints and demands of the present Air Traffic Control System cannot be classified exclusively under any one of the six task areas listed above, nor any one of the objectives listed above. Instead, the requirements of the Air Traffic Control System are encountered in all six task areas, and affect the achievement of all four objectives. Because of this pervasion, any tendency in the development of ATC systems and procedures to assume that, for all practical purposes, the sole task of a pilot is to follow tactical ATC instructions is quite unacceptable. At present, due to factors such as an unsatisfactory airspace configuration, inadequate navigational capability and significant variations in aircraft performance during climb-out, it is inevitable that ATC intervention in order to give changes of routeing, altitude, etc., sometimes occurs at times highly inconvenient to the pilot. Any system which embodies such procedures, particularly in the early stages of flight, should be avoided at all costs.

It should be recognised by everyone involved in ATC planning that, whilst the requirements of the Air Traffic Control System are an important part of the total aircraft operation, only occasionally should they-.91ve rise to the dominant activity in any particular phase of flight. Consideration of the duties and objectives of an aircraft commander as outlined earlier should enable the relative precedence and timing of ATC functions to be determined for each phase.

The Equipment It is considered that the task of the pilot in relation to the Air Traffic Control System is twofold: a) Communications - the reception and acknowledgement of ATC messages; b) 4 -D Navigation - the control of the aircraft to achieve the ATC clearance.

Communications It is mentioned elsewhere in this Report that the exchange of routine information within the system should be automatic, using established principles such as data link and SSR, with voice communications in a supplementary role. The following basic pilot requirements apply: a) Automated communications must produce an overall improvement in the air/ground communications service to the pilot. b) Automated communications must decrease the overall pilot workload. c) There are five basic categories of message, and they should be handled as follows: i) Emergency Messages. These should be by means of pilot/controller voice communications and not by using the automated communications system. In an emergency situation, the automated system, in addition to continuing to handle routine air/ground data, should also transmit a signal indicating an emergency condition, receivable by ATC in less than 10 seconds. ii) Operational messages requiring immediate response or action by the pilot. These should be presented directly to him by suitable visual means and also, under certain circumstances, by synthetic voice, if

35

using pre-planned non-conflicting three dimensional flight and when this method is proven to be acceptable paths, together with limited speed regulation within prefor airborne use. determined ranges when necessary. The following basic iii) Operational messages which do not require immepilot requirements apply: diate response or action by the pilot, e. g. meteoroa) The three dimensional accuracy and the reliability of logical and AIS (Aeronautical Information Service) the automatic pilot/area navigation equipment must be information. These should be presented in an easily entirely within the performance limits specified for the accessible location which will not cause distraction. system. iv) Non-operational messages, i. e. connecting passenb) The quality of "the ride" must be improved over present gers, catering uplifts, etc. day VOR coupling, which is seldom used because of its v) Air-derived information of a navigational or meteororoughness .. logical character, e. g. position reports and in-flight c) The route details should be fed into the navigation comwind/temperature data. These should be transmitted puter from time to time directly from a data store. The automatically machine to machine. insertion of waypoints by entering co-ordinates via a d) The system should be capable of producing the messapush-button keyboard should be a fall-back procedure ges referred to in (c) (ii), (iii), and (iv) in hard copy rather than standard practice, because of error risk and form. time taken. e) Pilot input/output devices should be simple and selfevident to operate and interpret, particularly those d) It will be essential to provide an appropriate feedback to associated with the messages referred to in (c) (ii) the pilot of aircraft position in relation to its cleared flight path in both azimuth and elevation, e. g. by a above. f) Provision must be made for immediate transmission moving map display. The display must also have faciliof an indication that a distress situation exists (see (c) ties for the checking of stored data, look-ahead, etc. (i) above). This should be triggered by a single action The display must not be categorised as an allowable deficiency item. pilot input. g) Integrity of information interchange should be ensured The normal use of the above equipment must be desigby a suitable system for automatic detection and ned by pilots, engineers and ergonomists so as to achieve correction. Until this integrity is achieved, messages of a reduction in workload when compared with the present type (c) (ii) must be acknowledged in a verified readsystem of beacon tuning, track selection and heading control. back form. Initially, this may require voice communications. h) Provision should be made, in both ground and airborne Location of Navigation and systems, for automatic warning in the event of malCommunications Equipment function of any significant element of the overall system, The control panels for the area navigation equipment, and, if necessary, for the reversion to voice communications by the affected aircraft and ATC unit. the Moving Map display control panel, and the Automatic i) There should be no incompatibility of equipment - that Communications control panel should all be located so is, the most advanced airborne equipment must btf:-.. that~thay can be used by any crew member. (As has occurcompatible with the least advanced ground equipment red with aircraft currently fitted with triple I. N. s., this is and vice-versa. achieved by the facility of remote operation, whereby any j) Any automatic selection by the ground station of airof three control heads can be used to control any or all of borne frequencies should be confined to transceivers the three navaid units.) The Moving Map display itself, and used for communications purposes (i. e. not for naviga- the communications printer/display unit should both be tion purposes). There must always be a readout on the located where they can be read by any forward-facing crew member. flightdeck of frequencies so selected. k) Information received on the aircraft equipment should be displayed until cleared by the pilot. Any messages The Ambience subsequently received should then automatically, and The following factors are considered worthy of mention successively, be displayed until the backlog is cleared. under this heading. They are nearly all predetermined by I) Pilot messages (apart from (f) above) should be transconsiderations other than those of Air Traffic Control, but mitted in a "compose, inspect, amend if necessary, nevertheless are of considerable importance when assessing transmit" sequence. the factors likely to influence the pilot's performance in m) The type of display required for the passive reception response to ATC system requirements. of information, as distinct from data requiring challenge Noise Level. Noise arises from three main sources, i. e.: and response, could well be different - or a comproa) Aural warning devices. mise combination may be needed. b) Aerodynamic and System noises, which result from the The overriding consideration in all the above questions pilot's workplace being located in a moving aeroplane should be to ensure that the pilot is not given a major conrather than an ideal "office" location. trol task which may encroach on his attention to the primary c) Headset noise, wanted and unwanted communications, task of operating the aircraft, or which may increase cockintercommunications and background noises. pit workload. Therefore, all the ergonomic aspects must be Whilst System noise has reduced in recent years (inoptimised. cluding power plant systems) the aerodynamic noise has increased with increasing IAS (indicated airspeed) and the 4-D Navigation net level has remained much the same. It is considered still to be too loud for optimum human performance, even It is mentioned elsewhere in this Report that the system when wearing conventional headsets which act as earmuffs should be based on airborne navigation in four dimensions,

36

16th Annual Conference ~ International Federation of ~~) ._.,...i""j..,(.,, .......Y:""'I."""'~ ..

Air Traffic Controllers Associations

E

N ICOSIA . C Y PRU S

NICOSIA 25th-30th April 1977 General Information Location The Nicos ia International Conference Centre. (near Hilton Hotel).

Official language English Registration fees (per person).

Participants C ÂŁ 15.Accompany ing persons C ÂŁ 10.These fees cover: Participation in the Professional Sessions Receptions, local Transportation, Lunches, Coffee-Breaks , Social Events, Ladies programme.

Whole-day Tour including lunch, kindly offered by Cyprus Tourism Organization.

Ladles' Programme In addition to the general social activities to which the accompanying ladies will participate, a diversified program will be arranged for them during session time.

Secretariat: 16th Annual IFATCA Conference CYATCA, Civil Aviation Nicosia - Cyprus " The kidnapping of Gany medes" . One of the fin e mosaics covering the " House of Dionysos" at Kato Paphos .

