Accident de décrochage et vrille du MDM-1 Fox près d'Arbaz, Suisse
Le 3 mai 1997, un planeur MDM-1 Fox s'est écrasé près d'Arbaz, en Suisse, entraînant la mort du pilote et du passager. Le planeur, engagé dans un vol privé, a décroché et est entré en vrille à une altitude insuffisante pour une récupération. L'appareil a été détruit lors de l'impact avec un rocher et le crash subséquent sur une zone enneigée. Les conditions météorologiques comprenaient une bonne visibilité et une légère turbulence, et le planeur était légèrement au-dessus de sa limite de poids maximale.
- Aerotow local flight: The pilot and his brother departed Sion by aerotow in an MDM-1 Fox for a local training flight and released near Anzère at about 2000 m.
- Heavily loaded glider: The glider was slightly over maximum takeoff mass and had a forward center of gravity, increasing stall speed and making it nose-heavy.
- Ridge and thermal flight: The pilot flew along the slope near Anzère searching for thermals, repeatedly traversing the Combe d'Arbaz–Les Rousses area while remaining at roughly the same altitude.
- Excessive pitch-up: While flying straight and level near the Anzère–Pas-de-Maimbré cableway, the pilot likely increased pitch in an attempt to gain extra altitude, reducing airspeed toward the stall warning region.
- Abrupt stall and spin: The glider suddenly stalled in straight flight and entered a very pronounced, steep-nosed, rapidly rotating spin observed by witnesses.
- Insufficient height for recovery: The spin developed at an altitude too low to allow full recovery before ground impact.
- Crash - fatal: After 2–3 turns of spin the glider struck a large rock, rebounded onto a snow-covered ledge, and was destroyed, fatally injuring both occupants.