British Rail Class 52

An early photo of D1005 Western Venturer in 1962.

When switching to diesel traction as part of the Modernisation Plan of the 1950s, British Railways (BR) designed, and commissioned designs for, a large number of locomotive types. At this time BR's regions had a high degree of autonomy, which extended as far as classes of locomotives ordered and even the design criteria for those locomotives. Whilst almost all other diesel locomotives were diesel-electric, the Western Region employed a policy of using diesel-hydraulic traction, originally commissioning three classes of main line locomotives: a type 2 and two type 4s (later designations class 22, class 41 and class 42). With pressure to increase the speed of the transition from steam to diesel, volume orders for the class 22 and class 42 (along with a similar design class 43) followed in 1957, a mere two years after the original orders and well before any idea of performance or reliability could be gained. At the same time it was realised that all the existing orders (diesel-electric and diesel-hydraulic) were for types 1, 2 and 4; thus orders were placed for 101 Type 3 diesel-hydraulics (later Class 35). However the increasing demands for more powerful locomotives prompted a further order, in 1961, for 74 diesel-hydraulics of 2,700 hp (2,000 kW); so when the first locomotive was outshopped from Swindon Works in December 1961, less than a year after the order was placed, the Westerns were born.[2][3]

The theoretical advantage of diesel-hydraulic was simple: it resulted in a lighter locomotive than equivalent diesel-electric transmission. This provided a better power/weight ratio and decreased track wear. Unfortunately, it had several key disadvantages:

• The technology was proven in continental Europe, particularly Germany, but was new to the UK. At the time, it was considered politically unacceptable for the UK government to order railway rolling stock from foreign companies, especially German companies so soon after the Second World War. This resulted in most of the engines and transmissions being manufactured in the United Kingdom under licence from the German manufacturers.[4]
• The most robust hydraulic transmissions were only capable of handling engines with power output of around 1500 hp (1120 kW); to build a more powerful locomotive would involve two diesel engines and two transmissions.
• The transmission had significantly higher power losses than diesel-electric, negating some of the benefits and resulting in considerably higher fuel consumption.

Experience showed that the Bristol-Siddeley-Maybach engines were superior to those made by North British Locomotive Company-MAN and although the use of twin engines in the same locomotive was new, the design did not produce any insurmountable problems. In the end the diesel-hydraulic experiment foundered on low fleet numbers, poor maintenance conditions and design issues; not on its German heritage or development of a novel configuration. BR's Swindon Works maintained all the diesel-hydraulic locomotives, and their early demise resulted in a much reduced workload and hastened its eventual closure in 1986.

D1023 Western Fusilier at Exeter St Davids with a train for the South West

With the Hymeks and Warships already in service but proving underpowered for top-link services, BR Western Region needed a high-powered locomotive for these trains – the Western therefore needed two diesel engines to achieve the required power output. In keeping with their policy, a new locomotive with a hydraulic transmission was envisaged. Experience had shown that the Maybach engines in the Hymeks were superior to the earlier Maybach and MAN engines used in the Warships, particularly in power output. Also Maybach were able to offer their 12 MD engines rated at 1,350 bhp (1,010 kW) allied to a Voith transmission; a Mekydro transmission designed to handle such power could not be fitted into the British loading gauge.

Prototypes sited the engines behind the driving cabs but drivers found this too noisy; moving the engines centrally meant making the locomotive heavier, removing some of the design's advantage. In operational use, the dual-engine arrangement turned out to have some advantages: in particular, the Westerns were able to continue operating with a single engine running in situations where more conventional single-engine designs would require rescue by another locomotive.

The most serious continual problem with the class was the design fault mismatch between the Maybach MD655 engines and the Voith L630rV three speed hydraulic transmissions. The top gear ratio in the transmission was too high for the torque characteristics of the engine: the result was that a single locomotive could struggle to reach its claimed 90 mph (140 km/h) top speed in the absence of down grades, more so when work-weary and due for overhaul. These factors, combined with the South Devon Banks (a major part of their running grounds) deleterious effect on tired engines, all conspired against the Westerns continuing in top-line service. With fifty Class 50 locomotives becoming available, following completion of the West Coast Main Line electrification, and new High Speed Trains, the speed and comfort increases the Western Region sought could be achieved and the Westerns dispensed with. Towards the end of their careers the Westerns were all allocated to Laira (Plymouth).

