What happened
On May 25, 2017, at approximately 12:17 UTC, a Bell TAH-1F helicopter was performing a landing at the Reutte-Höfen airfield in Tyrol, Austria. The pilot, flying solo, had completed an exhibition flight and intended to land at the airfield's fuel station to refuel before returning to the home base.
To ensure the fuel hose—which the pilot knew was relatively short—could reach the aircraft, the pilot maneuvered the helicopter into a hover near the station. The pilot executed a 90-degree turn to align the aircraft parallel to the station building. Upon touchdown, the aircraft drifted slightly toward the building, a movement the pilot attributed to gusty winds, though he also noted a potential error in distance estimation.
After the skids made contact with the ground, the pilot reduced engine power to idle. As the rotor blades descended, they struck the overhang and the left wall of the fuel station building. The impact caused severe vibrations and the immediate disintegration of several components. The force of the collision destroyed the rotor blades, the rotor head, the mast, and the transmission, and even caused the tail boom and tail rotor shaft to separate from the main fuselage. Fragments of the rotor blades were thrown approximately 140 meters away. The pilot was able to shut down the engine and secure the fuel system, exiting the aircraft uninjured.
The investigation
The SUB investigation reconstructed the flight path using pilot testimony, eyewitness accounts, and police findings. The investigation examined the aircraft's maintenance history, the pilot's credentials, and the environmental conditions at the time of the accident. Investigators also reviewed the physical damage to the Bell TAH-1F and the fuel station structure.
Findings
- The pilot possessed a valid Commercial Pilot License (CPL-H) and sufficient type experience for the Bell TAH-1F.
- There were no pre-existing mechanical defects or medical impairments found in the pilot.
- The aircraft was operating under a valid experimental category for exhibition purposes.
- Weather conditions involved light turbulence with winds from approximately 20 degrees at 10 knots, with gusts up to 15 knots.
- The fuel station's hose length was 13 meters from the edge of the roof overhang.
- The primary cause of the accident was a collision with an obstacle during landing.
- A contributing factor was the pilot's misjudgment of the distance between the helicopter and the station building, compounded by the need to position the aircraft specifically to reach the fuel nozzle located on the side of the aircraft opposite the station.