History of the Flight
The pilot, aged 39, held a Private Pilot's Licence with 112 hours total flying experience, of which 8 were on type. He hired the Hughes 369HS (registration G-CSPJ) from Biggin Hill Airport for a local flight to the Canterbury area with his wife and 14-month-old son. The family arrived at the operator's offices at about 0745 hrs. The pilot discussed the flight with the Chief Pilot and Operations Manager and confirmed a booking for the following day. The Chief Pilot expressed concern about noise levels inside the helicopter for the child. The pilot had purchased a child-specific headset, deemed sufficient. The family drove to the hangar, where the helicopter had been refuelled and repositioned. The pilot conducted a pre-flight inspection, then secured his son in a child car seat in the rear left seat. The wife sat in the rear right seat. The helicopter was flown from the front left seat, normal for this type.
Accident Sequence
The pilot started the helicopter and called Biggin Hill ATC at 0843 hrs for a VFR flight to the east. He was cleared to hover taxi to Pad One and then given takeoff clearance at 0846:20 hrs. The helicopter departed climbing to an estimated 500 feet above aerodrome level, tracking south-east. At 0848:02 hrs, the Tower Controller instructed the pilot to change to Approach frequency. The pilot did not respond initially; a second call 10 seconds later was acknowledged at 0848:16 hrs. Radar data showed the helicopter entered a left turn at or just before that transmission, continuing until it disappeared from radar at 0848:26 hrs. Witnesses reported seeing the helicopter 'fishtailing' and hearing unusual cyclical noises. One witness heard engine note changes over three seconds, then a left yaw and shallow descent. Another helicopter pilot saw yaw oscillations over five seconds, then a left descending turn, followed by a steep nose-down descent. In the final stage, the helicopter flew low over a house at Cudham Lane South in a nose-down attitude. It rolled left to about 15° bank before disappearing behind trees. A brief radio transmission at 0848:30 hrs was a distressed utterance. The aircraft struck the ground in a 30° nose-down pitch at about 80 kt forward speed, severely disrupting the structure and imparting fatal injuries to the three occupants.
Investigation Findings
The helicopter was destroyed. There was no evidence of pre-impact technical failure; the engine was running at impact. The reasons for the accident could not be determined. Neither a Cockpit Voice Recorder nor a Flight Data Recorder was fitted, as not required on this rented public-transport category helicopter. Two safety recommendations were made concerning installation of new technology cockpit voice recorders on all public transport category aircraft.