| BR Class 52 |
| TOPS numbers |
Never carried |
| Early numbers |
D1000–D1073 |
| Builder |
BR Swindon , BR Crewe |
| Introduced |
1962-1964 |
| Wheel Arrangement |
C-C |
| Weight |
108 tons (UK) |
110 t |
| Height |
12 ft 11.75 in |
3.956 m |
| Width |
8 ft 8 in |
2.64 m |
| Length |
68 ft 0 in |
20.73 m |
| Wheel Dia. |
3 ft 7 in |
1.09 m |
| Wheel Base |
54 ft 8 in |
16.66 m |
| Minimum radius |
4.5 chains |
90.5 m |
| Maximum speed |
90 mph |
145 km/h |
| Engine |
2 x Maybach MD655 |
| Engine output |
2 x 1,350 hp |
2 x 1010 kW |
| Max. Tractive Effort |
66,700 lbf |
297 kN |
| Power at Rail |
2,000 hp |
1,490 kW |
| Brake type |
Air & vacuum |
| Brake force |
50 tons force |
500 kN |
| Route availability |
7 |
| Fuel Tank |
850 imperial gallons |
3,860 litres |
| Heating type |
Steam |
| Multiple working |
Not equipped |
British Rail assigned Class 52 to the class of 74 large Type 4 diesel-hydraulic locomotives built for the Western Region of British Railways between 1961 and 1964. All were given two-word names with the first word being Western, and thus the type became known as Westerns.
The Diesel-Hydraulic Experiment
When switching to diesel traction, as part of the Modernisation Plan of the 1950s, BR designed and commissioned designs for a large number of locomotive types. At this time (and arguably right up until Sectorisation in the 1980s), 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 utilising diesel-hydraulic traction, commissioning three classes of locomotives - the Westerns, and the lesser-powered Hymeks and Warships.
The theoretical advantage of diesel-hydraulic was simple—it resulted in a lighter locomotive than equivalent diesel-electric transmission. This resulted in better power/weight ratio, and decreased track wear. Unfortunately, it had two key disadvantages:
- The technology was proven in continental Europe, particularly Germany, but was new to the UK.
- 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.
Thus the Westerns—high-powered locomotives for top link Western Region services—needed two diesel engines to achieve the required power output. Prototypes sited the engines behind the driving cab, but drivers found this too noisy; moving the engines centrally meant making the locomotive heavier, removing some of the design's advantage.
Whilst the Class was successful, it was also non-standard; the early 1970s saw the decision taken to retire all the diesel-hydraulic types. Class 47s and 50s began to take over on the Western Region, whilst the arrival of the High Speed Train was the final nail in the coffin for the Westerns. The final class member was withdrawn in February 1977.
Names and numbers
All of the Westerns were named, as in the following table:
| Number |
Name |
Builder |
Disposition |
| D1000 |
Western Enterprise |
BR Swindon |
Scrapped |
| D1001 |
Western Pathfinder |
BR Swindon |
Scrapped |
| D1002 |
Western Explorer |
BR Swindon |
Scrapped |
| D1003 |
Western Pioneer |
BR Swindon |
Scrapped |
| D1004 |
Western Crusader |
BR Swindon |
Scrapped |
| D1005 |
Western Venturer |
BR Swindon |
Scrapped |
| D1006 |
Western Stalwart |
BR Swindon |
Scrapped |
| D1007 |
Western Talisman |
BR Swindon |
Scrapped |
| D1008 |
Western Harrier |
BR Swindon |
Scrapped |
| D1009 |
Western Invader |
