Crash d'un PIK-16 C lors d'un atterrissage par vent de travers turbulent à l'aéroport de Sion
Le 4 juin 1967, un PIK-16 C a effectué un atterrissage forcé à l'aéroport de Sion en Suisse. Le pilote, de retour d'un vol d'entraînement, a rencontré des vents de travers forts et des turbulences lors de l'approche finale. Le planeur a perdu de la vitesse et s'est écrasé sur son aile droite, entraînant de graves blessures pour le pilote et la destruction de l'appareil. Le rapport officiel a conclu que l'accident était probablement dû à une perte de vitesse dans des vents de travers turbulents lors du dernier virage.
- Training flight return: After more than two hours of solo training in the local soaring areas, the pilot returned to the Sion aerodrome to land.
- Turbulent crosswind: In the circuit area the pilot encountered a significant crosswind with strong turbulence and downdrafts generated by nearby terrain.
- Low height in circuit: While flying the downwind leg in sink, the pilot lost height more rapidly than expected and found himself low in the circuit.
- High-speed downwind: Aware of turbulence and downdrafts on the downwind leg, the pilot tightened his harness and increased speed to about 140 km/h to improve penetration and control.
- Short, low final turn: To compensate for his low height, the pilot shortened the circuit and initiated the final right turn at low altitude with about 50° of bank before the last hangar.
- Stall in turbulent turn: During the end of the final turn, with a strong turbulent crosswind and tailwind component, the glider abruptly dropped onto the right wing and descended nose-first, consistent with a loss of airspeed and stall.
- Crash - serious injury: The glider struck the ground on its right wing and nose near the threshold of grass runway 26, destroying the fuselage up to the seat area and seriously injuring the pilot.