No fatalities

Skydiving Flight Stalls During Initial Climb in Sion (HB-FFY)

Sion, SwitzerlandTakeoff (climb)

On December 31, 1976, a Pilatus PC-6 (Porter & Turbo Porter) (registration HB-FFY) operated by Air-Glaciers was involved in an aviation accident near Sion, Switzerland during takeoff. No fatalities were reported. Investigators recorded the probable cause as: Loss of speed due to abnormal use of flight controls and landing flaps, with contributing factors including premature flap retraction, overweight conditions, passenger overcapacity, and limited pilot experience. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 2 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 2026-06-12Data APIEditorial standards

A single-engine airplane on a local skydiving flight stalled at about 100 feet after rotation, crashing back onto runway 08. One passenger sustained minor injuries, and the aircraft was written off.

Incident

A single-engine airplane conducting a local skydiving flight in the Sion area experienced a stall during its initial climb and crashed back onto the runway. The aircraft had flaps set at 28° for takeoff from runway 08. After rotation, while climbing to approximately 100 feet, the tail stalled, causing the airplane to settle back onto the runway. On impact, the undercarriage was torn off, and the aircraft came to rest a few dozen meters further.

All nine occupants were evacuated following the accident. One passenger suffered slight injuries. The aircraft was declared a total loss.

Investigation

Official investigation findings determined that the accident resulted from a loss of speed due to abnormal use of flight controls and landing flaps. Contributing factors identified include:

  • A stall during initial climb after the pilot prematurely retracted the flaps from 28° to 14°.
  • At the time of the accident, the total weight of the aircraft was 2,600 kilograms, which was 185 kilograms above the maximum takeoff weight (MTOW) for the existing flying conditions.
  • There were eight passengers on board, whereas the aircraft was certified for a maximum of seven passengers.
  • The pilot had relatively limited experience.

Probable Cause

Loss of speed due to abnormal use of flight controls and landing flaps, with contributing factors including premature flap retraction, overweight conditions, passenger overcapacity, and limited pilot experience.