Canadian Coast Guard Helicopter Accident: CFIT, Survivability and More
Canadian Coast Guard Helicopter Accident: CFIT, Survivability and More A fatal Arctic Controlled Flight Into Terrain (CFIT) accident to a Canadian Coast Guard (CCG) helicopter highlights a host of safety lessons, including: Low level operation with varying visual clues Compliance with approved maintenance data Survivability Alerting / Flight following Search and Rescue Data recorders Regulatory oversight The Accident The Transportation Safety Board of Canada (TSB) has recently issued their report into the accident to CCG Bo105S CDN-BS-4 C-GCFU in the M’Clure Strait, Northwest Territories on 9 September 2013. The aircraft was one of a fleet CCG use in support of various tasks and operated by Transport Canada, Aircraft Services Directorate (TC ASD). The CCG Bo105s are currently being replaced by Bell 429 under the CCG Fleet Renewal Plan. At 1638 local time, the helicopter departed from CCG Ship Amundsen for an ice measurement and reconnaissance flight. The ship was chartered at the time by ArcticNet in support of an 82-day scientific mission. The pilot was accompanied by the ship’s master and a scientist. Ice measurement requires low level flying. The TSB report that one hour later, at 1738:14, the pilot: …called the CCGS Amundsen to report that its estimated time of arrival (ETA) was in 10 minutes. At that time, the helicopter was in descent at approximately 390 feet. That was the last recorded message from the pilot. The helicopter continued its descent toward the survey altitude and levelled off at 36 feet at 1739:19, while eastbound. For a period of 3 minutes and 30 seconds, the helicopter maintained an altitude varying between 23 and 39 feet. It then made a slow descent for 13 seconds before colliding with water at 1743:02. The 3 occupants evacuated the helicopter before it sank… Upon noticing the helicopter had not arrived: At 1805, the helicopter’s position was checked on the flight following system, which displayed it as being 3.2 nautical miles from the vessel. At 1818, the Amundsen’s crew attempted several times to communicate with the helicopter without success and soon after proceeded to the helicopter’s last position. Debris was spotted and the three occupants were recovered [between 1854 and 1907]. None survived. The helicopter sank in 458 metres of water and was recovered 16 days later. The Safety Investigation – Low Level Operation and Visual Clues The aircraft was operating at low level (20-40ft typically), mostly over ice. Recovered video and still images showed that the ” visual cues and light levels varied considerably during the flight”. Shortly before the accident the helicopter fly over an area of open water, approximately 2.3 nm wide. …the winds were reported as light. Under such wind conditions, the smooth water surface presents a uniform appearance from above, somewhat like a mirror. This would have resulted in a significant reduction in visual cues available to judge height. The loss of references in the near visual field would have required the pilot to increase the scan of other available cues (distant visual field and instruments) in order to detect any change in altitude. Given the low altitude of the flight, this transition would have needed to be very quick, as a momentary loss of orientation could have resulted in contact with the surface. In addition, the dark overcast sky ahead would no longer have provided the distinct line of horizon against the water that would have been present when flying over the ice surface. Therefore, a pitch attitude change would have been difficult to recognize. The helicopter was flown above...
