Fatal Fairchild Hiller FH 1100 Helicopter Crash Near Mönchgrün

Incident Overview and Flight Details On May 23, 2010, a Fairchild Hiller FH 1100 helicopter crashed near Mönchgrün, Germany, resulting in the deaths of the pilot and three passengers. The pilot had departed from a private heliport in Moßbach for a series of sightseeing flights. The accident occurred during the third flight at approximately 16:30 local time. Witnesses reported that the helicopter was flying at a low altitude from the direction of Möschlitz when a change in engine noise was heard. The aircraft then veered toward a wooded area west of Mönchgrün and fell vertically before impacting the ground. ## Aircraft and Maintenance History The crashed helicopter was a 1968 Fairchild Hiller FH 1100, a five-seat turbine-powered aircraft with a two-blade main rotor and a tail rotor. The aircraft had a total airframe time of approximately 2,588 hours. It was registered in the United States, although the pilot had purchased it in October 2009. The seller, an American citizen residing in Germany, remained the registered owner. In 2003, the aircraft was found to be unairworthy due to missing maintenance records and overdue components. The pilot had been introduced to the aircraft by a flight instructor, and the three flights on the day of the accident were his first without an instructor. ## Fuel and Technical Findings The investigation revealed that the helicopter was fueled with diesel fuel from canisters during the pilot's training flights. Although the fuel gauge functioned normally, the aircraft's flight manual on board was for a different registration and serial number. The manual did not specify the expected fuel consumption. According to the current type certificate holder and an NTSB report, the fuel consumption was estimated at approximately 83 liters per hour. On the day before the accident, the pilot purchased 601.38 liters of diesel fuel. At the crash site, there was no smell of fuel, and less than two liters of liquid were recovered from the fuel bladder. The engine's fuel filter contained brown contamination, and the fuel injector was heavily soiled. ## Investigation and Cause The German Federal Bureau of Aircraft Accident Investigation (BFU) conducted the investigation. The pilot held a private pilot license for helicopters and had approximately 100 hours of helicopter experience, including 12 hours on the FH 1100. The pilot's medical examination showed no health impairments during the flight, and toxicology tests were negative for drugs and carbon monoxide. The accident was deemed unsurvivable due to the high impact energy. The source text is cut off before the final probable cause is stated, but the investigation focused on fuel contamination and maintenance issues.