What happened
On 05 May 2006, a Robinson R22 Beta helicopter, registration ZS-RAO, was conducting a private flight between two nearby locations in the Vaalwater area. The flight originated from Steenbokpan farm and was intended for a short trip to Umzimpele farm.
While the pilot was approaching an open field for landing at an airspeed of roughly 50 knots, the engine experienced a sudden loss of power. In an attempt to maintain forward airspeed following the power loss, the pilot lowered the collective pitch lever. However, the presence of tall trees in the landing area made it impossible to maintain sufficient clearance. The aircraft subsequently struck the trees, causing the helicopter to roll onto its port side. While the pilot escaped without injury, the passenger sustained a wrist injury.
The investigation
SACAA AIID investigators examined the wreckage and the circumstances surrounding the flight. The investigation confirmed that the main rotor blades sustained significant damage due to the impact with the trees, and the tail rotor blades failed during the collision.
Technical inspections of the engine were conducted at an approved maintenance organization. Following the recovery of the aircraft, ground run tests were performed, which revealed that the engine operated smoothly and showed no mechanical abnormalities. Records indicated that the aircraft's last Mandatory Periodic Inspection (MPI) had been completed on 13 March 2006, and the aircraft had flown 100.6 hours since that inspection. The maintenance organization responsible for the aircraft was also found to have been properly audited within the previous two years with no major findings noted.
Findings
- The primary cause of the accident was the collision with tall trees during the landing sequence.
- A contributing factor was an error in judgment by the pilot regarding the maintenance of safe clearance from the trees during the approach.