APT-E (Advanced Passenger Train Experimental) was the prototype of the Advanced Passenger Train tilting train unit. It was powered by gas turbines, the only multiple unit so powered that was used by British Rail. The APT-E consisted of two driving power cars (PC1 and 2) and two trailer cars (TC1 and 2). Each power car was equipped with four Rover- built Leyland 2S/350 gas turbines (and a fifth for auxiliary power supplies), these initially produced 300 HP each but were progressively uprated to 330 HP. The unit was only intended for testing and was never used in ordinary public service, although it did carry office staff and the occasional dignitaries on trial runs. When its period of testing was complete, in June 1976, it was sent to the National Railway Museum, York for preservation. It is now based at the NRM's Locomotion museum in Shildon. Behind is the blue diesellocomotive DP1, commonly known as Deltic, a prototype 3,300 hp (2,500 kW) demonstrator locomotive employing two Napier Deltic engines, built by English Electric in 1955. The high power of the locomotive at an acceptably low axleload resulted in 22 similar locomotives being ordered by British Railways for use on East Coast Main Line express passenger services; the serial production of which became the British Rail Class 55.