Distribution of locomotives,
July 1967[5]

82A 84A
Code	Name	Quantity
82A	Bristol Bath Road	15
84A	Laira	59
Total:		74

Whilst the design was largely successful, the working life of the class was relatively short. Its non-standard design added to its maintenance costs while the national British Rail policy was moving away from diesel-hydraulics. When the Westerns were introduced in 1962, the Western Region had 226 diesel-hydraulics and 10 diesel-electrics (excluding shunters); by 1966 the numbers were 345 and 269 respectively. As a result, the early 1970s saw the decision taken to retire all the diesel-hydraulic types. Class 46 and Class 47 took over passenger and heavy freight while Class 25 covered the lighter duties. Following completion of the electrification of the West Coast Main Line throughout from London to Glasgow, the Class 50s were reallocated to the Western Region; the introduction of High Speed Trains three years later was the final nail in the coffin for the Class 52 Westerns.

In 1968–69 the Westerns received train air brake equipment in addition to their vacuum exhausters, thus significantly extending their working lives, unlike the similar but lower-powered, Warship class, although four of the class (D1017–D1020) did not receive dual brakes, with these locomotives being among the first withdrawals. The vacuum brake equipment was retained and to fit the additional equipment, it was necessary to remove one of the fuel tanks.[6] However, as with the Warships, it proved impossible to equip them with electric train heating (ETH, or head-end power in US terminology). The Western Region faced particularly stiff competition for its prime inter-city services in the mid to late 1970s from the M4 motorway and it was generally felt within BR that a significant speed and comfort increase on the prime London Paddington-Bristol route were necessary. The lack of ETH meant the Westerns could not power the newly introduced air-conditioned BR Mark 2d/e/f coaches – a shortcoming that classes 47 and 50, equipped with ETH (the latter from new), did not share.[7]

The highest recorded speed with a Western that O. S. Nock was aware of was 102 mph (164 km/h) when D1068 hauled nine coaches (305 tons gross) down 1 in 1320 (i.e. virtually level) at Southall. The train averaged exactly 100 mph (161 km/h) for 12.8 miles (20.6 km) between Slough and Ealing whilst hauling a service from Reading to Paddington.[8] An unverified eyewitness account by a BR secondman stated that 110 mph (177 km/h) had been achieved when his driver drove a Western between Reading and Westbury. He experienced the locomotive shaking from side to side as 110 mph was indicated on the speedometer.

However, when it came to drawbar horsepower the Westerns in some respects were less capable than the equivalent diesel electric locomotives. Nock states "whilst the Westerns took their rightful place as fast and powerful locomotives it became evident that they were showing the same deficiency in actual power put forth at the drawbar as the [diesel-hydraulic] Warships had done. The highest output that came to my notice was a sustained 85 mph (137 km/h) hauling 560 tons descending 1 in 1320, which equates to 1500 edhp (equivalent drawbar horsepower)".[9] This is 56% of power at the flywheel, whereas for a diesel-electric one would normally expect a figure of 75 to 80%. A similar result was obtained when Clough & Beckett[10] compared the performance of type 4 diesel locomotives (Classes 45/46/47/50/52) hauling trains up the ascent to Whiteball summit. They deliberately chose data to show each class in their best light and included a Western run which produced 1775 edhp but they still concluded that "without doubt the Westerns get the wooden spoon; certainly not what one would expect from units of 2700 bhp". The best performer was the Class 50, a 2,700 hp (2,000 kW) diesel-electric locomotive: on one run this achieved 2115 edhp.

Despite this apparent limitation, the BR Western Region load-limit book gave the same 550 ton loading figure for both the Class 52 and Class 47 diesels over the South Devon banks between Newton Abbot and Plymouth. The reason for this is that, while the diesel-electric classes could produce high maximum tractive effort for limited periods, diesel hydraulics could produce significantly higher continuous tractive effort.[4]

Name and numberplates at the National Railway Museum

While the first Western was under construction, proposals for livery and names were prepared by the BR design panel. The D1000 series locomotives were to be named after famous West of England place names; the illustration from the portfolio shows D1000 bearing the name Cheddar Gorge. This was not followed in production, however, and the Westerns were named with general heraldic and regimental terms prefixed with the word "Western" as per the following table.