BR Swindon |
Scrapped |
| D1010 |
Western Campaigner |
BR Swindon |
Preserved |
| D1011 |
Western Thunderer |
BR Swindon |
Scrapped |
| D1012 |
Western Firebrand |
BR Swindon |
Scrapped |
| D1013 |
Western Ranger |
BR Swindon |
Preserved |
| D1014 |
Western Leviathan |
BR Swindon |
Scrapped |
| D1015 |
Western Champion |
BR Swindon |
Preserved |
| D1016 |
Western Gladiator |
BR Swindon |
Scrapped |
| D1017 |
Western Warrior |
BR Swindon |
Scrapped |
| D1018 |
Western Buccaneer |
BR Swindon |
Scrapped |
| D1019 |
Western Challenger |
BR Swindon |
Scrapped |
| D1020 |
Western Hero |
BR Swindon |
Scrapped |
| D1021 |
Western Cavalier |
BR Swindon |
Scrapped |
| D1022 |
Western Sentinel |
BR Swindon |
Scrapped |
| D1023 |
Western Fusilier |
BR Swindon |
Preserved |
| D1024 |
Western Huntsman |
BR Swindon |
Scrapped |
| D1025 |
Western Guardsman |
BR Swindon |
Scrapped |
| D1026 |
Western Centurion |
BR Swindon |
Scrapped |
| D1027 |
Western Lancer |
BR Swindon |
Scrapped |
| D1028 |
Western Hussar |
BR Swindon |
Scrapped |
| D1029 |
Western Legionaire |
BR Swindon |
Scrapped |
| D1030 |
Western Musketeer |
BR Crewe |
Scrapped |
| D1031 |
Western Rifleman |
BR Crewe |
Scrapped |
| D1032 |
Western Marksman |
BR Crewe |
Scrapped |
| D1033 |
Western Trooper |
BR Crewe |
Scrapped |
| D1034 |
Western Dragoon |
BR Crewe |
Scrapped |
| D1035 |
Western Yeoman |
BR Crewe |
Scrapped |
| D1036 |
Western Emperor |
BR Crewe |
Scrapped |
| D1037 |
Western Empress |
BR Crewe |
Scrapped |
| D1038 |
Western Sovereign |
BR Crewe |
Scrapped |
| D1039 |
Western King |
BR Crewe |
Scrapped |
| D1040 |
Western Queen |
BR Crewe |
Scrapped |
| D1041 |
Western Prince |
BR Crewe |
Preserved |
| D1042 |
Western Princess |
BR Crewe |
Scrapped |
| D1043 |
Western Duke |
BR Crewe |
Scrapped |
| D1044 |
Western Duchess |
BR Crewe |
Scrapped |
| D1045 |
Western Viscount |
BR Crewe |
Scrapped |
| D1046 |
Western Marquis |
BR Crewe |
Scrapped |
| D1047 |
Western Lord |
BR Crewe |
Scrapped |
| D1048 |
Western Lady |
BR Crewe |
Preserved |
| D1049 |
Western Monarch |
BR Crewe |
Scrapped |
| D1050 |
Western Ruler |
BR Crewe |
Scrapped |
| D1051 |
Western Ambassador |
BR Crewe |
Scrapped |
| D1052 |
Western Viceroy |
BR Crewe |
Scrapped |
| D1053 |
Western Patriarch |
BR Crewe |
Scrapped |
| D1054 |
Western Governor |
BR Crewe |
Scrapped |
| D1055 |
Western Advocate |
BR Crewe |
Scrapped |
| D1056 |
Western Sultan |
BR Crewe |
Scrapped |
| D1057 |
Western Chieftain |
BR Crewe |
Scrapped |
| D1058 |
Western Nobleman |
BR Crewe |
Scrapped |
| D1059 |
Western Empire |
BR Crewe |
Scrapped |
| D1060 |
Western Dominion |
BR Crewe |
Scrapped |
| D1061 |
Western Envoy |
BR Crewe |
Scrapped |
| D1062 |
Western Courier |
BR Crewe |
Preserved |
| D1063 |
Western Monitor |
BR Crewe |
Scrapped |
| D1064 |
Western Regent |
BR Crewe |
Scrapped |
| D1065 |
Western Consort |
BR Crewe |
Scrapped |
| D1066 |
Western Prefect |
BR Crewe |
Scrapped |
| D1067 |
Western Druid |
BR Crewe |
Scrapped |
| D1068 |
Western Reliance |
BR Crewe |
Scrapped |
| D1069 |
Western Vanguard |
BR Crewe |
Scrapped |
| D1070 |
Western Gauntlet |
BR Crewe |
Scrapped |
| D1071 |
Western Renown |
BR Crewe |
Scrapped |
| D1072 |
Western Glory |
BR Crewe |
Scrapped |
| D1073 |
Western Bulwark |
BR Crewe |
Scrapped |
