Vittorio Isacco designed and built four different Helicogyre experimental helicopters between 1926 and 1935. In 1928 Air Ministry Specification 2/28 was issued to S.E Saunders for a prototype helicopter to the Helicogyre No. 3 design.[1]
The Helicogyre had a conventional 1920s tractor aircraft fuselage and main landing gear but had an extended tailskid to keep the fuselage horizontal.[1] At the front of the fuselage was a 100 hp (75 kW) Armstrong Siddeley Genet piston engine.[1] Behind the cockpit was a braced post on which was fitted a four-bladed rotor, each rotor blade was fitted with a 32 hp (24 kW) Bristol Cherub piston engine at the tip.[1]
The Helicogyre serial numberK1171 was completed in 1929 and delivered to the Royal Aircraft Establishment at Farnborough by road.[1] It was tested in the Balloon Shed,[2] but ground tests were not completed and the programme was cancelled on 30 December 1931 without the Helicogyre having flown.[1]