Of the 74 locomotives built, 7 have survived to preservation.

Image	Number	Name	Built	Liveries	Withdrawn[11]	Disposition	Notes
	D1000	Western Enterprise	BR Swindon 20.12.61	Desert Sand Maroon Rail Blue	02/1974	Scrapped 31.07.74 BREL Swindon
	D1001	Western Pathfinder	BR Swindon 12.02.62	Maroon Rail Blue	10/1976	Scrapped 08.77 BREL Swindon	Originally outshopped without yellow warning panels; the buffer beams being painted yellow instead [12]
	D1002	Western Explorer	BR Swindon 19.03.62	Brunswick Green[13] Maroon Rail Blue	10/1976	Scrapped 08.77 BREL Swindon
	D1003	Western Pioneer	BR Swindon 14.04.62	Brunswick Green[13] Maroon Rail Blue	01/1975	Scrapped 08.77 BREL Swindon
	D1004	Western Crusader	BR Swindon 12.05.62	Brunswick Green[13] Maroon Rail Blue	08/1973	Scrapped 19.09.74 BREL Swindon
	D1005	Western Venturer	BR Swindon 18.06.62	Brunswick Green[13] Maroon Rail Blue	11/1976	Scrapped 17.06.77 BREL Swindon
	D1006	Western Stalwart	BR Swindon 06.07.62	Maroon Rail Blue	04/1975	Scrapped 24.03.77 BREL Swindon
	D1007	Western Talisman	BR Swindon 01.08.62	Maroon Rail Blue	01/1974	Scrapped 24.02.75 BREL Swindon	Was extensively damaged in the Ealing rail disaster of 19 December 1973 and subsequently scrapped.
	D1008	Western Harrier	BR Swindon 04.09.62	Maroon Rail Blue	10/1974	Scrapped 10.10.75 BREL Swindon
	D1009	Western Invader	BR Swindon 24.09.62	Maroon Rail Blue	11/1976	Scrapped 11.78 BREL Swindon
	D1010	Western Campaigner	BR Swindon 15.10.62	Maroon Rail Blue	28/02/77	Preserved by the Diesel & Electric Preservation Group[14]	Standby loco for the Western Tribute Railtour.[15]
	D1011	Western Thunderer	BR Swindon 27.10.62	Maroon Rail Blue	10/1975	Scrapped 12.78 BREL Swindon
	D1012	Western Firebrand	BR Swindon 17.11.62	Maroon Rail Blue	11/1975	Scrapped 04.79 BREL Swindon
	D1013	Western Ranger	BR Swindon 13.12.62	Maroon Rail Blue	28/02/77	Preserved by the Western Locomotive Association	Hauled the Western Tribute Railtour on 26/02/77 (with D1023); the last Western-hauled train on BR.[15]
	D1014	Western Leviathan	BR Swindon 24.12.62	Maroon Rail Blue	08/1974	Scrapped 13.02.75 BREL Swindon
	D1015	Western Champion	BR Swindon 21.01.63	Golden Ochre[13] Maroon Rail Blue	04/01/77	Preserved by the Diesel Traction Group[16]
	D1016	Western Gladiator	BR Swindon 16.02.63	Maroon Rail Blue	12/1975	Scrapped 08.77 BREL Swindon
	D1017	Western Warrior	BR Swindon 15.03.63	Maroon Rail Blue	08/1973	Scrapped 12.03.75 BREL Swindon
	D1018	Western Buccaneer	BR Swindon 02.04.63	Maroon Rail Blue	06/1973	Scrapped 20.03.74 BREL Swindon
	D1019	Western Challenger	BR Swindon 02.05.63	Maroon Rail Blue	05/1973	Scrapped 03.10.74 BREL Swindon
	D1020	Western Hero	BR Swindon 21.05.63	Maroon Rail Blue	06/1973	Scrapped 17.04.74 BREL Swindon
	D1021	Western Cavalier	BR Swindon 17.06.63	Maroon Rail Blue	08/1976	Scrapped 02.79 BREL Swindon
	D1022	Western Sentinel	BR Swindon 16.07.63	Maroon Rail Blue	01/1977	Scrapped 12.78 BREL Swindon
	D1023	Western Fusilier	BR Swindon 23.09.63	Maroon Rail Blue	28/02/1977	Preserved as part of the national collection by the NRM	Hauled the Western Tribute Railtour on 26/02/77 (with D1013); the last Western-hauled train on BR.[15]
	D1024	Western Huntsman	BR Swindon 01.10.63	Maroon Rail Blue	11/1973	Scrapped 14.08.74 BREL Swindon
	D1025	Western Guardsman	BR Swindon 01.11.63	Maroon Rail Blue	10/1975	Scrapped 01.79 BREL Swindon
