1986 British International Helicopters Chinook crash

Sumburgh disaster

Boeing-Vertol 234 G-BISP operated by British Airways Helicopters, predecessor to British International Helicopters
Accident summary
Date	6 November 1986
Summary	Mechanical failure
Site	2.5 miles east of Sumburgh Airport 59°53.5′N 1°12′W / 59.8917°N 1.200°W / 59.8917; -1.200Coordinates: 59°53.5′N 1°12′W / 59.8917°N 1.200°W / 59.8917; -1.200
Passengers	44
Crew	3
Fatalities	45
Injuries (non-fatal)	2
Survivors	2
Aircraft type	Boeing 234LR Chinook
Operator	British International Helicopters
Registration	G-BWFC
Flight origin	Brent Platform 'C'
Destination	Sumburgh Airport

The Sumburgh disaster was the crash of a Boeing 234LR Chinook helicopter on 6 November 1986 with a loss of 43 passengers and two crew members. The helicopter was on approach to land at Sumburgh Airport Shetland Islands returning workers from the Brent oilfield. At 2.5 miles (4.0 km) from the runway the helicopter had a catastrophic forward transmission failure which de-synchronised the twin rotors causing the blades to collide. The helicopter crashed into the sea and sank.

The helicopter was normally based at Aberdeen Airport but had been based at Sumburgh Airport since 3 November 1986 to operate a shuttle service from the Brent oilfield in the East Shetland Basin. On 6 November the first flight was delayed due to an oil leak from an engine gearbox that was soon rectified and the aircraft left Sumburgh at 08:58 with 40 passengers for the Brent Field. The aircraft visited three platforms with exchanges of freight and passengers then departed Brent Platform C at 10:22 with 44 passengers on board for return to Sumburgh Airport. It transited at a height of 2,500 feet (800 m), and as it approached Sumburgh it was cleared to descend to 1,000 feet (300 m). Reporting 4.5 miles (7.2 km) from the airfield, the controller cleared it to land on helicopter runway 24. Nothing else was heard.

The crew noticed an increased noise level in the flightdeck followed by a bang. Despite applying full cyclic pitch control the aircraft did not respond and nose-dived towards the sea from a height of 150 feet (50 m). The helicopter hit the sea, broke up and sank. A Coastguard search and rescue helicopter which had just departed Sumburgh Airport reported liferafts in the sea. It then observed a survivor clinging to a substantial piece of wreckage. While they winched the man on board another survivor was noted amongst the floating bodies. With no signs of other survivors the Coastguard helicopter flew the survivors to Lerwick for transfer to hospital. An air and sea search failed to find any more survivors but all the floating bodies were recovered and brought to the airport.