Uncontained PW1524G Failure During CS100 (A220) Certification Testing
Uncontained PW1524G Failure During Bombardier CS100 (now Airbus A220) Certification Testing The Transportation Safety Board of Canada (TSB) has recently issued its investigation report, into an uncontained engine failure and fire during certification ground testing of Bombardier CS100 (now the Airbus A220-100) C-FBCS on 29 May 2014 at Montréal International (Mirabel) Airport. The crew immediately shut down the Pratt & Whitney PW1524G engine and evacuated the aircraft safely, but the engine and aircraft sustained substantial damage. The Aircraft and Engine The TSB explain: Bombardier announced the development of the C Series aircraft in July 2004. Two variants of the C Series aircraft are offered: the 108–125 passenger CS100 and the 130–160 passenger CS300. The PW1524G is a twin-spool, axial-flow, ultra-high–bypass ratio geared turbofan engine that includes core-mounted angle and main gearboxes. It is part of the PW1000G family of geared turbofan engines that were first run in 2008; the family comprises variants ranging from 15 000 pounds (66.75 kilonewtons [kN]) to 33 000 pounds (146.85 kN) of static thrust. The PW1524G variant, specifically developed for the C Series aircraft, delivers 24 400 pounds (108.5 kN) of thrust. The Investigation TSB describe the failure mode as follows: The investigation determined that “heat soaking,” as a result of insufficient cooldown, caused the seal of a bearing oil feed tube to fail. It was determined that the engine had been shut down after high power operation, without sufficient time for its internal temperatures to reduce at lower power. As a result, when the seal failed, it allowed engine oil to mix with the turbine rotor’s cooling air flow. The resulting air/oil mixture ignited due to high ambient temperatures… …and the ensuing combustion caused the entire [Low Pressure] turbine rotor stage to fail. This resulted in major damage to the engine, nacelle and wing. This damage included: The [failed engine’s] left side thrust link was severed in line with the LPT [Low Pressure Turbine] plane; some engine-air and -oil lines, as well as some electrical wires and fire detection loops, were damaged or severed in the vicinity of the LPT case breach. The left-wing structure sustained major debris impact damage when a segment of the first-stage LPT rotor disk 28 inches long penetrated the wing’s centre fuel tank. The impact created a span-wise gash 33 inches long and 3 inches wide in the carbon composite lower skin plank, inboard of the engine…with a total delamination area of 16 × 37 inches. The turbine disk segment then partially exited through the upper wing plank, where it remained stuck, creating a hole approximately 13 × 7 inches, with a total delamination area of 21 × 10 inches. Signs of burning were found around the hole, although the fuel contained in the tank did not ignite. The TSB explain that: From its initial release until the issuance of the engine’s type certificate by TC [Transport Canada], the Pratt & Whitney PW1500G installation and operating manual (IOM) specified a 10-minute cooling period before shutdown in order to minimize the potential for oil coking in the main engine bearing compartments and to mitigate a bowed rotor start condition. This cooling period was determined based on the results of testing carried out on development engines and demonstrated compliance with the PW1500G’s certification basis. [PWC] issued a Restriction and/or Special Instruction (RSI) with cooling procedures for their engines before shutdown, with alternate solutions for hot shutdowns. Bombardier interpreted the alternate solutions in the RSI as an...