	D1026	Western Centurion	BR Swindon 24.12.63	Maroon Rail Blue	10/1975	Scrapped 06.08.76 BREL Swindon
	D1027	Western Lancer	BR Swindon 28.01.64	Maroon Rail Blue	11/1975	Scrapped 10.06.76 BREL Swindon
	D1028	Western Hussar	BR Swindon 25.02.64	Maroon Rail Blue	10/1976	Scrapped 06.79 BREL Swindon
	D1029	Western Legionaire	BR Swindon 20.04.64	Maroon Rail Blue	11/1974	Scrapped 29.05.75 BREL Swindon	Renamed Western Legionnaire in 1969, the nameplate being cut to allow the additional letter to be inserted.[17]
	D1030	Western Musketeer	BR Crewe 05.12.63	Maroon Chromatic Blue[12] Rail Blue	04/1976	Scrapped 22.09.76 BREL Swindon
	D1031	Western Rifleman	BR Crewe 20.12.63	Maroon Rail Blue	02/1975	Scrapped 06.10.76 BREL Swindon
	D1032	Western Marksman	BR Crewe 31.12.63	Maroon Rail Blue	05/1973	Scrapped 05.12.74 BREL Swindon
	D1033	Western Trooper	BR Crewe 17.01.64	Maroon Rail Blue	09/1976	Scrapped 04.79 BREL Swindon
	D1034	Western Dragoon	BR Crewe 15.04.64	Maroon Rail Blue	10/1975	Scrapped 20.05.77 BREL Swindon
	D1035	Western Yeoman	BR Crewe 17.07.62	Maroon Rail Blue	01/1975	Scrapped 30.09.76 BREL Swindon
	D1036	Western Emperor	BR Crewe 29.08.62	Brunswick Green[13] Rail Blue	11/1976	Scrapped 24.02.77 BREL Swindon
	D1037	Western Empress	BR Crewe 31.08.62	Brunswick Green[13] Maroon Rail Blue	05/1976	Scrapped 16.02.77 BREL Swindon
	D1038	Western Sovereign	BR Crewe 07.09.62	Brunswick Green[13] Maroon Rail Blue	10/1973	Scrapped 20.11.74 BREL Swindon
	D1039	Western King	BR Crewe 07.09.62	Maroon Rail Blue	07/1973	Scrapped 05.09.74 BREL Swindon	One of the few Westerns to have full yellow ends applied to Maroon livery [12]
	D1040	Western Queen	BR Crewe 20.09.62	Maroon Rail Blue	02/1976	Scrapped 11.08.76 BREL Swindon
	D1041	Western Prince	BR Crewe 10.10.62	Maroon Rail Blue	02/1977	Preserved by the Bury Diesel Group
	D1042	Western Princess	BR Crewe 19.10.62	Maroon Rail Blue	07/1973	Scrapped 18.05.74 BREL Swindon
	D1043	Western Duke	BR Crewe 26.10.62	Maroon Rail Blue	04/1976	Scrapped 10.02.77 BREL Swindon
	D1044	Western Duchess	BR Crewe 12.11.62	Maroon Rail Blue	02/1975	Scrapped 10.09.75 BREL Swindon
	D1045	Western Viscount	BR Crewe 16.11.62	Maroon Rail Blue	12/1974	Scrapped 21.08.75 BREL Swindon
	D1046	Western Marquis	BR Crewe 24.12.62	Maroon Rail Blue	12/1975	Scrapped 10.11.76 BREL Swindon
	D1047	Western Lord	BR Crewe 04.02.63	Maroon Rail Blue	02/1976	Scrapped 09.09.76 BREL Swindon
	D1048	Western Lady	BR Crewe 15.12.62	Maroon Rail Blue	02/1977	Preserved
	D1049	Western Monarch	BR Crewe 14.12.62	Maroon Rail Blue	04/1976	Scrapped 03.02.77 BREL Swindon
	D1050	Western Ruler	BR Crewe 01.01.63	Maroon Rail Blue	04/1975	Scrapped 08.04.76 BREL Swindon
	D1051	Western Ambassador	BR Crewe
	D1052	Western Viceroy	BR Crewe
	D1053	Western Patriarch	BR Crewe
	D1054	Western Governor	BR Crewe
	D1055	Western Advocate	BR Crewe
	D1056	Western Sultan	BR Crewe
	D1057	Western Chieftain	BR Crewe
	D1058	Western Nobleman	BR Crewe
	D1059	Western Empire	BR Crewe
	D1060	Western Dominion	BR Crewe
	D1061	Western Envoy	BR Crewe
	D1062	Western Courier	BR Crewe
	D1063	Western Monitor	BR Crewe
	D1064	Western Regent	BR Crewe
	D1065	Western Consort	BR Crewe
	D1066	Western Prefect	BR Crewe
	D1067	Western Druid	BR Crewe
	D1068	Western Reliance	BR Crewe
	D1069	Western Vanguard	BR Crewe
	D1070	Western Gauntlet	BR Crewe
	D1071	Western Renown	BR Crewe
	D1072	Western Glory	BR Crewe
	D1073	Western Bulwark	BR Crewe