Provisional Time Table Sunday

April 24, 1977 Arrival of Partic ipants Registration Press Conferen ce Monday Apri l 25, 1977 Reg istrati on Official Opening Working Sessions Social Eve nt Tuesday April 26, 1977 Working Sess ions Social Event Wednesday April 27, 1977 Wo rking Sessions Evenin g at Leisure Thursday April 28, 1977 Working Sessions Social Event Friday April 29, 1977 Technica l Presentation Final Sessions Banquet Saturday April 30, 1977 Whole- day Excurs ion Tour

Temple of Apollo, who was the City-God of Curion. The temple was bui lt in his honou r some 2 kms West of Curion City.

37

as well. Due to the ad hoe system of today, radio telephony has now become virtually continuous on the main routes across Europe, and at most international airports in Europe.

This continuous conversation requires continuous pilot listening and thereby intrudes upon other tasks, especially cockpit checks and drills. A high R/T level indicates to many pilots a low level of success at airspace and procedures organisation by the regulatory authority. The efficient pre-planning of operations would eliminate R/T saturation when used, inter alia, with a self evident ATC display system on the ground.

Temperature, Ventilation, Humidity. Modern aircraft airconditioning systems provide an excellent working environment in respect of temperatures and ventilation rate, especially as it is usually under the direct control of the user. However, on very few aircraft is the humidity controllable; it is often extremely low, requiring fluid intakes of up to one pint per hour to replace body losses.

Altitude. At the present time the cabin altitude during the cruise phase is usually about 7500 feet. The reduced oxygen level may necessitate additional breathing to achieve the required oxygen intake, and may reduce the pilot's performance from the ideal.

Lighting. The lighting levels in the cockpit will of necessity be far from the ideal for the ATC-dominated tasks, such as control of area navigation equipment, reading of automated communications and monitoring of Moving Map displays. The lighting levels are determined by the need for external visibility during night-time low visibility approaches, at the lower end, and by the requirement to avoid temporary blindness following a lightning strike on the cockpit screens, at the bright end of the scale.

Vibration. The presence of cockpit vibration during turbulence reduces the ability of the pilot to carry out both visual and manual tasks, including writing. This factor has increased somewhat with long-bodied aircraft, and difficulty in reading instruments is sometimes encountered in turbulence which, from other points of view, would be regarded as very light.

Confinement. The cockpit is a very small working space.

The combination of closeness to one's workmates, lack of freedom to even stretch one's limbs, continuous wearing of seat harness, inaccessability of toilets (plus waiting time!) and the general closeness of objects (thus precluding focussing of the eyes on distant objects), may at times cause a performance loss from the optimum.

The combination of the above factors -results in a far from ideal working ambience. There is little that can be done to improve them significantly, though small changes will occur in the normal course of progress. It is important to realise that the ambience of an aircraft flight deck is considerably inferior to that in, say, an electrical power distribution control room. The effect of the above factors on the pilot's performance, compared with the same pilot's performance in conditions of ideal lighting and humidity at sea level, in a vibration free, open plan, soundproofed area should be taken into account when designing the cockpit interface equipment with the Air Traffic Control System.

Psychological And Organisational Factors It is essential that any Air Traffic Control System produces a "safe, orderly and expeditious" traffic flow.

38

Pilot anxiety leading to reduced performance will result unless the system appears to be safe to the pilot. The target level of safety must be seen to be met, not by results (which are retrospective) but by the ability of the system to inspire the confidence of the user pilot. Operational safety depends upon not only protection from collision but also upon such environmental factors as turbulent wake and the ability to deviate around severe weather without a reduction in separation standards. Currently, the non-availability of weather information on modern ATC radar displays often leads to the pilot being required to choose between ATC requirements and those described earlier in this article when the objective of the aircraft commander was outlined (highest possible level of safety, passenger comfort, keeping to schedule, achieving operating economy, etc.)

Anxiety about the safety of a flight can also arise fro_m the different operational criteria applied by the State and the pilot (following his company directions). For example, despite some well-known anomalies between the State's and operator's minimum safe altitudes, it appears that ATC units increasingly expect aircraft commanders to comply unfailingly with clearances based on the State's (usually lower) margins.

Any lack of orderliness about the system will manifest itself in reduced system performance on account of, inter alia, increased aircrew error factors. As stated earlier in the Report, the system must be a strategic one, requiring the minimum (if any) intervention in normal operations.

Frequent intervention by ATC is an indication to the pilot of a lack of orderliness, and introduces anxiety, which can lead to increased error proneness at a time when error-free action is most required. As an example, last minute, and sometimes apparently unnecessarily late, instructions to the pilot to expedite take-off or, during landing, to clear the runway at a specified turn off, can lead to a reduction in safety. This is because the pilot, having exercised his command functions (earlier explained under the objective of the aircraft commander) and briefed his crew accordingly, could find himself committed to an unexpected and unplanned pattern of events.

Any unexplained delay found once engine-start approval has been given also indicates to the pilot a deficiency somewhere in the overall ATC system, whether due to a failure in the ground organisation, aircraft malfunction or other unpredicted causes. To alleviate this concern, if the system is to be affected during normal operations by lack of airspace, equipment, runway capacity or any pre-notified restrictions, then the delays should be absorbed prior to engine-start whenever possible. In-flight holding can appear to be an indication of the inability of the system to determine its own optimum flow rate, and thus once again causes anxiety to the pilot. As a normal procedure, the reasons for any delay should be conveyed to the pilot as soon as these are reliably ascertained. Generally, apart from acceptable speed adjustments, in-flight delays should not occur, unless there are circumstances which defy prediction.

Despite the desired lack of intervention by ATC, the pilot can become disquieted by a sense of isolation which results from long periods of absence of voice communications.

Airports And Their Control Towers (5) Tulsa Tower, Oklahoma

Rockwell International Ghost El iminator System at Tulsa Tower.

In recent years, the proliferation of high-rise co nstru ction around airports has produ ced increasing problems with radar beacon sig nal reflection s. Structures aro und an airport which fall into the path of the radar beacon system cause false returns on radar screens (so-called "ghostin g effect " ). Signals from the airport ground radar installation trigger responses from transponder units carried in the aircraft and enabl e a specifi cally coded identification to be di splayed on th e ATC radar scopes. Since the system is dependent on the receipt of electromagnetic energy by the g round rada r ante nna, it is susceptible to refl ections in much the same manner that various interference so urces cause " ghosting" on television screens. The basic cause of t he radar ghosting in a particular direction is that electromagnetic energy returning from an aircraft can also be reflected back by a stru ctu re near the radar unit. Th is causes the radar scope to pick up this weaker but evident false image of th e same aircraft.

At Tulsa A irport, the north wall of the FAA control tower was c lose enoug h to the beacon a ntenn a to become a troublesome sou rce of ghost targets. The geometric relationship between the Tulsa co ntrol tower and the radar installation location c reat ed this "ghosting effect" on th e radar scope. When an aeroplane was approachin g within one particular scanning area of the radar, the north wa ll

of the control tower wou ld receive and reflect the s ignals being t rans mitted by the aeroplane to the rad ar scope identifying its locat ion. The T ulsa Division of Rockwell International then came to the rescue with the development of an electromagnetic-energy-absor bent material called RIGEL. The name stands for Rockwell International Ghost Eliminator, and the honeycomb material co mes in 3-foot by 9-foot panels. By placing panels made of RIGEL on the particular structure w hi ch is reflecting the s ign als, the ghosting is eli minated since the panels absorb rather than reflect the signal. .

In the test programme conducted during 1974, six ve.rtical rows of RIGEL panels were installed in louvre fashion o n the upper 55 ft of the north wall of the contro l tower, as shown in th e photograph. This wall accounted for . ¡ d by the radar 70 per cent of the interference experience . to the rotating . I d contro llers. The panels are perpen 1cu ar . . across the tower radar antenna as its field of view sweeps the development t d t wal l. The new material can be equa e o of the fine tuner on television sets as far as the results on t he radar scope are concerned.

