FAA Impose Fines After Maintenance Errors – Just Culture?
FAA Impose Fines After Maintenance Errors – Just Culture? The Federal Aviation Administration (FAA) have proposed fining two helicopter emergency medical service (HEMS) operators and one airline a total of $12.4 million for allegedly operating non-compliant aircraft after various maintenance errors. However does this encourage a just, open reporting culture? The Cases In each case it should be noted that the FAA have publically proposed these fines but the organisations can appeal or negotiate for a lower penalty. Firstly, the FAA propose fining Southwest Airlines of Dallas, Texas $12 million, alleging: …that beginning in 2006, Southwest conducted so-called “extreme makeover” alterations to eliminate potential cracking of the aluminum skin on 44 jetliners. The FAA conducted an investigation that included both the airline and its contractor, Aviation Technical Services, Inc., (ATS) of Everett, Wash. Investigators determined that ATS failed to follow proper procedures for replacing the fuselage skins on these aircraft… All of the work was done under the supervision of Southwest Airlines, which was responsible for ensuring that procedures were properly followed. It is interesting that the FAA do not also propose fining the FAA approved Part 145 Repair Station who are alleged to have not followed proper procedures. Southwest returned the jetliners to service and operated them when they were not in compliance with Federal Aviation Regulations, the FAA alleges. The regulatory violations charged involve numerous flights that occurred in 2009 after the FAA put the airline on notice that these aircraft were not in compliance with either FAA Airworthiness Directives or alternate, FAA-approved methods of complying with the directives. Retrospectively Southwest submitted data that allowed the FAA to approve the alternative procedures used. Also: During its investigation, the FAA found that ATS workers applied sealant beneath the new skin panels but did not install fasteners in all of the rivet holes during the timeframe for the sealant to be effective. This could have resulted in gaps between the skin and the surface to which it was being mounted. Such gaps could allow moisture to penetrate the skin and lead to corrosion. As a result of the improper repairs, these airplanes did not comply with Federal Aviation Regulations. The FAA also alleges that ATS personnel failed to follow requirements to properly place these airplanes on jacks and shore them up while the work was being performed. If a plane is shored improperly during skin replacement, the airframe could shift and lead to subsequent problems with the new skin. Corrective maintenance action is only mentioned in the final allegation: …the FAA alleges that Southwest Airlines failed to properly install a ground wire on water drain masts on two of its Boeing 737s in response to an FAA Airworthiness Directive addressing lightning strikes on these components. As a result, the aircraft were not in compliance with Federal Aviation Regulations. The airplanes were each operated on more than 20 passenger flights after Southwest Airlines became aware of the discrepancies but before the airline corrected the problem. These allegations highlight the importance of: Conducting all maintenance in accordance with approved maintenance data Seeking approval for justified alternative data in advance Ensuring that data is referred to and followed Promptly responding when maintenance errors are detached Ensuring maintenance organisations/continuing airworthiness management organisations have effective assurance processes to monitor actual maintenance standards According to Southwest: Having fully resolved the repair issues...
