GB889540A - Improvements in or relating to jet propelled aircraft - Google Patents

Abstract

889,540. Aircraft. MARKUS, H. E. July 24, 1959, No. 25571/59. Class 4. [Also in Group XXVI] A jet propelled aircraft has narrow elongated outlet slots opening immediately above and along adjustable flaps disposed at the trailing edges of the wings, at least two gas producing units, a closed duct system connecting the unit exhausts to the slots to provide lifting thrust at least during take-off, by flat jet streams, and control valves in the duct system operable to direct at will the pressure gas from each unit to any of the slots to permit symmetrical gas distribution thereto if any unit should fail. In Fig. 1, the aircraft comprises a modified delta wing 1 on a fuselage 2. Four gas turbine engines 5 with intake ducts 6 discharge through ducts 7 into a chamber 8 having various outlet ducts. Each duct 7 contains a valve 9 so that a failed engine can be isolated. Each of two ducts 13 discharges through an elongated shallow nozzle 25 over a trailing edge flap 26, to form a jet flap arrangement. Two further ducts 12 from chamber 8 discharge through narrow elongated nozzles over elevons 34 also operating on the jet flap principle. A further duct 11 discharges vertical sheets over the surfaces of the rudder 4 on a fin 3, Fig. 9. Each of two ducts 14 controlled by valves 20 leads to a duct 15 through a valve 21, the duct discharging through an elongated nozzle 31, Fig. 5, the nozzle and wing tip inclining downwardly and outwardly. A flap 32 is provided for closing off and fairing the nozzle when not in use. Duet 16 also leads, through valves 22 and 23, to slots 17, 18 in the wing upper surface, discharging rearwardly tangentially to the wing upper surface to energize the boundary layer. Each duct 14 also leads through a valve 24 to a forwardly and downwardly inclined elongated nozzle 19, located in the undersurface of the wing, for braking purposes. Nozzles 19 also have flaps for closing off and fairing the nozzles. The various valves and flaps are controlled manually or by autopilot. The downwardly inclined sheet discharges from nozzles 31 are stated to modify favourably the airflow at the tips of a low aspect ratio wing. Fig. 10a shows a modified form of a trailing edge jet flap arrangement suitable for thrust reversal. The narrow elongated nozzle 43 discharges over a flap 44 pivoted on an axis 28. The flap has pivoted parts 29, 30 which in the position shown in full lines form parts of the flap surface. In the position shown in broken lines, the exhaust gases are discharged forwardly and downwardly. A flap 27 controls the area of nozzle 43 to suit the gas supply available. In one modification of the gas supply system, two gas turbine engines discharge into a chamber normally divided in two by a flap valve, so that each engine normally communicates with the nozzles in one half of the wing. Should either engine fail, the flap valve can be moved so that the other engine supplies all the nozzles, see Fig. 10 (not shown). In this modification, the wing has a vertical fin at each extremity, each fin supporting a rudder. In another arrangement the exhaust duct from each of two engines is bifurcated, and each nozzle draws half its gas supply from each engine, see Fig. 11 (not shown). In a further arrangement, each engine is mounted in a pod supported below the wing by a pylon. In normal flight, the engine feeds a rearwardly discharging afterburner in the pod. For take-off and landing the exhaust gases of all the engines are diverted from the afterburners to a common duct system feeding wing trailing edge jet flap arrangements, see Fig. 12 (not shown). Fig. 13 shows another aircraft, in which gas turbine engines 70 feed a chamber 71 supplying ducts 72, which discharge jet sheets from any of a plurality of peripherally arranged elongated nozzles 73.