A vessel riding on a cushion of air formed under it. It is very manoeuvrable and is also amphibious. There are two types of hovercrafts: the fully skirted and the sidewall. The most remarkable of these crafts was British Hovercraft SRN4. This large, gas turbine propelled passenger/vehicle ferry went into service in 1968. In its original configuration, the SRN4 could carry 30 cars on the central vehicle deck and 254 passengers in two identical side cabins. Power was provided to the four lift fans and pylon mounted propellers by four Rolls Royce Proteus gas turbines and speeds of up to 60 knots could be achieved.