read moreEASA Launch Helicopter Gearbox Lubrication Rule Making
EASA Launch Helicopter Gearbox Lubrication Rule Making The first meeting was held last week of a new European Aviation Safety Agency (EASA) Rule Making Team (RMT.0608) on helicopter gearbox lubrication. The Terms of Reference (ToR) and Group Composition (GC) are here. This activity follows European/US/Canadian dialogue after the loss of Cougar Sikorsky S-92A C-GZCH Flight 491 off Newfoundland, Canada on 12 March 2009 in which 17 people died, although one passenger, Robert Decker, survived. The Canadian Transportation Safety Board (TSB) reported on that accident in 2011. TSB state: On 06 August 2002, Sikorsky carried out its initial certification loss of lubricant test by draining the MGB and using only the remaining residual oil (approximately 1.3 gallons) then continuing operation in accordance with the requirements of AC 29-2C. The purpose of this test, outlined in the test documentation, was to demonstrate that the S-92A transmission could provide, “continued safe operation for a minimum of 30 minutes following a complete loss of lubricating oil in accordance with the requirements of FAR 29.927(c)(1).” … Sikorsky and the FAA expected that, based on the similarities between the S-92A’s MGB and the Sikorsky S-60 [sic: H-60 / S-70] Black Hawk‘s MGB, the S-92A’s MGB would successfully operate for 30 minutes after draining the lubricating oil. The FAA indicated that the initial test was thought to be a low risk test, and Sikorsky scheduled it very late in the overall S-92A certification program. This original S-92A test matched the way other manufacturers conducted such a loss of lubrication test. TSB explain that: EASA indicated that applicants in its jurisdiction normally complied with Part 29.927(c)(1) by draining the MGB and continuing operation with only residual oil. Prior to the S-92A certification validation it had already tested and certified at least four helicopters using this criterion. Aerossurance is aware that Canadian manufacturers also followed the same interpretation as the European manufacturers. Unfortunately with just 1.3 gallons of oil the S-92A MGB: …suffered a catastrophic failure about 11 minutes after the test was started. TSB go on: Following the loss of lubricant test resulting in catastrophic failure, instead of taking steps to redesign the transmission to provide a 30 minute run dry capability [sic: this term is not used in regulation] for the MGB, Sikorsky re-visited the requirements of Part 29.927(c)(1). Relying on guidance from AC 29-2C and the FAA [Federal Aviation Administration] Rotorcraft Directorate, Sikorsky and the FAA concluded that, except for a potential failure of the oil cooler and its exterior plumbing, all other MGB failures leading to a total loss of oil were extremely remote. …the MGB lubrication system was redesigned to incorporate a bypass valve. The loss of lubricant test was repeated on 16 November 2002 with the bypass system installed. This test was carried out by draining oil from a leak in the oil cooler system. The leak was isolated and further oil loss was prevented when the bypass valve was activated. About 4.3 gallons or 40% of the maximum oil quantity remained in the MGB. The S-92 was certified by the FAA on 17 December 2002, one month after the second test and in time to be awarded the prestigious Collier Trophy for “the greatest achievement in aeronautics or astronautics in America” of 2002. Just one day before that certification, another Sikorsky product, an S-61N C-FHHD, was involved in an accident in Canada after a loss of main gear box oil, which should...
read moreOGP Safety Performance Indicators 2013
UPDATE: This article has been reviewed and updated since the publication of OGP’s V1.1 reports adding details that our first edition highlighted were missing. Follow us on LinkedIn for our latest updates. The International Association of Oil & Gas Producers (OGP) has published their annual safety performance review. Earlier 2012 data is here. The OGP members who contribute reported details of 80 fatalities worldwide in 2013 (down from 88 the previous year). Of these 47 were onshore and 33 offshore. The fatal accident rate was 11% lower than 2012 and the Total Recordable Injury Rate was 8% lower. For those interest in aviation safety in the OGP domain: there were 17 fatalities in 2 helicopter accidents, making air transport the category of activity with the highest number of fatalities with 21.% of the total (up from 2.3% in 2012 when there were just 2 aviation fatalities when two crew died when a B212 seismic helicopter crashed on its approach to a landing zone in a forested area of Gabon). The detailed list of fatal events describes: the loss of a Mi-8 of Helicópteros del Pacífico OB-1916-P onshore in Peru in April 2013 with the loss 4 crew and 9 passengers the loss of a CHC AS332L2 G-WNSB and 4 passengers off Sumburgh, Scotland in August 2013 In the case of the Peruvian accident two recommendations are reported: a) hire an aviation specialist to monitor audit findings and b) to replace this family of helicopters. It is also stated that 1.7% of lost work day cases (i.e. 27) are related to air transport (20 offshore and 7 onshore), up from just 0.5% in 2012. In the listing of high potential events are basic details of: A ground collision between a taxying B1900 and a parked ATR42 in Yemen that does not seem to have been reported publically elsewhere The loss of a passenger door from an AS365N helicopter in Tunisia UPDATE November 2014: OGP is now IOGP. For advice on aviation safety & contracting for the oil and gas industry and first hand expertise with the IOGP Aviation Management Guidelines (Publication 390), contact: enquiries@aerossurance.com Follow us on LinkedIn for our latest updates...
