An aircraft having a lift/propulsion unit which includes a power unit such as a turboshaft engine which drives a fan through a transmission mechanism. The fan discharges to vectoring nozzles which can be independently swivelled to provide lift or propulsion thrust. An output shaft of the transmission mechanism serves as the main shaft of a motor/generator of modular form. The motor/generator can act as a generator to charge an electrical storage device such as a battery, or as a motor to drive the fan, either alone or to supplement the output of engine. Reaction control nozzles are provided at extremities of the aircraft to provide stabilizing thrust. The aircraft is capable of vertical take off and hovering, with the vectoring nozzles swivelled to a lift position, and forward thrust with the vectoring nozzles swivelled to a propulsion position.