Incident d'atterrissage en campagne du L-Spatz 55 près de Lostorf entraîne de lourds dommages à l'appareil

Le 4 août 1971, un Scheibe-Flugzeugbau GmbH L-Spatz 55 a effectué un atterrissage en campagne près de Lostorf, en Suisse. Le pilote, parti de Courtelary, avait l'intention de rejoindre Birrfeld mais a choisi de se poser à Olten en raison d'une altitude insuffisante. Incapable de localiser l'aérodrome, il a continué vers Lostorf, choisissant un plateau en pente pour l'atterrissage. Lors de l'approche, le planeur a survolé la zone d'atterrissage prévue et a percuté un champ de maïs. Le pilote est resté indemne, mais l'appareil a subi des dommages importants.

1. Aerotow cross-country: The pilot launched by aerotow from Courtelary for a cross-country flight toward Birrfeld and released at about 800 m above ground.
2. Low cruising altitude: En route the pilot only reached about 700 m above ground near Olten, leaving limited height margin for continuing the cross-country flight.
3. Outlanding field selected: Unable to locate the Olten airfield, the pilot continued to Lostorf and chose a slightly elevated, sloping plateau south of the town as an outlanding field.
4. Downslope and tailwind: The chosen field sloped downhill in the intended landing direction and the pilot later determined he was landing with a light tailwind.
5. Complex downslope approach: To reach the field the pilot flew a right turn with increased speed over a high-voltage line, then performed a slipping approach with full airbrakes over a preceding wood.
6. Speed control lost: During the slip the pilot lost control of airspeed, and when he levelled in ground effect he noticed the glider had accelerated to about 100 km/h and was overshooting the sloping field.
7. Outlanding - damage: After retracting the airbrakes and pulling up at the end of the field, the glider’s tail struck 1.3 m high maize plants and then impacted the adjacent field, heavily damaging the aircraft but leaving the pilot uninjured.