read moreEASA Launch Rule Making Team on In-flight Recording for Light Aircraft
EASA Launch Rule Making Team on In-flight Recording for Light Aircraft The European Aviation Safety Agency (EASA) has launched a Rule Making Team (RMT.0271 & 0272 [MDM.073 (a) & (b)]) on in-flight recording for light aircraft. The Terms of Reference (ToR) and Group Composition (GC) are here. By way of definition the ToRs state: …‘in-flight recording’ means recording by an airborne system of data that can be easily used to reconstruct the history of the flight for the purpose of a safety investigation. In-flight recording solutions include, but are not limited to, flight recorders. EASA note that aircraft that aren’t required to carry data recorders include: Aeroplanes <5 700 kg used for commercial air transport (CAT) operations Helicopters <3 175 kg used for CAT Lighter Than Air aircraft used for CAT Light aircraft operated for General Aviation One could argue that this initiative is particularly important now that EASA have issued a notice of proposed amendment on commercial air transport operations at night or in IMC using single-engined turbine aeroplane (NPA2014-18). The likely aircraft types are the Cessna C208 Caravan, Pilatus PC-12 and Socata TBM700/850. Eight safety recommendations have previously been addressed to EASA recommending the introduction of in-flight recording for lighter aircraft (listed below in chronological order of accident date): SPAN-2012-011 Swearingen SA226 registered EC-GDG, 18/02/1998 (accident report); UNKG-2005-101 Bell 206 registered G-BXLI, 22/01/2005 (accident report); FRAN-2009-008 Beech C90 registered F-GVPD, 18/10/2006 (accident report); HUNG-2008-002 Eurocopter EC135 registered HA-ECE, 31/07/2008 (no report online); NETH-2012-001 Pilatus PC12 registered PH-RUL, 16/10/2009 (accident report); FRAN-2013-012 Cessna 208 registered F-OIXZ, 05/09/2010 (accident report); NORW-2012-010 Aerospatiale AS350 registered LN-OXC, 04/07/2011 (accident report); FINL-2014-001 Cessna 206 registered OH-AAA, 08/11/2012 (accident report). Aerossurance has previously reported on recommendations made in other countries (such as Canada). The US National Transportation Safety Board (NTSB) has had wider recorder use on its ‘most wanted list’ too. EASA notes that industry standards for flight recorders for light aircraft are available (e.g. EUROCAE ED155 [Minimum Operational Performance Specification for lightweight flight recording systems] issued in July 2009). In 2006 the UK Civil Aviation Authority (CAA) published a research report on “The Effectiveness of Image Recorder Systems in Accident Investigations (CAP 762). In their conclusions they stated: …the research indicates that image recording systems can, if properly installed and appropriately analysed together with conventional recording systems, provide additional information that would assist in accident investigation. Aerossurance has previously commented on other recorder options that have been successful introduced. EASA also point out that: Other equipment mandated or usually carried on board light aircraft has also some recording capability. Advantage could be taken of this equipment as an alternative solution to a dedicated in-flight recording solution. One example is the Garmin G1000 Flight Data Logging and SD card download capability. The team is tasked with: Assessment of the need for in-flight recording for each combination of aircraft category, aircraft mass or occupancy, and type of operation indicated [above]. This assessment should take into consideration the cost constraints peculiar to light and general aviation; Identification, where in-flight recording is justified, of the recording function(s) needed (flight parameters, or audio, or both); Establishment of a list of in-flight recording solutions that ranges from the cheapest and lightest solution to the conventional crash-protected flight recorder. This list may include alternative solutions, such as using or enhancing airborne equipment designed for other purposes; Proposal of definitions and requirements,...
