Kollision der Ka 8 B mit Hindernissen nahe dem Flugplatz Birrfeld während eines Trainingsflugs

Am 15. Mai 1980 startete ein Segelflugzeug vom Typ K 8 B vom Flugplatz Birrfeld zu einem lokalen Trainingsflug. Der Pilot geriet in Abwinde und Turbulenzen in der Nähe des Chestenbergs, was zu einem schnellen Höhenverlust führte. Beim Versuch, Stromleitungen zu vermeiden, traf der linke Flügel einen Baum, wodurch der Flügel abbrach und das Segelflugzeug abstürzte. Der Pilot erlitt schwere Verletzungen, und das Flugzeug wurde stark beschädigt. Der offizielle Bericht nannte unzureichende Höhe und die Nähe zum Hang als beitragende Faktoren.

1. Ridge flight return: After a local training flight, the pilot was returning by ridge flying from the Aarau area toward Birrfeld in the late afternoon.
2. Entered lee downdraft: On the south side of the Chestenberg, the glider entered the lee of the slope and rapidly lost altitude.
3. Low altitude near field: Approaching Brunegg, the glider was only about 550 m MSL, roughly 150 m above the nearby Birrfeld airfield, leaving little height margin for further soaring attempts.
4. Limited experience: The pilot had relatively low total experience and the investigation cited insufficient airmanship and poor flight tactics as contributing factors.
5. Continued ridge search: Instead of committing to an immediate landing or outlanding, the pilot turned left to follow the north side of the Chestenberg toward WNW in search of lift at very low height.
6. Turbulence and avoidance turn: Contrary to expectations the glider encountered strong turbulence and sink, and while attempting to avoid a high-voltage power line the pilot turned left toward the slope at very low altitude.
7. Crash - serious injury: The left wing struck the top of a tree, was torn off, and the glider crashed near Birrfeld, seriously injuring the pilot and heavily damaging the aircraft.