P.74 rotor blade aerofoil tests were carried out on a Sikorsky R-4B, converted to drive a whirling arm on which the test sections were mounted.

The P.74 was never fully completed. This photograph of the helicopter, tethered at Luton Airport and sans tail rotor, was as near as it ever came to completion.

The P.74 under construction at Luton in 1955.

View of the P.74's cabin. Each seat position was provided with a large window. In the event seats were never fitted.

The partially completed P.74 undergoing initial engine tests at Luton in December 1955. The two Oryx engines were located in the helicopter's belly and were accessible through large detachable panels on each side.

Detail of one of the four torsionally-sprung undercarriage legs, the front pair of which were steerable.

Cockpit detail of the P.74.

The passenger cabin was fitted with a mass of instrumentation for test purposes.

Model of the original P.74 design, showing the large fin with an inclined-hinged rudder, later replaced by a tail rotor.

Hunting Percival P.74 helicopter