read moreS-92A Nose Landing Gear Incident – Aberdeen 29 July 2014
S-92A Nose Landing Gear Incident – Aberdeen 29 July 2014 A minor landing gear incident on a CHC Sikorsky S-92A at Aberdeen Airport in Scotland has attracted press interest. The Nose Landing Gear could not be lowered resulting in the need for maintenance intervention while the aircraft was in a low hover with 16 passengers and two crew aboard. Photographs were posted on an oil workers Facebook page. Observations: This neatly demonstrates: The need to be prepared to respond safely to any eventuality Someone will always be prepared to photograph and tweet or Facebook it! One nice positive is that the local press do highlight that the successful efforts of CHC’s maintenance team did get recognised: Users of the social networking site were quick to praise the workers. One commented: “Fair play to the lads that got under and sorted the landing gear! Good effort boys.” On 24 January 2010, a CHC S-92A at Esbjerg in Denmark, OY-HKA suffered a NLG failure. The Danish Havarikommissionen accident investigators explain in their report that the NLG should self centre when unloaded but this can fail to occur if their is too little hydraulic fluid within the strut (due to a leak for example) or the nitrogen pressure is too high. In the Esbjerg incident, which occurred at night, the aircraft landed on a pallet of bags of salt. The investigators say that: As a result of this incident and their investigations, the helicopter manufacturer has changed service procedure in their maintenance manual AMM (Aircraft Maintenance Manual). The operator’s maintenance organization has informed the Havarikommission that they subsequently have reduced service interval from 500 flight hours to 250 flight hours based on the incident. The effectiveness of the actions are suspect following the UK occurrence. The passengers and crew aboard these two S-92As are not the only people to have a helicopter landing gear failure disrupt their arrival. In May 2008 David Cameron, later British Prime Minister, had to jump from a helicopter at Redhill Aerodrome, before the pilot landed on a bed of car tyres. The UK Air Accidents Investigation Branch (AAIB) reported on that incident in 2010. In that case, with an Agusta A109, it is believed that misassembly of the landing gear selector was responsible. UPDATE 9 August 2018: AAIB release their report into another S-92A NLG incident, on G-CHHF of Bristow, 29 January 2018: During a final approach to land at Scatsta the NLG failed to extend despite being recycled and the use of the emergency blowdown system. The crew declared a PAN and the decision was taken for ground crew to lever the NLG down manually. This was successfully carried out and the helicopter landed safely. It was found that the automatic nosewheel self-centring mechanism had not operated, causing the nosewheels to jam the nose leg in its bay. The exact cause of the failure of the NLG to centre the nosewheels during retraction could not be determined. The helicopter manufacturer has investigated six reports of previous events where the NLG was off-centre, jammed in the wheel well and failed to extend either by the primary or secondary means. …low oil or nitrogen charge in the strut results in the self-centring cams not interlocking correctly, allowing the wheels to remain off-centre when the aircraft weight is ‘off-wheels’ prior to retraction. In September 2017 the manufacturer issued a letter...
read moreLiving Near Zero – New Challenges for Air Safety
Living Near Zero – New Challenges for Air Safety Between 17 July 2014 and 24 July 2014 the aviation industry has been rocked by three loses of commercial passenger aircraft and 462 lives: 17 July 2014 Malaysia Airlines Boeing 777-200ER 9M-MRD (flight MH17) overflying Ukraine after what appears to have been a surface to air missile attack (see Aviation Safety Network database entry here). 23 July 2014 TransAsia Airways ATR42 B-22810 (flight GE222) on approach to Magong, Taiwan in poor weather (see the ASN entry here). 24 July 2014 Swiftair MD83 EC-LTV on charter to Air Algerie (flight AH5017) in the cruise over Mali in poor weather (see the ASN entry here). In this article we will separate deliberate violent/terrorist/military actions from ‘accidents’. However, the MH17 loss certainly raises questions about operational route planning, regulation, risk assessment and the value of defensive aids. The International Civil Aviation Organisation (ICAO) will be hosting a special high-level meeting on 29 July 204 with the Directors General of the International Air Transport Association (IATA), Airports Council International (ACI) and the Civil Air Navigation Services Organisation (CANSO). The subject is how to “more effectively mitigate potential risks to civil aviation arising from conflict zones”. Harro Ranter of the Aviation Safety Network has analysed the losses in 2014 to date and July 2014 in particular and produced a historic comparison. Statistically it is not unusual for clustering of accidents, as discussed in a recent BBC article. While no consolations to the bereaved families of the victims of these recent events, with an estimated 36 million commercial flights per annum worldwide, the risk of dying in a commercial airline accident remains remarkably remote. Nearly 20 years ago