Missing part found on Febr 23, 2017: epicyclic gear 2nd stage planet gear carrier
Airbus Helicopters, April 29, 2016 - Airbus Helicopters regrets to confirm that an H225 operated by CHC was involved in a fatal accident off the coast of Norway near Turoey outside Bergen on Friday 29th of April.
Preliminary information obtained indicates that the helicopter was flying from Gullfaks B oil platform and was carrying a crew of 2 people plus 11 passengers from Statoil ASA. Latest reports state that 11 people have died and two are missing.
Airbus Helicopters is deeply saddened by this tragedy. We express our deepest sympathy and our thoughts are with the victims, their relatives, friends and colleagues.
Safety is Airbus Helicopters' top priority and we are providing our full support to both the accident investigators as well as CHC.
Airbus Helicopters teams are fully mobilized to understand the root cause of the accident. At this time we do not have any further information and we will provide relevant update as it becomes available.
CHC Helicopter, April 29, 2016 - CHC Helicopter Service confirms that there has been an accident involving flight HKS 241 from Gullfaks B with estimated time of arrival at Flesland Airport Bergen at 12.04 pm CET. The aircraft involved in the accident is an Airbus EC 225 helicopter with 2 crew and 11 passengers operated for Statoil.
The accident took place approaching Flesland airport. Expected landing was 12:04 pm Norwegian time. CHC Helicopter Service was notified of the incident at 12:05 pm and contacted the appropriate Norwegian authorities. Exact details of the incident are not yet known and CHC is in contact with the Joint Rescue Coordination Center. CHC has also mobilised its emergency response team and next of kin organisation.
Out of respect for passengers and crewmembers, all flights with the aircraft type H225/EC225 have been stopped in the Norwegian sector. Flights with other aircrafts are temporarily halted, and will continuously be evaluated.
Statoil Norway has also opened a next of kin hotline: 800 500 20 and further details will be released when more information becomes available.
Local press contact:
Claus Sonberg, ph + 47 924 62 393 for Norwegian media
Louise Nicolson, ph + 44 7515 881474
CHC press contact
1.214.262.7426
[email protected]
Airbus Helicopters, April 30, 2016 - Airbus Helicopters regrets to confirm that a H225 operated by CHC was involved in a fatal accident off the coast of Norway near Turoey outside Bergen on Friday 29th April.
Preliminary information obtained indicates that the helicopter was flying from Gullfaks B oil platform and was carrying a crew of 2 people plus 11 passengers from Statoil ASA. Latest reports state that 11 people have died and two are missing.
Airbus Helicopters and all of its staff are deeply affected by this tragic accident. We share the pain of the families, friends and colleagues of the victims.
At this point in the investigation, we do not have any information that allows us to understand the causes of the accident that involved the aircraft’s rotor being detached, nor to make any links to events that have occurred previously.
Airbus Helicopters is participating in the on-going investigation and two technical experts are currently on their way to Norway to provide their assistance to the local authorities. In the frame of the investigation, information related to the background of the aircraft is being gathered. The preliminary elements of the inquiry should become available in the coming days.
Under these tragic circumstances, and until these elements are available, we are allied with the decision taken to put all commercial EC225LP passenger flights on hold.
Airbus Helicopters, May 1, 2016 - Considering the additional information gathered during the last 48 hours, Airbus Helicopters’ decision, at this stage, is to not suspend flights of any nature for the EC225LP.
However, out of respect for all those affected by the accident, Airbus Helicopters continues to stand by the decision taken by the Norwegian and UK authorities to put commercial EC225LP passenger flights on hold in Norway and in the UK.
As investigations are progressing, Airbus Helicopters intends to provide an update in the coming days.
Accident Investigation Board of Norway (AIBN), May 1, 2016 - The Accident Investigation Board Norway arrived at the accident site on Turøy in Hordaland Friday evening.
Helicopter wreckage was retrieved from land and the sea bottom Saturday and was then transferred to Haakonsvern naval base (Bergen) by ship. The combined Flight Data and Cockpit Voice Recorder was retrieved from the wreckage Friday night. The unit was taken to AAIB in England where the process of downloading data has started.