read moreUK OHSAG Oct 2015 Minutes
UK Offshore Helicopter Safety Action Group (OHSAG) October 2015 Minutes The UK Civil Aviation Authority (CAA) has just published the minutes of the 16 October 2015 meeting of the Offshore Helicopter Safety Action Group (OHSAG). This is the third and last of the year (compared to six in 2014), postponed from July 2015. The OHSAG was formed as a result of the ‘Civil Aviation Authority Safety Review of Offshore Public Transport Helicopter Operations in Support of the Exploitation of Oil and Gas’ (CAP1145). Among the items of note: An action regarding oversight of foreign helicopters operators in the UK from the January 2015 meeting remains open and two further actions on cooperative oversight and the risk of consistent application of UK CAA Safety Directives were raised. Further refinement and verification of the bow tie on Normally Unattended Installation (NUI) firefighting protection is underway (a topic we discussed in July 2015) . The proposed NUI policy is “centred on single engine failure accountability (i.e. in the case of a single engine failure on takeoff/approach, demonstrable clearances from deck edge and obstacles/water by 15 and 35 feet, respectively)”. The implementation date for new NUI firefighting protection policy will be 1 May 2016. The Helideck Certification Agency (HCA) will be asked to reference the resulting NUI criteria (“PC1/PC2e and/or crash resistant/fire fighting system”) on NUI helideck plates. It was noted that CAP437 Appendix D, on legacy NUI helideck firefighting provision, would be withdrawn at the next revision of CAP437, but that the 2011 UK CAA letter, contained within it, will remain valid. It was reported that ICAO is to introduce the terms Permanently Attended Installation (PAI) and Not Permanently Attended Installation (NPAI) into the next revision of ICAO Annex 14 Volume II Heliports, which is anticipated to be published in 2016. The UK CAA proposed an activity to classify NUI helidecks based on the quality of the surrounding visual environment when on approach/takeoff at night. However it was also suggested that many NUI owners/operators were generally “not inclined” to invest to comply with the new H and circle lighting requirements, which will effectively mean the end of night operations to those helidecks in 2018. The UK CAA consultation on helideck inspections (a topic we discussed in July 2015) was not debated. The CAA had however issued the following statement on 5 October 2015: “The CAA received twenty responses from the consultation. These responses are being used to assist in the determination of the next steps to address CAP 1145 Action item A13”. In July 2014 the House of Commons Transport Committee recommended that: “The CAA must undertake a joint review with its Norwegian counterparts to uncover why more occurrences are reported in Norway, despite its smaller fleet, and publish its findings within 12 months.” The resulting CAA report is still in draft. It was said that: “All agreed that the report was informative, however it was noted that there continued to be a difference between the numbers of reports and that further work was required to identify where the differences were.” The provision of “high fidelity” EBS training remains an issue and two further actions were raised. In Any Other Business, it was agreed that communication from oil and gas customers “needs to improve”, with a suggestion that it is currently mainly “tactical”. It was also agreed that clarification of the roles and responsibilities of various groups was required. Neither resulted in a formal action. The next CAP1145...
read moreSo You Think The GOM is Non-Hostile?
So You Think The Gulf of Mexico (GOM) is Non-Hostile? The Gulf of Mexico (GOM), off the coast of Mississippi, Louisiana and Texas in particular, remains a busy area for offshore helicopter operations with over 2 million passengers carried and nearly 300,000 flying hours last year (see our article: Helicopter Ops and Safety – Gulf Of Mexico 2014). It is a sea area generally thought as non-hostile, i.e. where: A safe forced landing can be accomplished [i.e. a controllable aircraft can make a ditching and escape is possible]; and The helicopter occupants can be protected from the elements; and Search and rescue response/capability is provided consistent with the anticipated exposure; Indeed for the vast majority of the time the GOM does meet the definition of non-hostile. But very occasionally not… While most observers would expect operations in the immediate vicinity of seasonal hurricanes to affect survivability, winter can do too, particularly if survivors are not able to board a life raft and Search and Rescue (SAR) is not prompt, as demonstrated by the US National Transportation Safety Board (NTSB) report on the loss a Bell 206L4, N180AL, owned and operated by Rotorcraft Leasing Company (RLC) on 11 December 2008. The Accident The pilot and four passengers on-board died after the helicopter impacted the sea approximately 8 minutes after departing Sabine Pass, Texas en route to a platform in the West Cameron 157 block of the GOM. According to the NTSB: The wreckage was located 2 miles offshore in 13 to 15 feet of water, along the helicopter’s route of flight. Damage was consistent with controlled flight into the water. The fuselage was broken into three pieces and the skids (on which were mounted floats and external liferafts) were broken off, suggesting a relatively high speed impact, not a controlled ditching. They go on to say: A cold front had just passed through the area several hours prior to the accident. The Aviation Weather Center…0500… forecast for coastal waters, including the accident helicopter’s route of flight, predicted scattered to broken clouds at 1,000 feet, broken clouds at 2,500 feet, with clouds tops at 5,000 feet. The surface winds were forecast to be out of the northwest at 20 to 25 knots. Occasional broken clouds at 700 feet with visibility three to five miles in rain and mist were forecast. The National Weather Service also had a full series of Airman’s Meteorological Information (AIRMET) current for the area. AIRMET Zulu for moderate icing conditions from the freezing level to 20,000 feet, AIRMET Tango for potential moderate turbulence below 12,000 feet, and AIRMET Sierra for instrument flight rules conditions with ceilings below 1,000 feet and/or visibility below three statute miles in precipitation and mist. The air temperature was recorded at 34 degrees Fahrenheit [1 degree Centigrade] and the water temperature was recorded at 64 degrees Fahrenheit [17 degrees Centigrade]. The pilot held a commercial certificate and an instrument rating; however, he was not approved for instrument flight under Part 135 and was not current. There was no record to indicate that the pilot had obtained a formal weather briefing from a recorded source. According to RLC, other flights in the area had been grounded or delayed due to the passing weather. The NSTB concluded the probable cause of the Controlled Flight into the Terrain (CFIT) was (rather unhelpfully): The pilot’s failure to maintain clearance from the water....
