GB787011A - A jet deflecting flap for jet-propelled aircraft - Google Patents

Abstract

787,011. Jet propelled aircraft. POWER JETS (RESEARCH & DEVELOPMENT), Ltd. Feb. 20, 1956 [March 4, 1955], No. 6432/55. Class 4. An aircraft wing comprises a trailing edge flap mounted to turn about a virtual axis below the wing and flap, and jet propulsion means discharging a propulsive jet rearwardly over the flap to leave the rear of the wing as a long thin set sheet extending along the span of the flap, which is disposed to guide the set sheet along a path following its upper surface, the forward part of which is in the form of an arc centred on the said axis. Fig. 3 shows a cross section of the trailing edge of the wing, which comprises upper and lower skins 7, 8, and an auxiliary spar 12 through which passes a gas turbine nozzle 11a inclined upwardly at 10 to 15 degrees to the horizontal. The under surface of the nozzle is shaped to conform to the upper forward surface of the flap centred on the axis 0, and there may be a gap for cooling air or a sliding seal between the flap and nozzle. Brackets 13 extend rearwardly from spar 12 and each supports an arcuate guide track 14 (see also Fig. 5) centred on the axis O. The flap 4 comprises ribs 15 to which are secured guide blocks 16 co-operating with the track 14. The jet sheet is constrained to follow the upper surface of the flap, the limits of movement of which are shown in chain lines in Fig. 3. In an alternative construction, the flap is mounted about a forward axis in bearings which are movable fore-and-aft and the rotary and linear movements of the flap are regulated so that it turns about the axis O. There may be a spanwise series of contiguous nozzles 11a, and they may discharge upstream of the flap. A small quantity of air may be discharged between the jet sheet and the flap to prevent separation. The flap may extend from wing root to wing tip, and may be internally aircooled. Specifications 758,269 and 787,012 are referred to.