read moreCarrier Arrestor System Maintenance Errors
Carrier Arrestor System Maintenance Errors Eye watering video has emerged of a mishap on the US aircraft carrier USS Dwight D. Eisenhower (CVN 69) in the Atlantic on 18 March 2016. The 1½-inch-thick steel arrestor wire failed during the landing of a Northrop Grumman E-2C Hawkeye and during the go-around the E-2C drops out of sight below the deck edge before climbing away. The investigation highlighted shortcomings in maintenance data. Eight sailors on deck suffered a variety of injuries from the flailing cable, including a fractured skull, facial, ankle, wrist, pelvis and legs with one sailor receiving a possible traumatic brain injury. A Northrop Grumman C-2A Greyhound and a Sikorsky MH-60S Seahawk helicopter parked on deck also received about $82,000 in damage. Safety Investigation According to a US Navy investigation report obtained by The Virginian-Pilot through a Freedom of Information Act request: … maintenance personnel missed at least one and possibly two “critical steps” while working on an engine that helps operate the carrier flight deck’s cables, which are called cross deck pendants, after a previous landing. As a result, the engine failed to slow the aircraft, instead causing the pendant to break “at or near” the Hawkeye’s tailhook. The report said that while there was a “lack of procedural compliance” while troubleshooting an error code from a previous arrested landing, “the sailors involved reasonably believed they had properly and conscientiously completed the complicated procedure.” The maintenance personnel: …were using an approved Navy procedure when they missed steps that led them to misprogram a valve that controls the gear engine’s pressure and energy absorption, according to the report. But that procedure lacked warnings, other notations and wasn’t “user friendly,” Navy investigators found. As a result, while those personnel failed to comply with a “technically correct written procedure,” the Navy found their error understandable because the procedure didn’t explain the basis for its steps, lacked supervisory controls and “failed to warn users of the critical nature” of the valve’s realignment. A command investigation into the incident included recommendations for the development of additional controls for troubleshooting the carrier’s aircraft recovery system as well as a review of the system’s procedures to add necessary warnings, cautions and quality assurance. However, disappointingly, despite recognising the shortcomings in the maintenance data and that “the sailors involved reasonably believed they had properly and conscientiously completed the complicated procedure”: It also included recommendations that Capt. Paul Spedero, commanding officer of the Ike, consider formal counseling, fitness evaluations, qualification removal, requalification or administrative actions for three others whose names were redacted. Other Safety Resources James Reason’s 12 Principles of Error Management 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 maintenance and then to initiate safety improvements: Aerossurance can provide practice guidance and specialist support to successfully implement a MOP. UPDATE 9 November 2016: USMC CH-53E Readiness Crisis and Mid Air Collision Catastrophe UPDATE 8 February 2018: The UK Rail Safety and Standards Board (RSSB) say: Future safety requires new approaches to people development They say that in the future rail system “there will be more complexity with more interlinked systems working together”: …the role of many of our staff will change dramatically. The railway system of the future will require different skills from our workforce. There are likely to be fewer...
read moreDutch Safety Board Investigation: “Medical Assistance on the North Sea”
Dutch Safety Board Investigation: “Medical Assistance on the North Sea” The Dutch Safety Board (DSB) has issued their investigation following the death of a sports diver in the North Sea on 11 July 2015. The Incident Two sports divers were diving on a wreck 18km offshore. One fell ill and was recovered from the water unconscious. An emergency call was made to the Netherlands Coastguard for assistance. The DSB say: By helicopter and ambulance the diver was finally transferred to a hospital in Antwerp, where the victim died that same evening. DSB Investigation The DSB: … investigated the manner in which the assistance was organised and coordinated, as well as how the various parties involved coordinated their actions. The Board also focused on the organisation of medical assistance on the North Sea in general. Details of the Rescue A number of assets were deployed, the DSB say the Coastguard Centre did not keep “a grip on events”, partly due to multiple communication difficulties. Consequently the patient was transferred to a SAR helicopter (contracted from NHV) that did not have medical personnel on board. The Coastguard Centre liaised with the Netherlands Radio Medical Service, whose main role is to provide medical advice to ships in Dutch waters but ‘did not receive a concrete answer’ on where the patient should be taken. After 10 minutes of negotiation, the Academic Medical Centre in Amsterdam refused to accept the patient due to lack of capacity. Despite urgent requests from the SAR helicopter, no firm plan emerged from the Coastguard Centre. Consequently the SAR Helicopter Commander made the decision to transfer the patient to the Erasmus Medical Centre in Rotterdam, arriving with only a few minutes warning. Later in the day the patient was transferred by road to University Hospital Antwerp in Belgium, which had a hyperbaric chamber. The patient died that evening. DSB Analysis The DSB say: There are systematic shortcomings in how medical assistance is provided on the North Sea, which can lead to sick and wounded people not receiving effective, safe and prompt care. The Coastguard’s current process organisation is not appropriate for providing emergency medical care. Their conclusions were: DSB Recommendations Our Observations This incident is a reminder that SAR assets needs to be properly supported. The Flight Safety Foundation (FSF) Basic Aviation Risk Standard for Offshore Helicopter Operations (BARSOHO), launched in May 2015, is orientated around a risk bow-tie, contains a number of common and specific threat controls. While focused primarily on offshore helicopter transport it does also address other associated services, included contracting for SAR. Defence 20.20 is specifically focuses on Emergency Response. Appendix 4 focuses specifically on Transport Hoist, Medevac and SAR support. It contains controls on Emergency Call Outs (Control 13.1) and SAR Call Out, Liaison and Communication Control 17.4). The whole BARSOHO standard is freely available with an accompanying implementation guide. UPDATE 1 February 2017: BARSOHO Version 3, fully aligned with the HeliOffshore SPM, is issued and available. It contains a small number of revisions to the SAR/Medevac requirements. Other Resources You might find this article of interest: Medevac Misadventure – Inquest in the Yukon Aerossurance has extensive safety, special mission aircraft contracting, modification & operation, emergency response and safety analysis experience. For aviation advice you can trust, contact us at: enquiries@aerossurance.com Follow us on LinkedIn and on Twitter @Aerossurance for our latest...
