Kartveli Article in Engineering and Research Article

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ENGINEERING AND RESEARCH ALEXANDER KARTVETI Vice President

Today, aeronautical science and its industrial application is progressing with such impetus that accomplishments which only a few years ago appeared almost impossible have now become common place. So, we arrive at

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it is due to necessity imposed by the troubled situation of the world, or the general tendency of the human mind to progress and lift the curtain of the unknown, the result is an unusual activity throughout the world to push forward man's idea of flight. Europe is recovering from the effects of war and is producing outstanding designs. Irom behind the iron curtgjg .o*"i a.-L;Ft ri u s uii a cti vi ty a n d-a ; ;r"rpf f, f , ;; ;,r: "o$s our own competitori in ttriieJunilft;e;&iii[" tremendous progress in various phases of the art.

Republic has a proud record of leadership in aeronautical accomplishments and in the advancement of the art. \tr7'e must use all of our experience, imagination and science to maintain this leadership. _Airplane design is like a lgaing match: Every_ so'often ttril chiinpio[ fifi to deferid his ,t!" *1g}y1 i-+1"9 m;if b" a"i""qea ar all.-eosts.

So that you may havii-e'cle-di pict.rre of whaiihis entails, I shall discuss a few major problems with which we are faced, what we are doing about them and what we must have in order to arrive at a satisfactory solution.

Modern military airplanes now reach high supersonic speeds, fly in high regions of the stratosphere and maintain their flight for several hours. Yet, under these conditions, they must have good flying characreristics, and must be able to withstand very high mechanical and thermal stresses. They must be able to navigate under all weather conditions of visibility and ceiling. They must be able to detect, locate and intercept the

enemy. They must be maneuverable and stable enough to engage the enemy or escape from sudden attack. They must be able to penetrate the enemy air defense system without being detected,

and have more than a reasonable chance of returning unharmed. The nuclear weapon must be delivered with precision at a distanie safe from the effects of explosion and radiation, Finalfy, they must be easily and economically serviceable and maintainable, and have adequate ground equipment to be ready to undertake the mission on short notice.

An airplane to fulfill all these conditions musr be equipped with an intricate combination of complicated mechanical, hydraulic, electronic and electro-mechanical machinery arraoged in a systematic and clever way compatible with available room and weight. Such an airplane is no longer iust an airframe, bur a complicated mechaniim called a weapon system. This concept of weapon system dominates all our activities today. \V'e now produce a weapon system of which many parts are sub-contracted but we have the final responsibility for its proper functioning.

As aircraft weapon systems become more complicated and expensive, the Air Force with its budget limited to a reasonable percentage of the gross national income, will be unable to afford more than one weapon system in each cutegoty.

T_usr*er-ir+*ance-"t-hg_Air ForE*yjll-beJorced..hy* economics to have only one sffa!9_g!g__h93b.g

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_l14-TEiE_1iffis the numUe"-oi ior,tracts and competition becomes great. Because of the fierceness of the competition, to interest the Air Force each weapon system must be well thought out.

The chosen v/eapoo system must be rapidly engineered and produced to preserve its advantages -for aircraft oerformance is onlv relative a,nd must be measured with respect to some calendar year. It must be produced in operational numbers, on time, at a compedrive price. Finally, this weapon sysrem must be reliable and maintainable.

High performance together with low cost is essential. Neither will sufrce without the other. S/e thus see that we are facing two simultaneous problems: Very rapid advancement in the art of airplane design and ever growing competition.

These problems are basic and are the key to our survival and success.r$/hat do we need to cope with these proble research and be well wl to marn-

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aerodvnamics.

