What happened
On 23 February 2006, a Bell 206L-3 helicopter, registration ZS-HSX, was conducting a chartered sightseeing flight departing from the V&A Waterfront in Cape Town. The flight was intended to last approximately one hour, returning to the same departure point. Shortly after takeoff, the pilot noted the aircraft felt heavy, though the helicopter successfully climbed to an altitude of 2,500ft AGL.
While flying over the Scarborough area, the pilot received an "engine out" audio alert followed by a low rotor RPM warning. The pilot immediately notified the six passengers and initiated an emergency autorotation toward a sandy beach. While the descent was described as controlled, the aircraft struck the ground with significant force. The skids dug into the soft sand, causing the helicopter to skid forward and eventually come to rest on its starboard side. The impact caused the main rotor blades to sever the tailboom and led to extensive structural damage to the fuselage. All 7 occupants sustained serious injuries.
The investigation
Investigators examined the mechanical state of the aircraft and the flight parameters during the emergency. The investigation confirmed that the aircraft had undergone its last mandatory periodic inspection (MPI) on 23 December 2005, with 99.5 flight hours accumulated since that service. The investigation focused on the source of the power loss and the mechanics of the touchdown.
Findings
- The primary cause of the power loss was a substantial engine power degradation caused by the failure of the P3 air pipe located near the Governor unit and the FCU.
- The pilot failed to sufficiently cushion the impact forces during the final stages of the autorotative landing, leading to a hard touchdown.