Cause of chopper crash remains a mystery

INVESTIGATORS examining the wreckage of the Super Puma helicopter which crashed last month killing four people say they have found no evidence of a technical failure behind the accident.

In a short two page special bulletin published on Thursday, the Air Accident Investigation Branch said they had successfully downloaded data from the combined voice and flight data recorder (CVFDR) recovered by local divers last week.

The statement aligns with the Civil Aviation Authority who said on Monday they did not believe the accident was caused by “an airworthiness or technical problem”.

Analysis of the black box has now shown that the Super Puma L2 with 18 people on board was on the “published horizontal and vertical profile” three miles from Sumburgh airport on 23 August.

“At about two miles from the runway threshold the helicopter was approximately 240 feet below the vertical approach profile, with a rate of descent of about 500 feet per minute, and an airspeed of 68 knots,” the report says.

“The airspeed continued to reduce to below 30 knots and as it did so the helicopter pitched increasingly nose-up.

“The rate of descent remained constant for a period, before increasing rapidly.

“Shortly thereafter the helicopter, which was intact, struck the sea in a near level pitch attitude with a slight right bank. Both engines were delivering power until impact.”

In its summary, the bulletin concluded: “To date, no evidence of a causal technical failure has been identified; however, detailed examination of the CVFDR data and the helicopter wreckage is continuing.”

The AAIB report gives no hint what actually could have caused the tragic accident.

It described the weather conditions as south easterly 17 knot winds with 2,800 metres visibility in mist and scattered clouds at 200 feet.