Event Overview
On 6 July 2013, at approximately 10:38 local time, a Robinson R22 Beta helicopter, registration HB-ZDI, was involved in an accident during a training flight at Vorder Huebäbni, in the municipality of Altishofen, Canton Lucerne, Switzerland. The accident occurred about 20 km west of Luzern-Beromünster airfield. The helicopter was operated by Airport Helicopter AHB AG of Neudorf.
Flight Crew and Student
The flight instructor was a Swiss citizen born in 1969, holding a commercial pilot licence (CPL(H)) and a flight instructor rating (FI(H)) for the R22. He had accumulated 1,214 total flight hours, including 711 hours on the accident helicopter type, 407 hours as an instructor, and 356 hours on introductory flights. The student, a Swiss citizen born in 1930, had previously held a fixed-wing pilot licence and had completed four helicopter introductory flights, some in the Robinson R22. He informed the instructor that he wished to practice hovering, as his previous attempts had been unsuccessful. The student also mentioned that he wore hearing aids, which occasionally caused communication difficulties with headsets.
Flight Sequence
The flight departed Luzern-Beromünster at 10:05. The instructor initially flew while the student followed the controls. After reaching approximately 1,000 ft above ground, the instructor allowed the student to handle the cyclic control during turns. The instructor then identified a suitable meadow for hover exercises and landed there at 10:20.
Hovering exercises began at about 1 meter above ground. The instructor had the student practice each control individually: first the pedals (yaw), then the cyclic (attitude), and then the collective (altitude). According to the student, he believed he was eventually given control of all three controls simultaneously, though the instructor stated he never released full control. During the third hover exercise, after about one minute, the student made an abrupt cyclic input to the right, then to the left. The instructor called "my controls" and attempted to take over, but found the student's hands clenched on the cyclic, preventing override. The helicopter began drifting left, contacted the ground, and tipped over onto its left skid—a dynamic rollover. The main rotor blades struck the ground, substantially damaging the helicopter. The instructor exited through the shattered windshield and assisted the student out.
Injuries and Damage
The student sustained a laceration and contusion on the back of his head, and the instructor sustained abrasions and contusions. Both were classified as minor injuries. The helicopter was substantially damaged. No third-party damage occurred.
Contributing Factors
The accident was characterized as a dynamic rollover, a phenomenon where a helicopter tips over a skid or wheel when lateral drift occurs during hover or takeoff, and the main rotor thrust accelerates the roll beyond a critical angle.
Meteorological Conditions
The general weather was influenced by a high-pressure system with its core over the region, but no further details were recorded.