Moerdijk Explosion: “Failure to Learn”
Shell Moerdijk Explosion: “Failure to Learn” On 3 June 2014 two major explosions and a fire occurred at a Shell petrochemical plant in Moerdijk, Netherlands. Two employees were injured in the explosions that were heard 20 km away. Debris was found 800 metres away. The Dutch Safety Board has investigated this incident. Currently only the investigation summary is available in English. UPDATE 10 December 2015: The full report in English is now released. The article below has been enhanced with extra details. They have also issued a VIDEO. The Explosion The Propylene Oxide-Styrene Monomer 2 (MSPO2) plant had been shut down to replace catalyst granules and was being restarted. Operators manually increased the warming of the reactors with ethylbenzene. This triggered an unanticipated reaction, gas formation and a pressure build up. Fluctuations in pressure did not cause alarm because operators had become used to fluctuations during previous re-starts and considered them normal. An automatic protection system tripped but had the unintended consequences of preventing the venting of the gas. The rapid pressure rise in the reactors resulted in their explosion. The Causal Factors The DSB comment that: Shell failed to “identify and control risks associated with plant modifications” and the potential for chemical reaction between ethylbenzene and the new catalyst was not identified Design data and knowledge was not translated into plant operating procedures, resulting in discrepancies that were not identified Opportunities existed to stabilise or halt the process but they were not taken by operators Shell “failed to learn sufficient lessons from a previous incident” at a Shell joint venture facility in Nanhai, China in 2010. Failure to Learn Further to the failure to learn from the event in China, the DSB report also noted a reaction runaway occurred at Moerdijk in 1999, despite repeated prior statements by Shell that such an event could not happen in that reactor. The DSB note that the 1999 event, that undermined Shell’s earlier technical analysis, did not prompt a fundamental review. The concept of a failure to learn has been raised in relation to BP after the 2005 Texas City refinery explosion for example, prior to the 2010 Macondo / Deepwater Horizon disaster. It is also the subject of a book of the same title by Australian National University Emeritus Professor Andrew Hopkins. It also can apply to a failure to learn from accidents to other organisations (as we discussed in the case of a US helicopter operator). In contrast the DSB highlight that the local fire and emergency services had learnt from past emergencies (such as the nearby 2011 fire at the Chemie-Pack facility). There were areas for improvement though, such as emergency alerting of the local population. In the 2008 book Resilience Engineering Perspectives, Volume 1: Remaining Sensitive to the Possibility of Failure, John Wetherall writes: …one hallmark of a resilient organisation is that it is prepared not only for its own failures those of which it can learn from others – the more resilient it is, the ‘bigger’ are the lessons it has learnt from others. Safety Management and Regulatory Oversight In light of the shortcomings found at the plant, the DSB oddly report they had a “positive view” of the site’s “comprehensive” safety management system (SMS). They are also complimentary about Shell initiatives such as ‘Hearts and Minds‘ and note that the company has been seen as a leader in safety. However the DSB note that Hearts...
read moreISASI Seminar 2015 – ‘Independence does not mean Isolation’
International Society of Air Safety Investigators Seminar 2015 Aerossurance will be attending the 46th annual seminar of the International Society of Air Safety Investigators (ISASI) 24-28 August 2015, in Augsburg, Germany. Organised by the society’s European chapter, the European Society of Air Safety Investigators (ESASI), this year’s theme is ‘Independence does not mean Isolation’. Programme Aerossurance has extensive aviation safety, airworthiness and accident analysis experience. Contact us at: enquiries@aerossurance.com Follow us on LinkedIn and Twitter @Aerossurance for our latest...
