Diesel Dawn 7

DIESEL DAWN

7. WESTERN REGION 0-6-0s D9500-D9555 John Jennison Price: £12.99

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Exeter’s Railways

by David Mitchell A lavishly illustrated comprehensive survey of Exeter’s railway history.

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Diesel Dawn 6

by Gavin Glenister

No.6 in the Diesel Dawn series, describing the 263 locomotives built by the firm Brush Ltd of Loughborough from 1957.

Railwaymen of the Welsh Valleys Vol.2

by Philip W.L. Williams

The second volume chronicling the lives and times of railwaymen working in and around Pontypool Road loco shed.

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Lament for a Branch Line

2nd Edition by David Hindle The second edition of the evolution and complete history of the Preston to Southport branch.

More Memories of a Didcot Steam Apprentice

by Patrick Kelly Pat

Kelly’s day-to-day life at Didcot shed on BR’s Western Region in the dying days of steam, as a young inexperienced 15-year-old.

Stratford Depot Locomotives

by Roger Rounce

Includes Class 08s, 31s, 37s and 47s alongside less common classes such as 20, 58, 60, 86 and 87.

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Contents Déjà vu?

5

Technically Speaking

8

Livery and Styling

12

Allocations

13

On the Western Region

17

If you go down in the woods today…

31

To the Land of Green Ginger

47

After-life

49

Industrial use

53

After the After-life – Preservation

60

Histories

62

Acknowledgements

86

I

n August 1964, Modern Railways announced The first of the BR order for 56 centre-cab 650 h.p. diesel-hydraulic Type 1 0-6-0s has recently been completed by Swindon works. These locomotives, numbered in the D9500 series, have been designed and constructed to an essentially WR requirement under the overall direction of Mr. J. F. Harrison, BRB Chief Mechanical Engineer.

Specific features for their use on the Western Region have been incorporated and Mr. Innes, Mechanical Engineer (Design) at Swindon has been responsible for the detailed design. The Type 1s are designated main-line locomotives and are primarily intended for shunting duties and trip working with a maximum service speed of 40 m.p.h. The drive to the wheels is through jackshaft cranks and coupling rods. The use of a jackshaft was surprising because these had been superseded two decades years earlier by nose suspended traction motors in the standard diesel shunter design (originated by the LMS in 1945 onwards and continued by British Railways in what became the Class 08). Although it was a convenient way to take the drive to the wheels, it required a heavy mechanical construction and the use of coupling rods. To take the reaction of the drive the frame had to be stiffened and the wheelbase needed to be long enough to accommodate the jackshaft.

The crew of D9553 pose for the photographer at Dursley, probably in 1966. It followed the well-worn path from Dairycoates to Stewarts & Lloyds, arriving at their Corby Quarries in November 1968. It was in use until late 1980 but survived until February 1983 when it went for preservation to the Gloucestershire & Warwickshire Railway. Rail-Online

DIESEL DAWN

7. WESTERN REGION 0-6-0s D9500-D9555 (The ‘Teddy Bears’) John Jennison Cover. D9555 with a Coleford to Lydney Junction freight at Parkend on 31 March 1967. The picturesque scenery in the Forest of Dean attracted photographers to record the working of the class in that area. J.M. Tolson 7. Western Region 0-6-0s D9500-D9555

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Copyright Irwell Press Ltd & Mortons Publishing ISBN 978-1-911703-31-0 First published in the United Kingdom in 2023

by Irwell Press & Mortons Books, Irwell Press, 59A High Street, Clophill, Bedfordshire MK45 4BE Mortons Books, Media Centre, Morton Way, Horncastle LN9 6JR Printed by William Gibbons, UK www.irwellpress.com www.mortons.co.uk/publishing 3

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Diesel Dawn

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94XX 0-6-0PT 3409 at Radyr in the late 1950s was the last of the 210 Hawksworth 94xx panniers. It entered service in October 1956, less than six months before the Western Region decided that it would need up to 400 Type 1 diesels as part of its dieselisation scheme to eliminate steam traction. 3409 was withdrawn in October 1964, although it did manage a service life of more than double most of its D95XX successors! Rail-Online

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he 56 locomotives built at Swindon in 1964/5 had an average life in British Railways’ service of less than 3½ years and cost over £2 million (equivalent in today’s prices to around £30 million). They were disposed of, almost all into industrial use, at a considerable loss.