read moreBell 525 Prototype N525TA Fatal Flight Test Accident
Bell 525 Relentless Prototype N525TA Fatal Flight Test Accident NTSB Final Report Issued 16 Jan 2018 – see below in red for a detailed summary and links On 6 July 2016, Bell Helicopter lost the first prototype Bell 525 Relentless super-medium helicopter in a flight test accident in Texas. Both test pilots on-board were killed. N525TA, Flight Test Vehicle (FTV) 1 was undertaking flight tests, accompanied by a Bell 429 chase helicopter. Bell issued the following statement: On July 6, 2016, a Bell 525 was involved in an accident while conducting developmental flight test operations south of our Xworx facility in Arlington, Texas. Unfortunately, the accident resulted in a loss of two crew members. This is a devastating day for Bell Helicopter. We are deeply saddened by the loss of our teammates and have reached out to their families to offer our support. Bell Helicopter representatives are onsite to assess the situation and provide any assistance to local, state, and federal authorities. At this time we ask for your understanding as we work through all of the details. We will continue to provide updates as more information becomes available. TV news footage shows most of the wreckage in one location, where a post crash fire occurred. Initial reports suggested the helicopter may have hit a power line but these appear to have been discounted. However, the rear part of the tail boom and at least one main rotor blade appears to have fallen some distance away (some press reports suggest around 500m). It has been reported that: Flightradar24 records show the helicopter departing Arlington at 10:39 LT (15:39 UTC). It proceeded to the south were it flew pattern at altitudes between 2000 and 3000 feet. Last data point is at 1975 feet, at a speed of 199 kts*at 11:47 hours. *Groundspeed. Unconfirmed reports suggest a 20 kts headwind. One of the test pilots has been identified as former US Marine Jason Grogan. UPDATE 14 July 2016: The other has been identified asanother ex-USMC test pilot, Erik Boyce. UPDATE 19 July 2016: It is reported by Jim McKenna on Aviation Today that: The NTSB team is led by Investigator-in-Charge [IIC] John Lovell and includes [Chihoon] ‘Chich’ Shin, who worked for the U.S. Navy as a helicopter transmissions systems engineer before joining the safety board in 2012, and Van McKinney, a helicopter specialist for the board. Their work is being supported by investigators from the FAA, Bell and General Electric (which makes the 525’s two CT7-2F1 engines). Investigators are assessing the data in the telemetry from the 525 for information about the accident flight and previous flight tests of the aircraft. The NTSB retrieved a flight test recorder from the wreckage and sent to its Washington recorder lab for readout. The safety board described the recorder as being in good condition. But the NTSB has declined to say whether it has retrieved any data from that recorder. Investigators also have interviewed the chase pilots… UPDATE 22 July 2016: Bell 525 flight tests remain suspended but parent company Textron‘s CEO Scott Donnelly says Textron “remains committed to the Bell 525 programme and we’ll work to ensure the aircraft will be a safe, reliable and high-performance helicopter”. UPDATE 25 July 2016: In a further report Jim McKenna of Aviation Today quotes the NTSB IIC as saying the aircraft was on a test of...
