A system for controlling flow through a passageway located in the aft 30 percent chord region of an aircraft wing airfoil to change the aerodynamic flow pattern during ground roll conditions, and thereby spoil lift, generate a downwardly acting force to increase the effective aircraft weight on the wheels, increase drag, and create thrust reversal by redirection of engine exhaust gases. The preferred embodiments involve unique flap means which may be actuated into position to intercept flow beneath the wing and turn the flow upwardly through the passageway. Disclosed flap members include a modified Fowler flap with provision for increased rotation forwardly to an acute angle with respect to the wing, and several optional cascade vane flap devices. An improved spoiler member incorporating an aft facing convex surface is also presented.
Novel means for deploying airplane wing flaps feature a bent shaft which is translatable fore and aft in the fairing cavity. The shaft has an adjacent follower member which travels in a concentric curved flap track to rotate shaft as it extends. The bent shaft has a support ball fitting and end roller which provide flap deflection with respect to the fixed wing as the shaft is extended aft and rotated. The subject flap deployment means are mechanically elegant resulting in lower manufacturing and installation cost and high reliability.
A turbine blade having an extensible tail is described. The extensible tail is selectively positionable during engine operation, enabling fine-tuning for maximum power and efficiency during engine operation. During periods of operation exhibiting low Reynolds number flows, the extensible tail is projected out from the trailing edge of the turbine blade, into the gas path. As Reynolds number flows increase, the extensible tail is retracted back into the turbine blade, maximizing turbine engine efficiency.
A short take off and vertical landing (STOVL) nozzle for a jet aircraft provides thrust reversing and thrust vectoring functions using two pairs of flaps. Each flap is independently actuated and controlled to allow for numerous exhaust gas exit configurations. A two dimensional or rectangular center plug extends across the nozzle throat region to allow one pair of flaps to selectively engage the plug for STOVL operation.
A compound helicopter shown in FIG. 1 of the drawings has wings 12 in addition to a helicopter rotor 14 and has twin powerplants 16 each including a low pressure compressor 18, a core engine 20, a power turbine 22 driven by the core engine and connected through a gearbox 32 to drive the helicopter rotor, and a variable area final, propulsion nozzle 24 which receives the exhaust from the power turbine. Augmentor wing flaps 28 are provided on the wings and fed with air from the low pressure compressor for providing additional lift and thrust from the wings. In operation, at take-off the nozzles 24 are fully opened and all of the power produced by the power turbines 22 is used in driving the helicopter rotor for producing lift. In addition, the augmentor wing flaps 28 are directed downwardly to provide lift. For forward flight the nozzles 24 are closed down, reducing the power to the rotor and slowing it down, while at the same time generating forward thrust. Additional forward thrust is derived from the flow of compressed air through the augmentor wing flaps 28.
A compound helicopter shown in FIG. 1 of the drawings has wings 12 in addition to a helicopter rotor 14 and has twin powerplants 16 each including a low pressure compressor 18, a gas generator 20, a power turbine 22 driven by the gas generator and connected through a gearbox 32 to drive the helicopter rotor, and a variable area final propulsion nozzle 24 which receives the exhaust from the power turbine. Augmentor wing flaps 28 are provided on the wings and fed with air from the low pressure compressor for providing additional lift and thrust from the wings. The flaps 28 are pivotally mounted on the trailing edge of the wing and are movable to a position where the trailing edges of the flaps 28 obturate the flow through the gap between the flaps 28. In this position the flaps provide a means of decelerating the forward speed of the aircraft.