On first examination this appears to be a repetition of the 94XX pannier tank story, with Swindon having “form” when ordering large quantities of locomotives for which it had no use by the time they were built, in a tale which began less than a year after the last 94XX went into service.

However, the explanation for both debacles is very similar and becomes more understandable when the facts are examined.

In the case of the 94XX, Pannier Papers No.1 explained why they were built and what went wrong: In the economic conditions of the time (immediate post-war prior to nationalisation) it was right to plump for steam rather than a wholesale diesel programme; we didn’t have the shops, the expertise, the personnel or the money to build them here and we certainly didn’t have the dollars to buy them from the USA, the

Déjà vu? only realistic source. The Great Western Railway, for instance, had only one operational diesel shunter at nationalisation. In any event the 350hp diesel electric was no match for a pannier tank (traditionally also useful for passenger and goods, branches and so on, as well as shunting) at speeds above walking pace. For this sort of work a diesel locomotive of 750 to 1,000hp would be required as the speed reached the 35 to 50mph band and it would be necessary to provide steam heating for the train. In 1947 this was quite simply unimaginable.

At the end of the war in 1945 around a third of the Great Western’s 4,000-odd locomotives were 0-6-0 tanks, the majority of them the relatively modern 57XX class and its derivatives, dating from 1929 onwards. However, this left some 600 decidedly antique Armstrong, Dean and miscellaneous absorbed engines from the pre-grouping Welsh constituents.

Objectively, there was every scope for the replacement of these six hundred elderly locomotives; they were all in the shunting and medium mixed traffic categories which could be adequately covered by pannier tanks or the 2251 Collett goods tender engine.

With a slowdown on replacement during wartime the subsequent request from the

Running Superintendent for large quantities of new pannier tanks was thus perfectly explicable. If an error of judgement was made at all it was perhaps when the Great Western’s General Manager insisted that something ‘more modern’ than the 57XX should be built.

The 94XX was, in reality, a smaller wheeled version of the 2251 tender engine with tanks and bunker substituted for the tender. ln fact, the timing suggests that the ten Swindon built prototype examples utilised parts already in existence for a batch of 2251s. Most of the wearing parts and long lead items like cylinders, motion parts, connecting and coupling rods, boilers and so on were the same for the 2251 and the new 94XX locomotives. They could easily have been borrowed from the former, and later replaced by parts made for the latter, to produce the ten pannier tanks in the shortest time possible. It seems very likely that Hawksworth was simply being cautious in ordering a pilot batch of ten 94XX locomotives for evaluation, before embarking on a long production run.

When the 94XXs were authorised there was, despite perceptions today to the contrary, no universal appreciation that nationalisation would, in fact, come to pass.

The first intimation, other than anything

The ‘A’-end of D9509, the tenth locomotive on the production line, part-way through construction in Swindon Works famous ‘A’-Shop in mid-1964. The framework for the lightweight steel bonnets has been fixed and the radiator and engine are in place, and the cab has already been fabricated. Rail-Online 7. Western Region 0-6-0s D9500-D9555

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With the bonnets now complete and the cab fitted, D9500 was nearing completion in Swindon Works on 31 May 1964. It was ready for its press photographs four weeks later but did not officially enter service until 24 July.

contained in the Labour Party manifesto, of the nationalisation of transport came in the House of Commons in November 1946, well over a year after the election. Even then it was felt that a ‘considerable time’ would elapse before the plans could be implemented. The full text of the Transport Bill was made known on 28 November 1946 and Royal Assent came on 6 August 1947. By this time all ten locomotives of the pilot batch of 94XX panniers had been placed in service.

