Gas turbine on and off to run it only at high efficiency. The emergence of the continuously variable transmission may also alleviate the responsiveness problem. Turbines have historically been more expensive to produce than piston engines, though this is partly because piston engines have been mass-produced in huge quantities for decades, while small gas turbine engines are rarities; however, turbines are mass-produced in the closely related form of the turbocharger. The turbocharger is basically a compact and simple free shaft radial gas turbine which is driven by the piston engine's exhaust gas. The centripetal turbine wheel drives a centrifugal compressor wheel through
Gas turbine locomotive of the Advanced Passenger Train, was turbine-powered. Like the French TGV, later models were electric. This choice was made because British Leyland, the turbine supplier, ceased production of the model used in the APT-E. ALCO-GE built a prototype oil-fired gas turbine-electric locomotive in 1948. After demonstration runs it was acquired by Union Pacific, who were seeking a more powerful alternative to diesel for transcontinental trains. Union Pacific ran a large fleet of turbine-powered freight locomotives starting in the early 1950s. These were widely used on long-haul routes, and were cost-effective despite their poor fuel economy, due to their use of