Technical Description RIGE L is a highly efficient passive ene rgy conversion system which converts electromagnetic ene rgy (radar 39

waves) to thermal energy (heat) in much the same way that a microwave oven heats food. The RIGEL components form a system which is precisely tuned to maximise the conversion of the impinging electromagnetic radar waves to a current flow within the electrical component sheet. The electrical resistance characteristics of the component sheet are such that the current flow is then dissipated as heat to the surrounding atmosphere. The efficiency of the system is a function of the integration of the electrical component sheet chemical formulation and pattern as well as the dimensional properties of the system. The selection of the specific physical characteristics is, in turn, dependent upon the operating frequency of the radar.

The induced heat levels are, of course, much lower tha.n those involved in a microwave oven. The radar power is dispersed so that the energy converted to heat by the RIGEL panels at the Tulsa installation will create a temperature rise, on an average day of less than .0002 F. A RIGEL panel is 1.62 in thick, and maximum dimensions are 10 x 4 ft. Basic weight is 1 lb/ft2; installed weig.ht with fittings in the Tulsa case was 1.5 lb/ft2. The material is available in 11 different colours; according to Rockwell, it complies with US building code requirements, is moisture sealed, ultra-violet protected and resistant to ice and snow.

Study Programme Testing of the material was performed with the cooperation of the Tulsa Airport Authority, the Tulsa Control Tower and Airways Facility Sector of the FAA and the ~38th Tactical Fighter Group of the Air National Guard.

A radar interference region was resolved in the Tulsa International Airport Control Zone near a radial of approximately 57 degrees from the VOR site. The geometric relationship between the radar installation and the control tower resulted in a situation that when the radar antenna was scanning the 115 degree radial, part of the radiated energy was being reflected back along the 57 degree radial. Because of this effect, an aircraft flying the 57 degree radial would also appear in the system as an aircraft flying the 115 degree radial.

These problem characteristics were definitised and an electromagnetic energy absorber design was formulated.

Precisely controlled evaluation flights were conducted using F-100 aircraft prior to installation of the panels and the transponder reply signals received by the ground beacon antenna were recorded on magnetic tape and subsequently processed by the FAA computer facility to provide a record printout of ghost-image occurrences as a function of altitude, distance, and time. Identical flights were conducted after RIGEL installation.

Based on the flight test data obtained during the test programme, test results showed that the RIGEL panel installation virtually eliminated the occurrence of ghost images from 57 degree radial traffic above 2,500 feet caused by the north wall of the control tower over the fullaltitude range spectrum of interest. The work load on the ATC monitoring systems is thus reduced and operating effectiveness improved.

Costs of the Tulsa installation worked out at$ 14 per ft2 ($ 150 per m2), with a further $ 6.30 per ft2 ($ 67.50 per m2 ) for installation. The company envisages costs for future installations as $ 6.500 fixed costs plus $ 14-17 per ft2 ($ 150-182 per m 2 ).

40

Brief Items The reporting of incidents and defects affecting the safety of British registered public transport aircraft over 2,300 kgs has been made mandatory in line with the practice already followed in some other countries. Worldwide experience of accidents has demonstrated that a number of them might have been avoided if operators had been alerted concerning previous relevant occurrences. Until recently the reporting of incidents and defects in the United Kingdom had been on a voluntary basis and although the response was good it was felt that a fully comprehensive reporting system for all such occurrences would help further to improve Britain's air safety record.

The Mandatory Occurrence Reporting scheme requires aircraft manufacturers, airline operators, pilots, air traffic controllers, engineers and aerodrome personnel to report to the Civil Aviation Authority within 96 hours any occurrence which has endangered an aircraft or, if not corrected, could have endangered an aircraft.

The names of individuals sending in reports will be kept confidential, unless disclosure is required by law or the informant gives consent. This is to encourage all who are employed in civil aviation to give timely information which might help to make flying even safer. All reports will be processed by a newly set up Safety Data Unit and fed into a computer which has been programmed to 'file' the reports on a cross indexing system. As the bank of reports builds up, it will be a relatively simple operation for the computer to search its store of reports to identify any history of occurrences which have a similarity so that these can be analysed by the Authority's safety experts to see what action might be taken.

(Air way)

Reporters from both CBS and a Canadian TV network have been interviewing and filming controllers at Chicago Centre and O'Hare Airport. Coverage dealt also with medically disqualified controllers and interviews were actually conducted with the physicians involved. A number of the latter said they would not be controllers for any price.

(PATCO Newsletter)

The Golden Headset Award goes again this issue to one of Sydney's most successful entrants.

Acting as CMC, our intrepid controller received a flight plan from Nowra for a cross-country exercise involving a Skyhawk. The plan contained one or two anomalies, so he rang Nowra to clarify the situation. After these had been resolved, he then said, "Oh, by the way, where is this place, HY?" "Why, Hay, of course," came the quick reply.

"Ah, yes, well you'd better remind the pilot that he has to pass Hay by the last light."

"Roger."

The Nowra controller hung up, and mulled over the requirement for a minute. Last light requirement for a Skyhawk cross country first thing in the morning? Back into the Sydney CMC "About this last light requirement on the Skyhawk cross-coun ... " "Yes, yes, long standing procedure ... Make Hay while the sun shines!"

(Cocodoodledoo, Sydney)

Stresses Of The Air Traffic Control Officer (Latest Developments) Report On The Second Manchester Symposium

by V. D. Hopkin

On April 10 and 11, 1976, a Symposium, supported by positions, noise and poor seating. Attitudes of management Geigy Pharmaceuticals and organised jointly by the U. K. and controllers' Jack of involvement with management Guild of Air Traffic Control Officers and the Department of decisions could also induce stress. Dr. Maxwell emphasised Postgraduate Medical Studies of the University of Manthat the purpose of annual medical examinations was to chester, was held at the University of Manchester, on the detect the onset of illnesses and to keep controllers at theme of "Stresses of the Air Traffic Control Officer". work. A problem was to define the circumstances under The Symposium was the second on this topic following a which certain normally unharmful stresses could become successful earlier symposium in 1973 with the same organisufficiently acute to be harmful.

Mr. L. W. Curry, the Master of the U.K. Guild, presented sation and support. On this occasion, more emphasis was a paper on behalf of IFATCA. This was a condensed verplaced on relevant factual evidence, and a broader persion of a paper by Sqn Ldr B. L. Watkin of the New Zealand spective was provided by invited speakers from overseas.

Association and stated a controller's view of the sources The Symposium was introduced by Dr. N. C. Brown, of stress in his work. The fact that this paper aroused conChairman of the Medical Advisory Sub-Committee of the siderable critical comment illustrated the problem of underU. K. Guild, who described the links with the previous standing the nature of stress and showed how important it Symposium and its success in fostering greater underwas to insure that all points of view received a hearing. The standing between the controller and his medical adviser.

IFATCA paper was critical of many management proceThe intention was to give each a fuller understanding of dures and decisions, and viewed these as a main source the role, the work and the problems of the other. Whereas of stress, frustration and resentment. Incidents of lack of the first Symposium had established that stress was a understanding were cited, and the paper enumerated a very problem in Air Traffic Control, it was hoped that the second large number of sources of stress, covering the air traffic Symposium would reveal more on the nature and magnicontroller's job itself, his conditions of employment, and the tude of the problem of stress in Air Traffic Control. impact of extraneous sources of stress such as domestic The opening address was given by Group Captain Douglas Bader of the U.K. Civil Aviation Authority. Having or financial crises. This raised a theme which recurred several times - namely the complex nature of the concept mentioned that an aim of the Symposium was to engender ·discussion on the topic, he contributed some stimulating of stress and its numerous interacting sources. The IFATCA and controversial remarks which eminently succeeded in paper, while presenting a comprehensive summary of the this purpose. He noted that problems of stress were· seen views of many controllers, nevertheless 10w some impreswith pilots, and encouraged advanced knowledge and dission that it registered complaints rather than made concussion of problems of stress among controllers, who had structive proposals, and perhaps would have been more a highly responsible job. Mentioning that many factors appropriate at a controllers's conference than at an interincluding domestic and financial worries, could produce disciplinary forum. It also tended to imply that the postucomparable effects to overtiredness, he emphasised that lated deficiencies of Air Traffic Control management are the man who is overtired is the last to know it. No matter more uniform internationally than in fact they are. The how stress was defined, if a man was not fully attentive paper succeeded in emphasising that from the controller's mistakes could arise, and more sophisticated equipment point of view stress presents serious practical problems could impose more strain on those who had to operate it. which are not yet being satisfactorily resolved.