Nationalisation of the railways would follow soon afterwards, and it probably occurred to Swindon that if no orders were placed before the end of 1947, then it might be years before any more new locomotives became available. Therefore, the GWR elected for a very sensible action in the time available to it. ‘Sensing a period of organisational vacuum’ the opportunity was duly grasped and orders placed with the locomotive manufacturing “trade” for two hundred 94XX pannier tanks, and all the purchasing was completed before nationalisation. The Invitations to Tender were issued early in 1947 and the bids received back in June. Based on the Hunslet internal works copy order dated 7 February 1948 for the last of the 94XX build it is reasonable to say that all 200 locomotives 6

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were the subject of firm committed orders within five weeks of nationalisation. The new British Transport Commission’s involvement had been minimal - if that.

This was the key point; there was no turning back by any of the parties manufacturers or purchaser - without serious financial loss. The whole program had been structured to give what was by now the Western Region its two hundred 94XX pannier tanks within a time span of three years or so.

At that time the minimum delivery period which could be expected on any locomotive was 24 to 30 months from acceptance of order and then at a rate of two or three per month dependant on the size of the manufacturer and their other commitments. If this delivery programme had been achieved then all 200 would have been in service by the middle of 1952, long before any serious thoughts of widespread dieselisation were being entertained and before bus competition had begun to bite into local services in the Welsh Valleys and elsewhere. Doctor Beeching, Ernest Marples and motorways were a decade away. The railways were the massive common carriers they had always been.

Unfortunately, the plan soon began to fall apart, for a variety of interconnected

reasons. Most of the private builders had export orders which had been unfulfilled due to the intervention of the war; other orders, both home and export, were being placed at a rapid rate and there was a continuing workload of repairs. Steel was in short supply and production needed to be stepped up. The steel making processes of the day required coal, lots of it, and coal relied on the railways for its movement.

Coal was the first item in the supply chain and the Government looked upon this as a priority industry. The railway private manufacturers were over-committed, an inevitable consequence of five war years and the subsequent backlog of new construction.

On 15 November 1948 the Western Region wrote to the Locomotive Manufacturers Association advising that the Government had reduced the steel allocation to British Railways and, as a consequence, the rate of delivery of new locomotives was to be slowed. The LMA took up the matter with the Ministry of Supply who advised that this restriction applied to all BR locomotives whether built in BR’s own shops or by outside contractors. A year later the LMA was again advising its members of a further requirement from the customer to slow Diesel Dawn

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Area

Planned completion (2/57)

Covering

Type 1s included

1

West of England

1959

24

2

Bristol

1960

62

3

Gloucester and South Wales

1965

182

4/5

London, Birmingham and Chester

1968

100 368

deliveries. The note said that Mr Riddles of the Railway Executive was asking to be advised of the extent by which deliveries planned for 1950 could be reduced as the Railway Executive were being instructed to cut considerably their capital expenditure.

This was because of the national necessity to reduce capital expenditure and the suggestion was made that “as the association” (i.e. the LMA) “is engaged in vital export business Members may welcome some relief in the demands upon them from the Railway Executive”.

There is no doubt that (without these two requests for delayed delivery) most of the manufacturers would have been in a mess. From 1950 onwards the Western Region was completely in the hands of the manufacturers regarding delivery and the manufacturers were, in turn, tied into contractual obligations with other customers. Correspondence was polite and, whilst expressing disappointment, all Swindon could do was rely on the suppliers’ “best endeavours”.

The contracts signed by the GWR included a statement to the effect that all prices were based on costs ruling at the date of tender (i.e. June 1947) and were subject to adjustment on completion in the event of alterations to costs of materials, wages, hours, working conditions or any other changes. The right was reserved to make appropriate adjustments to the invoice at the time of delivery. Thus, the final invoice for the last engine delivered in October 1956 showed a cost variation (ie increase) of £4,204, almost 50% above the initial contract price of £8,720. This apparent profligacy with taxpayer money was solely down to the original contract terms and the late delivery and was not the fault of the 1950s Western Region management.