Republic already has under conrract a small supersonic tunnel going to Mach No. 4 for testing inlets and structural flutter. \tr7e are organizing the construction of a much larger supersonic runnel for complete model tests of lift, drag and stability in the still higher range of speed. F.o;*fgs*e.ds. -o.q$Seoely-hfu ,h^rqggi1ude,w3-ggeggqt-emptating the construction of a soiilled shock tube &-EbTe of of

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4 f Sf + p g lplri g, litplli, "', " sifdi-.will.-fly. Republic airplanes were always excellent aerodynamically and we intend to give our engineers every necessary tool to maintain our aerodynamic excellence in future designs. rU7'hile the

aerodynamic problem is a cornerstone of aircraft design, there is a new and novel domain of problems which arises with the advent of high supersonic and hypersonic speeds. This is the problem of srructural material and the integrity of

the structure as a whole. As we all know, high speed generates a tremendous.amount of heat due to the friction of air against the body and surfaces :-*.!+4.!*rF]#.+;-,,',

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design, the advent of supersonic speeds inroduces many new unknowns in the domain of aerodynamics, flutter, structural adequacy and equipment.

\Zhile the classical problems of good airplane design are always with us, and we have a tremendous backlog'of accumulated experience to use as a check in our advanced research, these unknowns must be explored and solutions pfoven in research laboratories before we can proceed with any confidence into this unexplored region.

From the point of view of aerodynamics, very high speed poses new problems of lift, drag, stability and control which must be verified not only theoretically, but by very careful wind tunnel experimentation. Our aerodynamic tests are cur-. rendy run in Government facilities. This becomes increasingly diffcult due to the very large number of tests and studies involved, and heavy schedules of Governmental research work. It will, therefore, be necessary for us to acquire our own aerodynamic testing facilities. I can aszure you that very gositive steps are being pu-ntd'*66flon Tn the iiiy

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of the airplane. On the other hand, the tremendous power generated by the power plant produces an

enormous amount of heat inside the body. The structrre of the airplane must, therefore, be made of a material capable of keeping adequate strength in the presence of this heat. Commonly used aluminum alloy begins to lose its strength at approximately between 25o" and 3o0o F. which corresponds to about Mach No. 2. For speeds beyond this value, new materials must be used such as titanium and all kinds of high resisrant variedes of stainless steel. Unless these materials and their use are explored and thoroughly tested it will not be possible to design a successful airplane.

This is, in my opinion, one of"the basic problems we are facing to which a considerable amount of engineering efiort and research should be devoted.

As we progress still further into hypersonic speed, some of the exotic materials suitable for high temperatures, or some ceramic coating will be required. Several of these materials are undergoing preliminary investigations but a tremendous amount of data is still necessary.

The materials mentioned above are basic srructural materials. There are many prqblems of non---_a-."H

stfuctural materials that

will be used in aircraft

device must also possess strength at high tempera-

tures and freedom from optical distortion. The hydraulic fluids and seals must not decompose at high temperatures. From this you can gather that very high speed flying, other things being equal, depends upon the successful development of materials. This is one of the most important limiting factors. \7e shall need to acquire facilities to perform this iob. '!7e have already acquired a certain amount of equipment for this resarch work, but a much larger quantity is needed for a full knowledge of the problem. We "*.are*g-ggffi the ranse of rnaterials s-ffiq:-ry4q.P-l'-s** iimiffistudies of the applicat-ffi of thesgpaterials -*

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it i s an enormous undertaking to coyer thri whole spectrum of materials iovolved, we will organize our activities so as to be in constant touch with universities, Private and governmental laboratories and various industrial concerns in order to have the most advanced and up-to-date file on the subject available for design use.

Under the weapon system concePt we have the responsibility for the research and development necessary to design and produce adequate navigation, detection, fire control and guidance. To navigate with precision under all weather conditions over unknown and unfriendly land, to detect the enemy and position your machine in space with the accuracy necessary to desuoy another aircraf.t, or place a bomb on an airfield or river bridge is a tremendous problem. This problem today is much more difficult than it was in ril7'orld Var II due to great speeds and very powerful enemy air defense systems.