read moreBack to the Future: Error Management
Back to the Future: Error Management A year ago we published our article James Reason’s 12 Principles of Error Management. It set out set out the 12 systemic human factors centric principles of error management that James Reason, Professor Emeritus, University of Manchester defined in his book Managing Maintenance Error: A Practical Guide (co-written with Alan Hobbs and published in 2003). Recently we spotted a photograph of some text in a Tweet. It is from Reason’s earlier 1997 classic Managing the Risks of Organizational Accidents and was a timely reminder: While mention of TQM looks rather dated now, sadly we do wonder how far we have collectively moved as an industry since then: How many organisations still await occurrence or hazard reports from the front-line rather than conducting active oversight or encouraging safety improvement action? How many organisations spend more time analysing individual behaviour after an occurrence to determine culpability than analysing the factors that affect individual performance before an occurrence? We certainly see regular accidents reports that suggest we can do better: Fatal $16 Million Maintenance Errors Misassembled Anti-Torque Pedals Cause EC135 Accident The Missing Igniters: Fatigue & Management of Change Shortcomings A319 Double Cowling Loss and Fire – AAIB Report USAF RC-135V Rivet Joint Oxygen Fire Inadequately Secured Cargo Caused B747F Crash at Bagram, Afghanistan BA Changes Briefings, Simulator Training and Chart Provider After B747 Accident Gulfstream G-IV Take Off Accident & Human Factors Fatal G-IV Runway Excursion Accident in France – Lessons ‘Procedural Drift’: Lynx CFIT in Afghanistan Fatal Night-time UK AW139 Accident Highlights Business Aviation Safety Lessons Fatal Helicopter / Crane Collision – London Jan 2013 Misloading Caused Fatal 2013 DHC-3 Accident Metro III Low-energy Rejected Landing and CFIT Operator & FAA Shortcomings in Alaskan B1900 Accident Culture + Non Compliance + Mechanical Failures = DC3 Accident Mid Air Collision Typhoon & Learjet 35 Metro-North: Organisational Accidents DuPont Reputational Explosion Shell Moerdijk Explosion: “Failure to Learn” Further, as a society, we still see human error being defined as a cause: Saarbrücken flight: Human error determined as cause of accident Two workers quizzed over ‘human error ‘ in Alton Towers horror U.S. general: Human error led to Doctors Without Borders strike Of course we can take heart that many practitioners are making amazing strides in applying Reason’s 12 Principles, enhancing their organisation’s safety culture and looking at other ways to enhance human performance as we discussed here: Maintenance Human Factors: The Next Generation Aircraft Maintenance: Going for Gold? How To Develop Your Organisation’s Safety Culture The Power of Safety Leadership A follow up to the original book, entitled Organizational Accidents Revisited, is due to be published by Ashgate in January 2016 on the topic of what it abbreviates to ‘orgax’. It is reported that: Where the 1997 book focused largely upon the systemic factors underlying organizational accidents, this complementary follow-up goes beyond this to examine what can be done to improve the ‘error wisdom’ and risk awareness of those on the spot; they are often the last line of defence and so have the power to halt the accident trajectory before it can cause damage. The book concludes by advocating that system safety should require the integration of systemic factors (collective mindfulness) with individual mental skills (personal mindfulness). Contents: Introduction. Part 1 Refreshers: The ‘anatomy’ of an organizational accident; Error-enforcing conditions. Part 2 Additions Since 1997: Safety management systems; Resident pathogens; Ten case studies of organizational accidents;...
