Cirrus crash at Mürtschenstock after suspected stall during flight
On June 2, 1977, a Schempp-Hirth Cirrus crashed on the northwest side of Mürtschenstock, Switzerland. The pilot had departed from Schänis Airfield for a training flight and was last heard from in the early afternoon. The wreckage was discovered the following day by a military helicopter crew. The pilot did not survive, and the aircraft was destroyed. The investigation suggested that the crash likely resulted from the aircraft entering a stall, although the exact reasons remain unknown.
- Aerotow to cruise: The pilot aerotowed from Schänis at 12:28 and released near the Mattstock to continue a solo training cross-country soaring flight.
- Turbulent lee conditions: In the lee of the Mürtschenstock there were temporally and locally varying, moderately turbulent thermals that could promote inadvertent speed decay at low margins.
- Speed below minimum: For unknown reasons the glider’s airspeed dropped below the minimum safe speed while flying in the turbulent lee-side area.
- Right spin develops: The Cirrus entered a right-hand spin, consistent with an aerodynamic stall at insufficient airspeed and height.
- Spin not recovered: The pilot either initiated recovery too late or not decisively enough, and the right-hand spin was not stopped before ground impact.
- Crash - fatal: Still in a right-hand spin attitude, the glider impacted a 45° snow slope on the northwest side of the Mürtschenstock, fatally injuring the pilot and destroying the aircraft.