Improvements in or relating to gas cushion vehicles

1,138,532. Air cushion vehicles. HOVERCRAFT DEVELOPMENT Ltd. 14 April, 1966 [21 April, 1965], No. 16878/65. Heading B7K. An air cushion vehicle is formed at its lower side with a bevelled face 11a, to which is secured in air-tight relationship a flexible, porous duct 20 supplied with pressure air from ducts 18, whereby air may pass through the duct wall to form and maintain the cushion. The degree of porosity may be constant around the periphery of the vehicle or it may differ. The duct is enclosed and surrounded by a wall 12, and in the embodiment shown this is a double wall through which air is discharged to form a peripheral curtain. In such embodiment duct 20 need not be porous. A supplementary supply of cushion air may be provided by a duct 25.