The divers combing the wreckage of the Super Puma helicopter that crashed off Shetland had to work at the edge of their safety zone, with the sea crashing against the rocks around them, to find the aircraft’s black box.
The Air Accidents Investigation Branch (AAIB) was desperate to find the flight data recorder to find out exactly why the aircraft carrying 18 people suddenly fell into the sea shortly before reaching Sumburgh Airport, with the loss of four lives, including Gary McCrossan from Inverness and Sarah Darnley, from Elgin.
By last Wednesday morning, five days after the fatal accident, the AAIB team knew the black box lay within a large area at the point of Garths Ness, by Quendale Bay, because it was still sending out a radio signal.
However, with the signal ricocheting off the rocks, they could not pinpoint its location, and the heavy swell meant they could not take the large dive boat Bibby Polaris close enough in for divers to investigate properly.
That day, the AAIB requested the help of local firm Ocean Kinetics, which assembled a team of four divers and a boatman and took a 20ft aluminium boat with a hydraulic winch to within a short distance of the rocky shoreline.
Working under supervisor Roger Goudie, they dived the steep shoreline, which dropped rapidly, with rocky shelves that were covered with debris from the helicopter.
READ MORE: Full coverage of the Super Puma disaster
At teatime on Wednesday, the team aborted their dive and took their boat farther north along the Quendale Bay side of Garths Ness.
Ocean Kinetics managing director John Henderson, who was one of the divers, said: “We knew there had been debris spotted on the surface north of there and I soon found the gearbox with the rotor attached.
“We also found two engines and part of the cockpit and some personal items, some of the kitbags the guys had taken offshore.”
The team returned the following day, by which time the conditions had improved slightly.
Mr Henderson and his crew went back in and, about 1pm, they tracked down the helicopter’s tail section with the brick-sized black box bolted inside.
“We lifted the tail section on board the workboat Koada and, as soon as the AAIB guys unbolted the black box and flew away, they were delighted.
Mr Henderson said the weather conditions made it “a very difficult operation” that involved them working at the “extreme end of the safety zone”.
Meanwhile, a service of celebration for Sarah Darnley will be held on Monday in Moray Crematorium. The family says donations to local charities may be given at the crematorium door.