Dr. V. Maxwell presented a paper on behalf of the U.K. Dr. C. E. Melton of the Aviation Physiological Labora~~ 1 Guild. He noted that about a third of the 150 people at the of the Aeromedical Research Institute at Oklahoma .

1 Symposium were doctors concerned with controllers, and described his research programme to derive biochemiffc~ air tra 10 that over half of those present were civil or military con• t·on and physiological estimates of stress amon g . the pub11ca 1 trollers. There was no agreement at the 1973 Symposium controllers in the United States. Fo 11 owm 9 . b f the on what "stress" was, and the U.K. Guild, through its jourof the Corson Committee Report in 1.971, ~~e t~oe ~nited nal "Transmit", had issued a questionnaire asking controlcontroller has now been legally defin~d is complex and lers to indicate sources of irritation and tension which could States as stressful. Whatever stress is, it d therefore effect efficiency and to assess whether lives or aircraft had not measurable by any simple measure, a~t rely on a ~ver been put at any risk because of stress effects. Pracattempts to devise a single stress indexd ~u or added to tical recommendations to ameliorate the problem were rebattery of measures which can be .amen ed and as the ~u~s~ed. It was concluded that although the U.K. Civil . d as further useful measures are d1scove~e relative importance of existing measures .•s ~evrse . viation Authority set high standards for working conditions compared indices of stress these were not always met. Similar conditions should apply Dr Melton's research has . . deriv~d from a variety of biochemical and phys1olog1c~I t~ non-state controllers. Deficiencies in physical and en·ndi"ces of sources of stress related to Air vironmental workspace were mentioned as sources of measures w1"th 1 .

Traffic Control, particularly traffic density: The latter has str~ss, Including reflections, sitting positions alongside taken into consideration both commercial and general horizontal displays, close proximity of controllers' work 41

Wish the controllers would believe that all this Is to their very best â&#x20AC;˘â&#x20AC;˘â&#x20AC;˘

aviation aircraft movements, and expressed these as traffic movement rates. Certain towers handling general aviation almost exclusively rank near the top in terms of aircraft movements in the United States. The present state of the research is that firm relationships between stress measures and air traffic movements have been established.

These rely on biochemical and physiological changes which can be measured without interfering with the controller's task performance and which can be interpreted objectively and impartially. The findings are sufficiently encouraging to be followed up, both by further research and by communicating them to those in operational positions. The method also enables data on anxiety proneness and anxiety states to be gathered and used to interpret other findings. Dr. Melton's paper provided much encouraging factual evidence of progress towards establishing a definitive measure of stress.

Dr. J. W. H. Kalsbeek of the Ergonomic Laboratory in Amsterdam outlined the formation and history of the "Stress in Air Traffic Control Research Association" (SATCRA), and then presented a paper on behalf of SATCRA. Units of physical workload have been derived, and there is now a quest for comparable units of mental workload. A tired man can assimilate much less information than an alert one. If the man has too little workload he tries to get more, and if he has too much he tries to get less. His preferred workload level represents his optimum level of activation, which thus follows a 'U' shaped curve.

Decision-making loads mental work; the number of conscious decisions which can be reached in a given time is limited, and decreases as the period of continuous decision making increases and as age increases. Fatigue introduces transient blocks in decision making which can impair the speed or quality of a decision if they coincide with the need to make one. Mental workload is a function of the number of conscious decisions per minute, the number of factors which can influence the decision, and the number of options which can be remembered and selected. Air Traffic Control systems therefore have to be planned to take account of work as related to workload.

Dr. Kalsbeek added some deliberately contentious remarks, speculating on why controllers as a group have a reputation for being difficult to manage - an apparently universal complaint, independent of the actual quality of management. If people interpret their environment or working conditions as menacing this can lead to certain symptoms of paranoia. If paranoia is a response by controllers to overloading, certain management problems could be 42

attributable to it. One cure is to enlarge the scope of jobs and to rotate controllers' and administrative jobs. As intended these remarks provoked lively discussion.

Mr. V. D. Hopkin of the Royal Air Force Institute of Aviation Medicine at Farnborough distinguished between performance, workload and stress. Each of these concepts has two distinct meanings. Performance may refer either to the system or to the man. System performance is measured by relating inputs to outputs, and the findings are expressed in system terms, such as traffic handling capacity or smoothness of flow. The performance of the man is described in terms of his actions and decisions. Measures such as speed, accuracy and consistency of task performance are used, and individual differences are included.

Workload may refer either to the demands placed on the man by his tasks or to the effort he expends in meeting those demands. In the former sense, the general demands of the task are derived from the system requirements and are relatively consistent, but in the latter sense workload is variable since it depends on the skill, experience, knowledge and training of each individual. Different people may therefore have to expend different effort to achieve the same level of performance.

Stress is used to refer to both stimulus (cause) and response (effect), the latter being also referred to as strain or distress. Stress as a stimulus may be physical (noise, cold, etc), load or speed stress (too much to do, or too little time to do it), task stress (responsibilities, safety standards, etc), employment stress (management quality, shifts, morale, etc), social stress (relationships with colleagues, etc), or stress not directly related to work (financial or domestic crises, etc). Stress as a response is an attribute of the Individual, and varies according to circumstances and personality. Behavioural, subjective, physiological and biographical evidence may all be relevant. Attempts to alleviate stress may incidentally affect workload and performance.

Professor W. Rohmert of the University of Technology, Darmstadt, presented a paper on determination of stress and strain of air traffic controllers in which he described controllers' tasks, the techniques of field studies conducted at Frankfurt and the current results of his research. He was concerned with the relationships between task demands of the work situation, the qualifications for controllers and the capacity of controllers. Currently Air Traffic Control is largely manual at a low state of technical development, with most functions performed by the controller and co-

â&#x20AC;˘ ¡ ¡ and to improve their working conditions

ordination, which is a product of internal organisation, occupying much of his time. Stress as a stimulus was mediated by individual capacities, resulting in strain which could be related to an individual's strain endurance limit.

Strain could be considered in relation to occupational medicine and health disturbances, to applied psychology and job satisfaction, and to physiology and the intensity and flow of strain. Other controllers could judge the difficulty of the control tasks and give a commentary on it and this could be supplemented by work study methods. The findings could be related to multi-channel telemetric transmission of measures of strain in the man.

Heart beat rates, measuring strain, were related to mental load expressed in terms of number of aircraft controlled and difficulty of traffic patterns. Tremble amplitude was also related to task difficulty. Data from 115 controllers at Frankfurt have been used to provide a model of the relationship between strain and the number of aircraft being controlled, taking into account the cumulative time of the controller's work. The model is used to predict the workload of Air Traffic Control tasks and percentage increases in strain are associated with the number of aircraft controlled and with time on watch. The intention of this research is to describe the time flow of strain measures as determined by known stress factors. This would enable the effects of different causes of strain to be distinguished so that steps could be taken to reduce specific identified sources of strain such as continuous watch lengths.

Dr. M. Carruthers of the Department of Chemical Pathology at St. Mary's Hospital Medical School in London presented a paper on risk factor control. His thesis was that by taking a forward look at stress problems and anticipating them, many of them could be forestalled. Stress is a common factor impairing both health and performance and among controllers it could be reduced by selecting controllers less susceptible to it, by changes in training or by changes in working conditions. In career patterns the abrupt change of function towards management needed closer study as does the distribution of hours of duty, particularly continuous watch lengths. Physiological changes associated with shift systems could be assessed by a portable apparatus giving 24 hour physiological measures.

