Slingsby T.34 Sky
The Sky first flew in prototype form in September 1950 and was designed for the 1951 British National Championships, in which it came first and second, at the request of the newly-formed Royal Air Force Gliding and Soaring Association, who wanted a contest sailplane with a better performance than that of the well-known DFS Weihe. The Sky was basically an 18m span version of the 15m Slingsby Gull 4 with a longer fuselage and was at first known as the Gull 5 or the 'Slingsby 18 metre', but the name Sky was suggested by John Furlong as it was made up of the initial letters of Slingsby, Kirbymoorside where the firm's works were, and Yorkshire. The Gull 4 was intended to be Slingsby's postwar 15m design, but did not go into production as the rival EoN Olympia was cheaper. The Sky, which resembled it, was of conventional wood and fabric construction; the production aircraft were designated T34A Sky 1 to distinguish them from the improved T34B Sky 2 intended for the 1954 World Championships but not, in the end, built. This version had NACA 64-/63 series wing sections instead of the Mk 1 's Gottingen 547 and NACA 2R 12 aerofoils, and revised squarecut wing wips and tail units. The high single-spar cantilever wings have a leading edge torsion box and a light secondary spar to carry the two-piece ailerons; the wing is fabriccovered aft of the main spar and DFS-type air brakes are fitted in the upper surfaces, but there are no flaps. The fuselage is a ply-covered stressed skin wooden structure, and the landing gear is a single fixed monowheel behind an ash skid under the forward fuselage; there is a tail bumper and a jettisonable two-wheel dolly can be used in place of the monowheel. The tailplane is cantilever and the rudder and elevators are fabric-covered. The pilot sits under a one-piece moulded Perspex canopy and has adjustable rudder pedals; oxygen, radio and barographs can be installed for contest flying.
Although only 16 examples were built, the Sky high performance single-seater has a secure place in gliding history as being the first British-designed type to win the World Championships, which it did in 1952 flown by Philip Wills when this event was held at Cuatro Vientos, near Madrid; eight T34 Skys took part, also being flown by the Dutch and Argentine teams, and all but one of them were placed in the first 14, including the 3rd place taken by Robert Forbes. Philip Wills flew his Sky into second place in the 1954 World Championships at Camphill, Bedfordshire, and in the 1956 event this place was taken by Luis Vicente Juez of Spain in another Sky.
Span: 59 ft 0.5 in
Length: 25 ft 1.25 in
Wing area: 187 sqft
Aspect ratio: 18.7
Empty weight: 556 lb
Max weight: 800 lb
Max speed: 113 mph
Min sinking speed: 2.17ft/sec at 39mph
Best glide ratio: 27.5:1 at 43 mph