read moreErrant Notebook Sends Diving Ship Off-Station – HF in Design
Errant Notebook Sends Diving Ship Off-Station – HF in Design The Australian National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has recently published a safety alert on a serious incident to a Dynamic Position (DP) vessel that made an uncommanded movement during a diving operation that highlighted a significant design vulnerability. The Incident The vessel was conducting diving operations 130m from an oil and gas installation when the uncommanded movement occurred. The loss of position was caused by a deactivation of the forward/aft automatic positioning function by unintentionally deselecting the ‘surge’ button on the DP console located on the bridge which then deactivated the ‘Auto Position’ mode. The deselection was thought to have occurred by the placement of a notepad on the side of the console. The vessel drifted off location by over 40 metres and this drift was initially noticed by a diver when his umbilical started to become taut. Once the DPO (Dynamic Position Operator) became aware of the excursion, the ‘Auto Position’ mode was reactivated causing the vessel to stop moving and remain in position. The diver was unharmed. However as NOPSEMA note: A loss of position during diving could cause diver fatalities if their umbilicals or other equipment becomes entangled or snagged on subsea infrastructure during the excursion. A loss of position whilst working in close proximity to a hydrocarbon facility could also potentially cause a collision, leading to a loss of hydrocarbon containment and subsequent fire or explosion. The NOPSEMA Investigation and Analysis NOPSEMA’s investigation identified that the auto DP mode buttons (Surge, Sway and Yaw) were located in the left hand corner of the console next to desk space commonly used for completing DP related checklists and logs. Consequently, these buttons were susceptible to accidental activation by personnel. The inspectors found that although the incident arose by an accidental and unknowing double press of a button by the DPO, the design of the DP system allowed a human error to escalate this act into a dangerous occurrence by neither requiring any positive confirmation of deactivation of ‘Auto Position’ mode nor providing any alarm that required acknowledgment that ‘Auto Position’ mode had been de-activated. The situation was exacerbated, and recovery impeded, as deselecting the ‘surge’ button automatically deactivates the excursion alarms in that axis and the DP display was no longer providing useful feedback in terms of the loss of position event as the excursion rings started to track with the vessels movement. NOPSEMA identified the following key lessons (with our emphasis): Control system interfaces should be designed to account for foreseeable human error. Adequate control measures to prevent and recover from errors should be in place. For DP vessels, operators need to ensure that suitable controls are in place to prevent a single inadvertent act from leading to a loss of position. Double press activation for switches with safety critical functions may not be an adequate barrier to prevent an inadvertent action. More robust methods need to be considered. DP systems can prevent inadvertent operator selection in several other ways including operation of two separate selection devices and using screen based question pop‐ups. Monitoring tasks are not a human strength; hence control panel operators are heavily reliant on control systems to provide alerts of any unsafe operational conditions, to allow them to problem...
read moreCHC EC225 LN-OJF Norway Accident Investigation Timeline
CHC Airbus Helicopters EC225 LN-OJF Accident Norway (29 April 2016) Investigation Timeline On 29 April 2016, while making a return flight to Bergen-Flesland Airport, Norway from the Statoil Gullfaks B offshore installation, CHC Helikopter Service Airbus Helicopters EC225/H225 LN-OJF broke up in flight, with wreckage falling on land and in coastal waters at Turøy, west of Bergen, Norway. The 13 people on board died in the accident. Witnesses captured video of the main rotor falling separate from the fuselage. The independent Accident Investigation Board Norway (AIBN – the Statens Havarikommisjon for Transport [SHT] in Norwegian) is leading the LN-OJF accident investigation in accordance with the International Civil Aviation Organisation (ICAO) Annex 13 on air accident investigation. On the day of the accident the local aviation regulator, the Norwegian Civil Aviation Authority (the NCAA or Luftfartstilsynet) and then the UK CAA issued operational Safety Directives temporarily prohibiting the use of the type for Commercial Air Transport (CAT): NCAA SD 16/05616-1 UKCAA SD-2016/001 (press statement) We have previously examined the EC225 