read moreCHIRP – Independent Review
CHIRP – Independent Review The results of an independent review on the work of CHIRP (the Confidential Human Factors Incident Report Programme) have just been published by the British charitable trust. CHIRP Chief Executive Ian Dugmore commented that the review: …reaffirmed the requirement for an independent and confidential reporting system for the UK and recommended that CHIRP should continue broadly in its current format for the benefit of the travelling public and the safety of the aviation community. The Review also recognised the importance of safeguarding CHIRP’s reputation as a trustworthy, confidential, credible reporting system. We have already begun to implement the recommendations and will continue to do so over the coming months. The review was conducted between September and December 2014 and as led by Mr Peter Hunt who was formerly a British Airways Captain, Head of Operating Standards Division at the UK Civil Aviation Authority (CAA) and latterly Director of the UK Airprox Board. The panel comprised: Capt. Tim Cheal (Training Manager, Thomas Cook Airlines) Mr Neil Croxford (Head of Compliance & Safety Management, Monarch Airlines) Ms Mary Gooding (Cabin Safety Manager, Virgin Atlantic Airways) Mr Paul Jones (General Manager Air Traffic Services, Gatwick Airport) Mr Geoff Weighell (Chief Executive, British Microlight Aircraft Association [BMAA]). The panel is reported to have consulted widely before producing their report and 13 recommendations. In particular the panel recommends that: The aviation CHIRP programme continues and that more is done to promote the programme. Further work is done on data analysis. That CHIRP works with CAA to contribute to the new concept of Performance Based Regulation (PBR) and include disidentified reports in the national occurrence database. The trust enhance communication and coordination with CAA to ensure timely ‘outcomes’. The programme is extended to aviation security, ground operations and air displays. The trust exploit synergies with the UK Flight Safety Committee (UKFSC) and the General Aviation Safety Council (GASCo). Aviation security, or more particularly complaints about security searches, have been a major theme in recent years. However, including aviation security staff in the scheme would include a critical aviation sector that is particularly vulnerable to human factors (HF), the original primary focus of CHIRP. The ground handling sector is another area where HF issues are critical and there are major opportunities for cultural enhancement. The panel’s 13 recommendations: 1. The Review Committee strongly recommends that ‘aviation CHIRP’ should continue broadly in its current format for the benefit of the travelling public and the safety of the aviation community. 2. Safeguard CHIRP’s reputation as a trustworthy, confidential, credible reporting system. 3. Maintain CHIRP’s ‘working methods’ insofar as the handling of reports is concerned, responsive to the needs of reporters. 4. Continue to progress IT developments especially as regards the ability readily to extract value from the stored dataset. 5. Working with CAA, ensure that CHIRP data and information add value to the Performance Based Regulation methods. 6. Working with CAA, ensure that suitably disidentified CHIRP reports are included in the national ECCAIRS database. 7. Improve the flow of information between CHIRP and CAA such that communications are timely and effective as regards ‘outcomes’. 8. CHIRP must continue its policies and methods as regards membership of the Advisory Boards. It is important that Members of these Boards are representative and credible. 9. Following the transition to electronic communications, CHIRP must...
read moreUSAF RC-135V Rivet Joint Oxygen Fire
USAF RC-135V Rivet Joint Oxygen Fire A US Air Force (USAF) accident investigation has paradoxically determined that a fire that caused of damage in April 2015 was due to a maintenance error but that no human factors were involved. The Fire On 30 April 2015 RC-135V Rivet Joint reconnaissance aircraft 64-14848 of the 343rd Reconnaissance Squadron, 55th Wing had commenced its take off roll at Offutt Air Force Base, Nebraska on a training flight. As the aircraft passed approximately 45 knots, multiple crew in the rear of the aircraft reported seeing a fire above the galley. The take off was aborted and all 27 crew evacuated the aircraft (four suffering minor smoke inhalation). The Damage The fire burned a hole through the upper fuselage above the rear galley area, damaging aircraft control and mission systems. The repair cost is estimated to be $62.4mn. The Maintenance History Every 4 years, each RC-135 aircraft undergoes Programmed Depot Maintenance (PDM) at contractor L-3 Communications in Greenville, Texas. During PDM, L-3 Communications inspects, cleans and reinstalls the oxygen system in accordance with documents known as Technical Process Specifications (TPS). This was last done on 64-14848 on 21 August 2013. No oxygen system maintenance was conducted in the area of the fire since then. The fittings used in the oxygen system are shown below. They includes B-nuts, the subject of one of our recent articles. The B-nut and sleeve provide a clamping load to create a seal between the tube and fitting. The Investigation Conclusions During investigation it was found that some B-nuts in the oxygen system were finger tight. The USAF report states: The board president found by preponderance of the evidence that the cause of the mishap was