History of the Flight
The instructor, accompanied by a student pilot, departed from the parking area of Mulhouse-Habsheim aerodrome for a 30-minute air experience flight in dual control. After taking off, the instructor flew forward to runway 16 and landed the helicopter. He then gradually handed over the controls to the student pilot. During a hover flight exercise, while the student pilot was holding only the cyclic pitch stick, control of the helicopter was lost. The instructor was unable to regain control, and the helicopter struck the ground and turned over onto its left side.
Wreckage Examination
Examination of the wreckage revealed that the helicopter impacted the ground in a slightly nose-down attitude with a 90° left roll. Multiple flight control failures occurred, all as a result of the impact. The engine was found to be in operating condition.
Instructor Information
The 50-year-old instructor held a valid Commercial Pilot Licence - Helicopters (CPL(H)) and an instructor rating. He had logged 889 flight hours, of which 725 were on type, and 104 hours in the three months preceding the accident.
Meteorological Conditions
The instructor estimated the meteorological conditions at the site as calm wind and CAVOK.
Organizational and Regulatory Context
The flight was offered as an air experience flight through a gift pack. Regulatory analysis indicated that introductory flights may not be advertised for a fee or canvassed, and that air experience flights are not defined in regulations. Flights where a person takes the controls are instruction flights and must follow an approved training programme. The operator, Héli Rhin, had a declared training organisation certificate converted to an approved training organisation certificate in May 2017. The first module of the practical training for the private pilot licence includes familiarisation and flight exercises. An audit to validate compliance of the training manual was planned for September 2017 but had not yet occurred.
Statements
The instructor reported that before the flight, he conducted a pre-flight check and gave the student pilot a brief introduction. During the flight, the student performed multiple exercises with the instructor retaining control of certain controls. On the third attempt of a hover exercise where the student held only the cyclic pitch stick, the helicopter suddenly shifted left in a downward path. The instructor twice told the student to release the controls, but he believed the student did not, preventing recovery.
Conclusions
The scenario suggests that the student pilot probably over-operated the cyclic stick, causing the helicopter to shift left and descend. The instructor could not regain control. Contributing factors included the limited flight duration, which did not allow the instructor to ensure the student's dexterity, and the student's stress from an unfamiliar situation, leading to a tightened grip on the controls.