By the end of 1956, British Railways had already built around three hundred of the standard (later Class 08) diesel shunters and many of the 94XX went into store, with withdrawals commencing in 1959. They were perceived by many commentators as a waste of (taxpayer) money, but there was actually nothing that could be done once the GWR had initiated their purchase in 1947.

7. Western Region 0-6-0s D9500-D9555

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Now for the D95XX …

On 15 February 1957 the Western Region Area Board presented to the British Transport Commission Chairman’s Conference on Modernisation its dieselisation plan which included 368 locomotives of 800bhp out of a total requirement of 1,425 units; this plan was to be completed in four stages, by area, between 1959 and 1968 – see table, top. 86 of the lower-powered Type 1 locomotives were included in Stages 1 and 2, for completion in 1959 and 1960 respectively, but since no Type 1 design was then available Type 2s were temporarily substituted. This was less than six months after the last 94XX was delivered which implied that all of these engines would be withdrawn within the next decade or so.

However, this was only one example of the rush by British Railways to eliminate steam which would prove so costly.

Eleven Type 1s were put forward in May 1960 for the third area and after minor changes twelve 660bhp machines were authorised in February 1961 at a cost of £36,000 each (significantly below the 1960 estimate of £58,000); in addition, 44 Type 1s were carried forward from the first two area schemes, making a total of 56 locomotives. All would have hydraulic transmission, the debate on diesel-hydraulic versus diesel-electric transmission having not been completed by this date although it was already clear which would emerge as the victor. Their design followed the British Transport Commission Technical Committee recommendation dated 8 January 1960 which stated that future Type 1 locomotives should have a single, high cab and low bonnets to allow good visibility in both forward and reverse operation.

The Western Region justified its decision to opt for what was a relatively low-powered design on a number of points: -The locomotives would be needed mainly for trip freight and associated shunting work -The existing North British Type 2 was double-ended, and not suitable for shunting duties and was over-powered and too expensive for the work -The standard 350bhp shunter was not powerful enough and its maximum speed too low for main-line trip work

Revised 6/59

Revised 2/61

Revised 12/61

94

94

44

12

12

56

-The Type 1 900 bhp diesel-electric design (which emerged as the D8500 Clayton) was also more expensive at £50,000 each and therefore the 660bhp hydraulic, which was not equipped for train heating, would save around £15,000 per unit.

The Technical Committee Meeting on 23 September 1961 approved the proposal (which would save around £6 million if the number required was around the 400 units envisaged by the Western Region).

Final British Transport Commission approval did not come until January 1962 when it was agreed that tenders be requested to complete the first three WR Area schemes, including the now 56 660bhp Type 1s.

The following month, the Supply Committee Meeting recommended that the first 26 locomotives should be built at Swindon Works under Lot 456, filling the gap caused by the transfer of the production of ten Western Class 2,700bhp locomotives to Crewe Works, and tenders be invited for the remainder since at that date it was envisaged that no more locomotives were to be built at Swindon. The estimated cost was £34,520 each, of which the engines to be supplied by Davey Paxman & Co. Ltd would account for £7,550 and the transmissions from Voith in Germany another £6,400.

Contracts for the remaining thirty locomotives under Lot 500 were agreed in early 1963 for the transmissions at £5,584 each with Voith Engineering Ltd in the UK and with Paxman for the engines at £7,954 each. In an about turn, these were also to be built at Swindon at an estimated unit cost of £35,429, which was below the lowest trade price offer of £37,250 from Beyer, Peacock & Co. As with all railway inhouse “costs”, what went into the quoted figure was very much the product of an accountancy art form, and was not directly comparable with an actual purchase price from an external supplier.

