High-speed rail
High-speed rail is a type of rail transport that operates significantly faster than traditional rail traffic, using an integrated system of specialized rolling stock and dedicated tracks. While there is no single standard that applies worldwide, new lines in excess of and existing lines in excess of are widely considered to be high-speed, with some extending the definition to include lower speeds in areas for which these speeds still represent significant improvements. The first such system began operations in Japan in 1964 and was widely known as the bullet train. High-speed trains normally operate on standard gauge tracks of continuously welded rail on grade-separated right-of-way that incorporates a large turning radius in its design.
Eurostar
The trains are essentially modified TGV sets, and can operate at up to on high-speed lines, and in the Channel Tunnel. It is possible to exceed the 300-kilometre-per-hour speed limit, but only with special permission from the safety authorities in the respective country.
Speed limits in the Channel Tunnel are dictated by air-resistance, energy (heat) dissipation and the need to fit in with other, slower trains. The trains were designed with Channel Tunnel safety in mind, and consist of two independent "half-sets" each with its own power car. In the event of a serious fire on board while travelling through the tunnel, passengers would be transferred into the undamaged half of the train, which would then be detached and driven out of the tunnel to safety.
If the undamaged part were the rear half of the train, this would be driven by the Chef du Train, who is a fully authorised driver and occupies the rear driving cab while the train travels through the tunnel for this purpose.