read moreBell 407 Power Loss GOM Ditching: NTSB
Bell 407 Power Loss GOM Ditching: NTSB (RLC B407 N373RL) The US National Transportation Safety Board (NTSB) has reported on the ditching of a Bell 407 offshore helicopter in the Gulf Of Mexico (GOM) on 11 November 2014. The aircraft, N373RL operated by Rotorcraft Leasing Company (RLC), ditched following a partial power loss shortly after take off from an installation in the Viosca Knoll 989 (VK 989) offshore block. The pilot and three passengers were uninjured. The helicopter reportedly sustained no damage during the ditching itself. It is not clear if it was recovered undamaged but it has re-entered service since. The Accident The NTSB say: …the pilot reported that approximately 30 seconds after takeoff at about 400 feet above sea level, a series of compressor stalls and engine surges began. The pilot adjusted the collective pitch and began a slow decent. After lowering the engine power, the surges and stalls ceased and the pilot’s plan, at this point, was to try to attempt to fly the helicopter back to VK 989. At approximately 250 feet – 300 feet, the pilot began increasing the collective to regain some power, but the engine surges and stalls reoccurred. The pilot reported hearing the low RPM horn and when he observed the rotor RPM gauge (Nr), the Nr was about 90 percent and the power turbine gauge (N2) indicated it was running high; at or near redline. At this point, the pilot made the decision to land the helicopter in the water in the Gulf of Mexico. He fully lowered the collective to salvage the RPM. The engine was still surging at flat pitch so he rolled the throttle to idle and entered an autorotation. The pilot prepared the passengers for the landing and radioed a mayday notification to the operator’s flight following station. He then activated the float inflation handle, pressed the aircraft quick position button, flared the helicopter, and landed on the water. The pilot estimated from the time of the initial compressor stall to water contact was approximately 15 to 30 seconds. The helicopter did not capsize (although sea conditions are not noted) and the: …pilot subsequently deployed the life rafts and got a verbal response from all the passengers that they were “ok.” He directed the passengers to collect their belongings and a first aid kit in case it was needed. They got into the life raft on the left hand side of the helicopter. The pilot boarded the right hand life raft. It is not clear what ‘belongings’ were taken into the life raft or if that odd instruction is part of the operator’s procedures. According to the operator’s report: The Pilot called RLC Operations on the sat phone to let them know his position and that they were all OK. The Pilot observed a fishing boat was making its way to his location from the [Stone Energy] Pompano [platform] about 1.5 miles away. As the boat arrived the Pilot asked the left front passenger to tell the boat to keep their distance for the moment so they don’t make contact with any of the aircraft’s floatation equipment… The Emergency Locator Transmitter (ELT) did not activate. The Investigation Under the supervision of the NTSB investigator-in-charge, the incident [250-C47B] engine was examined at Rolls-Royce… The examination revealed that the engine was shipped without its ECU...
read moreANSV Highlight Procedures & HF After ATR72 Landing Accident
ANSV Highlight Procedures & HF After ATR72 Landing Accident Italy’s Agenzia Nazionale per la Sicurezza del Volo (ANSV) has released their investigation report (in Italian) on a 2013 ATR-72 night landing accident. The Accident On 2 February 2013, ATR-72-212A (marketed as the 72-500) YR-ATS, sustained substantial damage landing at Roma-Fiumicino Airport, Italy. Of the 50 occupants, seven sustained minor injuries. The aircraft was operated by Romanian operator Carpatair on behalf of Alitalia under an ACMI (aircraft, crew maintenance & insurance) wet lease contract. Air Traffic had reported the winds at 22 knots gusting to 37 knots from 250 degrees and issued clearance to land on runway 16L. The Captain (58, ATPL, 18,522 hours total, 3,351 hours on type and the airline’s Chief Pilot), the Pilot Flying, advised he wanted to maintain an approach speed of 130 KIAS. The First Officer (25, CPL, 624 hours total, 15 hours on type plus 36 hours simulator time), the Pilot Monitoring, agreed. The landing gear was extended and 30 degrees flaps selected. The approach was stable as the aircraft descended through 1000 feet AGL, with the speed being around 130 KIAS fluctuating +/- 10 knots. After the autopilot was disconnected an airspeed of about 125 KIAS was maintained. The aircraft touched down 2.6 degrees nose down, nose gear first and bounced. While the crew recognised this, neither pilot called for a go-around. The Captain provided nose down inputs causing the aircraft to sharply touch down a second