Abstract: A helicopter aircraft with an upper hollow center circular plenum in gaseous communication with a plurality of hollow hinged attached rotor blades. Below the plenum and in gaseous communication with it are two fan jet engines whose gaseous output can be inputted to the plenum and their attached hollow rotor blades through a operator controlled valve system. This same valve system can be adjusted to completely or partially by-pass the plenum and discharge the jet engines' gas to a common rear rudder located on the aircraft's to provide directional control to the aircraft when in flight. The plenum is shaped lenticular in cross section similar to an airplane wing to provide a lifting body when the helicopter is in forward flight.

Abstract: A nozzle for use on opposing ends of the rotor of a jet powered tri-mode aircraft is disclosed. The nozzle includes two thermally-controlled doors, which are moveable between an open configuration where hot jet engine exhaust is vented therethrough to propel the rotor in a helicopter mode, and a second closed configuration where the two doors are tightly sealed to provide a stable aerodynamic surface for the rotor when the jet powered tri-mode aircraft is operating in an airplane mode. The two doors are thermally-activated by an internal surrounding temperature, such that they remain open by the hot jet engine exhaust passing thereby in the helicopter mode, and remain shut by resulting cooler air when the hot jet engine exhaust is not routed by the two nozzle doors.

Abstract: A helicopter rotor seal for gas-driven helicopters wherein the rotor is rotatably driven by a compressed air jets at the tips of the rotors directed rearwardly with respect to rotor rotation. A non-rotatable mast extends vertically from the helicopter fuselage including a concentric bore for communication of compressed air therethrough. Positioned at the upper extremity of the mast, above the rotor blades, is a rotatable plenum for distributing compressed gas to the helicopter's respective rotor blades.

Abstract: The present invention relates to a circulation flow control rotor system for an aircraft which includes rotor blades provided with slit shaped blower nozzles further comprising control devices for obtaining a cyclic or multicyclic or collective rotor blade angle control under utilization of individual pressure gas flow from a pressure chamber to the nozzle slits; further including deformable control members which are going to be deformed in accordance with certain rules underlying the requisite control.

Abstract: A plenum for a circulation control rotor aircraft which surrounds the rotor drive shaft (18) and is so constructed that the top (32), outer (38) and bottom (36) walls through compressed air is admitted are fixed to aircraft structure and the inner wall (34) through which air passes to rotor blades (14) rotates with the drive shaft and rotor blades.

Abstract: A helicopter rotor hub for use in an air-driven helicopter comprises a section of a spherical stainless steel ball attached to the end of a hollow rotor shaft. An air compressor within the helicopter supplies air to the hollow rotor shaft which discharges through it to hollow rotor blades which have discharge nozzles at the trailing edges on their tips. The sole support bearing for the blades is in the form of a cup-shaped concave graphite bearing which engages the stainless steel ball and to which the rotor blades are attached. The graphite provides a lubrication-free bearing surface and also provides a seal against air leakage.

Abstract: A rotary wing aircraft is disclosed and includes a fuselage, a gas turbine engine operated air compressor within the fuselage, and a jet nozzle driven rotor assembly situated over the fuselage and having a rotor axis about which the assembly rotates. The rotor assembly includes a generally hollow rotor hub and a plurality of generally hollow jet nozzle driven rotor blades extending radially outwardly of the rotor hub. The rotor hub defines air conduit means to the rotor blades. A section of at least one rotor blade comprises a foldable flexible air conduit for folding the rotor blade in a radial plane relative to the rotor hub. Releasable stabilizing means, including a droop stop, is disposed between the rotor hub and an outboard portion of the rotor blade beyond the flexible air conduit section, whereby the stabilizing means may be released and the blade folded in its radial plane with the flexible air conduit section acting as a hinge.

Abstract: An air jet helicopter rotor and air distribution system of the semi-rigid type, having tension straps, in which the hub is connected to a rotatable mast shaft by a teetering hinge; the mast shaft is supported by a thrust bearing; and the rotors, the hub and an upper rotatable plenum chamber which surrounds the mast shaft and from which compressed air is distributed to each rotor through flexible ducts all rotate with the mast shaft. Below and adjoining the rotatable plenum chamber and also surrounding the mast shaft is a stationary plenum chamber which is mounted atop the thrust bearing housing and which transports compressed air from a source within the helicopter into the rotatable plenum chamber. Self-centering, self-aligning air seals at the adjoinments of the plenum chambers and the stationary plenum chamber and the mast shaft allow for flexing throughout the system as well as the usual flapping and rocking movements of the rotor blades.

Abstract: Structure for minimizing gap changes in a circulation control pneumatic ve. A flat, flexible ring is located below and adjacent to the plane of the nozzle of blade ducts. The flat, flexible ring is supported from beneath by an array of actuators. In one embodiment, the nozzles are immobilized relative to hub-induced displacements and thus eliminate any feedback due to hub flexing. In another embodiment, the nozzle is pivotally attached to a rotating carrier and feedback is reversed so that feedback becomes negative.

Abstract: Aircraft engine exhaust is mixed with air and fuel and recombusted. Air is drawn into the secondary combustion chamber from suction surfaces on wings. Exhaust of the secondary combustion chamber is blown over wing and fuselage surfaces.

Abstract: A rotor hub for a helicopter having a hum member rotatably mounted to a rr mast stationarily attached to the fuselage of a helicopter and forming an air plenum for circulation control. A shaft, which is driven from a transmission, drives a torque plate which is attached to the top of the hub member. A flexible hub plate is attached to a flange on the hub member and has a plurality of axles to which the rotor blades are individually attached. Air from inside the plenum is piped to the rotor blades through flexible ducts. The flexible hub plate is designed to provide a high degree of stiffness in the plane of rotation and a lesser degree of stiffness in a plane normal to the plane of rotation.