It might help to understand the complexity of the problem if I give you an elementary idea of how this is done. The aircraft, somewhat alone at high altitude in darkness and bad weather, is directed to the combat area either by ground radar control or by its own inertial system. tU7hen the combat area is reached, the target is locked on the

airborne radar installed in the airplane. The radar information is continuously interpreted by the computer, and through the action of the pilor or autopilot the aircraft is maneuvered into a correct position for firing the armament. The launching of armament may be automatic or manual by the pilot. This involves the use of complicated systems of electronic and electro-mechanical devices which transform an airplane into an intricate ar,ray of complex machinery, The magnitude of the problem will be better understood if I mention that in some weapon systems under development the cost of this equipment to the Air Force is almost one-half the cost of the complete system.

At present, most of this equipment is engineered and constructed by outside vendors. It is, however, our intention to become more closely associated with the design and production of at least some of these systems. This will give us not only a better control over the final product and the weapon system as a whole, but will give mote outlets and

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oudined some of our research problems connected with the rapid advancement of airplane design, and have given you a general idea of the steps which we are taking to meet these problems.

Let me now discuss the second problem-what we are doing to meetthe ever-growing competition.

As you all well know, the Company has developed a new type of fighter-bomber, the F-105, which is now undergoing flight tests at Edwards

Air Force Base.

This is an airplane with high potential and great versatility. $7e are now engaged in completing the production design of this machine and working out its applications for various tactical missions involving different equipment and different pilot arrangements. This will make complete use of the versatility of this weapon. At the same rime, we are looking into further improving the speed and altitude performance by studying the use of more advanced engines. .I honestly believejbat in the F-105 we have one of the moslup-to-date will be an wiiapon svstefrE-ilhich imporrant facror f,.% -. l-,_'

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in the defense of our Country. A

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production of fighter-bombers, we are concentrating our efforts in studying the fghter-bomber of the fu This and"sglving problems

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and altitude, we are very actively engaged in the problems of .air defense and interc"ptrs.

As you know, we are now engineering and con-

structing three prototype interceptors of the F-103 types. This project was staried some five years ago. \7e are v€ry energetically exploring the production possibilities oi this airplane and its adaptability to the most recenr coibat environmenrs. I believe that the XF-103 is the most advanced interceptor type under consffuction at present,

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ties in-[-wo different directi still rnore speed, of more range, more its naii tio iiii 6T-ni;Eath 6e

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aa;ig; "iS"affi?eabrEffii"eI "ideas in aerodynamics, structures, power plant and equipment, using the most advanced informations. Our studies have shown that the resulting airplane will be larger and heavier, consequentl, more expensive than the F-1O5. It will have its fighter capabilities de-emphasized in favor of bomber performance. It will result in a type of machine approachin g a tactical bomber in size and requirement. Further pursuit of this type wiil auromatically put us into rhe next logical field, that of tactical bomber, and will offer us new horizons of activities. \J7e are very seriously looking in this new direction.

Another approach to rhe problem of the furure fighter-bomber consists in studying a much smaller and lighter machine in the same class of speed, with somewhat smaller range and capabie of extremely short, and in some cases, vettical takeoff and landing. Such a weapon wilt be much less expensive, more economical to run and will permit dispersion of our Air Forces, thus rendering it much less vulnerable to enemy attack o., th" ground. This type has been under study for many months and we believe that we have found a very clever and practical solution. It is very probabll that one of our next experimental fighter-bombers will be of this type.

Pursuing our efforts in the region of high speed 40

limiting our activities in the inter-

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missiles and

intercontinental ballisric missiles. One of rhe conceivable methods of defense against such a threat may be a man carrying intercq>tor. To conceive such an interceptor requirei an entirely different design approach in regard to aerodynamics, structures and power plant. It also rLquires careful study of tactical considerations and combat methods and techniques to arrive at the performance required to accomplish this micsion 'S7'e are actively engaged in these studies. In particular, we are considering the use of more powerful engines based on principles orher than jet engines.

