History of the Flight
The pilot, a 50-year-old private pilot with 108 hours total (all on type), planned to take two passengers to a friend's farm in Holmfirth. He intended to land in a nearby field, aware of obstacles including trees, power lines, and sloping ground. He planned to make an out-of-ground-effect (OGE) hover to visually assess the landing spot.
The takeoff at 1435 hrs and the 20-minute VFR flight were uneventful. The pilot identified the destination field and conducted two overflights to assess the landing point. He observed overhead domestic power lines along the southern edge and a wind turbine nearby, which indicated wind direction.
He made a steep approach to clear the power lines but realized he was running out of room to land and raised the collective lever to slow down. Insufficient power was available to arrest his descent; at about 6 ft above ground, the low rpm warning horn sounded and the rpm warning light illuminated. The helicopter yawed through 180° before striking the ground hard in a flat, slightly tail-down attitude.
The pilot shut down the aircraft, and all three occupants vacated without assistance. There was no fuel leak or fire.
Accident Site
The aircraft landed in a field with undulating, sloping, and boggy ground. Power lines ran along the south and south-east edges; a wind turbine was to the south. Ground impact marks were directly below the tail rotor, where blades had struck the soft grass. The tail rotor blades were bent and twisted, with one broken near the root.
Damage included a fractured tail rotor shaft, damaged tail rotor, bent landing skids, disrupted cockpit seat structure and keel panels, and damage to the belly. The fuel mixture control was pushed in and guarded; the carb-heat lever was unlatched and halfway out.
Aircraft Information
The Robinson R44 Clipper I is a four-seat light helicopter powered by a single Lycoming O-540-F1B5 piston engine. The carburettor system features a heat assist function tied to collective lever movement.
Meteorological Conditions
Walton Wood Airfield reported dry, bright weather with good visibility. The Leeds/Bradford METAR at 1450 showed wind from 210° at 14 kt, visibility >10 km, temperature 8°C, dew point 5°C, and QNH 1009 hPa.
Downwind Approach
Video footage showed exhaust smoke blowing north after landing, indicating a downwind approach. This was confirmed by the wind turbine direction, showing the prevailing wind behind the aircraft during approach.
Pilot's Assessment
The pilot acknowledged misjudging wind direction, contrary to his mental picture. On final, he increased speed from 40 to 50 mph, with a descent rate of 500 fpm. After clearing power lines, he realized high groundspeed forced a deceleration sooner and at greater height than planned, requiring more power. He intended to raise the collective at 20-30 ft to flare and transition to a hover but found insufficient power, despite seeming power reserve during overflights. At about 100 ft, wind appeared to suddenly reduce, possibly due to valley terrain. He thought the aircraft entered a vortex ring state, causing rapid descent; the sudden right yaw was too rapid to correct.
Survivability
Soft ground, cockpit seats, and skids absorbed vertical impact. The pilot and passengers later reported neck and lower back pains.