Slingsby Petrel

The Slingsby T.13 Petrel was a British single-seat competition glider built by Slingsby Sailplanes just before World War II.

Development

The Slingsby Petrel was a development of the German DFS Rhonadler designed by Hans Jacobs. It was a single-seat high-performance sailplane with a span of a little under 18 metres, built of wood with a mixture of plywood and fabric covering. It had high cantilever gull wings, though the inner section dihedral was modest. They carried straight taper to fine and rounded tips and ailerons that extended over more than half the span. There were neither flaps nor airbrakes.^[1]

The fuselage had its maximum diameter near the nose, where the long, multipiece canopy blended in smoothly, ending at the wing leading edge. Behind the wings the fuselage tapered and became slender at the tail. The fin and the tailpane were both small in area; the rudder was large, aerodynamically balanced and extended down to the keel. The elevators were tapered, with a cut out for rudder movement. The undercarriage consisted of just a main skid from below the front of the cockpit glazing to mid chord plus a tail bumper.^[1]

Operational history

The Petrel prototype first flew in December 1938. This aircraft crashed at Camphill, Derbyshire in the British National Championships of July 1939, killing its pilot, the speedway rider Frank Charles. Two more were built and flew for several decades after World War II with clubs in England and Ireland.^[2] One of them was a competitor at the 1953 British National Championships, held again at Camphill, by then known as Great Hucklow, after being bowled over in transit by a Rotherham trolley-bus.^[3]

Operating Now

Only one flying model is now airworthy, and has been flown at RAF Weston-On-The-Green, by Oxford Gliding Club. Graham Saw based at Booker Gliding Club owns and flies this glider at Vintage Gliding Club meetings and has displayed at Shuttleworth.

Specifications

Data from Ellison 1971, p. 183The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde^[4]

General characteristics

• Crew: 1
• Length: 23 ft 9 in (7.25 m)
• Wingspan: 56 ft 11 in (17.34 m)
• Wing area: 180.0 sq ft (16.72 m²)
• Aspect ratio: 17.9
• Airfoil: Göttingen 535
• Empty weight: 440 lb (199.5 kg) equipped
• Max takeoff weight: 638 lb (289.5 kg)

Performance

• G limits: +6
• Maximum glide ratio: 27 at 42 mph (67.6 km/h; 36.5 kn)
• Rate of sink: 106 ft/min (0.54 m/s) minimum, at 35 mph (56.3 km/h; 30.4 kn)
• Wing loading: 3.6 lb/sq ft (17.5 kg/m²)

Notes

References

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