British Rail 10100

British Railways 10100
The Fell Diesel at Derby Works in June 1957
Type and origin Power type Diesel-mechanical Builder LMS, Derby Works Build date 1951
Specifications Configuration: ​  • Whyte 4-8-4  • UIC 2′D2′ Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Leading dia. 39 in (0.991 m) Driver dia. 51 in (1.295 m) Minimum curve 5 chains (101 m) Wheelbase 41 ft 4 in (12.60 m) Length 50 ft 0 in (15.24 m) Width 9 ft 0 in (2.74 m) Height 13 ft 0 in (3.96 m) Loco weight 120 long tons (122 t; 134 short tons) Fuel capacity 720 imp gal (3,300 L; 860 US gal) Coolant cap. 60 imp gal (270 L; 72 US gal) Water cap 500 imp gal (2,300 L; 600 US gal) Prime mover Paxman 12RPH, x 4 Cylinder size 7 in × 7+3⁄4 in (178 mm × 197 mm) Transmission Vulcan Sinclair SCRD fluid; Fell central gearbox Train heating Steam generator Train brakes Vacuum
Performance figures Maximum speed 84 mph (135 km/h) Power output 2,000 bhp (1,500 kW) at 1,500 rpm Tractive effort 25,000 lbf (111 kN) Brakeforce 38 long tons-force (380 kN)
Career Operators British Railways Power class 6P5F, later Type 4 Numbers 10100 Nicknames Fell Diesel Locomotive Withdrawn 15 October 1958 Scrapped Derby Works, July 1960

British Railways 10100 was an unusual experimental diesel locomotive known informally as The Fell Diesel Locomotive (after Lt. Col. L.F.R. Fell, who was one of the designers). It was the joint production of Davey Paxman & Co, Shell Refining & Marketing Co and Lt-Col L.F.R. Fell, built for them by the London, Midland and Scottish Railway at Derby. Sir Harry Ricardo was also involved. By the time it emerged in 1950, nationalisation had taken place and it carried British Railways livery. The locomotive had six diesel engines, four of them used for traction. The auxiliary engines drove the pressure-chargers for the main engines and the purpose of this arrangement was to enable the main engines to deliver very high torque at low crankshaft speed.