The Alexander Schliecher K21 is a modern composite two-seat training glider. It can be used for basic instruction as well as cross-country training and basic aerobatics. Stratford on Avon Gliding Club owns two ASK21s G-CGAG and G-CLVU.
- Crew: 1 or 2
- Length: 8.35 m
- Wingspan: 17.00 m
- Height: 1.55 m
- Wing area: 18.0 m2
- Aspect ratio: 16.06
- Wing profile: FX S02-196 / FX 60-126
- Empty weight: 360 kg
- Gross weight: 600 kg
- Maximum speed: 151 knots
- G limits: +6.5/-4 below Va
- Maximum glide ratio: 32:1
- Rate of sink: 128ft/min (solo)