Representatives from the French BEA and British AAIB joined the Norwegian investigation team on the accident site Saturday. BEAs specialists are to join the investigation due to the French helicopter manufacturer. Experts from the helicopter and motor manufacturer supports the BEA. The AAIB is joining the investigation because of their recent experience on the helicopter type and offshore operations.
It is difficult to determine an exact timetable for the work ahead but the AIBN team is working as fast as possible to find, if any, safety critical issues as soon as possible. To ensure that important technical findings are communicated to the authorities, both the European Aviation Safety Agency (EASA) and the Norwegian Civil Aviation Agency are invited to join the investigation. Any critical safety information will be communicated. Completing a full investigation including all the factors leading up to the accident will take time, experience suggests at least twelve months.
Today, Sunday, the work continues with search for more parts of the helicopter wreckage both at sea and on land. At the same time, the main wreckage and the large components are brought to Haakonsvern (Bergen) for further investigation.
The data from the recorder, together with an analysis of the accident site and wreckage components, may give knowledge about what happened at the time of the accident and possibly at the time prior to the accident.
Accident Investigation Board of Norway (AIBN), May 2, 2016 - The process of retrieving data from the combined FDR and CRV is completed. The data is of good quality and is sent back to Norway for analysis.
The AAIB has provided their expertise quickly, and ensured that this essential information was secured and handled in the best possible way.
Airbus Helicopters, May 3, 2016 - Airbus Helicopters welcomes the announcement made by the Accident Investigation Board Norway (AIBN) today.
The investigation will now solely be focused on potential root causes of a technical failure, such as design, production, and/or maintenance.
Airbus Helicopters continues to provide its full support to the AIBN investigation.
At this stage and based on the latest information, preliminary inspection of the main gearbox vertical shaft shows no link with the 2012 ditching events.
In addition to the SIN 3031-S-00 and based on the on-going root cause analysis process, precautionary measures are requested:
- An airworthiness directive has been issued requesting measures newly defined in the EASB 53A058 and additional one-off maintenance checks.
- The EASB 53A058 requests the verification of the correct installation of all MGB suspension bar attachments for the EC225LP. Similar measures will be published shortly for the EC725AP in a specific ASB.
European Aviation Safety Agency (EASA), May 3, 2016 - EASA issued an Emergency Airworthiness Directive (AD), following the tragic accident which occurred in Norway on 29 April 2016 to an Airbus Helicopters EC 225 helicopter.
The partial information available so far indicate an in-flight separation of the main rotor from the main gearbox (MGB); an investigation is on-going to identify the root cause of the accident.
EASA AD requires, as a precautionary measure, to perform before next flight certain inspections on the fleet of EC 225 helicopters, and to report any discrepancy to both EASA and Airbus Helicopters.
This AD must be considered an interim action, further mandatory action may follow owing to investigation progress.
View AD 2016-0089-E : Main Rotor Drive(s) – Inspection
CHC Helicopter, May 3, 2016 - Following Friday’s tragic accident involving an EC 225, CHC immediately put all EC 225 flights temporarily on hold with the exception of those aircraft dedicated to life-saving search-and-rescue missions.
Based on the information available to-date, the Accident Investigation Branch Norway (AIBN) has stated that the EC225 LP helicopter suffered in-flight separation of the main rotor hub from the main gearbox (MGB); the root cause has yet to be identified. As a precautionary measure, and while investigations are ongoing, Airbus Helicopters has issued an Emergency Airworthiness Service Bulletin (EASB) 553-A-058, which calls for checks on the installation of the suspension bars.
Subsequently EASA has issued Emergency Airworthiness Directive (EAD) 2016-0089. The EAD mirrors the requirements of the EASB while additionally requiring checks on the main gearbox chip detector and the oil filter for contamination. It also requires the verification of HUMS data. The EAD is considered to be an interim action and further mandatory action may follow.
Airbus Helicopters has since updated their original EASB and have today (Wednesday May 4) issued a Revision 1 to EASB 553-A-058 which effectively mirrors the additional requirements of the EAD.
CHC is complying fully with the requirements of both the EASBs and EAD in addition to any ongoing commercial operational limitations laid down by Regulatory Authorities.
While CHC recognises the additional assurances provided by the EASBs and EAD, we consider continuing to place all EC225 commercial flights around the world on hold to be the most prudent course of action.
