The TGV 001 Turbotrain
The TGV 001 turbotrain was a test train for a vast research program encompassing traction, vehicle dynamics, braking, aerodynamics, signalling, and other technologies that needed to be developed to allow higher speeds. Only one was ever built, although it was originally planned to build a second version equipped with an active tilt system. The studies for the tilting version were completed, but it never reached construction because of technical difficulties with fitting the tilt system.
The TGV 001 consisted of two power cars with three trailers in between, the whole trainset permanently coupled together. All axles were powered by electric motors, with the advantage of low axle loads and a high power-to-weight ratio. Electric traction also made possible dynamic braking, especially effective at high speeds. Each power car had a pair of turbines (the TURMO IIIG and then the TURMO X, used in Sud Aviation's Super Frelon helicopter) which ran at constant speed. They were connected to a reductor stage, whose output shaft drove an alternator. Besides the turbine drive, the power cars had control gear for the traction motors, dynamic brake grids, signalling and braking equipment, etc.
The TGV001 was articulated, with adjacent vehicles riding on a common truck. This afforded a greater stability (by coupling the dynamics of carbodies) and made space for a pneumatic secondary suspension placed level with the centre of gravity, thus reducing roll in curves. In 5227 test runs covering almost half a million kilometres, the TGV 001 turbotrain exceeded 300 km/h (186 mph) on 175 runs and reached a top speed of 318 km/h (198 mph) on 8 December 1972. This was (and still is) the world speed record for a non-electric train. The TGV 001 test campaign was an invaluable part of project C03, proving new concepts in a realistic environment and giving extensive engineering data on high-speed operation.
Read more about this topic: Development Of The TGV