Fatal Training Flight Crash into Lake Constance (HB-IRK)

Incident Overview and Occupants On 0857LT, an aircraft departed Zurich-Kloten for a local training flight. The airplane carried a total of nine occupants: one instructor, five student pilots, two engineers, and one technician. All nine individuals were killed in the accident. The flight involved different circuits at altitudes between 1,000 and 3,000 meters. Control of the aircraft was lost over Lake Constance, leading to a spin and a crash into the water approximately 4 km off Romanshorn. The wreckage sank to a depth of 200 meters, with only a small amount of debris recovered on the water surface and along the bank between Romanshorn and Arbon. ## Official Findings and Probable Cause The official investigation found no evidence of technical malfunction in the wreckage. At the time of impact with the water, the aircraft was in the following configuration: the undercarriage was fully extended, the flaps were retracted, the trim position could not be determined, and the right propeller was not feathered. The twin RPM indicator showed the left engine at 1,550 RPM and the right engine at 1,350 RPM. The accident was attributed to the stalling of the aircraft following a loss of airspeed, which caused it to unintentionally enter a spin. Due to insufficient altitude, it was not possible to level off the aircraft.