CHC remains focused on safely delivering as much capacity as possible using available resources
Accident Investigation Board of Norway (AIBN), May 4, 2016 - The European Aviation Safety Agency EASA published late Tuesday May 3rd an emergency airworthiness directive (AD) concerning the helicopter type involved in the accident at Turøy 29 April. CAA-N has reviewed the content of this directive and has decided to maintain the flight operation stop for helicopter type Airbus EC225LP.
CAA-N has been working intensely with follow up of the accident since the first report came. Shortly after the accident, the CAA-N published a safety directive to stop flights with helicopter type EC225LP. British aviation authorities issued the same restrictions to their operators.
The EASA airworthiness directive published late May 3 entered immediately into force. The directive establishes specific technical inspections to be carried out before the first flight of EC 225 LP after the effectuation of the directive.
CAA-N has considered the directive and has concluded to maintain the temporary flight operation stop for Norwegian helicopters Airbus EC225LP.
The cause of the accident at Turøy is still unknown. Our focus is therefore to ensure that the underlying cause of the accident is found, we are therefore working in close relationship the Accident Investigation Board, British aviation authorities, EASA and other key parties.
Accident Investigation Board of Norway (AIBN), May 11, 2016 - Following the tragic Norwegian Super Puma helicopter accident on Friday 29 April, the UK and Norwegian Civil Aviation Authorities have been collaborating very closely and are united in their approach.
Shortly after the accident, both organisations introduced restrictions to the Airbus EC225LP helicopter to prevent operators using it for commercial flights. Both organisations have now also agreed to extend the scope of the restriction to include the AS332L2 Super Puma helicopter until further information is available. The decision to extend the restriction is based on the close similarities between the two types of helicopter and neither helicopter can be used by either UK or Norwegian operators for commercial flights.
The restrictions do not apply to search and rescue flights.
The accident remains under investigation by the Norwegian authorities and we remain in close contact with all offshore helicopter operators to continue to assess the situation.
Accident Investigation Board of Norway (AIBN), May 13, 2016 - Update on the progress of the investigation : Preliminary report May 13, 2016
Accident Investigation Board of Norway (AIBN), May 27, 2016 - 29 April 2016 the Main Rotor Head (MRH) and mast suddenly detached from an Airbus Helicopters H225 enroute from Gullfaks B to Bergen Airport Flesland. The helicopter impacted on a small island east of Turøy. All 13 people on board perished.
AIBN is now performing detailed examinations of particular components of the helicopter. The examinations are performed in Norway, England and France. The organized search for parts on land and in the sea is temporarily paused. However, important components are still missing, and the AIBN will likely resume the search in June.
The first preliminary report was published on 13 May 2016. An updated preliminary report issued on 27 May 2016 : At this stage, the AIBN can confirm that the scenarios under consideration include failure of epicyclic module, suspension bar (lift strut) attachment and MGB conical housing.
European Aviation Safety Agency (EASA), June 2, 2016 - Emergency Airworthiness Directive 2016-0104-E which prohibits any flights of AS332L2 and EC225 helicopters with the exception of a single flight without passengers to ferry such a helicopter to a maintenance base.
Accident Investigation Board of Norway (AIBN), June 28, 2016 - At this stage of the investigation, the AIBN finds that the accident most likely was a result of a fatigue fracture in one of the eight second stage planet gears. It appears that the fracture has propagated in a manner which is unlikely to become detected by existing mandatory or supplementary systems for warning of an imminent failure. What initiated the fracture has not yet been determined.
Accident Investigation Board of Norway (AIBN), Feb 8, 2017 - 29 April 2016 the Main Rotor Head (MRH) and mast suddenly detached from an Airbus Helicopters EC 225 LP enroute from Gullfaks B to Bergen Airport Flesland. The helicopter impacted on a small island east of Turøy. All 13 people on board perished. The investigation has shown that the accident was a result of a fatigue fracture in one of the eight second stage planet gears, with clear similarities to the G-REDL accident off the coast of Scotland in 2009. It appears that the fracture propagated in a manner which was unlikely to be detected by the mandatory or supplementary systems intended for warning of an imminent failure.