In regard to the problem of interception,-there are two opposite schools of thought, the man carrying interceptor versus the guided missile. In favor of the man carrying airplane, *jSAp"_o_-V"., fact that even the most clevedy conceffit -"ifr""i:

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bquipmen_q g]4pg1e_n;r _canitfr-G6iiE6llF-f"m;-ffi cao_ueJ ISFIIAES-AIman'- eye,

qgg!"49--lld_&l_9-9!.qndhumanrefl exCi-Iliffi ev-ar, [9s!ee__l.Ld_g.l]_-e_gt TrsI4s-,1 in refilCll-Ffimev-ar, guided missiles have progressed'to a'point where their practical use is more and more aisured every day. tU[e are, therefore, making equal efforts in

both lines.

Problems of an advanced interceptor and a guided missile have many points in ctmmon. As time goes by, both types of flying machines will rapidly converge to the same limit For instance, our F-1O3 airplane functions almost automarically.

The role of the pilot is reduced to the take-off and landing operarion, and supplying human i"dgment and rellexes to complement the automatic equipment in navigation and combat. For both

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ioterceptors and guided missiles, questions of nore intensively. Atomic power plants for afucttft aerodynamics, power plant, armament, electronics, are being developed by various leading engine systems and air frame are very similar and based companiesl atomic weapons are carried by most on the same principles and data. of our fighter afucraft; our fighters and bombers lW'e are thus converging to a new general aeqowill be exposed to the effects of radiation and niutical science of th-e fft.rre. Rep,r6lic is in the shocks due to atomic explosion; various sysrems ptocess of building the foundation for this underand mechanisms of our planes and missiles must taking in as far as personnel, laboratories, equip. be adapted to handle atomic substances. Atomic ment and general philosophy are concerned. This energy and its use will have more and more to say is our goal and we have every reason to succeed. in the design of the flying machines of the future.

Vhile designing and building military fighting It thus follows that it is imperative for us to be afucraft is, and for many years has been, the bulk closely associated with these activities. Spe intend of our business, we are looking for still other to do so and pursue it energetically. S[e are oudets for our activities. One of the promising gradually building a staff of atomic scientists by fields is commercial air transport. The advent of engaging them from the outside and educating jet and turbo-prop propulsion opened a new era our own people.IT'e intend to acquire laborator! and has given impetus to business in this domain. equipment and reactors generating atomic enefgy.

Of course the main bulk of the business, consisting S7e are developing various ideas for machines, of long range transoceanic and transcontinental using nuclear energy for propulsion. airplanes, has already been absorbed by other Jet propulsion took a long time for its developAircraft Companies in this country. ment but, today, it is in universal use for ahcraft There are, however, a few types of commercial propulsion. Following this pattern we must look titcraft which offer us a possible enry into this to the atomic power plant as the propulsion of field. We are thoroughly investigatiog these posthe future and be prepared to employ it to our sibilities. In particular, we are concentrating on advantage when the time is ripe. a small teo passenger iet transport which could be $7hen competition is keen and money and time used as a civilian executive or military petsonnel are scarce, the Company with the fathest vision tfanspoft. Ve have done a considerable amount will come out on top. This means that it will.be of layout and theoretical work on this and the necessary for us to draw a fine line between the results are very encouraging. The Company may possible and the impossible and proceed as close consider undertaking construction of a prototype to this line as our knowledge in the art will permit. of this aircraft. I7'e are also studyin g a jet replaceTo win the competition takes ingenuity, talent, ment for short range transport to replace now daring and gurs. An outstanding idea must be existing equipment below 10OO miles in range. conceived. To make this idea practical and achievThe Company is very eager to enter the commerable within the realm of science, engineering and cial field and we will continue to explore it. economics takes a crew of experienced scientific There is one more importanr domain in which men supplemented by a number of practical engiwe intend to engage-the field of nuclear energy. neers and research and testing facilities to try \7hile a few years ago this field was strictly conideas and make them workable.

6ned to the design and manufacture of atomic S7'e have established a foundation for this underarmament and related equipment, today it begins taking. Vhile it will take time and money to reach to influence the aeronautical industry rnore and the goal, I am confidenr thar our efforrs will pay off.

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