British Rail DP1

English Electric DELTIC prototype
The nose end of DP1 at Locomotion
Type and origin
Power typeDiesel-electric
BuilderEnglish Electric at Dick, Kerr Works, Preston
Serial numberEE: 2003
Build date1955
Specifications
Configuration:
 • UICCo'Co'
Gauge4 ft 8 12 in (1,435 mm)
Wheel diameter3 ft 7 in (1.09 m)
Length66 ft
Loco weight106 long tons (108 t)
Prime moverNapier Deltic D18-25 (2 off)
Traction motorsEE 526/A, 6 off
Cylinders18 × 2
TransmissionDiesel Electric
Train heatingStone-Vapor/Clarkson steam generator
Performance figures
Top speed90 mph (140 km/h)
106 mph (171 km/h) from 1956
Power output3,300 hp (2,500 kW)
Tractive effort90 mph gearing: 60,000 lbf (266.89 kN)
106 mph gearing: 52,500 lbf (233.53 kN)
Career
Railroad(s)British Railways
Power classType 5
NumberDP1
Official nameDELTIC
RetiredMarch 1961
Dispositionto Science Museum, London, April 1963

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.