The investigation is complex, and has a wide scope. So far, the metallurgical studies have been a major focus. These are efforts to map and understand why fatigue cracks could form and evolve. This work has not yet been completed.
At present time, the primary focus of the AIBN investigation is certification aspects of the main gearbox and the robustness of past and present design requirements. This includes the follow-up on safety recommendations issued by the AAIB in connection with the accident involving G-REDL and continuing airworthiness of the gearbox. This work requires good collaboration with the responsible entities, primarily the helicopter manufacturer and the European Aviation Safety Authority (EASA).
The scope and complexity of the investigation means that it is not feasible to estimate a completion date for the final report. The investigation continues with the same high activity. Aviation authorities in Norway and Europe are continually updated about the investigation.
The AIBN intends to issue a new preliminary report on 29 April 2017, unless there are significant new discoveries necessitating an interim report in the meantime.
Accident Investigation Board of Norway (AIBN), Feb 23, 2017 - At Thursday 23 February, the Norwegian Naval Diving School found a vital missing part in connection with the ongoing investigation.
The epicyclic gear 2nd stage planet gear carrier was found in the sea between the area of the main rotor separation and the crash site. The carrier will be subject to further investigations.
Accident Investigation Board of Norway (AIBN), July 2018 - The investigation has shown that the combination of material properties, surface treatment, design, operational loading environment and debris gave rise to a failure mode which was not previously anticipated or assessed.
There are no connections between the crew handling and the accident. Nor is there any evidence indicating that maintenance actions by the helicopter operator have contributed to this accident. The failure developed in a manner which was unlikely to be detected by the maintenance procedures and the monitoring systems fitted to LN-OJF at the time of the accident.
From this investigation there are significant lessons to be learned related to gearbox design, safety assessment, fatigue evaluation, condition monitoring, certification requirements and continued airworthiness of the AS 332 L2 and the EC 225 LP helicopters, which also could be valid for other helicopter types.
Based on this investigation, the AIBN issues 12 safety recommendations. July 2018 Report
Preliminary information obtained indicates that the helicopter was flying from Gullfaks B oil platform and was carrying a crew of 2 people plus 11 passengers from Statoil ASA. Latest reports state that 11 people have died and two are missing.
Airbus Helicopters is deeply saddened by this tragedy. We express our deepest sympathy and our thoughts are with the victims, their relatives, friends and colleagues.
Safety is Airbus Helicopters' top priority and we are providing our full support to both the accident investigators as well as CHC.
Airbus Helicopters teams are fully mobilized to understand the root cause of the accident. At this time we do not have any further information and we will provide relevant update as it becomes available.
CHC Helicopter, April 29, 2016 - CHC Helicopter Service confirms that there has been an accident involving flight HKS 241 from Gullfaks B with estimated time of arrival at Flesland Airport Bergen at 12.04 pm CET. The aircraft involved in the accident is an Airbus EC 225 helicopter with 2 crew and 11 passengers operated for Statoil.
The accident took place approaching Flesland airport. Expected landing was 12:04 pm Norwegian time. CHC Helicopter Service was notified of the incident at 12:05 pm and contacted the appropriate Norwegian authorities. Exact details of the incident are not yet known and CHC is in contact with the Joint Rescue Coordination Center. CHC has also mobilised its emergency response team and next of kin organisation.
Out of respect for passengers and crewmembers, all flights with the aircraft type H225/EC225 have been stopped in the Norwegian sector. Flights with other aircrafts are temporarily halted, and will continuously be evaluated.
Statoil Norway has also opened a next of kin hotline: 800 500 20 and further details will be released when more information becomes available.
Local press contact:
Claus Sonberg, ph + 47 924 62 393 for Norwegian media
Louise Nicolson, ph + 44 7515 881474
CHC press contact
1.214.262.7426
[email protected]
Airbus Helicopters, April 30, 2016 - Airbus Helicopters regrets to confirm that a H225 operated by CHC was involved in a fatal accident off the coast of Norway near Turoey outside Bergen on Friday 29th April.
Preliminary information obtained indicates that the helicopter was flying from Gullfaks B oil platform and was carrying a crew of 2 people plus 11 passengers from Statoil ASA. Latest reports state that 11 people have died and two are missing.
