BR's SECOND GENERATION DIESELS 

FEATURING PROTOTYPES: DP2 - LION - FALCON - KESTREL 

After five years into the 1955 Modernisation Plan, the British Transport Commission (BTC) abandoned its original concept of diesel locomotive requirement, and began seeking a new single-engined Type 4 of more than 2,500hp, which could be mounted on a Co-Co wheel arrangement. This followed criticism of the poor power/weight ratio of the earlier 1Co-Co1 Type 4s ordered under the modernisation scheme. The English Electric Co’s candidate for the new Type 4 was DP2 - Diesel Prototype 2 - which emerged from the EE Co Vulcan Foundry in May 1962. It was essentially an enlarged version of the EE Co Type 3 Co-Co (later Class 37) the extra power being provided by the company’s charged-cooled version of the 16-cylinder 16SVT engine uprated to 2,750hp.  

The EE Co’s DP2 appeared in Deltic-style bodywork, as savings on production costs could be made by using existing materials. In 1962, the prototype began trials on the LMR based at Camden shed and passed its first year on a diagram covering a remarkable 3,600 miles per week. However, in view of the LMR’s impending electrification between Euston, Liverpool and Manchester, DP2 was transferred to the ECML and during the summer of 1963, was regularly covering 5,270 miles per week between Kings Cross and Edinburgh, taking the 10.10 each weekday from Kings Cross and returning overnight on the 22.30 from Edinburgh. As it turned out, DP2 was the most intensely utilized of the prototype Type 4s, which led to an order for fifty locomotives, Class 50, the first EE Co design to eliminate the characteristic nose ends on the company’s Class 55, 37 and Class 40 fleet.

 

 

 

 

 

 

 

 

 

 

 

 

(Above) The privately-sponsored EE Co prototype DP2 was employed on the ECML to cover for the withdrawal of the Deltic fleet one by one for train heating boiler modifications. Despite the rigorous Type 5 schedules, DP2 had a similar trouble-free spell of service as it had done on the WCML. The prototype appeared in a production 'Deltic' bodyshell with modified louvers and is seen departing from Kings Cross with the 9.50 for Newcastle on September 23rd 1963. Photo © GE-Alstom 

 

 

 

 

 

 

 

 

 

 

(Above) Prior to receiving the full Deltic livery, the raking light picks out the dumpy proportions of DP2's Deltic-style bodyshell (in overall dark green) as the prototype speeds through Finsbury Park with the 'up' 'Yorkshire Pullman' in September 1963. An updated version of DP2 formed the basis for the D400 class (later Class 50) with flat-fronted cabs as ordered by the BRB. (Below) Yet to turn a wheel in revenue-earning service, No D403 awaits acceptance trials at the EE Co works at Newton-in Willows. 

 

 

 

 

 

 

 

 

 

 

Another private venture - 'Lion' - was built by a consortium of AEI, BRCW and Sulzer Brothers. The BRCW was responsible for its design and construction, AEI supplied the electrical equipment, and Sulzer the 12-cylinder engine, producing a 2,750 hp Co-Co prototype - well within the BTC’s specification for a 2,5000hp Type 4. At the same time, BR asked the industrial designers, Wilkes and Ashmore, to produce specifications for the future Type 4, and 'Lion' closely followed the designers recommendations, albeit in a startling all-over white livery. The locomotive entered regular traffic on May 14th 1962, and although BR was greatly attracted to the design, BRCW’s financial problems left grave doubts about the company’s ability to supply the 2nd-generation Type 4.  

(Below) Unlike DP2, the ‘Lion’ prototype closely followed the BR design panel's specifications for the new Type 4, using industrial designers Wilkes and Ashmore, consultants for the earlier Brush D5500s, BRCW D5300s Type 2s, and diesel-hydraulic 'Hymek' classes. The BRCW Co’s 2,750hp ‘Lion’ can be seen departing from Leeds Central station with the 'up' 'Yorkshire Pullman'. Photo © GE-Alstom      

 

 

 

 

 

 

 

 

 

 

 

 

 

Meanwhile, Brush Traction set about the task of developing a prototype Type 4 locomotive, wholly financed and owned by the company, but as there was no single diesel power unit available to produce the required 2,800hp, the company installed two high-speed Bristol-Siddeley/Maybach engines of 1,440hp. Aptly named 'Falcon' (after its builders works) the prototype began trials in BR service working from Finsbury Park depot.

