hovertrain

thumb|right|250px|Duke University Medical Center Patient Rapid Transit|Duke Hospital PRT thumb|right|250px|Narita Airport Terminal 2 Shuttle System A hovertrain, also known as tracked hovercraft (UK) or tracked air-cushion vehicle (US), is a vehicle that is suspended on a cushion of air, similar to a hovercraft, but operates on a guideway. Unlike conventional trains, which use steel wheels on steel rails, hovertrains use air-based lifting systems and a smooth paved surface known as the track or guideway. The concept aims to eliminate rolling resistance and allow very high performance, while also simplifying the infrastructure needed to lay new lines. The first hovertrain was developed by Jean Bertin in the early 1960s in France, where they were marketed as the Aérotrain before being abandoned by the French government.

==History== Hovertrains were seen as a relatively low-risk and low-cost way to develop high-speed inter-city train service, in an era when conventional rail seemed stuck to speeds around or less. By the late 1960s, major development efforts were underway in France, the UK and the USA. While they were being developed, British Rail was running an extensive study of the problems being seen at high speeds on conventional rails. This led to a series of new high-speed train designs in the 1970s, starting with their own APT. Although the hovertrains still had reduced infrastructure costs compared to the APT and similar designs like the TGV, in practice this was offset by their need for entirely new lines. Conventional wheeled trains could run at low speed on existing lines, greatly reducing capital expenditures in urban areas. Interest in hovertrains waned, and major development had ended by the mid-1970s.