Aircraft and Crew Information
The aircraft involved was a Robinson R44 II, registration HB-ZMQ. It was owned by Heli-Züri AG and operated by Heli Sitterdorf AG. The pilot, a Swiss citizen born in 1957, held a private pilot licence for helicopters (PPL(H)). He had accumulated 217 total flight hours, with approximately 70 hours on the accident type. He had flown 0 hours in the preceding 90 days.
Accident Sequence
On 22 December 2014 at 10:30 local time (UTC+1), the pilot was preparing for a private VFR departure from Heliport West at Zurich Airport (LSZH). He increased rotor rpm and awaited takeoff clearance from the airport traffic control. During this phase, the occupants occasionally opened a door to allow air exchange and prevent windshield fogging.
After receiving takeoff clearance, the pilot transitioned to a hover. Before he could perform the usual hover checks, the pilot-side door opened. The pilot intended to briefly land again to close the door. As he momentarily released the cyclic stick, the helicopter unexpectedly and rapidly entered an unstable attitude. According to the summary report, it is probable that at this time the collective lever was not fully lowered. The main rotor struck the ground, and the helicopter tipped over sideways.
Damage
The helicopter sustained substantial damage. Additionally, the ground was contaminated, resulting in crop damage. No third persons were involved.
Injuries
The pilot and three passengers were slightly or not injured.