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An aircraft having a fuselage, a wing, twin booms spaced from the fuselage, one on each side thereof, and a stabilizer supported by the booms, further comprises a plurality of lifting fans mounted in the booms and arranged to draw in air and to discharge it downwardly to produce lifting thrust on the aircraft. The aircraft comprises a fuselage 1, high‐mounted wing 2 and a pair of booms 3 which carry a tail unit 4, 5. A cluster of three jet‐propulsion engines 6 is mounted beneath the wing adjacent each boom and each boom houses a bank of eight direct‐lift fans located in longitudinal positions that ensure that their resulting line of lifting thrust passes through the aircraft centre of gravity. Each engine 6 comprises an auxiliary compressor independent of the engine compressor, which may be driven by an exhaust gas driven turbine forward or rearward of the main engine or the auxiliary compressor may be driven by clutches from the turbine rotor driving the main engine compressor or by gearing. The air delivered by the auxiliary compressors is fed to a common balancing duct 47 from whence it passes through ducts 48 and 49 to the inlet volute 16 of each lifting fan 7 to drive a turbine 13 associated with fan blades 12. Stator blades 14 and 17 are provided and any set of blades may be angularly adjustable and the fan inlet nozzle may be of variable area. Adjustable shutters 19, 22 are provided at each fan inlet and outlet orifice respectively and the duct from each engine 6 incorporates a control valve and a non‐return valve so that when the fans are inoperative with shutters 19, 22 closed the compressed air from the auxiliary compressor may be directed to a supplementary propulsive jet. Differential adjustment of the fan blades, intake area or closure shutters may be used to give a lateral or pitching control effect. Specification 811,840 is referred to.