British Rail DP1

DP1, or Prototype Deltic is a demonstrator locomotive built by English Electric in 1955. This locomotive resulted in 22 similar locomotives being ordered by British Rail, which became their Class 55.

English Electric DELTIC prototype
The nose end of DP1 at Locomotion
Type and origin Power type Diesel-electric Builder English Electric at Dick, Kerr Works, Preston Serial number EE: 2003 Build date 1955
Specifications Configuration: ​  • UIC Co'Co' Gauge 4 ft 8 1⁄2 in (1,435 mm) Wheel diameter 3 ft 7 in (1.09 m) Length 66 ft Loco weight 106 long tons (108 t) Prime mover Napier Deltic D18-25 (2 off) Traction motors EE 526/A, 6 off Cylinders 18 × 2 Transmission Diesel Electric Train heating Stone-Vapor/Clarkson steam generator
Performance figures Top speed 90 mph (140 km/h) 106 mph (171 km/h) from 1956 Power output 3,300 hp (2,500 kW) Tractive effort 90 mph gearing: 60,000 lbf (266.89 kN) 106 mph gearing: 52,500 lbf (233.53 kN)
Career Railroad(s) British Railways Power class Type 5 Number DP1 Official name DELTIC Retired March 1961 Disposition to Science Museum, London, April 1963