Incidente del Grunau Baby en el aeródromo de Birrfeld: colisión con un terraplén durante el aterrizaje

El 11 de abril de 1967, un Edmund Schneider Grunau Baby II experimentó un incidente de aterrizaje en el aeródromo de Birrfeld, Suiza. El piloto intentó aterrizar después de un vuelo corto pero calculó mal la altitud. El ala izquierda del planeador chocó contra un terraplén de 2,5 metros de altura, causando que la aeronave girara 180 grados y sufriera daños significativos al contactar con el suelo. El piloto sufrió una lesión por compresión de una vértebra lumbar. La investigación destacó la inexperiencia del piloto y la dificultad para estimar la altitud como factores contribuyentes.

1. Aerotow local flight: The pilot aerotowed from Birrfeld to the Holderbank/Schinznach-Bad area for a local soaring flight of about 10 minutes.
2. Altimeter malfunction: Shortly after takeoff the pilot noticed the altimeter was not indicating correctly, forcing him to estimate his altitude for the remainder of the flight.
3. Low experience and recency: The pilot had only about 21 hours total gliding experience, roughly 3 hours since his license, and had not flown for more than three months prior to this flight.
4. Misjudged height for circuit: On returning to Birrfeld, the pilot incorrectly assessed that his height was sufficient to fly a half circuit and integrate into the landing pattern for runway 26 instead of planning an immediate outlanding.
5. Flies low base-to-final: He flew the downwind leg along the 600 m runway and then, about 100 m east of it, initiated a 180° left turn toward final approach at an insufficient height above ground.
6. Left wing strikes earth bank: During the low-altitude left turn, the glider’s left wingtip struck a 2.5 m high earth bank located along the extension of the southern runway boundary, causing the aircraft to yaw almost 180° and touch down in a strong sideslip.
7. Crash - minor injury: The glider landed hard outside the airfield boundary, sustaining substantial damage, and the pilot suffered a lumbar vertebral compression injury.