What happened
On June 28, 1975, a Piper PA-32-300 (registration HB-OMG) departed from Bern Airport for a private visual flight rules (VFR) trip to Venice. The aircraft was carrying the pilot and six passengers. During the flight, the pilot communicated with Bern Tower, noting intentions to navigate toward Fribourg and climb through a gap in the clouds to fly "on top."
At approximately 09:34 local time, the aircraft struck the eastern face of the Lauteraarhorn in the Bernese Oberland at an altitude of roughly 3,700 meters. The impact, which occurred during a left-hand turn with a significant bank angle, resulted in the deaths of all seven occupants and the total destruction of the aircraft. The wreckage remained lost for several years until it was discovered by a mountaineer in 1981, necessitating a complex recovery operation using explosives to move the debris from a steep snow couloir.
The investigation
Investigators examined the wreckage and recovered flight instruments, which revealed the aircraft was flying at full power with the mixture set to approximately one-third retarded. The altimeter indicated a much higher altitude than the impact site, suggesting the aircraft was likely operating near the cloud ceiling (estimated between 4,000 and 4,500 meters) before the descent.
Technical inspections of the Piper PA-32-300 showed no evidence of pre-existing mechanical failures in the control linkages or engine components. The aircraft was at its maximum allowable takeoff weight at the time of the accident. The investigation also considered the pilot's flight experience, which was estimated at approximately 132 hours, and the physiological effects of high-altitude flight without supplemental oxygen.
Findings
- The primary cause of the accident was an unintended loss of altitude while flying in VFR conditions near the upper limit of the cloud layer over high terrain.
- The aircraft was operating at maximum weight near its service ceiling, which severely limited its climb performance and maneuverability.
- Environmental factors, including turbulence, downdrafts, or potential icing, may have contributed to the loss of altitude.
- The pilot's limited flight experience and the potential for hypoxia due to the lack of an onboard oxygen system may have hindered the ability to manage the critical situation.