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By Belinda Goldsmith
LONDON, Aug 29 (Reuters) - A British safety group onThursday ended a six-day suspension of flights by Super Pumahelicopters in the North Sea, imposed after four oil rigcontractors were killed in a crash last week.
Although the cause of last Friday's fatal accident nearScotland's Shetland Islands remains unknown, the HelicopterSafety Steering Group (HSSG) said there was no evidence tocontinue a suspension on flights put in place on Saturday.
The grounding of all types of Super Puma helicopters, whichmake up about half of a 75-strong fleet used to carry workers toand from UK offshore platforms, left North Sea operators tryingto find alternative ways of transporting staff and supplies.
HSSG spokesman Les Linklater said several aviationauthorities, a pilots' union and helicopter operators themselveshad expressed confidence in the aircraft made by Eurocopter, aunit of Europe's top aerospace group EADS.
He said three types of Super Pumas - L, L1 and EC225s -would return immediately to service but the Super Puma L2 modelinvolved in Friday's fatal crash would initially bere-introduced for non-passenger operations only.
"There is no evidence to support a continuation of thetemporary suspension of the entire Super Puma fleet," Linklatersaid in a statement following a two-day meeting.
The crash was the fifth accident in four years in the areainvolving different models of Super Pumas which included a fatalcrash of an L2 in April 2009 in which 16 people were killed.
It came as the helicopter industry tries to rebuildconfidence after two EC225 aircraft ditched in the North Sealast year due to gearbox problems and the aircraft was suspendedin the area for almost 10 months until July this year.
The North Sea is one of the world's largest oil and gasproducing regions with almost 57,000 workers travelling tooffshore facilities in the area last year and safety issues arewatched closely by regulators worldwide.
BLACK BOX FOUND
Britain's Air Accident Investigation Branch (AAIB) said onThursday that a search team had found the black box fromFriday's crash with flight data and cockpit recordings whichwould now be examined to try to establish the cause.
The AAIB said the helicopter appeared upright and intactwhen it entered the water, slowing down before it crashed.
The union Unite said the continued grounding of the L2 fleetwas the bare minimum the industry could do until the recoveredblack box's data fully established what happened.
"Confidence has been shattered and the industry needs toprovide substantive evidence - not opinion - to its workersdemonstrating the airworthiness of the helicopters that are nowreturning to operations," Unite Scottish Secretary Pat Raffertysaid in statement.
An online petition urging for all Super Pumas to be bannedhas gained more than 12,000 signatures and a Facebook pagecalled "Destroy The Super Pumas" has 37,500 likes.
Linklater said the accident was a tragedy but there arealmost 16,000 people offshore currently, including about 250people who have spent more than 21 days offshore.
"We have a duty of care to all offshore workers both interms of their safety and their well-being," he said, adding asympathetic approach would be taken to workers who did not feelthey could fly.
The suspension of Super Puma flights was causing delays andflight backlogs as the rest of the fleet, comprised mainly ofU.S. manufactured Sikorsky Aircraft, a unit of UnitedTechnologies Corp, tried to meet demands.
But the industry is used to short-term disruptions caused bybad weather and changes schedules to shift non-essentialmaintenance activity to reduce impact on production.
Spokesmen for France's Total, BP and Royal Dutch Shell said production was not impacted.
