Super Puma crash might have been prevented

On Wednesday 1 April 2009, a Super Puma helicopter, owned by Bond Offshore Helicopters Limited, was flying over the North Sea, en route from the BP-operated Miller oil platform to Aberdeen, when it plunged into the sea killing all 16 people in the aircraft, 11 nautical miles (20 km) northeast of Peterhead, Scotland .

2009 Super Puma crash might have been avoided

A Fatal Accident Inquiry took place in Aberdeen over a period of six weeks and was presided over by Sheriff Principal Derek Pyle, who today revealed that the accident might have been avoided had the helicopter owner followed the rules  from the aircraft maintenance manual.

In a statement issued today Sheriff Principal Pyle said that spalling, the fracturing of metal in the gearbox, was the most probable cause of the accident.

To be more precise, the statement reads that the reason the helicopter crashed was a catastrophic failure of the main rotor gearbox of the said helicopter on the said date, which was as a result of a fatigue fracture of a second stage planet gear in the epicyclic module.   The fatigue fracture of the second stage planet gear in the epicyclic module was caused by spalling.

The primary means of ensuring that spalling does not result in gearbox failure is through regular maintenance.

Bond failed to act by the book

In its report, Sheriff Principal said that Bond Offshore Helicopters failed to follow the correct task in the aircraft maintenance manual on the discovery of a metal particle which would have resulted in the removal of the epicyclic module and an examination of the magnets on the separator plates.

Sheriff Pyle also said that Bond failed to ensure that communications with the manufacturer of the helicopter, Eurocopter, on 25 March 2009, were done in accordance with the recognised procedures, with the result that misunderstandings arose between the parties, which contributed to the failure by Bond to act by the book.

However, Sheriff Principal said that there is not a great deal of evidence to support the view that if Bond had removed the epicyclic module they would have found sufficient evidence of particles on the magnets to warrant removing the gearbox from service.

The Sheriff Principal report says that the essential fact is that everyone in the company [Bond Offshore Helicopters] well knew that maintenance must be done by the book. “On one occasion, that fundamental rule was broken. It resulted in the failure to detect a significant fault in the helicopter’s gearbox, which possibly – but only possibly – resulted in the crash,” Sheriff Pyle said.

Bond Offshore Helicopters message

In response to the Sheriff Principal Derek Pyle’s determination Bond Offshore Helicopters issued the following statement:

“Bond Offshore hopes that Sheriff Principal Derek Pyle’s determination today (March 13th) brings a degree of closure to the families, friends and dependents of those who died in the tragedy of 2009. We at Bond also lost friends and colleagues that day.”

“Although Sheriff Principal Pyle has indicated that spalling was, on balance, the most likely reason for the catastrophic gearbox failure which caused the accident – a view not shared by the independent Air Accident Investigation Branch – he did find that this was not proved beyond reasonable doubt.”

“We are pleased the Sheriff Principal recognised that Bond engineers understood the vital importance of their role in ensuring the safety of their pilots and passengers. But we have always accepted that we made mistakes through honest confusion over telephone calls and emails. Lessons needed to be learned, lessons have been learned and lessons continue to be learned. We are absolutely committed to continuing to drive safety improvements across the business, and will study the Sheriff Principal’s recommendations carefully, along with our industry colleagues.

“We would like to express again our deep sorrow at the sixteen lives lost in 2009. We owe it to their memories, and to the 160,000 men and women we carry every year, to continue to deliver the highest standards of safety in everything we do.”

The crash

It was a routine flight, one which is done on numerous occasions each day to ferry workers to and from the North Sea oil fields. The weather was clear and sunny and the sea was calm. On board was the pilot, Paul Burnham. He was 31 years of age. He was assisted by his co-pilot, Richard Menzies. He was 24. They were responsible for the 14 passengers on board. They all worked on the platform. The youngest, James Costello, was 24; the oldest, David Rae, was 63. All, bar three, lived in Aberdeen or elsewhere in Scotland. Two, James Edwards and Nolan Goble, lived in England. One, Mihails Zuravskis, came from Riga in Latvia.

At 1.54 pm,Menzies contacted Air Traffic Control at Aberdeen Airport to advise that they expected to arrive there in 20 minutes. Six seconds later, a warning appeared on the helicopter’s flight deck indicating low oil pressure in the main gearbox. This was immediately followed by a grinding noise which lasted for four seconds. It was accompanied by a sudden increase in airspeed from 140 to 170 knots and a sudden increase in pressure altitude. Six seconds later, Burnham issued a mayday call, which was followed by a further one five seconds later by Menzies.

The grinding noise which the pilots had heard was the beginning of the break-up of the main gearbox which was attached to the main rotor. Twenty seconds after the appearance of the oil warning light the main rotor broke away and then severed the tail boom in a series of strikes. The fuselage began a rapid descent into the sea.

At that time, Lidvar Hildre, a ship’s mechanic on a platform supply ship, the Normand Aurora, was painting a cargo rail. As he looked out on the starboard side he suddenly saw, about two nautical miles away, a helicopter falling into the sea. There was a large splash followed by a bang and white smoke. He then saw four rotor blades all attached together falling out of the sky and hitting the sea close to where the helicopter was. Captain Arne Lystad immediately gave the order to launch the fast rescue boat, as the ship itself turned to go full speed to the crash site. By this time, Her Majesty’s Coastguard had launched a major search and rescue operation which involved five aircraft, including helicopters and an RAF Nimrod. Ten vessels responded to a request to assist in the search.

No survivors were found.  By 6 April, all the bodies and the remains of the helicopter had been recovered and taken to Aberdeen.

The victims were Captain Paul Burnham, 31, of Methlick, Aberdeenshire, and co-pilot Richard Menzies, 24, of Droitwich Spa, who worked for Bond Offshore Helicopters.

The KCA Deutag employees killed were Brian Barkley, 30, of Aberdeen; Vernon Elrick, 41, of Aberdeen; Leslie Taylor, 41, of Kintore, Aberdeenshire; Nairn Ferrier, 40, of Dundee; Gareth Hughes, 53, of Angus; David Rae, 63, of Dumfries; Raymond Doyle, 57, of Cumbernauld; James John Edwards, 33, of Liverpool; Mihails Zuravskis, 39, from Latvia; and Nolan Carl Goble, 34, of Norwich.

The other named victims were James Costello, 24, of Aberdeen, who was contracted to Production Services Network (PSN); Alex Dallas, 62, of Aberdeen, who worked for Sparrows Offshore Services; Warren Mitchell, 38, of Oldmeldrum, Aberdeenshire, who worked for Weatherford UK; and Stuart Wood, 27, of Aberdeen, who worked for Expro North Sea Ltd.

 

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Offshore Energy Today Staff, March 13, 2014