John N. Dennis 1921-xxxx

L-R Ron Gellatly, John Dennis and David Masters

Fairy Gyrodyne

Fairey Aviation at WhiteWaltham test pilot signatures Gordon Slade,Peter Twiss,Roy Morris and John Dennis

John Dennis joined the R.A.F.V.R. in 1938 and served with Nos. 3 and 139 Squadrons.  In 1942 he joined the Autogiro Squadron at Halton, and in 1944, after taking the No. 1 Helicopter School course at Andover, went to the Airborne Forces Experimental Establishment at Beaulieu, Hants, for rotating-wing research and  development duty.

In 1945 he was posted to R.A.E., Farnborough, as a Service Pilot, and a year later became a civil pilot there. More than 750 hours of his 3,000 hours' flying  at that time in 1949 had been on rotating-wing aircraft. On June 1^st 1949 .F/L. John Norman Dennis was appointed rotating-wing test-pilot to the Fairey Aviation Company's Rotorcraft Division.

With the Jet Gyrodyne, Faireys were first in the world to secure a complete and realistic transition cycle in flight, the feat having been achieved on March 1 1955 by John Dennis as test pilot.

The Jet Gyrodyne, as the Fairey Gyrodyne was redesignated, was the subject of a Ministry of Supply research contract. Its function was to continue testing the tip-jet principle and develop procedures for the convertible helicopter, as represented by the Rotodyne. While the Jet Gyrodyne retained the basic appearance and engine of the earlier model, it had a two-bladed main rotor with pressure burners at the tips in place of the conventional three-bladed rotor, and at the end of the stub wings were two Fairey variable-pitch pusher propellers. These were driven by the Leonides engine which no longer drove the main rotor; instead, two Rolls-Royce Merlin compressors pumped air under pressure to the rotor tips.

Tethered flights at White Waltham were followed by the first free flight in January 1954, but a full transition to horizontal from vertical flight was not achieved until March 1955. System proving continued and by September 1956, 190 transitions and 140 autorotative landings had been made.