Aterrizaje duro del ASK 21 durante entrenamiento en el aeródromo de Schänis

El 11 de octubre de 1990, un piloto estudiante que volaba un Alexander Schleicher ASK 21 en el aeródromo de Schänis en Suiza experimentó un aterrizaje duro. Este fue el tercer vuelo en solitario del piloto en el planeador. Durante la aproximación, el planeador estaba alto y fuera de curso, lo que llevó a una serie de correcciones de trayectoria. El instructor aconsejó al piloto elevarse, pero la maniobra se ejecutó con demasiada fuerza, causando que el planeador ascendiera y luego descendiera abruptamente. El piloto estudiante sufrió heridas graves, mientras que el planeador resultó ligeramente dañado.

1. Aerotow landing pattern: During the third solo flight after an aerotow in an ASK 21, the student entered the landing circuit for runway 34 with the CG 10 mm behind the aft limit.
2. Aft CG beyond limit: The glider was flown with two trim weights missing, placing the centre of gravity 10 mm aft of the allowable rear limit, making pitch control more sensitive.
3. High, offset final: The student flew a high base and final, turning into final too late and ending up about 120 m left of the runway 34 centreline.
4. Aggressive course corrections: On final at about 120 km/h, the student first corrected slightly right, then made strong right and left corrections to regain the runway centreline, remaining high and under stress.
5. Nose-down then over-pull: Shortly before the threshold the student pushed the nose down, increasing speed, then after the instructor’s radio call to 'pull' she pulled back too strongly on the stick.
6. Balloon then sink: The glider ballooned to about 7 m above ground and then sank through in a nearly level attitude with half airbrakes extended and the nose slightly down.
7. Crash - serious injury: The glider impacted near the right edge of the paved runway, causing serious injury to the student pilot and minor damage to the aircraft.