time on the nose gear, which collapsed, although the aircraft now bounced a third time. The pilots now provided conflicting control inputs. The Captain making further nose down inputs and the First Officer nose up inputs (triggering the interlock to separate left and right flying controls). Consequently the aircraft rolled slightly left and touched down heavily on the left main gear, damaging it, bouncing again with a right bank angle of about 10 degrees, touching down a fifth time causing the collapse of the right main gear. The aircraft slid for 400m, yawing around 170 degrees before coming to a stop. Even though the wreckage was 400m in front of an airport fire station it took the airport fire service ten minutes of searching in the dark to find the accident site because they were apparently not familiar with the taxiway designation passed by Air Traffic. The Safety Investigation The ANSV concluded that no technical factors contributed to the accident. The ANSV believe wind data transmitted to the crew exceeded the 35 knots demonstrated aircraft crosswind capability of the ATR-72 (though the crosswind gust level component was in fact marginally less) and state the Captain remained confident that he could manage a safe landing nonetheless. This confidence was reinforced as prior aircraft had managed to land safely. The ANSV conclude that in the light of the weather information available, the landing should have been aborted. The Descent Checklist was read and properly executed by the First Officer according to the ANSV, however, upon the item Landing Briefing the Captain incorrectly stated that this had already been done. The ANSV highlight that this briefing would have been crucial in identifying limits of the approach, reviewed performance data such as approach speed (Vapp), as well as establishing the criteria and procedure for a missed approach. The ANSV note that the omission of the landing brief led to the acceptance of a Vapp of 130 KIAS and prevented a discussion between the pilots whether landing in Rome or a diversion to the alternate was advisable. The...
read morePDG Helicopters Commence UK & Eire Lighthouse Support Contract
PDG Helicopters Commence UK & Eire Lighthouse Support Contract On 1 December 2015 PDG Helicopters commenced a £13mn helicopter support contract for the three UK and Eire General Lighthouse Authorities (GLAs): The Commissioners of Northern Lighthouses, known as the Northern Lighthouse Board (Scotland and the Isle of Man) whose history goes back to 1768 The Corporation of Trinity House, known as Trinity House (England, Wales, Channel Islands and Gibraltar), the oldest of the three, granted a royal charter in 1514 The Commissioners of Irish Lights, known as Irish Lights (the Republic of Ireland and Northern Ireland) dating to only(!) 1786 Up to 30 November 2015 the GLAs had three separate contracts: Trinity House: MD902 – Specialist Aviation Services NLB: EC135 – Bond Air Services (part of Babcock International) Irish Lights: EC135 – Irish Helicopters (which is owned by PDG Helicopters) PDG took delivery of a new Airbus Helicopters EC135T2+ G-GLAA, configured for lighthouse support, at Helitech in London on 6 October 2015 for the 7 year contract (with three optional one year extensions). The contract supports maritime navigation aids, mostly in remote locations, includes considerable HESLO / underslung load work (the requirement was for an aircraft that could move individual loads >500kg over 50nm to support construction projects), operation with GLA’s fleet of ships (four are ‘helicopter capable’), as well as passenger movements. The contract is expected to involve around 1000 flying hours per annum. This contract is a good example of three customers, with common specialist requirements, working together to place a cost effective long term contract. Some reports suggest this arrangement could save nearly £8mn. Aerossurance discussed the award of the contract in more detail back in October 2014. The UK Civil Aviation Authority (UK CAA) issued Safety Directive SD-2015/004, on 30 November 2015 which expands their earlier Offshore Operational Directive to include lighthouse / marine light support (as well as addressing medically incapacitated passengers). UPDATE 9 December 2015: This SD was replaced by SD-2015/005 on 9 December 2015 because the CAA had neglected to amend the definition of ‘offshore locations’ to actually include those related to marine lights. UPDATE 20 January 2016: A short video of PDG longline work. UPDATE 12 May 2020: Coronavirus: Keeping lighthouses working during the lockdown If you need specialist advice on efficient and safe contracting for specialist aviation tasks (such as HESLO or HHO) and assurance of your aviation contractors, contact aviation consultancy Aerossurance at enquiries@aerossurance.com Follow us on LinkedIn and on Twitter @Aerossurance for our latest...
