Aerodynamic Characteristics Of Air Cushioned Models At Very Low Ground Clearances And At Free Stream Dynamic Pressures Exceeding Cushion Pressure

Air-cushion models employing peripheral jet and plenum cushions of circular, rectangular, and side-by-side planforms were tested in hovering and at forward speed in the 17-foot (5.18-meter) test section of the Langley 300-MPH 7- by 10-foot tunnel. The principal purpose of these tests was to study the characteristics of air cushions when freestream dynamic pressure exceeded air-cushion pressure. Also examined were the hovering performance and the effects of moving ground belt, crosswind, height, and angle of attack. For the configurations tested, there was no significant loss in cushion performance when free-stream dynamic pressure exceeded cushion pressure.