However, as with the 94XX, the Type 1 story was then overtaken by events with the publication in March 1963 of the ‘Beeching Plan’ which at a stroke aborted the idea of any more Western Region Type 1s since trip working would be eliminated as quickly as possible because freight services would be rationalised and focussed on block train loads. Thus, both the 94XX 7

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D9500 posed for its official portraits on 25 June 1964. The diesel equivalent of the GWR pannier tank with its spoked wheels and coupling rods. The basic equipment layout of these locomotives involved a central driving cab, with the forward nose compartment housing the engine, cooling equipment and exhausters, whilst in the rear hood section were the transmission, auxiliary generator, and compressor. The 4 ft. 0 in. diameter wheels had cast steel centres with pressed-on tyres, and balance weights covering three of the twelve spokes. The non-fluted coupling rods were jointed at the flycrank and intermediate axle positions. Initially, there were shrouded double-clasp brake blocks at the ‘A’-end side of all six wheels.

and the D95XX were delivered in different circumstances than when they were first conceived and ordered. In the diesel’s case, however, the money wasted was much more visible than with the 94XX in the 1950s as the following section demonstrates. Firstly, there was the almost inevitable cost over-run – see upper table at right. The final reported “cost” of the locomotives came in at over 20% more than forecast at £42,357 each, amounting to an over-spend of around £412,000. (In today’s money, using the Bank of England’s inflation index for Goods and Services, this equates to around £5.6 million). The Swindon figures are in the lower table at right. The British Railways Board authorised

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Building costs Original authorised Actual

contribution to the fixed overheads of the Works which would have been incurred irrespective of the construction of the locomotives.

Total for 56 locomotives £1,960,390 £2,372,000

Each at 1964 prices £35,007 £42,357

Under-estimates before final design completed Modifications needed during construction Price inflation since original estimates made Design changes

Each at 2022 prices £560,000 £677,000

£ 240,000 32,000 116,000 24,000 £412,000

Technically Speaking

he leading particulars opposite suggest that the D95XX was, perhaps, Swindon’s diesel-hydraulic development of their beloved pannier tanks!

The underframe was conventional, with two heavy main plate frames 1¼ in. thick 8

the additional expenditure in February 1966. It was probably not quite as bad as appears at first sight since a significant proportion, probably 20-25%, of Swindon’s “cost” was represented by the

and 30 ft. 6 in. long, stayed with vertical and horizontal stretchers and carrying outriggers to support the full-width cab, side fuel tanks and battery boxes. The 15 ft.

6 in wheelbase, unevenly spaced at 6 ft. 6 in. and 9 ft. 0in. was the same in total as the 94XX panniers, although these were spaced

at 7 ft. 3 in and 8 ft. 3 in. Deep bufferbeams were provided, 5 in. thick at the ‘A’ end and 1½ in. thick at the ‘B’ end, which ensured an even distribution of weight on the coupled wheels. Independent laminated springs bore directly on to inside Timken roller bearing cast-steel axleboxes, Diesel Dawn

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Leading particulars Length over buffers Weight in working order Wheel diameter Wheelbase Max. tractive effort at 27.6 per cent adhesion/85%

D95XX 34ft 7in 50 tons 4ft 0in 15ft 6in 30,910 Ib.

Fuel capacity Axle loading Maximum service speed Maximum width overall Minimum curve negotiable

338 gallons 17 tons 40 m.p.h.

8ft 7-9/16in 4½ chains

which ran in manganese steel-faced, cast steel hornblocks.

The 4 ft. 0 in. diameter spoked wheels had cast steel centres with pressed-on tyres, and balance weights covering three of the twelve spokes on each wheel. The flycrank was fastened to the projecting ends of the jackshaft and had a 10 in. throw. The nonfluted steel coupling rods were jointed at the flycrank and intermediate axle positions.

One (longer) bonnet at the ‘A’-end housed the engine and cooler group and the other at the ‘B’- end the hydraulic transmission and brake equipment frame.

The fuel capacity was 338 gallons, carried in three tanks at the ‘A’-end, one on each side of the running plate in front of the cab and the third mounted between the frames

94XX 0-6-0PT 33ft 2in 55 tons 7 cwt.

4ft 7½in 15ft 6in 22,515 Ib.

19 tons 5 cwt.