Airbus Helicopters and all of its staff are deeply affected by this tragic accident. We share the pain of the families, friends and colleagues of the victims.
At this point in the investigation, we do not have any information that allows us to understand the causes of the accident that involved the aircraft’s rotor being detached, nor to make any links to events that have occurred previously.
Airbus Helicopters is participating in the on-going investigation and two technical experts are currently on their way to Norway to provide their assistance to the local authorities. In the frame of the investigation, information related to the background of the aircraft is being gathered. The preliminary elements of the inquiry should become available in the coming days.
Under these tragic circumstances, and until these elements are available, we are allied with the decision taken to put all commercial EC225LP passenger flights on hold.
Airbus Helicopters, May 1, 2016 - Considering the additional information gathered during the last 48 hours, Airbus Helicopters’ decision, at this stage, is to not suspend flights of any nature for the EC225LP.
However, out of respect for all those affected by the accident, Airbus Helicopters continues to stand by the decision taken by the Norwegian and UK authorities to put commercial EC225LP passenger flights on hold in Norway and in the UK.
As investigations are progressing, Airbus Helicopters intends to provide an update in the coming days.
Accident Investigation Board of Norway (AIBN), May 1, 2016 - The Accident Investigation Board Norway arrived at the accident site on Turøy in Hordaland Friday evening.
Helicopter wreckage was retrieved from land and the sea bottom Saturday and was then transferred to Haakonsvern naval base (Bergen) by ship. The combined Flight Data and Cockpit Voice Recorder was retrieved from the wreckage Friday night. The unit was taken to AAIB in England where the process of downloading data has started.
Representatives from the French BEA and British AAIB joined the Norwegian investigation team on the accident site Saturday. BEAs specialists are to join the investigation due to the French helicopter manufacturer. Experts from the helicopter and motor manufacturer supports the BEA. The AAIB is joining the investigation because of their recent experience on the helicopter type and offshore operations.
It is difficult to determine an exact timetable for the work ahead but the AIBN team is working as fast as possible to find, if any, safety critical issues as soon as possible. To ensure that important technical findings are communicated to the authorities, both the European Aviation Safety Agency (EASA) and the Norwegian Civil Aviation Agency are invited to join the investigation. Any critical safety information will be communicated. Completing a full investigation including all the factors leading up to the accident will take time, experience suggests at least twelve months.
Today, Sunday, the work continues with search for more parts of the helicopter wreckage both at sea and on land. At the same time, the main wreckage and the large components are brought to Haakonsvern (Bergen) for further investigation.
The data from the recorder, together with an analysis of the accident site and wreckage components, may give knowledge about what happened at the time of the accident and possibly at the time prior to the accident.
Accident Investigation Board of Norway (AIBN), May 2, 2016 - The process of retrieving data from the combined FDR and CRV is completed. The data is of good quality and is sent back to Norway for analysis.
The AAIB has provided their expertise quickly, and ensured that this essential information was secured and handled in the best possible way.
Airbus Helicopters, May 3, 2016 - Airbus Helicopters welcomes the announcement made by the Accident Investigation Board Norway (AIBN) today.
The investigation will now solely be focused on potential root causes of a technical failure, such as design, production, and/or maintenance.
Airbus Helicopters continues to provide its full support to the AIBN investigation.
At this stage and based on the latest information, preliminary inspection of the main gearbox vertical shaft shows no link with the 2012 ditching events.
In addition to the SIN 3031-S-00 and based on the on-going root cause analysis process, precautionary measures are requested:
- An airworthiness directive has been issued requesting measures newly defined in the EASB 53A058 and additional one-off maintenance checks.
- The EASB 53A058 requests the verification of the correct installation of all MGB suspension bar attachments for the EC225LP. Similar measures will be published shortly for the EC725AP in a specific ASB.
European Aviation Safety Agency (EASA), May 3, 2016 - EASA issued an Emergency Airworthiness Directive (AD), following the tragic accident which occurred in Norway on 29 April 2016 to an Airbus Helicopters EC 225 helicopter.
The partial information available so far indicate an in-flight separation of the main rotor from the main gearbox (MGB); an investigation is on-going to identify the root cause of the accident.