years ago there was alarm that unless commercial airliner safety improved we would be averaging a airliner accident every week globally, as air traffic increased. Flight International correspondent David Learmount recently looked back at the 1970s and in particular the first half of 1974. He found: …that there had been 25 fatal accidents involving passenger flights in that period… So we’d been at the weekly accident stage before! Of course the 1990s safety performance was itself a product of two decades of hard work reducing the accident rate faster than the increase in total traffic. The fear two decades ago was that traffic would outpace our ability to improve. This triggered a number of safety initiatives (such as the Commercial Air Safety Team, [CAST]), which coupled with increasing understanding of organisational accidents and the introduction of more modern aircraft have allowed improvements to continue. Aerossurance recently discussed data from Airbus that illustrates the improvements with newer technology aircraft. Aerossurance also recently highlighted positive performance in the European Union discussed in the European Aviation Safety Agency’s Annual Safety Review. For the first half of 2014, Learmount points out: …a preliminary estimate of airline fatal accidents in the first six months of 2014 shows six, and the total number of resultant deaths is 267. But those numbers for the first half of 2014 include the missing Malaysia Airlines Boeing 777-200ER flight MH370, which may turn out to have been due to criminal acts and 4 accidents which did not involve passengers. In fact, there was just one confirmed fatal accident with passengers, a Nepal Airlines Viking DHC-6 Twin Otter, which flew into a mountain side in poor visibility killing 18 people (see the Aviation Safety Network database entry here and footage of the accident site here). Bottom...
read moreR44 Oil & Gas Accident – Alcohol, Flight Following, ELTs
R44 Oil & Gas Accident – Alcohol, Flight Following, ELTs The Transportation Safety Board (TSB) have reported on an unusual helicopter accident in Alberta, Canada on 27 January 2013, that has important lessons on pilot supervision, flight following and emergency location. Operator & Pilot Background Robinson R44 C-GOCM was operated by Gemini Helicopters, headquartered at Grande Prairie, Alberta, who operated a fleet of 20 helicopters for charter and to support ‘production services’. ‘Production services’ means providing flying production operatives to tend to dispersed oil wells and pipelines. In April 2013 Gemini Helicopters bought Airborne Energy Solutions from Nabors Canada and saw its fleet expand to 67 aircraft. The new company traded as OpsMobile at the time this article was written. Gemini had previously had a non-fatal R44 accident about a year earlier (C-FGBX). The pilot on the day of the accident was in his mid 30s and TSB reports he had been employed by the Company since May 2011, and had approximately 2200 hours of flying time, with 2100 hours on the R44. Flights on the Afternoon of the Accident Early in the afternoon of 27 January 2013 the helicopter lefts its base at the Horse Facility gas plant camp and made a couple of flights to production facilities then according to the TSB: …then at 1450, the helicopter made an unauthorized flight to a roadside security gate. After 3 approaches, the helicopter landed at 1510. At 1545, the pilot was observed to be staggering and smelling of alcohol. On being questioned, the pilot uttered some derogatory remarks. The pilot and an unauthorized passenger from the security gate then boarded the helicopter. The helicopter departed at 1554 to a compressor site, landing 8 minutes later. The helicopter was left running while work was done at the site by the pilot. It departed at 1611, and was flown low along the Berland River before landing and shutting down at a remote cabin at 1630. Forty-eight minutes later, at 1718, the helicopter lifted off and flew to the location of the security gate, where it made several low passes and turns. The aircraft landed at the gate at 1731, and the passenger disembarked 2 minutes later. The helicopter took off at 1735 and was observed to be flying erratically during departure. It broke up in flight over a wooded area 5 minutes later. The Structural Failure TSB found nothing to indicate airframe failure or system malfunction prior to the in-flight breakup. They considered the main rotor blade damage found was consistent with the pilot manipulating the flight controls such that a main rotor blade struck the right side of the cabin. TSB also note the aircraft was fitted with a bubble window under a Supplemental Type Certificate which introduced a never-exceed speed (VNE) limit of 100 knots. Analysis shows the aircraft was flying at up to 126 knots. Alcohol As mentioned above, witnesses reported seeing the pilot acting in an erratic way and smelling of alcohol, though no apparent attempt was made to intervene. TSB did establish that the evening before, the pilot had left the camp and “to pick up a case of beer”. It is believed he consumed “3 or 4 beers” that evening. TSB were not able to conclusively identify if the pilot consumed any further alcohol that night or on the day of the accident. An empty wine bottle and an empty liquor bottle were found at the cabin,...
