GB517422A - Improvements in or relating to aircraft - Google Patents

Abstract

517,422. Controlling aircraft. WESTLAND AIRCRAFT, Ltd., and PETTER, W. E. W. July 19, 1938, No. 21362. [Class 4]- The Handley-Page or like leading edge slat of an aeroplane wing is adapted to be tilted through a greater angle in relation to the main wing than that which is required to give maximum lift in order to act as a drag, particularly during diving. The. slats also may be interconnected with other known forms of drag producing elements such as rear flaps, split ailerons, or surfaces normally housed in the wing near the leading edge and adapted to be projected below the wing substantially normal to it. Fig. 1 shows a slat b pivoted at its leading edge to channel section members d guided by rollers e, f, an oil ram g pivoted between a pair of members d enabling the slat to be tilted through about 30 degrees. The slat may be pivoted to the members. d at an intermediate point of its chord and the ram may act on its leading edge, or as shown in Fig. 3 the oil ram may be replaced by a screw jack j the rear end of which can be rotated by a splined shaft m under control of the pilot. In other modifications a ram acts on the centre of a pair of toggle links connected to the slat and guide members d or it acts on a lever pivoted at one end to a member d. and sliding at its other end in a slotted member attached to the slat. Fig. 7 shows a slat having pin-and-slat connections 9, 10 with the members d at the forward end and intermediate link connections, 7. A ram g acting at the connection 8 of the link and slat a second link may replace the pin-and-slot connection. Fig. 9 shows a ram which actuates a rack 19 to turn a toothed quadrant 18 having lever arms 17 connected to the slat by links 15, the links being in the dead-centre position at both extreme ends of the movement. The rack and quadrant may be replaced by chains and sprockets or by worm and worm wheels. In another modification a quadrant secured directly to the slat is engaged by a worm on a shaft driven by bevel gear carried by the members d. The bevel gear is driven by splined telescopic shafts driven by bevel or chain gear under control of the pilot. In another modification the slats are not tiltable relative to the members d but the latter are tiltable by a ram. Fig. 14 shows a slat mounted on pairs of links one of each pair being constituted by a ram g. In all cases the lower part 7 of the slat remains in contact with the leading edge of the wing when acting as an air brake. In a form similar to Fig. 1 the front part of the slat is fixed to the members d and only the rear part is tiltable.