These type of trains are becoming more popular especially for travel within countries with vast distances between cities. High speed trains usually operate at speeds exceeding 200km/ hr with trains such as the TGV in France exceeding speeds of 300 km/ hr. The first example of a commercially successful high speed train was Japan’s Shinkansen which began operations in 1964. France’s TGV achieved speeds of 574.8km/hr twice the take off speed of a Boeing 727 liner under test conditions in 2007. The TGV however runs on a commercially operational speed of 300-320km/ hr. The highest operational speed for high speed trains used for commercial operations are the Beijing- Tianjin and Wuhan-Guangzhou high speed rails in China, running at 350km/hr. High speed rails have been found to be cost effective when the distances do not exceed 500 to 600km when compared to air travel covering the same distances. The extra time spent for airport check-in and boarding may add an extra two hours to the overall travel time. Also the cost of fuelling the plane for takeoff and duration of the journey also adds to the cost efficiency of high speed trains. As travel distances increase, the cost efficiency of planes increase as the cost of fuel becomes less of the total cost of operating an aircraft. Some high speed rails employ tilting technology to improve the stability of the train as it passes through curved tracks. Tilting technology involves superelevation which allows both high speed and low speed traffic to use the same tracks, though not simultaneously, and produces a more comfortable ride for the passengers.