8 ft. 7 in.

to evenly distribute the weight and avoid undue changes in the weight distribution during acceleration and braking or when working on steep gradients. Shorter boxes with hinged chequer plate lids, at each side of the footplate behind the cab at the ‘B’end, each housed two 24 cell CromptonParkinson batteries. The bonnets were of simple light gauge sheet steel construction, with the full width driving cab insulated thermally, and from engine noise. Access to the equipment was through hinged doors, four to each side at the ‘A’-end and three to each side at the ‘B’-end, and through sealed removable roof covers fitted with ventilators; hinged nose doors were also provided. At the ‘A’-end, fixed radiator louvres were positioned on either side, with a circular grille in the roof for the

air-intake fan. Twin train headcode boxes were provided at both ends, with one double digit box in the back of each nose access door.

The spacious sound- and draughtproofed cab tapered inwards from the lower edge of the sliding side windows to the end profiles of the high roof. There were two large windows in each bulkhead, contoured to follow the roof profile and the uppermost corners of the bonnets, and the cab doors were fitted with droplights.

Air operated windscreen wipers were fitted and there were two-tone Desilux air warning horns on top of the bonnets in front of the cab. At the ‘A’-end, these were fixed in front of the engine exhaust stack, that was itself attached centrally to the outside of the forward cab bulkhead.

There were duplicate driving positions, one for each direction of travel and the electrical control cubicle was positioned against the forward bulkhead, with the Driver’s desk, seat and Secondman’s positions against the rear bulkhead.

Power came from a Paxman Ventura 6YJX diesel engine fitted with a Napier exhaust gas-driven, water-cooled turboblower. This six-cylinder vee engine had a maximum continuous traction rating of 650 hp at 1,500 r.p.m. The engine was flexibly supported on four Metalastik mountings and the drive to the

D9544 next to D0280 FALCON in Swindon Works during May 1965, shortly before it went into service at the end of the month. The cab tapered inwards from the lower edge of the sliding side windows to the gutter line of the roof. The large windows which gave excellent visibility to the crew were contoured to follow the roof profile and the uppermost corners of the bonnets. Note the continuous upper handrails which ran along the top edges of the bonnets. Rail-Online 7. Western Region 0-6-0s D9500-D9555

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The official front end view of D9500 shows the shunter style black/yellow chevrons, yellow bufferbeams and buffer housings. However, since the Class would work on the main line, twin train headcode boxes were provided at the front and rear, with a two-digit box housed in each access door. There is only a brake pipe on the bufferbeam because there was no train heating or multiple working equipment. The flat metal strip handrails which ran along the top edges of the bonnets on D9500 as first built did not pass completely round the ends, but stopped short at the front, just around the outer corners. It was quickly modified and all the others were built with a continuous rail.

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transmission was through a Holset flexible coupling mounted on the flywheel and a Hardy Spicer cardan shaft that ran in a tunnel through the centre of the cab at floor level, separating the Driver’s and Secondman’s positions. Engine starting was similar to that in a car, by means of a CAV non-axial starter, which engaged with teeth on the engine flywheel.

The hydraulic transmission was a VoithNorth British Type L217u containing two torque converters in series with a fluid coupling. The first converter was used for starting and low speeds, the second for intermediate and the coupling for fast speeds; only one circuit was in use at a time,

the changeover from one to another taking place automatically when the speed reached the values to which the transmission governor was set.

A Hunslet triple reduction and reverse gearbox was bolted directly to the main frames so that the cast steel jackshaft bearing housing was midway between the intermediate and trailing wheel centres.

Reversing mechanism was incorporated in the second reduction stage, air-actuated by a double-acting pneumatic cylinder situated outside the box, although reversing could also be done manually. The radiator, cooling fan and motor, controller, hydrostatic tank and associated pipe-work were supplied by

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Above. A Paxman Ventura 6YJX diesel engine ready to be installed at Swindon Works in July 1964. The lightweight, six-cylinder vee engine had a maximum continuous traction rating of 650 hp at 1,500 r.p.m.

They were fitted with a Napier exhaust gas-driven, water-cooled turbo-blower. The engine was quite compact in size, 63¼ in. long by 55¾ in. wide and 56 7 8 in. high.

Serck Radiators Ltd. as a complete unit, and the SerckBehr system for control of the fan speed was employed.