There was also a need to avoid the almost pathological fear of doctors and their tests which could in itself cause great stress. In general, tests efficiently revealed early warning signs and enabled a preventive medicine approach to be adopted successfully in Air Traffic Control. Heart attacks do not come without warning but have many early signs and symptoms which are usually more obvious to others. There may be increasing fatigue leading to a reduction of non work activities, increased body fluid retention and blood pressure, or increased anger or aggressiveness perhaps with some symptoms of paranoia. The relevance of diet and smoking was also established. Social and domestic stresses could swamp work stresses in given individuals. It was emphasised that these however were trends and there was no absolute cut-off in physiological measured levels in the sense that there was no level below which it was certain not to get an attack or above which it was certain that there would be an attack. Vigorous but not violent dynamic exercise was beneficial. The use of beta blockers did not prevent the release of hormones but did prevent their consequences. There existed the possibility that a selection procedure to remove those most prone to stress might also inadvertently remove some of the best controllers and therefore caution was needed.

Dr. A. Wagstaff, a senior medical adviser with the Civil Aviation Authority in London and currently Senior Medical Assessor of Air Traffic Control Officer Licences in the United Kingdom, described some of the relationships between personality and the incidents of various psychosomatic illnesses. He noted that while United Kingdom controllers did not apparently succumb to these illnesses more than comparable working groups, clinical observation was not sufficient to establish this and it was hoped in future to provide statistical information on the subject. He identified several factors affecting well-being at work and perhaps leading to anxiety and Illness. These included underwork, promotion, financial insecurity, lack of communication and concentration and vagueness about job definition in terms of the part the individual played in the system and to whom he was responsible. There are more factors working for job satisfaction than against it. Favouring job satisfaction in Air Traffic Control were challenge, discretion

43

and responsibility, the opportunity to use skills and abilities, social contacts at work, contributions to the end product, variety and scope for learning and progression. Against job satisfaction would be a lack of necessary skills for the job, insufficient freedom to make decisions, the demands of paced work, the impersonal nature of the ATC organisation and the repetitiveness or lack of variety in the job.

The middle aged controller had the dilemma of choosing between making a continued effort to meet the standards of the job or giving up. Cardiovascular disease and neuropsychiatric illness were the two main causes of ending of an air traffic controller's career in middle age. To alleviate these problems certain practical steps in preventive medicine could be taken. These include the introduction of personality and aptitude testing, the moulding of career development to take better account of the ageing process, the detection of incipient disorders early enough to permit

continuation of careers and more encouragement of controllers by their own organisations to keep fit and lead healthy lives.

Following the papers many points were raised both formally and informally in discussions. The complexity of the concept of stress clearly emerged and research to establish its causes must itself therefore be complex.

Nevertheless progress has been made and findings can be quoted which are of value in two ways; firstly they provide management with evidence on practical steps, in selection, training, task design, job satisfaction, and career development, which could be taken to alleviate some of the problems of stress; and secondly they provide the individual controller with evidence of the practical steps which he can take, such as keeping fit, stopping smoking and seeking early medical advice, to alleviate the problems of stress in himself.

News From Corporation Members AEG-Telefunken AEG-Telefunken is evaluating a mobile 3-D air surveillance radar designed to provide high detection capability at medium ranges. Designated the TAMS, it is stated to combine wide coverage volume with good height resolution and a high data rate. Electronic beam scanning is used for search in elevation, while the phased array antenna (designed by Hughes Aircraft Co.) is rotated mechanically in azimuth. To optimise system cycle time, elevation beam-width angular velocity and pulse repetition frequency vary as a function of slant range.

One of its main performance features is cited as unsusceptibility to intentional and natural interference: the resolution cell is minimised by narrow beaming and pulse compression, while frequency and phase de-correlation are used to reduce sea clutter. Processed plot information is presented both in analog form on a plan position indicator tube and as a multicoloured synthetic digital display.

The complete equipment is transported in two trucks and can be set up in 30 minutes.

Ferranti Limited An order worth ÂŁ 139,000 has been placed by the Danish Department of Civil Aviation with Ferranti Digital Systems Division to extend the capability of the digital Air Traffic Control simulator which the Division installed at Kastrup (Copenhagen) Airport in 1972. The number of displays is to be increased from 4 to 6 and the number of aircraft control positions from 5 to 7. In addition, the number of aircraft it will be possible to simulate will be increased from 30 to 42.

A new programme written for the simulator's FM 16008 computer will enable any of the controllers (blip drivers) to see in the bottom right-hand corner of his display a graphical fepresentation showing the position of his aircraft relative to the nearest navigational reference point (i. e. beacon, holding point, or ILS localiser). The track 44

history of the aircraft will also be shown. This pictorial display will enable the controller to assess a situation more easily and respond to enquiries from the student controller with greater precision. Although these extra facilities and units increase the workload imposed on the computer it can c~pe without the need to increase its data processing capacity.

Ferranti has also secured a contract worth ÂŁ 78,000 to add the si~~lation of secondary surveillance radar (SSR) t~ tha fac1ht1es of London Airport's Ferranti digital ATC simulator. The simulator is used to train controllers in Approach Control procedures relevant to London Airport.

As SSR aircraft identity and height information has been added to primary radar presentations (range and bearing) on the operational displays, it was considered essential to provide comparable information on the simulator to create the necessary high degree of realism in training. A 260,000word magnetic-drum has been added to the system to hold exercise data and programs, and the central computer store is to be extended by 8,000 words.

In anot~er. ~evelopment, the operational capability of the Ferranti d1g1tal ATC simulator supplied in 1970 to the Netherlands Department of Civil Aviation has been extended for the second time. The simulator is now to be used to generate aircraft radar data for use in validating the operation of the new automated ATC system (SARP) at Schiphol (Amsterdam) Airport. In addition to its use for system evaluation and trials, the simulator will be employed in its conventional role to train existing ATC staff in the operation of SARP before the new automated procedures are introduced in 1978. Two peripheral control units have been provided to link the Ferranti simulator to the SARP system.

In the first extension made to the Schiphol ATC simulator last year, additional aircraft control positions and information storage capacity were added. The total contract value of the two-phase extension carried out by Ferranti amounts to more than ÂŁ 70,000.

Glen A. Gilbert & Associates Gilbert's study "The United States Air Traffic Services Corporation" (Volume No. 1 dated May 1, 1975, and Volume No. 2 dated October 1, 1975), reviewed in the November 1975 issue of "The Controller", has received wide attention.

On September 30, 1975, Congressman Barry Goldwater Jr. introduced a Bill (H. R. 9930) in the U.S. Congress titled the "Independent Federal Aviation Agency Act of 1975".

This Bill basically would create an independent Federal Aviation Agency as per the Federal Aviation Act of 1958, in turn removing the existing FAA from the Department of Transportation. Based on the general format of the study, on February 26, 1976, Congressman Teno Roncalio introduced a Bill (H. R. 12165) in Congress titled "The United States Air Traffic Services Corporation Act of 1976", which goes one step further and calls for the creation of an independent government corporation to take over the functions of the present FM, reporting directly to Congress. It is anticipated that a companion Bill will be introduced in the Senate in the relatively near future.

Congressman Glenn M. Anderson, Chairman, Subcommittee on Aviation of the House Committee on Public Works and Transportation, said in a speech at the Washington Aero Club on February 24: " . . . In the Fall, we hope to examine the relationship between the Department of Transportation and the Federal Aviation Administration in order to determine if this structure is in the best interests of the American people, and if we are compromising safety and aviation merely to solve some theoretical puzzle in which bureaucratic graphs and charts become paramount to actual performance."

Congressman Anderson reiterated this statement in remarks on March 9 at the Annual Convention of the National Air Transportation Associations (NATA). Both H. R. 9930 and H. R. 12165 will no doubt be considered during the course of the hearings alluded to by Congressman Ander-

4 HAMIL TON PLACE LONDON, W1V 080, UNITED KINGDOM.

CONVEX '76 London 28th - 29th October 1976

The United Kingdom Guild of Air Traffic Control Officers has over the past few years, organised a biennial conference ·on ~ current aviation topic.