EASA AD requires, as a precautionary measure, to perform before next flight certain inspections on the fleet of EC 225 helicopters, and to report any discrepancy to both EASA and Airbus Helicopters.
This AD must be considered an interim action, further mandatory action may follow owing to investigation progress.
View AD 2016-0089-E : Main Rotor Drive(s) – Inspection
CHC Helicopter, May 3, 2016 - Following Friday’s tragic accident involving an EC 225, CHC immediately put all EC 225 flights temporarily on hold with the exception of those aircraft dedicated to life-saving search-and-rescue missions.
Based on the information available to-date, the Accident Investigation Branch Norway (AIBN) has stated that the EC225 LP helicopter suffered in-flight separation of the main rotor hub from the main gearbox (MGB); the root cause has yet to be identified. As a precautionary measure, and while investigations are ongoing, Airbus Helicopters has issued an Emergency Airworthiness Service Bulletin (EASB) 553-A-058, which calls for checks on the installation of the suspension bars.
Subsequently EASA has issued Emergency Airworthiness Directive (EAD) 2016-0089. The EAD mirrors the requirements of the EASB while additionally requiring checks on the main gearbox chip detector and the oil filter for contamination. It also requires the verification of HUMS data. The EAD is considered to be an interim action and further mandatory action may follow.
Airbus Helicopters has since updated their original EASB and have today (Wednesday May 4) issued a Revision 1 to EASB 553-A-058 which effectively mirrors the additional requirements of the EAD.
CHC is complying fully with the requirements of both the EASBs and EAD in addition to any ongoing commercial operational limitations laid down by Regulatory Authorities.
While CHC recognises the additional assurances provided by the EASBs and EAD, we consider continuing to place all EC225 commercial flights around the world on hold to be the most prudent course of action.
CHC remains focused on safely delivering as much capacity as possible using available resources
Accident Investigation Board of Norway (AIBN), May 4, 2016 - The European Aviation Safety Agency EASA published late Tuesday May 3rd an emergency airworthiness directive (AD) concerning the helicopter type involved in the accident at Turøy 29 April. CAA-N has reviewed the content of this directive and has decided to maintain the flight operation stop for helicopter type Airbus EC225LP.
CAA-N has been working intensely with follow up of the accident since the first report came. Shortly after the accident, the CAA-N published a safety directive to stop flights with helicopter type EC225LP. British aviation authorities issued the same restrictions to their operators.
The EASA airworthiness directive published late May 3 entered immediately into force. The directive establishes specific technical inspections to be carried out before the first flight of EC 225 LP after the effectuation of the directive.
CAA-N has considered the directive and has concluded to maintain the temporary flight operation stop for Norwegian helicopters Airbus EC225LP.
The cause of the accident at Turøy is still unknown. Our focus is therefore to ensure that the underlying cause of the accident is found, we are therefore working in close relationship the Accident Investigation Board, British aviation authorities, EASA and other key parties.
Accident Investigation Board of Norway (AIBN), May 11, 2016 - Following the tragic Norwegian Super Puma helicopter accident on Friday 29 April, the UK and Norwegian Civil Aviation Authorities have been collaborating very closely and are united in their approach.
Shortly after the accident, both organisations introduced restrictions to the Airbus EC225LP helicopter to prevent operators using it for commercial flights. Both organisations have now also agreed to extend the scope of the restriction to include the AS332L2 Super Puma helicopter until further information is available. The decision to extend the restriction is based on the close similarities between the two types of helicopter and neither helicopter can be used by either UK or Norwegian operators for commercial flights.
The restrictions do not apply to search and rescue flights.
The accident remains under investigation by the Norwegian authorities and we remain in close contact with all offshore helicopter operators to continue to assess the situation.
Accident Investigation Board of Norway (AIBN), May 13, 2016 - Update on the progress of the investigation : Preliminary report May 13, 2016
Accident Investigation Board of Norway (AIBN), May 27, 2016 - 29 April 2016 the Main Rotor Head (MRH) and mast suddenly detached from an Airbus Helicopters H225 enroute from Gullfaks B to Bergen Airport Flesland. The helicopter impacted on a small island east of Turøy. All 13 people on board perished.
