What happened
On September 8, 1976, a Scheibe SF-28A motor glider, registration D-KACW, crashed into a densely forested mountainside in the Valle di Campo, near Cimalmotto, Switzerland. The flight originated from Ascona with a planned route toward Samedan, but the aircraft deviated from its intended path.
After a refueling stop in Ascona, the pilot departed for a return flight to Samedan. Approximately 20 minutes into the flight, witnesses observed the aircraft flying at an alarmingly low altitude through the valley. Shortly thereafter, an observer noticed the aircraft striking trees and plunging into a steep, wooded slope on the right bank of the Rovanabach stream. The impact destroyed the aircraft and resulted in one fatality (the pilot) and one serious injury (the passenger).
The investigation
Investigators examined the wreckage and recovered aeronautical charts used during the flight. The examination of the charts revealed discrepancies between the filed flight plan and the actual path taken. While the filed plan indicated a route via Nufenen and Zermatt, the aircraft's trajectory suggested it entered the Valle di Campo, a side valley of the Maggia Valley that leads to a dead end.
The investigation also reviewed the pilot's flight history. Although the pilot held a valid license and had completed a mountain flying orientation only days prior to the accident, he lacked extensive experience in complex alpine terrain. The aircraft's engine was found to be operational at the time of the crash, and no mechanical failures were identified as contributing factors.
Findings
- The aircraft entered a narrow, dead-end valley at an altitude that did not allow for a safe turnaround.
- The pilot likely overestimated the climb performance of the SF-28A, which has a limited rate of climb, especially when flying over rising terrain.
- There was a lack of sufficient mountain flying experience.
- Poor decision-making during the flight led to the deviation from the planned route and the entry into hazardous terrain.