read moreS-92A Emergency Landing: MGB Oil Checklist Recommendation
S-92A Emergency Landing: MGB Oil Checklist Recommendation Earlier this month the Norwegian Accident Investigation Board (AIBN) issued their report into an emergency landing of Sikorsky S-92A LN-ONW, operated by Bristow Norway on 4 October 2013. The crew almost ditched due to false warnings created by a single tripped circuit breaker. The Incident The S-92A was returning from the BP Valhall offshore installation in the North Sea to Stavanger Sola airport, after abandoning landing on the Valhall due to poor weather. En route to Sola, the crew received MGB PUMP 1 FAIL and MGB PUMP 2 FAIL yellow cautions. According to the AIBN: …the oil pressure had decreased from a normal value of approx. 58 psi to 49, while oil temperature was rising. This was considered a confirmation that something had happened to the main gear box. However, the emergency checklists did not provide an answer to what had happened, or what action to take. In retrospect, the commander has described this as highly frustrating. The AIBN report that: The crew considered that it was too risky to continue toward land, and chose to make an emergency landing at the decommissioned [production platform] Yme. …the crew became aware of three additional yellow cautions for MGB OIL HOT, MGB OIL PRES and MGB MAN COOL. These cautions did not provide any further information to understand the situation. The possibility that there could be a critical failure in the main gear box, also made the crew consider a possible emergency landing at sea before the helicopter reached Yme. Wind and wave height were estimated at 40 kt and 7 to 8 m respectively [wave height being beyond the helicopter’s ditching certification]. As long as no red warning lights showed up, and oil pressure indicated above the 47 psi minimum requirement, they decided to continue towards Yme. Accordingly, they interpreted the situation as “Land as soon as possible” and not “Land immediately”. The crew seriously considered landing on the hatch covers of a passing ship, but due to the sea state decided to continue to the Yme. The crew noted two obstructions on the closed helideck, and were surprised to find these were two 3.5m tall marine transponders. However the crew were able to make a safe landing in the confined space. When the helicopter landed, the first officer read that the oil temperature on the main gear box was 152 °C. There was no damages during the emergency landing. The crew and passengers were later picked up by a rescue helicopter and flown ashore. The Safety Investigation The next day, technicians were flown to Yme in order do trouble shooting. Early it became clear that the indications received by the crew could be related to the tripping of the M XMSN OIL WARN circuit breaker. This was confirmed. After a temperature switch (Main Transmission High Temperature Switch, P/N 92351-15808-101) was replaced, and the helicopter had been thoroughly checked by running the engine while on the ground, the helicopter was flown to Sola on Sunday 6 October. The AIBN Comment: The investigation showed that several of the cautions the crew received were false, and were caused by a minor fault in the indication system. The crew became seriously concerned about the indications. Despite uncertainty that arose, the crew handled the situation in a good manner and made operational...
read moreMisassembled Anti-Torque Pedals Cause EC135P1 Accident
Misassembled Anti-Torque Pedals Cause EC135P1 Accident The US National Transportation Safety Board (NTSB) has recently determined that misassembled anti-torque pedals caused an accident to Airbus Helicopters (formerly Eurocopter) EC135P1 N911KB, during a post-maintenance check flight by Metro Aviation at Shreveport, Louisiana on 9 November 2013. The Accident The pilot and two mechanics sustained minor injuries and the helicopter was substantially damaged after the Loss of Control – Inflight (LOC-I) while transiting to a nearby field for a hover test. In their report the NTSB state: The pilot attempted to regain control of the helicopter using the antitorque pedals, but they were ineffective. The pilot reduced engine power and performed an autorotation to the field. The helicopter landed hard and rolled on its right side. The Investigation On examination of the wreckage the NTSB: …found that the antitorque pedals had separated from the antitorque levers. The attachment hardware was not located in the wreckage or the surrounding area. Neither the antitorque pedals nor the lever attachment holes displayed elongation, which is consistent with the hardware bolts not being in place at the time of impact. The NTSB report (emphasis added) that: A review of the helicopter’s log book found an entry dated October 31, 2013, that a mechanic performed the action “disassemble, inspect, and reassemble tail rotor pedals”. According to a statement provided by the company’s director of maintenance, after the accident a search of the area maintenance area was conducted. Near the area where the helicopter was previously repaired, a small parts bag was found tied to the tail rotor control cable that had been replaced. Inside of the bag were bolts similar to the bolts used to secure the anti-torque pedals. Circumstances The aircraft had been undergoing an 800 hour check and a scheduled engine change. Closer examination of the NTSB public docket reveals, in a statement by the facility’s then Director of Maintenance (DoM), that they were under pressure from the operator of the aircraft: The scope of work had originally been slated for a four to six week work schedule, but demand by the using customer dictated that the scope of work be shortened to the minimum time needed to complete only the inspections and any repair as needed to ensure airworthiness of the aircraft. They (the using customer) had requested that this work be completed in 5 days or sooner if possible. I explained this was not possible due to personnel availability, and depth of inspection requirement. Also, personnel shortages: …created a situation where repair station personnel were bouncing back and forth between aircraft undergoing other maintenance activities [and] helping those personnel who were working on this aircraft. This was not ideal and made job continuity difficult. The DoM goes on: I did observe one of the…technicians with the pilot pedal shaft assemblies in his hands shortly after removal performing the required inspection. I quizzed him to ensure he understood the inspection requirement on the pilot pedal shaft and support. He gave me enough information to make me believe he did In fact understand the inspection requirements. The NTSB do not unfortunately appear to have interviewed the technician, reducing the learning opportunity available. NTSB Conclusion The NTSB determines the probable cause to be: The mechanic’s improper installation of the antitorque pedals, which resulted in an in-flight loss of helicopter control. Observations This is a further accident that highlights the need...