This .Ye~r. on th·e· 28th - 29th October, the London Lodge of the Gull~ 1s orgamsmg the conference which is to be held at the Ce~tre Airport Hotel, near Heathrow Airport, London. The theme which has been selected for this year is "Noise Abatement _ Saf~ty or Silence" and papers from invited speakers for the sym· pos1un:i .have. already ~een promised from Lufthansa, Air France and .British Airways. It 1s hoped to have papers presented by various bodies to re~resent all point~ of view with respect to the problem and. each series of presentations will be followed by a discussion period where the presenters will form an open-forum panel.

The Centre Airport Hotel is providing all the facilities for this Conference and is convenient for the city centre ( 12 miles) the motorway (M4) a~d. Heathrow Airport. The hotel has agre~d to offer rooms at the a1rl.me rate applicable at the time of the function (at present a 5?% discount) and bookings for these will be done through the Guild.

I~ ~h.e foyer. outside the Conference Hall, E~h1b1t1on. For th~se not requiring stands in

there will be a static the Exhibition there will be an opportunity to advertise in the Conference brochure. bWe hope d · that we will have the pleasure of meet"rng you ·m o et· o e~ an . 1t would help us greatly if you would return the attached Regrstratron Form as soon as possible.

son.

International Aeradio Limited International Aeradio Limited has been awarded a £ 1.2 million contract to supply the new Sharjah International Airport, Trucial States, with ILS, DVOR/DME, communications equipment, Air Traffic Control consoles, crash tenders and appliances, and ground-handling equipment. The airport construction programme was due for completion in May 1976. IAL has provided technical services at Sharjah since 1948.

International Air Carrier Association The Association has commended Spain for the support it has given charter air transport over the years which has materially aided the development of tourism to that country and has permitted millions of people to enjoy lowcost holidays within Spain. IACA has also congratulated Spain on its recent adoption of policies which recognise the country of origin rule concept, as well as competitive pricing based upon the efficiency of each air carrier.

IACA re-affirms on behalf of its membership the continued goal of making low-cost air travel available worldwide through charters, which is the most efficient air transport system, and enables the public to travel long distances at minimum cost. Without the liberal aviation policies of

CENTRE AIRPORT HOTEL, HEATHROW AIRPORT. LONDON 28 291h OCTOBER 1976

REGISTRATION FORM

Please comple1e uson9 BLOCK LETTERS and rclurn 10 Ro9,.1ta11on Secreiorv. CONVEX 76. 3 WE LBYCRESCENT. WINNERSH. WOKINGHAM. BERKS U.K RG1 I SSW F1nt Name

Nam• Maohny Address

Ple.nc re~1s1er me and find enclosed the fee for tt1ck wherf! apprcpr1ate)

c::::J c:::J c::::J c::::J

1

S1andard Regostra11on

2

EJ(h1b11ors Rcg11trat1on

3

Addotoonal E.hobotors Regomatoon

1£25001 1£15.001

D•leljalCS Partner 1(1 50 I GATCO Reg,.1ra11on 1£300 I 6 IF ATCA Regostratoon 1(5 00 I All r~g1strahons (except Ocle9..un J)artner .ind GA TCO s.tt belowl 111cludt' -

c:::::J c:::J

4 5

Tea Cocktaol Portv

Thursda-..· o m

Morning Coffee

Friday .am

Bullet Lunch

Frida\' Noon

Tea

Friday pm

anU copies ol .ill Papers presented dt Symposium Delegates P.artner inch.u.Je-s .ill above, except Prnented P.ipers. but includes LadrC'S Proqr.Jmmt" In ar1di1eon to above I re(1mrc e•1r..l tickets for ~1nd1cate numbeni

C::=J C:J

Bulle1 Lunch

CJ

Donnor O•nceT.6el' 1(6001

1£2 501

GA TCO Mem~rs

IC I 751

Coc~t••' P•rly f£:Z 501

ACCOMMODATION

Bookonq do«-ct. on form prov•d•••l 10 ""'REGISTRATION SECRETARY

£6 SO per EXHIBITION SPACE Absoluh• tk.uJltnc for eonfumed in wrumca

SomC'

spJct~ 11111 av.i11Jhlr.

r~fund on

COST ,\PPROX

ncrson per night

.ul;.

or .tll of

for !urttwr dt•tad\ t•Clr..

.ithl'll't' ft"1t"n, 1t1oris 1\

li~I!'

D

15!b Octot"M.:r 1976 ,.\1 • .1ncrllal•on'I. MUST h._.

All cht•qut·~ m.ic.tl- 01..11 ro '"CONV(X lti

THI CONVI X 16 Cl)l,11,HTTH I OUK FORl'IARO TO ~E i ,,;G YOU ,\T THl ,~;~.Tilt :.il1PDH l HOT 1 •

45

Spain over the past 15 years, charter air transport might well have been stifled. Forces throughout Europe are still at work to try and curtail charter air transport on the North Atlantic, especially through the European Civil Aviation Conference (ECAC), whose members appear more interested in protecting high cost scheduled air services than adopting policies which would facilitate the· further development of charters. But Spain, notwithstanding restrictive ECAC proposals, has now spoken out as the champion and advocate of liberal aviation policies. Spain was the first European country to state categorically that it will accept traffic from all countries in accordance with the rule of the generating country and that it will not adopt any minimum pricing criteria which would artificially peg prices based upon the inefficient operators' costs.

This policy of permitting carriers to establish their own price based upon the efficiency of that carriers' operation, permits the free market to work and allows competition to ensure that the consuming public obtain service at the lowest reasonable cost. This policy is based on complete reciprocity between countries. It was hoped that other European countries would follow Spain's example rather than follow the restrictive policies being proposed within ECAC by some European countries such as the U.K. and Norway. These two countries would appear more disposed to protect inefficient scheduled air transport instead of protecting the consumers' interest. IACA has also emphasised the need for reciprocity between countries for landing and uplift rights, particularly between Europe and North America.

The Association cannot see why, within Europe, many countries such as Scandinavia, follow highly restrictive practices Which_ preclude the inflow of tourists as well as the ability to generate traffic to many destinations. This is but one example of problems confronting charters throughout the world, and governments must foster and adopt policies which would further the development of tourism and expand the traffic based. This would benefit not just charter air transport, but the air transport industry as a whole.

Marconi Radar Systems Limited . The company will supply Luton and Guernsey airports with S3004 Distance From Threshold Indicators (DFTls). }he S3004, of which about 120 have now been sold, accepts inputs from normal radars and is designed to offer Tower c?nt~ollers a bright short-range radar display for daylight viewing of .a.ircraft tracks approaching the runway.

Marconi is also supplying the ICAO Category 3 version 0 ~ ~heir. IVR Mk 2 runway visual range system to Britain's C~vil Aviation Authority for installation at Belfast Aldergrovo Airport.

Phi!ips Telecommunications An order has been secured for the supply and installation of equipment at the airport of Salalah in the Sultanate of Oman. Under the 12 million guilder transaction finalised to date the essentials will be installed, such as equipment for AFTN and VHF/HF ground-to-air communication, a category 11 I LS. two dual consoles, a VOR/DME beacon and a recorder. Under a follow-up plan not yet finalised the ground-to-air capability will be expanded by the addition of UHF equipment, two more dual consoles will be installed

46

and a variety of navigation aids will be provided such as radar and VHF/UHF-OF. The firm order is planned to be completed before the end of 1976. After commissioning, the equipment will be maintained for 2 years under the supervision of Philips engineers. Staff training will be done in situ as well as in the Hilversum International Training Centre. AFTN traffic will be catered for by HF communications equipment to be installed both at Salalah and at the Seeb internationar airport near the capital Muscat. The link between the two stations will carry telegraph channels for ATC, meteo messages and, in addition, a direct telephone link will be installed between the air traffic controllers of the two airports. For ground-to-air communication Salalah will be fitted out with long-haul HF equipment as well as with VHF facilities for Terminal Area Control, Approach Control and the Control Tower.