D1029 was originally named Western Legionaire [sic], but renamed Western Legionnaire in 1969, the nameplate being cut to allow the additional letter to be inserted.[18]

Although designated Class 52 under the TOPS scheme and all were still in service when TOPS was introduced in 1973, no Western ever carried its "52 0xx" TOPS number. As withdrawal was already planned when the scheme was introduced and because of the cast number plates, it was not considered cost effective to renumber the locomotives. Some class members did run with the "D" of their number painted over – TOPS classification removed the need for locomotives to indicate their energy type in the running number (D = Diesel, E = Electric).

When the display of destination headcodes on the front of trains was dropped in 1976, the instruction was given for them all to be set to "0000". On many Westerns, the headcode was set to display the locomotive's number in contravention of this directive and most surviving members of the class ran like this until they were scrapped. If used for routing, such reporting numbers would be interpreted as a passenger express terminating on the Southern Region.[19]

• 15 August 1963. Knowle and Dorridge rail crash. No. 1040 Western Queen collided with a freight train, crushing the cab and killing the three traincrew. The locomotive was repaired and returned to service.[21]
• 11 January 1967. St Annes Bristol rail crash. No. 1071 Western Renown in charge of the diverted 12:00 Paddington to Swansea collided with the rear of the 11:45 Paddington to Bristol hauled by No. 1067 Western Druid. The collision resulted in very severe damage being caused to the leading cab of locomotive No.1071, but the three men in the cab escaped injury by moving into the centre of the locomotive. Nineteen passengers required first aid or medical treatment but there were no fatalities or serious injuries. The locomotive was repaired and returned to service.[22][23][24]
• 19 December 1973. Ealing rail crash. No. 1007 Western Talisman derailed while hauling an express passenger train, after an unlocked battery box door fell open, broke off and changed points under the locomotive. Ten people were killed.[25] The locomotive did not return to service.
• 3 January 1976 (Worcester Tunnel). No. 1055 Western Advocate crashed into a stationary parcels train killing the driver and guard of the Western.[26] The locomotive did not return to service.
• 4 October 1976 (Stoke Canon, Exeter). No. 1001 Western Pathfinder was working an overnight parcels train from London Paddington to Penzance when the train was in collision with a workers' van at a level crossing. One workman in the van died in the accident. The locomotive was removed to Exeter St Davids depot. Despite sustaining relatively minor damage, the imminent demise of the entire fleet of Class 52's resulted in condemnation of the locomotive. Up to this point, Western Pathfinder had been a serious contender for preservation.

