What happened
On January 2, 2013, a Robinson R-22 Beta II helicopter, registered OO-XXX (implied Belgian registration context), was conducting a local flight training mission at EBHN airfield. The flight, which included a student pilot and an instructor, had transitioned from Antwerp airport to Hoevenen for the purpose of practicing low-level maneuvers and set-downs.
While performing a hover taxi toward the hangars, the aircraft began to deviate to the right. In an attempt to correct this deviation, the student applied left cyclic input. This maneuver caused the helicopter to lose altitude, leading the rear of the left-hand skid to strike the ground. Although the instructor attempted to correct the movement by applying right cyclic, the momentum resulted in a dynamic rollover, causing the aircraft to land on its left side. Both occupants sustained minor injuries.
The investigation
The investigation examined the aircraft's flight history, the pilot's experience, and on-board video footage. The Robinson R-22 Beta II had a total flight time of approximately 2,054 hours. The student pilot had very limited experience, with only about 12 hours of total flight time.
Investigators analyzed the mechanics of the rollover, confirming that three essential conditions for a dynamic rollover were present: sufficient main rotor thrust, ground contact/restraint, and a roll rate about the contact point. On-board video footage captured the sequence of the nose deviating, the skid making contact with the earth, and the subsequent roll. The inspection of the wreckage revealed significant damage, including a broken main rotor blade, deformed tail boom and vertical firewall, and damage to the engine power transmission belts and yoke components.
Findings
The primary cause of the accident was inadequate lateral cyclic input while the helicopter was operating at a low altitude.
Contributing factors included:
- The student pilot's lack of proficiency in mastering flight controls during low-level operations.
- The instructor's delayed reaction in intervening to correct the improper control inputs.