Just before 2:00 pm on 1 April 2009, Bond Offshore Helicopters Flight 85N crashed north-east of

Peterhead Peterhead (; gd, Ceann Phàdraig, sco, Peterheid ) is a town in Aberdeenshire, Scotland. It is Aberdeenshire's biggest settlement (the city of Aberdeen itself not being a part of the district), with a population of 18,537 at the 2011 Census. ...

, Scotland in the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian ...

while returning from a BP

oil platform An oil platform (or oil rig, offshore platform, oil production platform, and similar terms) is a large structure with facilities to extract and process petroleum and natural gas that lie in rock formations beneath the seabed. Many oil platfor ...

in the

Miller oilfield The Miller oilfield is a deep reservoir under the North Sea, 240 kilometres north-east of Peterhead in UKCS Blocks 16/7b and 16/8b. It was discovered in 1983 by BP in a water depth of 100 metres. Production from Miller field started in June 1992 ...

, north-east of Peterhead. The crash killed all sixteen people aboard. The flight was operated using a Eurocopter AS332L2 Super Puma Mk 2 belonging to

Bond Offshore Helicopters Offshore Helicopter Services (OHS) (known as Bond Offshore Helicopters until April 2016) is a British helicopter operator, specialising in providing offshore helicopter transportation services to North Sea and Irish Sea oil and gas platforms. C ...

. The cause of the crash was main rotor separation following a catastrophic gearbox failure. The helicopter was flown by Captain Paul Burnham and co-pilot Richard Menzies, both working for Bond Offshore Helicopters. Most of the victims were employees of KCA Deutag Drilling. Bond also operated a very similar

Eurocopter EC225 The Airbus Helicopters H225 (previously Eurocopter EC225 Super Puma) is a long-range passenger transport helicopter developed by Eurocopter as the next generation of the civilian Super Puma family. It is a twin-engined aircraft and can carry up ...

LP helicopter which ditched in the North Sea on 18 February 2009, in which all 18 aboard were rescued. The most serious North Sea helicopter accident was the

1986 British International Helicopters Chinook crash On 6 November 1986, a Boeing-Vertol Model 234LR Chinook helicopter returning workers from the Brent oilfield crashed on approach to land at Sumburgh Airport in the Shetland Islands. At from the runway the helicopter had a catastrophic forwa ...

, when a Boeing 234 Chinook crashed, killing 45 people.

Recovery

The search for survivors was called off on the evening of 2 April, rescuers admitting that there was no chance of finding anyone alive, and the seismic survey vessel ''Vigilant'' returned to Peterhead on 4 April. The eight bodies found a few hours after the crash were taken to Aberdeen and then on to a police mortuary. The

Air Accidents Investigation Branch The Air Accidents Investigation Branch (AAIB) investigates civil aircraft accidents and serious incidents within the United Kingdom, its overseas territories and crown dependencies. It is also the Space Accident Investigation Authority (SAIA ...

(AAIB) chartered the ''Vigilant'' for its initial investigation, which arrived on site on 3 April, carrying specialised sonar equipment to locate the wreckage on the seabed. No

EPIRB An Emergency Position-Indicating Radio Beacon (EPIRB) is a type of emergency locator beacon for commercial and recreational boats, a portable, battery-powered radio transmitter used in emergencies to locate boaters in distress and in need of ...

beacon signal had been reported. Grampian Police stated on the evening of 4 April that they had identified the eight bodies that were initially recovered from the surface of the sea. A second vessel, the Diving Support Vessel ''Bibby Topaz'', was chartered to assist the work, and sailed from Peterhead on 4 April, to recover the remaining eight bodies that were not found on the surface, as well as wreckage and the cockpit voice and

flight data recorder A flight recorder is an electronic recording device placed in an aircraft for the purpose of facilitating the investigation of aviation accidents and incidents. The device may often be referred to as a "black box", an outdated name which has ...

s. The wreckage of the Super Puma was located on the sea bed at a depth of by the ''Bibby Topaz''. The remaining eight bodies were recovered from inside the fuselage. The combined FDR/CVR was recovered and sent to the Farnborough headquarters of the AAIB for analysis, as was all the wreckage.

Investigation

The AAIB invited the

Bureau d'Enquêtes et d'Analyses pour la sécurité de l'Aviation Civile The Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA, ) is an agency of the French government, responsible for investigating aviation accidents and incidents and making safety recommendations based on what is learned from those inve ...

(BEA),

Eurocopter Airbus Helicopters SAS (formerly Eurocopter Group) is the helicopter manufacturing division of Airbus. It is the largest in the industry in terms of revenues and turbine helicopter deliveries. Its head office is located at Marseille Provence A ...

, the

European Aviation Safety Agency The European Union Aviation Safety Agency (EASA) is an agency of the European Union (EU) with responsibility for civil aviation safety. It carries out certification, regulation and standardisation and also performs investigation and monito ...

(EASA), and the UK

Civil Aviation Authority A civil aviation authority (CAA) is a national or supranational statutory authority that oversees the regulation of civil aviation, including the maintenance of an aircraft register. Role Due to the inherent dangers in the use of flight vehicles, ...

to participate. The AAIB released a third press statement on 4 April 2009 stating that work to recover the wreckage of G-REDL was continuing. On 11 April the AAIB released its initial report into the accident in which it stated that the immediate cause of the accident was a "catastrophic failure of the main rotor gearbox" and the consequent detachment of the main rotor. Three safety recommendations were made, the first of which was that all Super Puma helicopters should receive additional checks on the main rotor gearbox

epicyclic An epicyclic gear train (also known as a planetary gearset) consists of two gears mounted so that the center of one gear revolves around the center of the other. A carrier connects the centers of the two gears and rotates the planet and sun gea ...

module. On 17 April the AAIB released a second report noting that metallic debris from the gearbox had been detected 34 flying hours prior to the helicopter crash. However, "no signs of an incipient gearbox failure were detected". In response, the EASA ordered an "urgent" inspection of the gearboxes on both the AS332L2 Super Puma and the EC225LP Super Puma. Helicopter operators were given to 24 April to complete the inspections. AAIB Ref: EW/C2009/04/01 On 16 July the AAIB published AAIB Special Bulletin: 5/2009 detailing further progress in the investigation, including two further safety recommendations 2009–74 and 2009–75. These respectively called on the EASA to urgently review the manuals on magnetic particle detection and on planetary gear inspection. On 24 November 2011 the AAIB published its Formal Report 20/2011 into the accident. The cause of the accident was attributed to the catastrophic failure of the Main Rotor Gearbox as a result of a fatigue fracture of a second stage planet gear in the epicyclic module. In addition the investigation identified three contributory factors: # The actions taken following the discovery of a magnetic particle on the epicyclic module chip detector on 25 March 2009, 36 flying hours prior to the accident, resulted in the particle not being recognised as an indication of degradation of the second stage planet gear, which subsequently failed. # After 25 March 2009, the existing detection methods did not provide any further indication of the degradation of the second stage planet gear. # The ring of magnets installed on the AS332 L2 and EC225 main rotor gearboxes reduced the probability of detecting released debris from the epicyclic module. Seventeen Safety Recommendations were made as a result of the investigation. On 13 March 2014, an official UK government inquiry found that the accident could have been prevented if maintenance procedures had been correctly followed.

Recovery

Investigation

See also

References

Further reading