read moreNorwegian Survival Suits: Suited for Safety
Norwegian Survival Suits: Suited for Safety The Norwegian Petroleum Safety Agency (PSA), has published a piece on the history of survival suits in Norway in their latest Dialogue magazine. Amusingly their first illustration highlights a hazard unique to early survival suits that we discussed after the 2014 Oil & Gas UK annual aviation seminar, namely cigarette burns, as smoking was still allowed! The article primarily concentrates on developments by Hansen Protection, including the development of the Sea-Air Barents suit, which can be fitted with a compressed air Sea-Air EBS (Emergency Breathing System): Sea-Air Barents Survival Suit (Credit: Hansen Protection) The material of the suit includes tiny capsules filled with microscopic particles of a paraffin wax specially developed by SINTEF. When the wearer’s skin temperature rises above 28ºC, the wax absorbs the body heat and changes from solid to liquid. The latent heat help keeps the wearer is cool in the helicopter cabin on warm days. When immersed in water, he wax releases the stored heat to the wearer as it returns to the solid state. Hansen Protection claim this ensures the wearer’s skin temperature never falls below 15ºC during six hours in a water temperature of about 2ºC. The suit will be used in operations to support the ENI Norge Goliat FPSO in the Barents Sea from Hammerfest. Another article in that issue discusses a collaboration to overcome the challenges of operating in the Barents Sea. Aerossurance has provided aviation support to two of the 16 companies involved in that effort. Background Survival suits are an area currently being examined as part of the European Aviation Safety Agency (EASA) Rule Making Team RMT.0120 that is working on enhancements to helicopter ditching and survivability. A Notice of Proposed Amendment (NPA) is due around the end of 2015. Aerossurance has previously discussed new helicopter survival suits being introduced in Canada, the standardisation of clothing policy in the UK and the introduction of Category A Compressed Air – Emergency Breather System (CA-EBS) the UK. The later two follow the publication of UK Civil Aviation Authority (CAA) ‘Safety Review of Offshore Public Transport Helicopter Operations in Support of the Exploitation of Oil and Gas’ (CAP1145). The article discusses the loss of the floatel Alexander Kielland in 1980 and three helicopter accidents: 9 July 1973 Sikorsky S-61N LN-OQA: Ditched and capsized after loss of tail rotor (4 fatalities, all post impact) – note the PSA incorrectly state this happened in June 1973 23 November 1977 Sikorsky S-61N LN-OSZ: Impacted the water after a main rotor damper failure (12 fatalities including one person who did reportedly escape the aircraft alive) 26 June 1978 Sikorsky S-61N LN-OQS: Impacted the water after a main rotor spindle failure (18 fatalities) All three aircraft were operated by Helikopter Service. The choice of helicopter accidents is interesting. In the first case survival suits would have been a definite advantage. The second case appears to have been a survivable water impact and so a survival suit would have been beneficial to the person who exited the aircraft and may have helped others. In the third accident (with over half of the fatalities), the loss of a main rotor blade in flight would have been non-survivable and so survival suits would have been irrelevant. While operating without survival suits over a hostile sea is inconceivable today, the above accidents also illustrate the inappropriateness of trying to justifying safety improvements on past accidents...
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