a leak in the high-pressure oxygen system due to poor assembly of the system tubing at depot maintenance. Failure by L3 Communications depot maintenance personnel to tighten a retaining nut connecting a metal oxygen tube to a junction fitting above the galley properly caused an oxygen leak. This leak created a highly flammable oxygen-rich environment that ignited. The resulting fire melted the retaining nut causing the tubing to become detached from the junction fitting, feeding more oxygen to the fire, increasing its size, and causing severe damage to the airframe, galley, and mission equipment onboard the aircraft. However, very oddly the report also says: AFI 91-204, Safety Investigations and Reports, 24 September 2008, Attachment 5, contains the Department of Defense Human Factors Analysis and Classification System [HFACS], which lists potential human factors that can play a role in any mishap. Human factors consider how people’s tools, tasks and working environment systematically influence human performance. There is no evidence that human factors contributed to this mishap. [Emphasis Added] There is a HFACS Maintenance Extension (HFACS-ME), similar to Boeing MEDA, that could have been used to analyse the maintenance circumstances but unfortunately that does not seem to have been applied. The report does erroneously suggests the maintenance personnel did not follow a TPS dated May 2014 – i.e. after the work was actually done(!). The Air Force Times reports that: Air Combat Command said no decision has been made on whether the company would be liable for the aircraft damage, calling it a “complex subject.” “The purpose of this report is to provide a comprehensive look at all of the factors that led to this accident,” ACC said in a statement. “The report does...
read moreRockets Sleds, Steamships and Human Factors: Murphy’s Law or Holt’s Law?
Rockets Sleds, Steamships and Human Factors: Murphy’s Law or Holt’s Law? Murphy’s Law: Whatever can go wrong, will go wrong. To some a pessimistic inevitability, to others a call to arms for defensive design to prevent opportunities for failure. We look at how that ‘law’ was named and how the origins of the ‘law’ actually stretch back to a Liverpool ship-owner and engineer in 1877. That Man Murphy ‘Murphy’s Law’ was not reference to a generic accident prone Irishman as some believe, but to Major Edward Aloysius Murphy Jr. USAF (b 11 Jan 1918 d 17 Jul 1990). As described Nick Spark, author of A History of Murphy’s Law, Murphy was a USAF engineer working on instrumentation for an aerospace medical research programme, MX981. The programme used high-speed rocket sleds at Muroc Army Air Field (later renamed Edwards Air Force Base) to examine human tolerance to acceleration and deceleration. The human in question was frequently researcher Colonel John Paul Stapp, MD PhD (b 11 Jul 1910 d 13 Nov 1999). Stapp’s work using the rocket sled had a profound influence in the field of crashworthiness, human survivability and motor vehicle safety. However, it was hazardous work that on a good day left the subject with black eyes (from their eye-balls ‘punching’ their eye-lids) and sometimes worse (Stapp broke several bones), with the greatest deceleration experience by Stapp being 46.2g. https://www.youtube.com/watch?feature=player_detailpage&v=s4tuvOer_GI Murphy had designed a strain-gauge device to more accurately measure the deceleration. When it was first tested, there was massive disappointment as it had not recorded data. When examined it was discovered that it had been mis-wired and in particular there were two ways to wire the unit (only one of which would result in success). Although who said what remains disputed, according to Stapp, at a subsequent press conference on the trials, that was where ‘Murphy’s Law’ was born. https://youtu.be/SRZ4deJsndM Error tolerance of designs had already been recognised in the early days of civil aviation though. In 1925 Major General Sir Sefton Brancker, the UK’s Director of Civil Aviation has said in a presentation to the Royal Aeronautical Society (discussed in Flight): Error of judgement had been the basic cause of 8 out of 12 dangerous accidents. These could be divided into categories, five of which were the fault of the pilot in that he took the wrong action, and three of which were caused by failure to handle the aircraft correctly. The second category did affect the designer. From the beginning the designer had always been prone to assume that his aircraft would be flown by an absolutely first-class pilot. In air transport we want a really foolproof machine… Perhaps ironically Brancker perished in the R101 airship disaster in 1930. However, it appears that the concept named at a Californian dry lake actually has nautical origins… Alfred Holt Liverpool ship-owner and engineer Alfred Holt had formed the Alfred Holt and Company on 11 January 1865. Its main operating subsidiary was the Ocean Steam Ship Company, trading as Blue Funnel Line. Holt, an accomplished marine engineer, formed the company at the height of the great sail-powered clipper ships, to exploit developments in steamship technology. It has been said that Holt “had no romantic feelings for the clippers…and had an unshakeable belief in steam propulsion”. Francis Hyde in his 1957 book Blue Funnel, quotes Holt that “the main problems…centred around the screw propeller, the building of a ship in iron, and the compound engine”. Holt was among the first to combine the three features successfully. The subsequent opening of the Suez...
