ASK 21 training flight accident during landing approach in Rudolstadt
On August 9, 2000, an Alexander Schleicher ASK 21 experienced a hard landing during a training flight at Rudolstadt, Germany. The flight instructor took control during the landing approach to correct the student's high altitude. A sideslip maneuver was initiated to reduce altitude, but the aircraft entered a stall at low height, resulting in a hard impact. Both occupants sustained serious injuries, and the glider was heavily damaged. The investigation confirmed that the stall occurred due to the instructor's actions during the recovery from the sideslip.
- Training landing approach: During a training flight after a winch launch, the student flew the landing approach in normal weather conditions at Rudolstadt.
- Instructor corrects approach: The instructor judged the glider to be too high on final and took over control to avoid a long landing, deciding to use a sideslip to lose height.
- Low altitude sideslip: The instructor initiated the sideslip at approximately 40–50 m height, leaving limited altitude margin for recovery.
- Sideslip recovery input: The instructor ended the sideslip at about 8–10 m height with control inputs that brought the glider into an over‑pitched, approaching-stall attitude.
- Stall at low height: As the sideslip was terminated, the glider entered an over‑stalled flight condition at very low altitude, with a noticeable loss of airspeed despite the instructor’s attempt to push the nose down.
- Crash - serious injury: The glider dropped from about 5 m, impacted the ground very hard on the main gear, bounced and then struck the ground again on the nose gear, seriously injuring both occupants and heavily damaging the ASK 21.