A Plessey hydraulic pump was mounted directly on the engine and supplied oil under pressure through a controller with a thermostatic valve located in the engine cooling water system, to the fan motor. Variation in the cooling water temperature varied the oil pressure to the fan motor and hence the speed of the fan.

A Westinghouse vacuum-controlled air brake system was fitted with two motor-driven rotary exhausters to produce the vacuum for the train brakes. The driver’s vacuum brake valve applied the train brakes when vacuum-braked stock was being hauled and at the same time a proportional application of the locomotive airbrake was made. A driver’s air-brake valve allowed the locomotive brake only to be applied. A passenger/goods valve slowed down the proportional brake application Left. The spacious sound- and draught-proofed cab had duplicate driving positions, one for each direction of travel and the electrical control cubicle was positioned against the forward bulkhead, with the Driver’s desk, seat and Second man’s positions against the rear bulkhead.

7. Western Region 0-6-0s D9500-D9555

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when switched to the “goods” position. A driver’s safety device provided for the application of locomotive and train brakes if a foot switch at the driving position or a push-button in the end of the controller handle was released. Initially, there were shrouded double-clasp brake shoes at the ‘A’-end of all six wheels but, after extensive trials with D9517 following cases of tyre overheating and cracking, they were changed to unshrouded single blocks, probably from D9549 onwards; earlier locomotives

were soon modified under MB442/23. Air assisted sanding was provided, with the sandpipes feeding in front of the leading coupled wheels and behind the trailing wheels, the sand boxes being fitted to the outside of the frames.

Diesel shunter-style shunters’ steps, built up from steel plate, were provided at the front and rear with a third set of strap-type steps giving access to the cab. There was wire mesh behind the cab steps to prevent contact with the flycranks. The handrails

which ran along the top edges of the bonnets were not the traditional round bar, but flat metal strips; on the official photographs of D9500 these did not pass completely round the ends, but stopped short at the front, just around the outer corners. Howver, when it entered service, the rails had been changed to the continuous pattern which was fitted to the remainder of the class.

There was no provision for train heating or for multiple working.

D9500 fresh out of the shops shows how the two shades of green set-off by the yellow ends made the D95xx rather pretty little locomotives. There are shrouded double-clasp brake shoes on all six wheels but, after extensive trials with D9517 following cases of tyre overheating and cracking, they were changed to unshrouded single blocks probably from D9549 onwards; earlier locomotives were soon modified. Sanding was air assisted, with the sandpipes feeding in front of the leading coupled wheels and behind the trailing wheels; the sand boxes were fitted to the outside of the frames. J. Cramp/Colour Rail

D

Livery and Styling

esign Consultants Allen-Bowden Ltd were used to advise on detailing with George Williams, BR’s Director of Industrial Design, saying that there would be similar problems to those recently encountered with the Clayton Type 1 diesel-electric. Williams also put a cap on their work at £600 compared to the £610 they had quoted! Allen-Bowden’s first input was to suggest that “holes might be provided instead of the traditional steps” and that they would advise on the colour scheme. Next, they took exception to the amount of “louvring needed in the bonnet 12

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access doors” which they thought was “rather serious from the Industrial Design point of view” and then said that the air cowls on the top of the bonnets “look totally out of place”. Minor changes to the louvres were the only concession agreed by Swindon. In fact, the design was pretty much complete by the time Allen-Bowden came onto the scene and cost constraints were too tight for any significant changes.

Attention then turned to the livery and the consultants’ proposal to use a base livery of anything other than the standard locomotive green was swiftly vetoed by

George Williams, as was their suggestion to use Class 52 Western style cast numberplates. Allen-Bowden came back with the idea that the cab sides should be in a (lighter) Sherwood Green with the buffer beams in yellow, both of which were taken forward; they also thought the lower handrails should be white - this was initially rejected as impractical since they would become dirty after a few days in service but was subsequently implemented and all the handrails were white.

Thus, when D9500 emerged from Swindon, it was in an attractive two-tone Diesel Dawn

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