read moreTechnology Friend or Foe – Automation in Offshore Helicopter Operations
Technology Friend or Foe – Automation in Offshore Helicopter Operations In London 3-4 July 2014 the Royal Aeronautical Society held a landmark conference on the introduction of automation to offshore helicopters titled: Technology: Friend or Foe? This RAeS conference was triggered by: a CFIT accident on approach to Sumburgh airport in August 2013 (AS332L2 G-WNSB), the issue, a few weeks later, of a Transportation Safety Board (TSB) report into a serious incident where S-92A C-GQCH where the helicopter descended to within 38ft of the sea, the realisation that automation issues were not addressed in detail in the UK Civil Aviation Authority (CAA) North Sea Review, which resulted in the CAP1145 report (the ‘Safety review of offshore public transport helicopter operations in support of the exploitation of oil and gas’). The conference was notable for an impressive range of speakers and a carefully structured programme that set the context of offshore operations, examined key technology, discussed the modern cockpit, operational procedures and finally training & competency. The conference was an ideal opportunity to look back at how automation had been introduced and the critical lessons, including cultural lessons, that need to be learnt. To underscore the importance of the topic, just days after the conference the UK Air Accidents Investigation Branch (AAIB) published their report into a serious incident with EC155 OY-HJJ that suffered a loss of control after departure from a helideck in the North Sea in November 2013. Jim Lyons, who masterminded the conference programme, has produced a detailed summary of the conference. The RAeS Rotorcraft Group are expected to publish a position paper on the topic. See also our article: Commanders: Flying or Monitoring? which follows up on one presentation that discussed an observation about past large UK helicopter accidents. UPDATE 21 October 2015 – Further Resources: A follow up RAeS conference is planned for 6-7 July 2016 (not April 2016 or late July as originally announced). The European Helicopter Safety Team (EHEST) has published: Safety Leaflet HE9 Automation and Flight Path Management At the EHEST Safety Worksop at Helitech in London in October 2015: The UK CAA gave this presentation: Training – Overview of Automation Issues Airbus Helicopters presented: Training – For Automation UPDATE 9 January 2017: HeliOffshore have released a HeliOffshore Automation Guidance document and six videos to demonstrate the offshore helicopter industry’s recommended practice for the use of automation. UPDATE 18 February 2018: Autopilot, Mind Wandering (MW), and the Out Of The Loop (OOTL) Performance Problem. According to researchers from ONERA and CNRS: The OOTL phenomenon has been involved in many accidents in safety-critical industries, as demonstrated by papers and reports that we have reviewed. In the near future, the massive use of automation in everyday systems will reinforce this problem. MW may be closely related to OOTL—both involve removal from the task at hand, perception drop, and understanding problems. More importantly, their relation to vigilance decrement and working memory could be the heart of their interactions. Still, the exact causal link remains to be demonstrated. Far from being anecdotal, such a link would allow OOTL research to use theoretical and experimental understanding accumulated on MW. The large range of MW markers could be used to detect OOTL situations and help us to understand the underlying dynamics. On the other hand, designing systems capable of detecting and countering MW might highlight the reason why we all mind wander. Eventually, the expected outcome is a model of OOTL–MW interactions which could be integrated into...
read more19 July 1989: Sioux City
19 July 1989: Sioux City On 19 July 1989, United Airlines Flight 232, McDonnell Douglas DC-10 N1819U, en-route from Denver to Chicago, suffered an uncontained failure of the number 2 General Electric CF6 engine’s fan disc. This resulted in crippling damage to the aircraft’s hydraulics and flight controls. The crew under Captain Al Haynes managed to control the aircraft by throttle movements and made a crash landing at Sioux City airport in Iowa, which fortuitously was in the middle of an emergency response exercise at the time. Of the 296 people on board, 111 died in the accident but miraculously 185 survived. The National Transportation Safety Board (NTSB) determined that the probable cause was: … the inadequate consideration given to human factors limitations in the inspection and quality control procedures used by United Airlines’ engine overhaul facility which resulted in the failure to detect a fatigue crack originating from a previously undetected metallurgical defect located in a critical area of the stage 1 fan disk that was manufactured by General Electric Aircraft Engines. The subsequent catastrophic disintegration of the disk resulted in the liberation of debris in a pattern of distribution and with energy levels that exceeded the level of protection provided by design features of the hydraulic systems that operate the DC-10’s flight controls. More resources: NTSB summary and report Press coverage of NTSB report FAA Lessons Learnt database Aviation Safety Network database entry Local press reports on the 25th anniversary UPDATE 25 September 2019: Captain Al Haynes sadly passed away aged 87 in August 2019. Aerossurance has extensive air safety, operations, airworthiness, human factors, aviation regulation and safety analysis experience. For practical aviation advice you can trust, contact us at: enquiries@aerossurance.com Follow us on LinkedIn and on Twitter @Aerossurance for our latest...