AIBN is now performing detailed examinations of particular components of the helicopter. The examinations are performed in Norway, England and France. The organized search for parts on land and in the sea is temporarily paused. However, important components are still missing, and the AIBN will likely resume the search in June.
The first preliminary report was published on 13 May 2016. An updated preliminary report issued on 27 May 2016 : At this stage, the AIBN can confirm that the scenarios under consideration include failure of epicyclic module, suspension bar (lift strut) attachment and MGB conical housing.
European Aviation Safety Agency (EASA), June 2, 2016 - Emergency Airworthiness Directive 2016-0104-E which prohibits any flights of AS332L2 and EC225 helicopters with the exception of a single flight without passengers to ferry such a helicopter to a maintenance base.
Accident Investigation Board of Norway (AIBN), June 28, 2016 - At this stage of the investigation, the AIBN finds that the accident most likely was a result of a fatigue fracture in one of the eight second stage planet gears. It appears that the fracture has propagated in a manner which is unlikely to become detected by existing mandatory or supplementary systems for warning of an imminent failure. What initiated the fracture has not yet been determined.
Accident Investigation Board of Norway (AIBN), Feb 8, 2017 - 29 April 2016 the Main Rotor Head (MRH) and mast suddenly detached from an Airbus Helicopters EC 225 LP enroute from Gullfaks B to Bergen Airport Flesland. The helicopter impacted on a small island east of Turøy. All 13 people on board perished. The investigation has shown that the accident was a result of a fatigue fracture in one of the eight second stage planet gears, with clear similarities to the G-REDL accident off the coast of Scotland in 2009. It appears that the fracture propagated in a manner which was unlikely to be detected by the mandatory or supplementary systems intended for warning of an imminent failure.
The investigation is complex, and has a wide scope. So far, the metallurgical studies have been a major focus. These are efforts to map and understand why fatigue cracks could form and evolve. This work has not yet been completed.
At present time, the primary focus of the AIBN investigation is certification aspects of the main gearbox and the robustness of past and present design requirements. This includes the follow-up on safety recommendations issued by the AAIB in connection with the accident involving G-REDL and continuing airworthiness of the gearbox. This work requires good collaboration with the responsible entities, primarily the helicopter manufacturer and the European Aviation Safety Authority (EASA).
The scope and complexity of the investigation means that it is not feasible to estimate a completion date for the final report. The investigation continues with the same high activity. Aviation authorities in Norway and Europe are continually updated about the investigation.
The AIBN intends to issue a new preliminary report on 29 April 2017, unless there are significant new discoveries necessitating an interim report in the meantime.
Accident Investigation Board of Norway (AIBN), Feb 23, 2017 - At Thursday 23 February, the Norwegian Naval Diving School found a vital missing part in connection with the ongoing investigation.
The epicyclic gear 2nd stage planet gear carrier was found in the sea between the area of the main rotor separation and the crash site. The carrier will be subject to further investigations.
Accident Investigation Board of Norway (AIBN), July 2018 - The investigation has shown that the combination of material properties, surface treatment, design, operational loading environment and debris gave rise to a failure mode which was not previously anticipated or assessed.
There are no connections between the crew handling and the accident. Nor is there any evidence indicating that maintenance actions by the helicopter operator have contributed to this accident. The failure developed in a manner which was unlikely to be detected by the maintenance procedures and the monitoring systems fitted to LN-OJF at the time of the accident.
From this investigation there are significant lessons to be learned related to gearbox design, safety assessment, fatigue evaluation, condition monitoring, certification requirements and continued airworthiness of the AS 332 L2 and the EC 225 LP helicopters, which also could be valid for other helicopter types.
Based on this investigation, the AIBN issues 12 safety recommendations. July 2018 Report
EC225LP LN-OJF ( Helikopter Service )
See also |
Super Puma in
Helikopter Service Eurocopter EC225LP
Eurocopter AS332L2 Super Puma
Helicopters Accident Reports Bristow Statement Regarding Norway EC225LP Accident
CHC Group Files for Bankruptcy Protection
Statoil to Investigate Norwegian Helicopter Crash
Norwegian Accident Statoil’s Report
EASA Lifts Temporary Suspension of Super Puma
UK and Norway to Clear Restrictions for Super Puma