D1010 on the West Somerset Railway

D1062 on the West Somerset Railway

Seven locomotives have survived into preservation at heritage railways. Two have run on the mainline in preservation with D1015 been passed to operate on the mainline since 2002.[27][28] D1062 made a brief appearance in 1980 during the Rocket 150 parade at Rainhill.

D1022 Western Sentinel was a candidate for preservation and was planned to be purchased by the DTG (Diesel Traction Group), but it was scrapped. D1015 Western Champion was purchased for preservation.[29]

In 1979 Hornby Railways launched its first version of the BR Class 52 (type 4) Western in OO gauge.[31]

• Krauss-Maffei ML 2200 C'C', RENFE Class 340, contemporary twin engined, twin transmission C'C' diesel hydraulic locomotives
• Voith Maxima, modern (2000s) single engined, single transmission high power diesel hydraulic locomotive

Wikimedia Commons has media related to British Rail Class 52.

• Birt, David (1988). The Class 52s: A Tribute to the Westerns. OPC. ISBN 9780860934240. OCLC 315783582.
• Chapman, Chris (2002). Western Glory. Waterfront. ISBN 9780946184996. OCLC 786126155.
• Clarke, David; Jennison, John (2007). Diesels in Depth: Westerns. Ian Allan. ISBN 9780711032507. OCLC 159634206.
• Clough, David N. (2011). Hydraulic vs Electric: The battle for the BR diesel fleet. Ian Allan. ISBN 978-0-7110-3550-8.
• Cross, David (2012). Fifty Years of the Westerns. Ian Allan. ISBN 9780711036581. OCLC 794814820.
• Curtis, Adrian (2001). Western Liveries. A & C Services. ISBN 9780954021313. OCLC 49299854.
• Curtis, Adrian N. (2011–2012). Westerns Vols 1/2/3. Western Legacy Publications.
• Curtis, Adrian N. (2002). Western Dawn. A&C Services.
• Curtis, Adrian N. (2000). Cast of Thousands. A&C Services.
• Curtis, Adrian N. (2012). Final Salute '77. Western Legacy Publications.
• Curtis, Adrian N. (2012). Spirit of '76. Western Legacy Publications.
• Curtis, Adrian N. (2012). Indian Summer '75. Western Legacy Publications.
• Curtis, Adrian N. (2012). Tracks of my Years. Western Legacy Publications.
• Curtis, Adrian N. (2012). Teenage Lament '74. Western Legacy Publications.
• Curtis, Adrian N. (2010–2012). Western Power. Western Legacy Publications.
• Curtis, Adrian N. (1996–2012). Classic Diesels & Electrics. Western Legacy Publications.
• Curtis, Adrian N. (2010–2012). Diesel Hydraulics Illustrated. Western Legacy Publications.
• Dowle, Stephen (2015). Class 52 Westerns: The Twilight Years. Amberley Publishing. ISBN 9781445648989. OCLC 919481086.
• Ford, H.L.; Preedy, Norman E. (1976). The Westerns: British Rail Class 52 Diesel Hydraulics. Bradford Barton. ISBN 9780851532738. OCLC 2797567.
• Huntriss, Derek (2003). The Heyday of the Westerns. Ian Allan. ISBN 9780711029811. OCLC 52530865.
• McManus, Michael. Ultimate Allocations, British Railways Locomotives 1948 – 1968. Wirral. Michael McManus.
• Nicholas, D.; Montgomery, S. (2005). Profile of the Westerns. Ian Allan. ISBN 9780860931164. OCLC 10723140.
• Preedy, Norman (2015). British Railway Diesel Memories: The Western Class 52s. Book Law Publications. ISBN 9781909625457.
• Preedy, Norman E. (1977). Book of the Westerns. Peter Watts. ISBN 9780906025031. OCLC 650233739.
• "Where 'Westerns' went". Rail Enthusiast. EMAP National Publications. February–March 1982. p. 54. ISSN 0262-561X. OCLC 49957965.
• Kelly, Peter (January 1983). "Maybach music!". Rail Enthusiast. EMAP National Publications. pp. 14–17. ISSN 0262-561X. OCLC 49957965.
• "Western Lady". Rail Enthusiast. EMAP National Publications. November 1983. p. 21. ISSN 0262-561X. OCLC 49957965.