GB778675A - Improvements in air brakes for aircraft - Google Patents

Abstract

778,675. Aircraft air brakes. ARMSTRONG WHITWORTH AIRCRAFT, Ltd., Sir W. G. July 15, 1955 [Nov. 19, 1954], No. 33511/54. Class 4. [Also in Group XXIX] An aircraft air brake includes a flap 15 hinged on each side of the aircraft body forward of the tail and carried by two hinge members 12, 13, Fig. 4, one, 12, having one end pivoted to the body and the other end pivoted to the flap at 14 substantially at its centre of pressure, the other member 13 being pivoted to the body and flap at points spaced from the pivots of the member 12, with means for moving the two flaps simultaneously, the hinge members being arranged so that the centre of pressure of each flap moves initially, radially and then substantially radially with slightly increasing deviation from the radial direction. In Fig. 4, the arrow N points to the nose. Each member 13 is one part of a bell crank lever 13, 19, pivoted on a bracket 18, the arm 19 being pivoted to the body of a hydraulic valve 28 the valve rod 27 of which is attached by a bell crank lever to a rod 25 pivoted to a lever 24 mounted on a rotatable shaft. Each valve 28 controls a jack 20 operating between a pivot 21 on the fuselage and the flap 15, so that rotation of shaft 24 causes actuation of the jacks 20 until the valve bodies 28 are moved to re-centre the valve rods 27. In Fig. 5, each flap 31 is pivoted on two members 32, 33, the former being pivoted to the fuselage on a bracket 34, and the latter mounted on a shaft 35. A control rod 44 operates the piston 41 of a valve 40 pivoted at 39 to one member 33, the valve controlling the operating jack 38. In this embodiment, the flap 31 and hinge member 32 together form a smooth fairing in the retracted position shown in full lines, see Fig. 8 (not shown).