read moreFuel System Maintenance Error: Tuniter ATR72 TS-LBB Ditching 6 August 2005
Fuel System Maintenance Error: Tuniter ATR72 TS-LBB Ditching 6 August 2005 On the 6 August 2005 a Tuninter ATR72 turboprop aircraft, TS-LBB, flying from Bari, Italy to Tunis, Tunisia, ran out of fuel and ditched off the northern coast of Sicily. Of the 39 people on board, 16 died. The aircraft had been erroneously fitted during maintenance with the Fuel Quantity Indicator (FQI) for the smaller ATR42. The ATR72 FQI was not found in the stores because its part number had been entered into the stores database without the integral ‘dashes’ and the database mistakenly indicated that the ATR42 part, which was found in the database, was compatible with both aircraft types. With the wrong FQI, the quantity displayed exceeded the actual fuel. When fuelled, the difference between the expected fuel and that indicated was not initially noticed. When it was, it was incorrectly believed that a further fuelling had taken place and the records misplaced. When the engines flamed out the crew did not feather the propellers to reduce drag as they were attempting to restart the engines, believing fuel remained (as indicated by the FQI). Consequently they did not fly the aircraft at the optimum speed to extend the gliding distance. This was a classic ‘organisational accident’ unfortunately the a number of individuals were prosecuted. There was also considerable condemnation over the use of the CVR by the prosecutors. The full Agenzia Nazionale per la Sicurezza del Volo (ANSV) report is here and an separate academic paper here. An Airworthiness Directive was issued: F-2005-160 In 2009 the Flight Safety Foundation (FSF) published this useful summary: False Positive The FAA Lessons Learnt Database contains three fuel exhaustion case studies: Title Description Date UAL Flight 173 near Portland On December 28, 1978 a McDonnell Douglas DC-8-61 turbofan powered airplane operated by United Airlines and registered as N8082U, crashed into a wooded suburban area while on approach to Portland International Airport, Portland, Oregon. …more December 28, 1978 Avianca Airlines B707 Flight 52 at Long Island, NY Avianca Airlines Flight 052, a Boeing 707-321B, was a scheduled international flight from Bogota, Colombia, to John F. Kennedy (JFK) International Airport, New York. Poor weather conditions in the Northeast of the US led to the flight being put in …more January 25,1990 Air Transat A330 Flight TSC236 at Terceira Airport, Azores On August 24, 2001, Air Transat Flight TSC236, an Airbus Model 330-243 aircraft, was on a scheduled flight from Toronto, Canada to Lisbon, Portugal. A fuel leak in the Number 2 (right) engine began three hours 46 minutes into the flight that was …more August 24, 2001 Safety Resources See also: B1900D Emergency Landing: Maintenance Standards & Practices Airworthiness Matters: Next Generation Maintenance Human Factors Rockets Sleds, Steamships and Human Factors: Murphy’s Law or Holt’s Law? Professor James Reason’s 12 Principles of Error Management Back to the Future: Error Management Aerossurance has previously examined: Fuel Exhaustion Causes EMB-110 Emergency Landing Canadian KA100 Fuel Exhaustion Accident UPDATE 12 October 2019: ATR72 VH-FVR Missed Damage: Maintenance Lessons Unclear communications, shift handover & roles and responsibilities, complacency about fatigue and failure to use access equipment all feature in this serious incident. UPDATE 25 June 2020: Japanese Jetstar Boeing 787 GEnx-1B Engine Biocide Serious Incident Aerossurance worked with the Flight Safety Foundation (FSF) to create a Maintenance Observation Program (MOP) requirement for their contractible BARSOHO offshore helicopter Safety Performance Requirements to help learning about routine...
