What happened
On September 4, 1977, a Morane Saul andnier MS 894 A, registration HB-ETTM, was conducting a commercial VFR sightseeing flight at the Hasenstrick aerodrome. The aircraft, carrying the pilot and three passengers, departed from runway 11 at 13:56 local time. During the approach to runway 29, the pilot encountered a light tailwind and found the aircraft too high, leading to a missed approach.
On the subsequent attempt, the pilot approached at approximately 115 km/h. The aircraft touched down roughly 20 meters past the runway threshold. The pilot did not immediately apply heavy braking. Upon realizing the remaining runway length was insufficient, full braking was applied; however, the wheels locked on the wet surface during the final 15 meters of the runway. The aircraft subsequently overran the end of the grass strip and rolled down an embankment toward a nearby road, causing substantial damage to the engine, propeller, landing gear, and wing.
All four occupants remained uninjured.
The investigation
Investigators examined the pilot's credentials, the aircraft's maintenance history, and the environmental conditions at the time of the accident. The pilot held a valid commercial pilot license with limited privileges and had performed 24 previous sightseeing flights at this location, though his experience with the specific accident pattern was low. The aircraft had undergone a recent 100-hour inspection and a state inspection in August 1977, with no mechanical defects found.
Environmental factors included a wet runway surface following recent rainfall and variable winds. The investigation also reviewed the aerodrome's operating regulations, noting that the airfield is restricted to members of the Hasenstrick flight group and requires specific training regarding its unique characteristics, such as its longitudinal gradient.
Findings
- The primary cause was an inappropriate landing technique under challenging conditions.
- The pilot's experience with the specific accident pattern and the aerodrome's particular characteristics was insufficient.
- The initial airfield orientation/instruction provided to the pilot was inadequate.
- The presence of a tailwind and a wet runway significantly increased the required landing roll, which was not adequately managed by the pilot's delayed braking response.