GB1286127A - Improvements in or relating to ground effect machines - Google Patents

Abstract

1286127 Gas-cushion vehicle BERTIN & CIE 10 Oct 1969 [10 Oct 1968] 49978/69 Heading B7K A gas-cushion vehicle, particularly one guided by fixed tracks, is provided with means for varying a barrier at the front of a gas cushion to counteract increasing inrush of ambient air as the speed of the vehicle increases. Gas cushion 9 is bounded at the front by a fixed vertical wall 16 which bears a further wall 17 pivoted at 18 such that when the wall 17 is vertical it extends below the wall 16. When the vehicle is at rest the wall 17 is held against stop 21 by spring 19, but as the speed of the vehicle increases cushion pressure will increase, tending to turn the wall 17 clockwise (as viewed in Fig. 2) so as to reduce the gap beneath the wall 17, and this will prevail over the increasing ram air pressure. In a similar construction, Fig. 3, wall 25 extends beyond pivot axis 26 into a chamber 28, dividing the chamber into two parts. That part to the rear of the wall 25 is connected by a duet 31 to air intake 3 of the vehicle, so that with increasing speed of the vehicle the pressure in that part is progressively reduced, tending to counteract the torque on the wall 25 caused by ram air pressure. Alternatively, Fig. 6, the inrush of air into the cushion space may be controlled by a fluid curtain, issuing from a nozzle 41 formed by front wall 39, curtain thickness increasing with the speed of the vehicle. This may be achieved by feeding the nozzle 41 from an air intake 47 at the front of the vehicle, or by feeding it from a compressor (45, Fig. 7, not shown) whose power supply is governed by a rheostat (47) controlled by a piston (51) which is pushed progressively backwards by ram air against a spring (52) as the speed of the vehicle increases.