GB562371A - Improvements in or relating to air brakes for aircraft - Google Patents

Abstract

562,371. Coutrolling aircraft. FAIREY AVIATION CO., Ltd., and YOUNGMAN, R. T. July 3, 1942, No. 9220. [Class 4] An aircraft having an air brake of the kind described in Specification 562,365, wherein a flap is adapted to be projected into or withdrawn from the airstream by a bellows device in communication with the throat of a venturi-tube fitted with a butterfly valve, has a pipe g from a venturi-tube f connected to the front end of a second venturi-tube, the throat of which is connected by a pipe to a bellows device for actuating a flap a, while another passage n leads from the rear end of the second venturitube to a bellows device for actuating a second flap c opposite to the first flap. A butterfly valve 12 in the venturi-tube f enables the bellows devices to be put under pressure or suction at will. The two flaps a, c may, as shown, be mounted above and below the trailing portion of a wing and the lower flap c may be on an auxiliary surface d normally nested within a recess beneath the wing and adapted to' be lowered as described in Specifications 461,157, 467,465 or 493,391. A soft rubber ring m normally seals the joint between the passage n and the second venturi-tube and when the surface d is lowered the joint is broken and the two flaps a, c are withdrawn to inoperative position. Alternatively, the passage n may have a flexible connection to the second venturitube so that both flaps a, c may be kept projected if required. To prevent unequal movement of the flaps they are connected by cables p, q, Fig. 5, to two spring-urged slides r, s of insulating material carrying contacts v, w. Should the movements be unequal, the circuit of a solenoid x is closed to cause its armature y to open the butterfly valve 12 and retract both flaps, for which purpose the armature is linked to the control lever 11 which actuates the valve 12. Alternatively, the slides r, s may actuate hydraulic or pneumatic valves controlling a jack device for moving the lever 11. The cable q in the case of a flap on the movable surface d, is led alongside one of the links by which the surface is raised and lowered.