 

 

 

 

 

 

 

 

 

 

 

 

(Above) The late summer of 1962 saw the end of two chapters in the development of BR main line diesel power. The first was the completion of the EE Co Type 4 D200s with the delivery of D399 - the last of 200 locomotives in the series - and the Type 4 Peak class was concluded at Derby and Crewe with Nos D193 and D57 being the last of respective batches built there. Also in 1962, 'Falcon' was used regularly on the 'Master Cutler' between Kings Cross and Sheffield, consisting of two round trips a day - 670 miles every 24 hours - albeit the lightweight Pullman of 240 to 320 tons made so little serious demand on a diesel locomotive of such power.  

Continuing the Brush Traction’s theme of birds of prey, another new prototype - 'Kestrel' - was conceived in 1965, by which time BR envisaged the need for a new 4,000hp locomotive. An agreement was made with BR to produce a high-powered prototype as a private venture to operate on BR tracks. A single engine had been developed to 4,000hp - the Sulzer 16LVA-24 - and the new electronics used in ’Kestrel’ came from the experimental 'Hawk' Bo-Bo (the Brush rebuild of the LMS/ North Br itish Co’s No 10800, as mentioned in ‘Pioneer Diesel’ Page 8). Indeed, from the Hawk experiment emerged the successful ac main generator to replace the heavy dc generators previously used in rail traction. However, all was not well with the new 4,000hp prototype, since the locomotive weighed 133 tons, some 10 tons heavier than the criteria laid down by the BRB. It was formerly handed over for trials in January 1968, but due to its higher than required axle loading of 20 tons, the prototype was restricted to tests below full speed and power, spending most of its time on freight duties in the Shirebrook area. Following the replacement of new bogies, an improved 21 tons per axle load was eventually achieved and Kestrel was finally accepted for 100mph passenger operation on the ECML.     

 

 

 

 

 

 

 

 

 

 

 

 

(Above) As it turned out, 'Kestrel' was not the beginning of a new era on BR, whose latest traction policy was heading towards the introduction of diesel multiple units for high speed trains (HST) and in 1975 the Brush machine was sold to the USSR. Nontheless, many valuable lessons had been learned both by Brush Traction and BR, for the 'Kestrel' prototype was the springboard of many new advances in applied technology for rail traction and the ac generator became widely accepted as standard. On October 20th 1969, the Brush/Sulzer 3,946hp 'Kestrel' hauled its first revenue-earning passenger service out of Kings Cross. Sporting streamlined cabs and a pleasing two-tone livery of brown and golden yellow, the driver applies power at the head of the 07.55 Kings Cross-Newcastle. 

Meanwhile, Brush Traction was awarded the contract for the new BR Type 4, and the first of the 2,750hp Sulzer-engined machines No D1500, emerged from the Loughborough works early in September 1962 for acceptance trials, but as the company did not have the capacity to construct sufficient numbers of the new Type 4 fleet, an agreement was made for some machines to be constructed under licence at BR’s Crewe workshop. The Brush machines weighed 114 tons, mounted on a Co-Co wheelbase which gave the fleet a much better route availability and enabled them to negotiate tight curves at dead-slow speed - a matter of some considerable importance in sidings and marshalling yards.

(Below) The first 2,750hp BR standard Type 4, No D1500, emerged from the Loughborough Works early in September 1962. This is a general view of the shopfloor and shows several machines in various stages of construction. The neat body lines of the Brush machine was enhanced by grouping all grilles in the roof section at cantrail level, whilst the front ends were a considerable improvement upon the original pilot scheme design, resembling the earlier Brush Falcon prototype.

 

 

 

 

 

 

 

 

 

 

 

 

(Below) As the Brush Works at Loughbrough was unable to build sufficient numbers of the new Type 4 to meet delivery targets, an agreement was made with BR for Crewe workshops to construct some of the locomotives under licence. A familiar sight on the WCML during the 1960s was the 1Z10 test train, when conditional paths were made available between Crewe and Carlisle for testing new diesels built either at Crewe or the English Electric Co works at Newton-le-Willows. With less than a year to go before the cessation of steam, Crewe-built Brush Type 4 No D1815 heads the return 1T94 test train south through Carnforth on the return leg to Crewe.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Please note...some photos have been re-sized to fit the page. If the text is illegible - simply click on photo (as you would a thumbnail) to see the original (readable) size.

 

 

To be continued....