LONDON, Aug 29 (Reuters) - A team investigating a fatal helicopter crash in the North Sea near Scotland's Shetland Islands said on Thursday it had retrieved the aircraft's "black box" flight recorder which could help determine the cause of the accident.
Four oil rig contractors were killed when a Super Puma L2, made by EADS unit Eurocopter, crashed into the sea off Shetland's rocky southern coast on Friday night.
The helicopter, carrying 16 passengers and two crew, was operated by CHC Helicopter for France's Total .
Oil and gas operators voluntarily agreed on Saturday to halt flights of all Super Puma helicopters until the cause of the accident could be determined and Britain's Helicopter Safety Steering Group was meeting on Thursday to discuss the grounding.
Britain's Air Accident Investigation Branch (AAIB) said a search team had found the black box that holds flight data and cockpit voice recordings. It said it would be taken to the AAIB headquarters in Farnborough, southern England.
The AAIB said the helicopter had appeared to show a "reduction in airspeed accompanied by an increased rate of descent" before the accident.
This was the fifth accident in four years in the area involving different models of Super Puma helicopters, which make up about half of the 75-strong fleet used to carry workers to and from UK offshore platforms.
The rest of the fleet comprises mainly U.S. manufactured Sikorsky Aircraft, a unit of United Technologies Corp.