Accident
On 6 June 2015, a Bell 206B Jet Ranger II helicopter, registration G-RAMY, was destroyed in an accident near Creg-ny-Baa, Isle of Man. The sole pilot, who held a Private Pilot's Licence (Helicopter) and had 786 total flying hours (including 126 on helicopters and 71 on the Bell 206), sustained fatal injuries. The aircraft, manufactured in 1974 and powered by a single Allison 250-C20 turboshaft engine, was being operated on a private flight.
History of the Flight
The helicopter had departed from a private landing site in Bedfordshire earlier that morning with the pilot and two passengers. After landing at an unprepared site near Creg-ny-Baa and disembarking the passengers, the pilot shut down the engine and later restarted it. Around 0804 UTC, the helicopter lifted off and initially flew south-westerly before turning right onto a north-easterly track toward Windy Corner. No radio communications were received by Ronaldsway Air Traffic Control.
Witnesses reported seeing the helicopter flying relatively low—estimated between 100 and 300 ft agl—at moderate speed. The fuselage began to oscillate in roll pendulously through a few tens of degrees each way. Subsequently, the fuselage completely rotated in yaw beneath the rotor disc more than once, and the nose pitched up into the rotor disc, causing the aircraft to break apart. The fuselage, rotors, and debris fell separately to the ground; the impact was not survivable.
Aircraft and Pilot Information
The pilot, aged 48, had learned to fly fixed-wing aircraft before obtaining a PPL(H) on the Robinson R22 in 2005, later adding a Bell 206 type rating. His flying instructor noted very good retention of skills and general handling. The pilot discussed his Isle of Man flight plan with her, including fuel planning and alternate landing sites, and she considered him properly prepared. A post-mortem examination determined the pilot died of multiple injuries; the severity of hand injuries suggested he had his hands on the controls at impact and was conscious. Toxicology analyses were negative, and no natural disease played a role.
Meteorological Conditions
The Ronaldsway TAF issued at 0400 UTC forecast surface wind from 230° at 28 kt gusting to 38 kt, with good visibility and a cloud base of 2,500 ft aal. Anemometer data from Brandywell, 1.5 nm north-north-east of the accident site, recorded winds from 220-230° with gusts up to 46 kt around the time of the accident. The terrain near Creg-ny-Baa features a valley that likely funneled the wind toward the accident site. An air ambulance pilot who landed shortly after described the wind as extreme (40 kt or higher) with associated turbulence, deeming the conditions unsuitable for a private pilot with the accident pilot's flying hours.
Wreckage Examination
Examination of the wreckage revealed a catastrophic failure of the main rotor mast in flight. Clear evidence indicated heavy mast bumping contact between the teeter (static) stops on the main rotor head and the main rotor mast. This was consistent with the observed behavior, where the pilot appeared to be attempting to control the aircraft in turbulent conditions. The aircraft was destroyed.
Probable Cause
The investigation identified the probable cause as a catastrophic failure of the main rotor mast due to heavy mast bumping, consistent with the pilot attempting to control the aircraft in turbulent conditions.