Incident du DFS Kranich à Kerenzerberg entraînant une collision avec des arbres
Le 17 mai 1964, un DFS Kranich II a été impliqué dans un incident à Kerenzerberg, Suisse. Le planeur, transportant un pilote et un passager, est entré en collision avec des cimes d'arbres lors d'un vol de crête. Le pilote a subi de légères blessures au visage, tandis que le passager est resté indemne. L'appareil a été détruit lors de l'impact. L'enquête n'a révélé aucun défaut technique, et l'incident était probablement dû à une erreur de pilotage.
- Winch launch ridge flight: The DFS Kranich HB-481 was winch-launched from Mollis for a ridge-soaring flight along the Kerenzerberg with a pilot and passenger on board.
- Limited pilot experience: The pilot had relatively low overall gliding experience and only a few hours and flights on the Kranich type, whose stall and handling characteristics were known to be not very forgiving.
- Low, close ridge flying: After release the glider climbed to about 300 m above the airfield and then flew in fairly close proximity to the Kerenzerberg slope at low height gain using figure-eight passes.
- Improper turn away: While flying near the slope at 70–80 km/h, the pilot initiated a left turn to reverse course away from the ridge but likely mis-coordinated the controls, using aileron without adequate rudder input.
- Continued circling near slope: When the glider continued turning left instead of rolling out, the pilot chose to complete a full circle toward the slope and then again attempted to roll out, still struggling to stop the left turn.
- Loss of control near terrain: Despite increased right control input and higher speed, the glider remained in a left-turning, slipping attitude toward the ridge with insufficient horizontal clearance, making collision unavoidable.
- Crash - minor injury: Around 1720 the glider struck the crowns of tall beech trees above the Kerenzerberg road, tumbled down through the forest and was destroyed, with the pilot sustaining minor facial injuries and the passenger uninjured.