What happened
On August 26, 2024, at approximately 08:05 UTC, a Beechcraft 58TC Baron crashed into the western slope of the Mottakopf in the municipality of Brand, Vorarlberg. The aircraft had departed from Riviera Airport (LIMG) in Italy, bound for Straubing (EDMS) in Germany, operating under Instrument Flight Rules (IFR).
During the flight, the pilot requested permission to climb to higher altitudes, eventually reaching 24,500 ft. Shortly before the accident, at 07:59 UTC, the pilot contacted air traffic control with a specific request: “Request lower to avoid oxygen problems.” After being cleared to descend to 25,000 ft, the aircraft began a descent characterized by oscillating bank angles.
By 08:03 UTC, the aircraft entered a high-speed spiral dive. The descent rate accelerated to approximately 14,300 ft/min, with ground speeds reaching 332 knots. The aerodynamic loads during this dive caused a structural failure, resulting in the separation of both wings and the loss of the vertical and horizontal stabilizers. The remaining fuselage struck the terrain at approximately 1,650 m altitude and caught fire. The pilot was the sole fatality.
The investigation
The investigation by the Austrian SUB focused on reconstructing the flight path using air traffic control records, eyewitness accounts, and radar data. Investigators examined the aircraft's technical condition, including the maintenance history and the functionality of the oxygen system. The investigation also analyzed the physiological effects of high-altitude flight, specifically the risks of hypobaric hypoxia and the Time of Useful Consciousness (TUC) at the altitudes maintained during the flight.