read moreLoose B-Nut: Accident During Helicopter Maintenance Check Flight
Loose B-Nut: Accident During Helicopter Maintenance Check Flight Another investigation by the US National Transportation Safety Board (NTSB), published on 13 July 2015, has highlighted poor maintenance standards and continuing airworthiness management in a US helicopter operator. The NTSB report that on 1 January 2014, Airbus Helicopters EC130B4, N133GC, operated by Papillon Airways Inc (PAI), was being flown on a post-maintenance check flight. When on short finals to Boulder City Municipal Airport, Nevada, at about 200 feet above the ground and an airspeed of 40 to 50 knots, the engine flamed-out. The pilot lowered the collective to initiate an autorotation, but was not able to successfully complete the landing. The tail boom touched the ground first and a hard landing ensued. The pilot, the sole occupant, was uninjured but the helicopter, which came to rest on its right side, sustained substantial damage. The NTSB state that during: …examination of the wreckage, a main fuel supply line B-nut fitting was found without the safety wire, and the nut was loose when turned by hand. ‘B-nut’ is a common term for a nut used to connect fluid lines and hoses. They are a regular cause of engine loss of power events, especially on light helicopters. The NTSB go on: Before the accident flight, the line had been disconnected during a task to replace the bidirectional suspension cross-bar assembly, and the accident flight was the first flight since the task was performed. According to the non-certificated maintenance technician who performed the task, the line was removed to defuel the fuel tank, which was contrary to manufacturer’s maintenance manual instructions. Based on the evidence, it is likely that the B-nut fitting was not properly tightened and safety-wired during reassembly, which allowed it to back off due to normal engine vibration and resulted in the interruption of the fuel flow during flight. The Maintenance Manual technique to access the bi-directional suspension cross bar assembly is to remove the main gear box not the fuel tank. Additionally: The maintenance records showed no entry regarding the removal or disconnection of the main fuel supply line. The NTSB determined the probable cause to be: A loss of engine power due to fuel starvation as a result of the non-certificated maintenance technician’s failure to properly tighten and safety wire a B-nut fitting. Contributing to the accident was the maintenance technician’s failure to follow the manufacturer’s maintenance manual instructions. Although the NTSB identifies failures by a mechanic, this accidents highlights issues with how operator’s maintenance organisation planned and supervised maintenance. The NTSB go on to say: Following the accident, PAI implemented a 16-step independent control check to their Safety Control System which will be conducted by only experienced maintenance inspectors. This system is complemented by the addition of the inclusion of exclusively assigned Maintenance Ops Check Pilots who provide an additional level of oversight. An internal maintenance training system was created with heavy focus on FAA CFR 39, 43, 91, to include onsite manufacturer’s training programs that encompass airframe and engine systems. Further details of 13 actions being taken by Papillon can be found in their action plan submission in the NTSB Public Docket (dated 22 April 2015), including a two week safety-standown at their Nevada operations. Despite a range of actions to improve their maintenance organisation, procedures and training Papillion still felt it appropriate to “immediately terminate” 3 employees (the first action listed in the action plan). The...
