Slingsby T.21

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Slingsby T.21
Slingsby T.21B
Type: Practice glider
Design country:

United KingdomUnited Kingdom United Kingdom

Manufacturer:

Slingsby Sailplanes Ltd.

First flight:

December 1947

Production time:

1948-

Number of pieces:

92 (T.21 total)

The Slingsby T.21 is a training glider from the British manufacturer Slingsby Sailplanes Ltd., which was developed in the late 1940s.

history

After the end of the war, the British Air Training Command had a need for two-seat training aircraft. The same was true of the numerous British aviation clubs. Slingsby developed two training planes - in one version the student pilot and the flight instructor sat next to each other (T.21), in the other version the seats were arranged one behind the other (T.31). According to the manufacturer, a total of 92 T.21s were produced. The variant T.21B was nicknamed Sedbergh, after the town of the same name in the Yorkshire Dales National Park. The aircraft was used for training with the Air Cadets, Army Cadets and Sea Cadets (Royal Navy) as a basic training model.

There were also some civilian versions that flew in the English gliding clubs in the 1950s and 60s. But the Slingsby T.21B was also used in the overseas colonies. Kenya , Southern Rhodesia and India are particularly worthy of mention, but a station is also known from Cyprus .

After the British military decommissioned the T.21B and replaced it with training planes of the Grob G 103 type , civil clubs and private individuals took over these vintage gliders. So some came to Germany, but they fly under English registration, as the Slingsby T.21B was not previously approved in Germany and therefore no German type certification exists. According to the European rules of EASA , the Sedbergh belongs to the Annex II aircraft and is therefore only subject to national rules.

Owners of the T.21B are usually organized in the VGC Vintage Glider Club .

construction

Slingsby T.21B: cockpit with pilot seats arranged side by side

The T.21B is designed as a two-seater high-decker and has two seats next to each other. The single-spar wing is constructed in two parts, has spoilers, has a torsionally rigid box nose and is supported against the fuselage with a strut. Behind the spar, the wing is covered with fabric.

The front part of the fuselage is made up of ribs and straps with load-bearing plywood paneling. From the main rib the rear part of the fuselage is covered with fabric. At the front of the fuselage tip is a tube that can hold ballast weight in the case of single-seat flight operations.

variants

T.21B Sedbergh Mk. 1
The two seats next to each other only have one windbreak.
T.21B Sedbergh Mk. 2
A further development of the Mk. 1, which has a closed driver's seat and does not require a fuselage pylon for setting up the wing. The wing is mounted directly on a central part attached to the fuselage. This increases the span to 17.37 m. The spoilers were replaced by dive brakes.

Technical specifications

Parameter Data
crew 1 + 1
length 8.16 m
span 16.46 m
Wing extension 11.2
Wing area 24.20 m²
Wing loading 19.6 kg / m²
Wing profile inside: Göttingen 535,
outside: symmetrical
Glide ratio 21 at 60 km / h
Slightest sinking 0.85 m / s at 55 km / h
Empty mass 254 kg
Takeoff mass 454 kg
Minimum speed 45 km / h
Top speed 170 km / h

See also

literature

  • Karlheinz Kens: types of aircraft. International aviation type book. Motor planes, fixed wing planes, rotary wing planes, VTOL convertible planes, motor gliders, gliders, piston engines, jet turbines, rocket motors. 4th edition. Carl Lange Verlag, Duisburg 1963.

Web links

Individual evidence

  1. ^ Website of the Vintage Glider Club