What happened
On July 21, 1973, a Piper J3C, registration HB-OCF, departed from the Hasenstrick airfield for a flight following a stop in Wangen-Lachen. During the takeoff roll on runway 11, the aircraft drifted from the centerline toward the right. The aircraft encountered soft, recently replenished ground and thick grass, which significantly impeded its progress. Instead of aborting the takeoff, the pilot attempted to lift the tail to regain control. Consequently, the aircraft became airborne with insufficient airspeed, failed to clear the terrain, and struck a wooden utility pole at an altitude of approximately 4 meters. The impact tore the right wing from the aircraft, causing it to crash. The pilot sustained fatal injuries, while the passenger suffered serious injuries. The aircraft was destroyed.
The investigation
The investigation examined the pilot's actions, the aircraft's condition, and the environmental factors at the airfield. Investigators found that the aircraft was overloaded by 38 kg at the time of departure. The investigation also reviewed the pilot's recent activities, noting that he had consumed a significant amount of alcohol during a meal prior to the flight. Medical examinations of the pilot revealed a blood alcohol concentration of 0.64–0.65 weight percent. Furthermore, the investigation looked into the airfield conditions, noting that the runway was short due to maintenance work and that the ground to the right of the centerline was soft and uncompacted.
Findings
- The primary cause of the accident was the aircraft veering from the runway centerline and the pilot's failure to abort the takeoff in a timely manner.
- The pilot's airworthiness was significantly impaired by alcohol consumption.
- The aircraft was operating above its maximum allowable weight.
- The pilot failed to perform standard pre-flight checks or engine warm-up procedures.
- The presence of underlying cardiac conditions in the pilot may have contributed to impaired decision-making or physical impairment during the takeoff sequence.