read more‘Procedural Drift’: Lynx CFIT in Afghanistan
‘Procedural Drift’: Lynx CFIT in Afghanistan (Lynx AH9A ZF540 near Kandahar) ‘Procedural drift’ in the operating detachment was noted by the Service Inquiry into a British military helicopter accident in Afghanistan that killed 5 service personnel. This drift is said to have allowed standards to dilute during sustained operations in theatre. The Military Aviation Authority (MAA) released the Service Inquiry (SI) report on 16 July 2015, into loss of the British Army Air Corp AgustaWestland Lynx AH9A helicopter ZF540 in a Controlled Flight Into Terrain (CFIT) accident in Afghanistan on 26 April 2014. This was the first fatal loss of a British helicopter in 13 years of operations in Afghanistan (although a third party fatality had been caused by a Chinook in 2010). It is also the first Lynx AH9A accident since the first flight of the re-engined variant in 2009 (we provide background on the AH9A below). The Accident The accident occurred during a two-ship vehicle interdiction training mission in the ‘Bowling Alley’ valley on the ‘Texas Helo Range’ range 20 km south of Kandahar Airfield, at a density altitude of 5400ft. The helicopter made a rapid descent, assessed at between 2000ft/min and 2500ft/min, from 400ft above ground level on its final pass. It impacted the ground ‘wings-level’, ~5º nose up, with minimal yaw and “significant forward speed”, leaving a 75m debris trail. The main fuel tanks were compromised and a post-crash fire ensued. The Investigation The SI notes that during the flight (including the last two passes), the military passengers, who were gaining experience of the AH9As operational role, were allowed to fire a General Purpose Machine Gun (GPMG) door gun. The SI Panel comment that this had not been discussed in sufficient depth at the pre-flight briefing and that this part of the sortie appeared more ‘ad hoc’. They also comment on that due to a shortage of Suitable Qualified and Experienced Personnel (SQEP) the commanders authorised each others flights rather than an independent flight supervisor conducting the authorisation. The SI postulates, based on some limited Cockpit Voice Recorder (CVR) data, that a rapid descent may have been deliberate to “provide a thrill for the passengers”, though it is important to note they do also comment positively on the general airmanship and professionalism of the flying. They also note a possible self induced time pressure. The report notes that the entry point on the final pass was different, giving the crew different visual clues. The SI Panel comments that the crew may also have been distracted trying to establish visual contact with the second Lynx. Additionally they note that the radar altimeter (RADALT) was not being used effectively as the ‘bugged’ setting was too low to initiate a recovery in a descent (and was being routinely set lower that required by the standard operating procedures without challenge). The report highlights the pilot got limited sleep (less than 6 hours) the night before and was possibly fatigued. The SI Panel highlighted that issues identified by a standards inspection 10 months earlier (such as under-manning, individual ‘overstretch’ from repeated tours and the quality of training supervision and delivery) were still evident. They also identified lower than expected occurrence reporting from the detachment compared to the rest of the Lynx AH9A fleet and other helicopters detached to Kandahar. A previous Service Inquiry on a loss of control incident involving a Royal Air Force Airbus A330 Voyager made a similar comment about the lack of reporting of lost articles in the RAF transport fleet. Procedural Drift /...
read morePerformance Based Regulation and Detecting the Pathogens
Performance Based Regulation (PBR) and Detecting the Pathogens At a time when Performance Based Regulation (PBR) is a hot topic in the aviation industry, a series of rail accidents in North America help demonstrate the type of poor performance that PBR must successfully detect. These accidents were what James Reason, Professor Emeritus, University of Manchester described as ‘organisational accidents’ in his classic 1997 book Managing the Risks of Organizational Accidents. Reason explained that: Organizational accidents have multiple causes involving many people operating at different levels of their respective companies. Such accidents result from ‘latent organisational failures’ that are, according to Reason, like pathogens that have infected the organisation. A key challenge for an organisation’s Safety Management System (SMS) is detect latent pathogens before they cause harm. PBR needs to give the regulator assurance that the organisation’s SMS is vigilant and effective at doing that. Metro-North, US As we recently discussed, the US National Transportation Safety Board (NTSB) published a special investigation report into the organisational factors that emerged after five accidents at Metro-North (discussed at a special hearing). Metro-North is the second largest commuter railroad, and one of the busiest, in the United States. Between May 2013 and March 2014 Metro-North had five significant accidents resulting in 6 fatalities, 126 injuries and more than $28 million in damages. In 2012 the Federal Rail Road Administration (FRA) issued a Notice of Proposed Rule Making (NPRM) that would require a ‘system safety program’, which the NTSB likens to an SMS in other industries. The NPRM states: Since most of these are