Leyland 2S/350 gas turbine

The Leyland 2S/350 was an experimental recuperated gas turbine engine developed by Leyland Motors and then British Leyland to power heavy road vehicles. It grew out of the 2S/150, a smaller turbine that Rover had adapted from its Rover-BRM Le Mans racing work. After Leyland bought Rover in 1967, the basic layout was scaled up in 1968 for articulated lorries needing roughly 350 to 400 brake horsepower. The engine used a gas generator with a separate free-running low-pressure turbine geared ten to one to the drive shaft, ceramic disc heat exchangers to recover exhaust heat, and a cast iron housing in place of costlier stainless steel. The first version used two heat exchanger discs and the Mark II a single larger disc. Six trucks with the Mark II engine went out for road trials in the early 1970s, and the engine also powered the British Rail APT-E train. Rising fuel costs after the 1973 oil crisis and unsolved sealing problems in the heat exchangers ended development, and it was only ever used experimentally.