An order has been placed with Philips by DHMI, Turkey's Civil Aviation Authority, for two complete Category II instrument landing systems for Ankara and lzmir airports.

These orders form a sequel to two earlier orders for identical equipment, one given in 1972 for delivery of a first system in Ankara, which has now been operational for quite some time, and one given in 1975 covering an ILS in Antalya.

Plessey Company Limited Plessey Radar has been awarded a contract worth more than £ 2 million by the British Civil Aviation Authority to supply a Processed Radar Display System (PROS). It will operate in conjunction with the IBM 90200 central computer complex at West Drayton to process information from primary and secondary radars.

A Type AR 15/2 medium-range primary radar and a fully automated Series 200 secondary radar incorporating codecallsign conversion for use at Acapulco Airport, Mexico, will be supplied. Similar equipment at another Mexican airport, Monterrey, entered service in late 1975.

Plessey Navaids has secured additional contracts worth some £ 1 million from the Cairo Airport Authority to provide further equipment and management services, on a turnkey basis, for the new control tower. And an order has been awarded by the Mexican Secretaria de Communicaciones y Transportes for the supply of a Plessey PLAN 50 Doppler VOR. It will be sited at San Mateo on the approach to Mexico City.

Selenia-lndustrie Elettroniche Associate S.p.A. As reported in the February 1976 issue of THE CONTROLLER, the Soviet Union, after a long evaluation period, has chosen the new adaptive Selenia radars for its new Air Traffic Control System. The contract calls for 1O dual channel L-band radars, 5 of these "en route" radars, and 5 TMA radars to be delivered under the main system contract.

Selenia believes that the radars, which were selected after intense international competition with other radar manufacturers, are the most advanced ATC radars available today. The radars use the new "adaptive" technique, i. e. the radar probes the surroundings (ground clutter, weather conditions, angels, etc.) and reacts to the continually changing environment in such a way that the radar returns

from aircraft are presented with a high probability of detec1ion, while at the same time the false alarms are kept rigorously low.

Solartron Electronic Group Limited Solartron-Schlumberger have been awarded a contract for an Air Traffic Control simulator system worth over £ 750,000 by the Republic of Singapore. Won in the face of fierce international competition, the system covers the full spectrum of Air Traffic Services. Training on the system will cover the full range of air traffic requirements from automated flight plan processing through Area Control radar to liaison with Aerodrome Control, adjacent centres and ancillary services. Complete flexibility of exercise preparation will permit facilities to be used in almost any combination including the simultaneous running of two independent exercises.

The principal feature of the 120 target simulator is the use of eight Solartron .. Interactive Keyboards and Terminals" (IKAT's) enabling 'pilot' operators to interrogate the central computer - a PDP 11/35 - and input instructions to control any aircraft taken from their pre-programmed flight paths by the student controllers. It has been proved that by using this method of track control, simulator pilots can become proficient in a matter of hours, rather than weeks. Another important feature of IKAT is that special software makes it possible to provide a rapid and sensitive enough response for use with precision approach radar. Hitherto, this has been accomplished satisfactorily only with analogue control systems. (A full description of the IKAT system was given in the November 1975 issue of "The Controller").

The display system will comprise six 23" Solartron plan position indicators presenting both raw and plot extracted primary radar video together with digitised secondary surveillance radar complete with code-callsign conversion. The radar parameters are selectable during exercise preparation within a wide range of characteristics. The simulator does not therefore limit the Singapore Government's choice of the area radar system which has yet to be ordered by them. All software and hardware apart from a few equipment items have been progressively developed on previous Solartron projects.

Thomson-CSF Thomson-CSF and Telemecanique are planning to establish a joint company to manufacture mini-computers in France. In a preparatory move, Telemecanique and Cll are negotiating to set up a joint venture in the minicomputer field. The French government took action in 1975 to re-group and strengthen the French computer industry _ action which led to the effective disintegration of the European Unidata multi-national electronics group.

A controller went for his compulsory hearing test at the Acoustic Laboratories on Christmas Eve. Staff were not terribly keen to do it, but he was finally taken to a booth to take the test by a slightly merry lab. assistant. After taking the test the assistant said, "This is very serious, Sir; according to this test, you are deaf."

The assistant had forgotten to turn the machine on.

(Cocodoodledoo, Sydney)

Publications Review Planning And Design Of Airports - Second Edition.

Robert Horonjeff. McGraw-Hill Book Co., New York, 1975.

460 pp. Illustrated. £ 14.70.

About 30 seconds flying time separates Hounslow Heath whence Britain's first commercial passenger aircraft took off for Le Bourget in 1919 - from London's Heathrow International Airport.

How many people present on that occasion 56 years ago, could have foreseen the changes which were to take place - resulting in vast and complex organisations such as that which has grown up some two miles away.

Robert Horonjeff's book, first published in 1962, deals fully with all facets of these developments. But such has been the continued growth of air transport, and the evolution of more sophisticated types of aircraft, that he has felt the need to revise and update the work.

For those not already familiar with It, suffice to say that I could find no subject related to the bringing Into being of an airport and its subsequent orderly development - which was not dealt with authoritatively and concisely.

The work naturally draws largely on experience and "knowhow" developed in the United States. To this extent Chapters One and Two are perhaps of academic interest, though the history they trace will be of value to students of aviation and the Governments of newly-emergent countries. The chapters dealing with aircraft characteristics, Air Traffic Control, capacity and delay, overall airport planning, heliports and STOLports, while deriving mainly from United States practice, yet follow closely the guidelines of ICAO - as developed by all member states. The Standards and Recommendations of Annexe 14 - the !CAO "Bible" on aerodromes are well embodied In Chapters Six, Seven, Eight and Ten. Reference Is also made to the important work of Calvert on approach lighting.

Those who are already familiar with the first edition, will find that legislatlon, technical data, and statistics have been updated, and there is new Information on airport noise, passenger facilities, and STOLports.

A most valuable book for those engaged in airport planning - or seeking knowledge on any aspect of an airport.

(Gp Capt G.F.K. Donaldson in .. AEROSPACE")

Supersonic .•. Basil Jackson. Norton $ 6.95 Not having read Mr. Jackson's other books, '1 "fQJUld this one following a mode not unlike the style set by Arthur Haley in "Airport". Even the title is reminiscent. It is a book of fiction but with an element of fact undoubtedly based on the author's own experience in the aircraft Industry together with an acknowledged amount of advice and information provided by a number of aviation and Air Traffic Control sources.

A story of a supersonic transport flight planned from London to New York, with all the ingredients of a Mach 3 thriller, it did not quite strike the right note for me, concentrating perhaps too much on "hazards" of this new era of travel. These, we are told on the jacket, reflect the author's vision that they are "compelling, terrifying and all too probable .•. " But such emotive words say little for the aircraft Industry and at least one reader could dispute that vision.

We are also told the book is written with scientific authority. Some of it would appear to have been so, mostly within the author's own past disciplines. There is a commendable description of fuel-flow mechanics affecting altitude, trim and the cruise-climb mode of the book's fictitious SST which one could not entirely disassociate from the way It all happens with Concorde! Perhaps there is too much play on the subject of galactic radiation which doubtless could be ascribed to journalistic licence.

In assessing the degree of ATC interest in this book - and a fair portion is devoted to ATC aspects of the story - there is, alas. much to criticise. Unqualified adventures by authors into any technical environment doubtless require a relatively quick harvest of knowledge. There are, in this book, rather more howlers than one would expect in view of the obvious expert assistance the author clearly received from ATC authorities on the western side of the Atlantic. Having said that, one is left with the thought that he could not have sought advice regarding his references to the U.K. and Shanwick OAC ATC scene which, I would assure him, is rather different than the picture he paints in the book. A major criticism of the book must, for an ATC readership, be directed to the fact that R/T

47

dialogue and phraseology generally Involving air traffic controllers is incorrect and in some cases quite unintelligible - but perhaps we should not be too sensitive to a work of fiction in that context.

