Aircraft

Claim 2

A lifting power plant for a V/STOL aircraft, comprising a single jet lift unit having forward and rear downwardly-directed efflux discharge ducts and a downwardly-directed exhaust trunk which is bifurcated to connect with said discharge ducts, each said duct having two generally downwardly-directed nozzles disposed laterally side by side, said nozzles being symmetrically disposed about a vertical axis extending through the center of gravity of said aircraft, and each said nozzle being equipped with efflux-direction-controlling means selectively operable to deflect the efflux from its respective nozzle only in a plane substantially at right angles to the fore and aft axis of the aircraft.

Claim 3

Power plant according to claim 1, wherein each nozzle is equipped with a set of thrust-deflecting louvres turning about fore and aft pivot axes.

Claim 4

Power plant according to claim 1, wherein said efflux-direction-controlling means are operable in a first mode in which all four effluxes are deflected laterally in unison, a second mode in which the forward pair of effluxes are deflected in unison in one direction and the rear pair in unison in the opposite direction, and a third mode in which the forward effluxes are deflected in opposite directions and the rear effluxes likewise in opposite directions but oppositely to the forward effluxes.

Claim 5

Power plant according to claim 3, wherein the efflux-direction-controlling means are arranged to deflect all the effluxes by substantially equivalent amounts, whatever the mode of operation, to preserve a substantially constant total lift component.

Claim 6

In a V/STOL aircraft, a lifting power plant comprising a jet lift unit, fixed multi-branched efflux discharge ducting therefor, a forward pair of generally downwardly-directed nozzles and a rearward pair of geNerally downwardly-directed nozzles, the nozzles in each pair being laterally spaced so that all four nozzles lie substantially at the corners of a rectangle whose center is coincident with a vertical axis which passes through the center of gravity of said aircraft, said multi-branched discharge ducting connecting said two pairs of nozzles to said jet lift unit and distributing the efflux of said jet lift unit equally to all four nozzles, each said nozzle being equipped with efflux-direction-controlling means selectively operable to deflect the efflux from its respective nozzle only in a plane substantially at right angles to the fore and aft axis of the aircraft.

Claim 7

In a V/STOL aircraft, a lifting power plant comprising a jet lift unit, fixed multi-branched efflux discharge ducting therefor, a forward pair of generally downwardly-directed nozzles and a rearward pair of geNerally downwardly-directed nozzles, the nozzles in each pair being laterally spaced so that all four nozzles lie substantially at the corners of a rectangle whose center is coincident with a vertical axis which passes through the center of gravity of said aircraft, said multi-branched discharge ducting connecting said two pairs of nozzles to said jet lift unit and distributing the efflux of said jet lift unit equally to all four nozzles, each said nozzle being equipped with efflux-direction-controlling means selectively operable to deflect the efflux from its respective nozzle only in a plane substantially at right angles to the fore and aft axis of the aircraft.

Claim 8

In a V/STOL aircraft, a lifting power plant comprising a jet lift unit mounted with its axis substantially vertical, multi-branched efflux discharge ducting at the lower end of said jet lift unit, four nozzles below said jet lift unit and lying substantially at the four corners of a rectangle two sides of which rectangle are parallel to the fore and aft axis of the aircraft, said multi-branched discharge ducting connecting said four nozzles to said jet lift unit and distributing the efflux of said jet lift unit to all four nozzles, each said nozzle being equipped with efflux-direction-controlling means selectively operable to deflect the efflux from its respective nozzle only in a plane substantially at right angles to the fore and aft axis of the aircraft.

Claim 9

In a V/STOL aircraft, a lifting power plant comprising a jet lift unit mounted with its axis substantially vertical, multi-branched efflux discharge ducting at the lower end of said jet lift unit, four nozzles below said jet lift unit and lying substantially at the four corners of a rectangle two sides of which rectangle are parallel to the fore and aft axis of the aircraft, said multi-branched discharge ducting connecting said four nozzles to said jet lift unit and distributing the efflux of said jet lift unit to all four nozzles, each said nozzle being equipped with efflux-direction-controlling means selectively operable to deflect the efflux from its respective nozzle only in a plane substantially at right angles to the fore and aft axis of the aircraft.