read moreHong Kong Harbour AW139 Ditching – HKCAD Report Issued
Hong Kong Harbour AW139 Ditching – HKCAD Report Issued The Hong Kong Civil Aviation Department (HKCAD) have issued their report into the ditching of AgustaWestland AW139, B-MHJ, operated by Macau based East Asia Airlines Limited (trading as SkyShuttle), in Hong Kong’s Victoria Harbour on 3 July 2010. From the synopsis: The helicopter took off from Sheung Wan / Sky Shuttle Heliport in Hong Kong at 0400 hrs (1200 hrs). Approximately 2 minutes after takeoff, shortly after the crew had completed the post-takeoff checks while climbing on a north-westerly heading at approximately 350 ft Above Mean Sea Level (AMSL) and at about 70 kt Indicated Airspeed (IAS), the tail rotor assembly detached from the helicopter. The commander immediately entered into autorotation and subsequently made a controlled ditching into the harbour. All pilots and passengers were rescued by the nearby vessels. Six of the 11 passengers received treatment for minor injuries. The accident was notified to the Accidents Investigation Division of the Hong Kong Civil Aviation Department (CAD) by the Fire Services Communication Centre (FSCC) of the Fire Services Department (FSD) at 0405 hrs (1205 hrs) on 3 July 2010. The investigation team, comprising a team of CAD Inspectors of Accidents, started the investigation immediately. Two days later, investigators from the Civil Aviation Authority of Macao Special Administrative Region (AACM), Agenzia Nazionale per la Sicurezza del Volo of Italy (ANSV) and AgustaWestland (AW), the aircraft manufacturer joined the investigation team. The investigation team has made two safety recommendations on the AW139 tail rotor blades. They report the causal factors to be: The failure of the White blade was most probably caused by disbond of pitch control arm and the reduction of torsion box stiffness at the blade root radii area, which when associated with manufacturing strap defects at maximum acceptable values in production specification, caused the ILRS to exceed the maximum allowable limit, resulting in matrix delamination onset and then propagation under ILSS and complete failure of the blade. ([Report paragraph] Reference: 3.1.2.2, 3.1.2.3, 3.1.2.4, 3.1.2.5, 3.1.2.6, 3.1.2.10, 3.1.2.11, 3.1.2.12) The reduction in torsion box stiffness at the White blade root radii area was most probably caused by manufacturing quality lapses and the lack of effective way for checking the integrity of the torsion box after production. (Reference: 3.1.2.4, 3.1.2.8) Disbond of the pitch control arm could have been caused by over shimming of elastomeric bearing installation. (Reference: 3.1.2.6) Similar failures are believed to have occurred on the ground to AW139 A7-GHA of Gulf Helicopters in Qatar on 2 May 2011 and, fatally, offshore Brazil on 19 August 2011 (PR-SEK of Senior Taxi Aereo). Aerossurance understands that the report on the Brazilian accident is due to be published later this summer by the Brazilian accident investigation agency CENIPA (although a preliminary report is available online). The emergency flotation system of B-MHJ kept the helicopter afloat for 18 minutes and met the certification requirement of JAR 29.801(d), said CAD, who go on to comment: Although the sea conditions were compatible with the certification of the equipment, the helicopter was significantly out of balance after ditching due to the loss of the tail rotor and the tail fin section and the ingress of water into the cabin through the opening left behind by the lost left-hand nose window transparency. The out of balance condition subsequently resulted in the overload and...
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