UK-based international helicopter operator Bristow lost two of its helicopters last week, one of them in a fatal accident during a North Sea oil support operation and the other in a non-fatal incident on search and rescue duties.

The fatal accident occurred in good weather and in daylight on 16 July when a Sikorsky S-76 went out of control near the North Sea Santa Fe Monarch gas platform off the English east coast. There was no emergency call from the two pilots, who, along with the nine passengers on board, were feared dead by 18 July.

Bristow confirms the helicopter was fitted with a health and usage monitoring system, a pro-active diagnostic system intended to predict trouble before it happens, and says it is looking at making some of the exceedance tolerances finer on its S-76 fleet to see if it yields any clues on the other airframes.

Bristow says it has not grounded its S-76s, but Shell Oil, whose employees were on board the helicopter, says it does not want its workers to travel on the type "until more is known" about this accident.

The last oil-support helicopter disaster was in bad weather in March 1992, when 11 men died on a shuttle between two platforms.

The 15 July non-fatal Sikorsky S-61N Mk II accident was caused by a serious engine mechanical failure and fire, but the pilot was able to land the aircraft safely and evacuate the crew. The helicopter was destroyed by fire.

Source: Flight International