British Rail DHP1

4 ft 8+1⁄2 in (1,435 mm) standard gaugeWheel diameter3 ft 3+1⁄2 in (1.003 m)Minimum curve4 chains (260 ft; 80 m)Wheelbase34 ft 0 in (10.36 m)Length46 ft 3+1⁄2 in (14.11 m)Width9 ft 0 in (2.74 m)Height12 ft 6 in (3.81 m)Loco weight56 long tons (57 t; 63 short tons)Fuel capacity600 imp gal (2,700 L; 720 US gal)Prime moverRolls-Royce C8TFL, 4 offTransmissionHydraulicMU workingNot fittedTrain heatingSteamTrain brakesVacuum

Performance figures
Maximum speed	90 mph (140 km/h)
Power output	Engines: 375 hp (280 kW) at 1,800 rpm × 4 At rail: 1,200 hp (890 kW)
Tractive effort	Maximum: 37,500 lbf (167 kN)

Career
Operators	British Railways
Disposition	Scrapped

DHP1, meaning Diesel Hydraulic Prototype number 1, was a prototype Type 3 mainline diesel locomotive built between 1962 and 1963 by Clayton to demonstrate their wares to British Railways. It was designed for mixed traffic work, being equipped with steam heating facilities for working passenger trains. It was painted red, with the cab area above bonnet-level height painted cream.

Visually similar to their Class 17 Type 1 product, though longer, and with the radiator grilles in the ends of the engine covers rather than the sides. The locomotive saw little service, mainly around the International Combustion works in Derby. The locomotive was broken up by Clayton's in April 1967.