There are a number of operational aspects of SST operation which one might question, particularly in relation to the point of transition into supersonic climb. Another frightful howler in the book is contained in an "explanation" of the difference between Flight Levels and Altitude given by the book's SST captain to an eminent passenger. The captain had it all wrong, I fear, and one suspects that Mr. Jackson also did not really grasp his altlmetry briefing either!

Finally, it seems doubtful whether the author's understanding of undoubted excellent advice given by Gander ATC staff did justice to that advice. Perhaps Gander - based readers will feel rather embarrassed by the Gander part of the story, particularly in respect, again, of the RfT phraseology used by the book's PAR controllers.

Some of this was, to the reviewer's ears, mostly incomprehensible gibberish ... and as for that splendid instruction given to the SST, "turn right ONE degree ••. !!" It Is highly unlikely that Gander Centre would ever wish upon themselves a PAR whlzz-kid, reserved even for emergency recall by the Chief when on a day off, of the type portrayed in the book. He would not last two minutes in ATC units I know. Neither would the Chief ••• I regret having appeared to crucify this book and so we come to the question whether or not you should acquire a copy to read.

Well, yes, perhaps you should ..• it is still a brave attempt, albeit not entirely successful, to embrace Air Traffic Control within air travel fiction. If readers remember that much, and that It is fiction after all, they may not wince quite so noticeably.

(LSV in "Transmit")

A controller from Los Angeles has been named PATCO representative on FAA's new Air Traffic Procedures Advisory Committee. He will participate in the study on terms and procedures in the Air Traffic Control handbook to standardise and clarify it for all users.

The Committee was created by the Secretary of Transportation, after he had established a task force to examine the overall organisational structure and management approach of the FAA, including its use of delegations in carrying out its legislative safety mission, and to examine the relationship of the safety mission to the FAA's other missions. The task force recommended the creation of a standing group composed of air carrier, controller, general aviation, military and pilot representatives, to review Air Traffic Control procedures and practices.

Advisory committee meetings are open to the public.

IFATCA Information Handbook The Federation has publlshed the second edition of its Information Handbook. The Handbook now contains Information from 29 Member-Countries about: Conditions for entry into the Air Traffic Control Service Work environment in Air Traffic Control Conditions of service in Air Traffic Control Remuneration of Air Traffic Controllers Recent developments in Air Traffic Control Systems Social security In Air Traffic Control Methods of determining conditions of operation and service The Information as contained In the new edition has been gathered since 1973 through a yearly updated questionnaire distributed by IFATCA's Standing Committee IV, which the Committee cl rculates to all Member Associations of the Federation.

In order to keep this source of information continuously updated, IFATCA has instituted an amendment-service. The information received In the future will be analysed and should determine part of the future work-programme of the various Standing Committees of the Federation. lnltlally, Standing Committee IV have produced 200 copies of the latest edition of the Information Handbook. All Member Associations are entitled to one copy each free of charge. Further copies can be ordered for a price of Sir. 50,(Members of IFATCA Sir. 25,-) and readers may order directly, by means of an international money-order, to: Account No. 72'892-9, Swiss Credit Bank, BALEXERT, CH-1211 Geneva 28, Switzerland.

(PATCO Newsletter)

To receive your own personally addressed copy of THE CONTROLLER regularly complete this form today.

To THE CONTROLLER Subscription Service Verlag W. Kramer & Co. D-6 Frankfurt/Main 60 Bornheimer Landwehr 57a Please send me THE CONTROLLER for one year by surface mall/ airmail (please Indicate). Rates are OM 6.- for members of IFATCA, DM 10.- for nonmembers. Postage will be charged extra according to the tariff in use. Subscriptions not cancelled three months prior to termination of a calendar year, will automatically be extended for another year.

Name

..........................................................................................................

Complete Mailing Address ....................................................................................... .

. . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .. .. .. . . . . .. . . . . .. .. .. . . . . .. .. . . . . . . .. . . . . . . . . .. .. .. .. . . .. .. .

Signature

48

........................................................................................................

Corporation Members of the International Federation of Air Traffic Controllers' Associations AEG-Telefunken, Frankfurt a. M., Germany Airport Lighting Engineering Consultants, Birkerod, Denmark ASSMANN GMBH, Bad Homburg v. d. H., Germany CAE Electronics Ltd., Montreal, Quebec, Canada Cossor Radar and Electronics Ltd., Harlow, England Compagnie lnternationale Pour l'lnformatique, Le Chesnay, France Dansk lmpulsfysik A. S., Holte, Denmark Ferranti Limited, Bracknell, Berks., England Glen A. Gilbert & Associates, Washington D. C., U.S.A. Ground Aid Group, Esbjerg, Denmark Gustav A. Ring A/S, Oslo, Norway International Aeradio Ltd., Southall, England International Air Carrier Association, Geneva, Switzerland Jeppesen & Co. GmbH., Frankfurt, Germany Lockheed Electronics Company, Inc., Plainfield, N. J., U.S.A. The Marconi Radar Systems Ltd., Chelmsford, England The Mitre Corporation, Mclean, Virginia, USA N. V. Hollandse Signaalapparaten, Hengelo, Netherlands The Plessey Company Limited, Weybridge, Surrey, England Racal-Thermionic Limited, Southampton, England Selenia - lndustrie Elettroniche Associate S. p. A. Rome, Italy Societe Artistique Fran~aise, Paris, France Societe d'Applications Generales d'Electricite et de Mecanique, Paris, France Societe d'Etudes & d'Entreprises Electriques, lssy Les Moulineaux, France Sofreavia, Paris, France Software Sciences Ltd., Farnborough, Hampshire, England The Solartron Electronic Group Limited, Farnborough, Hants., England Stansaab Elektronik AB, Jarfalla, Sweden Telerad S. A., Anglet, France Thomson - CSF, Paris, France Ulmer Aeronautique, Clichy, France The International Federation of Air Traffic Controllers' Associations would like to invite all corporations, organizations, and institutions Interested in and concerned with the maintenance and promotion of safety In air traffic to jo!!'l their organization as Corporation Members.

Corporation Members support the aims of the Federation by supplying the Federation with technical information and by means of an annual subscription. The Federation's international journal "The Controller" is offered as a platform for the discussion of technical and procedural developments in the field of air traffic control.

STAIVSAAB - the Swedish data systems company, specializing in modern Air Traffic Control, where high demands are placed not only on systems but equally on controller performance. A modern ATC simulator for controller training is therefore an important part of any advanced ATC programme and consequently a logical product for Stansaab.

The ad vanced System Simu lat or for ATS - SATS - inst~lled in Sweden's A ir T ra ffic Ser vices Academy at Stu r up, Malmo.

Stansaab's simulator projects: SWEDEN - the Board of Civi l Aviation System si mul ator for Air Traffic Services (SATS). Most on-the-job training is replaced by rea listica ll y simu lating the controller env iron ment. Modular system design also perm its rap id reconfiguration for investigating future operational system requirements.

- simulator for Swedish Air Force (TAST) provides training fac i Iities for radar trackers, observers, height operators and intercept controllers.

EUROCONTROL - display system for the Ex perimental Data Processor (EDP) at the Eurocontrol Ex perimental Centre, Bretigny, France.

FEDER A L REPUBLIC OF GERMANY - simulator for training Approach Controllers and Precision Approach Controllers for the German Air Force.

SOVIET UNION - air traffic contro l system simulato r for Aeroflot, sim ilar to SATS, but with additional facilit ies.

Stansaab Elektronik AB • Veddestavagen 13 • S-175 62 Jarfalla • Sweden