GB576125A - Improvements in aircraft supporting surfaces - Google Patents

Abstract

576,125. Controlling aircraft. PHILLIPS & POWIS AIRCRAFT, Ltd., and HEAL, L. C. July 24, 1942, No. 10399. [Class 4] An aircraft wing tip is pivoted about a fore- and-aft axis so as to be turnable upwards or downwards into a vertical position, and split flaps at' the trailing edges of the tip portions are independently or differentially operable while the tip portions are in their vertical position. The tips may be movable simultaneously with retractable landing gear. Fig. 1 shows a plan of a swept-back wing having a tip portion 21 which is normally locked in line with the wing but can be turned about a hinge 22 into a vertical plane. Control surfaces 23' are provided' on the main part of the wing. The rear edge of the tip mounts a split flap 24, the flaps on the two sides of the machine being operable independently for manoeuvring the aircraft. Owing to the hinge 26 of each split flap being rearwardly inclined when the tip is in the vertical position, any opening of the flap results not only in an increased drag but also introduces a downward force on the wing. When the main wing is at a dihedral angle, the wing tip may be turned upwards into a position perpendicular to it. Fig. 7 shows hydraulic means for simultaneously raising the wing tip 21 and lowering a retractable undercarriage for which purpose they are respectively connected to pistons 32, 29 working in a cylinder 32 divided by a partition 28 and having ports 38, 39, 40. A single control valve may effect the movement and locking of the pistons or separate valves may be used. The tips 21 and undercarriage may be independently movable. The invention is particularly applicable to a tail-less aircraft, elevators and flaps being provided on the main part of the wing and the adjustable surfaces on the tips acting as ailerons during normal flight.