What happened
On 16 July 2005, a Bell 206B Jet Ranger III, registration G-CVIP, was conducting a private local area flight near Flecknoe, Warwickshire. The flight, which began at Sywell Aerodrome, included the pilot and three passengers. During the flight, the pilot noted a momentary low voltage warning, but the aircraft continued its mission without further electrical issues.
As the helicopter approached the landing site at Flecknoe at an altitude of approximately 100 ft, the pilot heard an intermittent audio warning followed by a continuous tone. This was accompanied by the illumination of the ROT LOW RPM warning light on the central warning panel. Recognizing the symptoms of power loss, the pilot immediately initiated an engine-off landing procedure.
During the final stages of the descent, at approximately 20 ft, the pilot performed an aggressive flare by raising the collective control lever to reduce the rate of descent. This maneuver was accompanied by a loud bang and violent vibrations throughout the airframe. The helicopter landed on the grass surface, but the impact and control inputs caused the main rotor blades to strike the tail pylon, severing it immediately behind the horizontal stabilizer. There were no fatalities or injuries to the four people on board.
The investigation
The AAIB investigation focused on the cause of the engine power loss and the subsequent structural failure. The engine was removed and subjected to bench testing at an approved facility. The investigation confirmed that the engine met all manufacturer specifications, with no evidence of magnetic chip light indications, abnormal oil consumption, or technical faults found during acceleration and deceleration checks.
Regarding the structural failure, the investigation established that the tail pylon was severed by the main rotor blades during the pilot's attempt to cushion the landing.
Findings
- The pilot's decision to perform an aggressive flare at a low altitude, while intended to reduce the descent rate and avoid a heavy landing, resulted in the main rotor blades contacting the tail pylon.
- There was no technical reason identified for the loss of engine power during the approach.
- The engine was found to be in good working order following post-accident testing.