procedures, processes, and programs railroads should already have in place, the railroads would most likely only have to identify and describe such procedures, processes, and programs to comply with the regulation. Similar statements have been made in other similar rule-making initiatives in other industries. They help defuse potential complaints about extra red-tape but do raise the question: ‘so is there a real benefit to the proposed regulation’? The prime benefit is of course ensuring that organisations that would not operate an effective SMS voluntarily, at least have to justify their SMS performance to an independent regulator. NTSB observe that: Metro-North has for many years had an SSPP [System Safety Program Plan] that presumably will fulfill the proposed regulatory requirement for such a program. However, while the NTSB investigations found Metro-North had a written SSPP, its implementation was very limited and represented little more than a paperwork exercise. Few Metro-North employees even knew the program existed. The identified deficiencies in the Metro-North SSPP implementation provide a cautionary example to FRA as it finalizes the proposed regulation. They also note that: A management systems approach will require cultural change at the [regulator] as well as in the industry. The US Federal Aviation Administration (FAA) is has introduced their own Part 5 Safety Management System (SMS) requirement Part 121 carriers (as we discussed in June 2015) so the NTSB have issued a timely reminder. We have however previously expressed concerns that the FAA’s fondest for fines may undermine that implementation. Lac-Megantic, Canada The Transportation Safety Board of Canada (TSB), in its final report on the crude oil train derailment and fire that killed 47 people on 6 July 2013 at Lac-Megantic, Quebec expressed concerns about how the regulator, Transport Canada (TC) dealt with SMS regulation (emphasis added): …the first SMS audit to assess the effectiveness of the company’s safety management processes took...
read moreSouthwest Unstabilised Approach Accident
Southwest Unstabilised Approach Accident An unstabilised approach and a late change of control were critical in an accident that resulted in a nose gear collapse at La Guardia say NTSB. The US National Transportation Safety Board (NTSB) has published their report (DCA13FA131) on a Southwest Airlines (SWA) Flight 34, a Boeing 737-700, N753SW, that had a nose gear collapse during a very hard landing (16 ft/s) on 22 July 2013 at LaGuardia Airport (LGA), New York. The aircraft was substantially damaged (and later scrapped) and 8 occupants were injured. On the approach they say: …on final approach, the captain, who was the pilot monitoring (PM), realized that the flaps were not configured as had been briefed, with a setting of 40 degrees for the landing. …the captain set the flaps to 40 degrees as the airplane was descending through about 500 ft altitude, which was about 51 seconds from touchdown. When the airplane was between 100 to 200 ft altitude, it was above the glideslope. Concerned that the airplane was too high, the captain exclaimed repeatedly “get down” to the first officer about 9 seconds from touchdown. About 3 seconds from touchdown when the airplane was about 27 ft altitude, the captain announced “I got it,”… the control column was relaxed to a neutral position and the throttles were not advanced until about 1 second before touchdown. The airplane touched down at a descent rate of 960 ft per minute and a nose-down pitch attitude of -3.1 degrees, resulting in the nose gear contacting the runway first and a hard landing. The airplane came to a stop on the right side of the runway centerline about 2,500 ft from its initial touchdown. The Captain, who it has been reported was fired by the airline after the accident, had joined the airline as a First Officer in 2000 (becoming a Captain in 2007) and had around 12,522 hours total flight time, including about 7,909 hours in 737s, of which about 2,659 hours were as Captain. The First Officer joined the airline at the start of 2012 from the USAF and had about 5,200 hours total flight time, including about 1,100 hours in 737s. The NTSB note that: The operator’s stabilized approach criteria require an immediate go-around if the airplane flaps or landing gear were not in the final landing configuration by 1,000 ft above the touchdown zone… Further, the airplane’s deviation about the glideslope at 100 to 200 ft would have been another opportunity for the captain, as the PM at this point during the flight, to call for a go-around… Accident data suggest that pilots often fail to perform a go-around or missed approach when stabilized approach criteria are not met. A review of NTSB-investigated accidents by human factors researchers found that about 75% of accidents were the result of plan continuation errors in which the crew continued an approach despite cues that suggested it should not be continued. Additionally, line operations safety audit data presented at the International Air Safety Summit in 2011 suggested that 97% of unstabilized approaches were continued to landing even though doing so was in violation of companies’ standard operating procedures (SOPs). The Southwest FOM also states that the captain can take control of the airplane for safety reasons; however, the captain’s decision to take control of the airplane at 27 ft above the ground did not allow her...
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