Main Rotor Head and Main Gear Box Design in detail in a popular background article. Initial Investigation Progress and Early Regulatory Action On 1 May 2016 the AIBN issued the following press release: The Helicopter Accident: The work continues Helicopter wreckage was retrieved from land and the sea bottom Saturday [30 April 2016] and was then transferred to Haakonsvern naval base (Bergen) by ship. The combined Flight Data and Cockpit Voice Recorder was retrieved from the wreckage Friday night [29 April 2016]. The unit was taken to AAIB in England where the process of downloading data has started. Today, Sunday [1 May 2016], the work continues with search for more parts of the helicopter wreckage both at sea and on land. At the same time, the main wreckage and the large components are brought to Haakonsvern (Bergen) for further investigation. On 2 May 2016 AIBN issued an update: The Helicopter Accident: Data from the combined FDR and CVR retrieved. Data is of good quality On 3 May 2016 the European Aviation Safety Agency (EASA), the competent authority for airworthiness across the EU and other EASA Member States, issued Emergency Airworthiness Directive (EAD) 2016-0089-E. This called for a mandatory inspection before next flight to: Check the correct installation of the Front and Right Hand and Left Hand Rear MGB suspension bars in accordance with the instructions of Airbus Helicopters (AH) EC225 Alert Service Bulletin No.53A058. It also calls for the precautionary examination of the MGB Magnetic Chip Detectors (MCDs), MGB oil filter and M’ARMS Health and Usage Monitoring System (HUMS) / Vibration Health Monitoring (VHM) data. This AD did result in findings. For example Australian SDR 510023163: During inspections IAW EASB EC225-53A058, forward suspension bar fitting was found to have bolts more than 20 per cent below the minimum torque as specified in the MMA. Check was previously carried out per AD 2006-0163 four months ago with the results satisfactory. Two similar defects reported. P/No: 332A22161321. TSN: 863 hours/915 cycles. By 6 May 2016, wreckage had been moved from the temporary location in Bergen to the AIBN facility at Lillestrøm, just outside of Oslo: The Helicopter Accident: The search for components is resumed Here, the AIBN will continue its efforts to sort and analyze both components and other information. The participants in the investigation are currently working from their home bases, before the team gathers in Lillestrøm early next week...
read moreEASA Annual Safety Review 2016 Published
EASA Annual Safety Review 2016 Published The European Aviation Safety Agency (EASA) Annual Safety Review for 2016 is now available. In the introduction EASA say: The Review has been published since 2005 and the content of the document continues to evolve. Safety Risk Portfolios are now provided for 10 different operational domains. For the first time analysis is provided on Remotely Piloted Aircraft System (RPAS) operations, otherwise known as drones. The Safety Risk Portfolios directly support the European Plan for Aviation Safety (EPAS). Note there was no Annual Safety Review for 2015 as from this year the year in the title is that of publication not the last full year of data. Overview of Air Accidents in EASA Member States EASA go on to say that in the 32 EASA Member States (the 28 European Union Member States plus Iceland, Liechtenstein, Norway and Switzerland): The top 5 operational domains in terms of the number of fatalities in 2015 were: CAT [Commercial Air Transport] Aeroplanes: In 2015 the domain with the highest number of fatalities was CAT Aeroplanes. This involved a single fatal accident, which was the [A320 D-AIPX] Germanwings accident that occurred on 24 March 2015. In 2014, there were 2 fatal accidents and there has not been more than 2 fatal accidents in CAT Aeroplanes since 2005. This operational domain is the greatest focus of EASA’s safety activities and the reorganisation of the collaborative groups and advisory bodies will help the Agency to learn more about the safety challenges faced by airlines and manufacturers. Non-Commercial Aeroplanes: In terms of fatal accidents, the second highest number occurred in non-commercial operations with aeroplanes. This domain also had the second highest number of fatalities with 65, which is less than the 10-year annual average of 79. The General Aviation Roadmap is key to the Agency’s strategy for non-commercial aeroplanes and the establishment of a Collaborative Analysis Group (CAG) in this area to support the work of the current General Aviation Sub-Safety Consultative Committee will help to identify the most effective safety actions. Gliders/Sailplanes: The domain of glider/sailplane operations had the 3rd highest number of fatalities with 27 and the 2nd highest number of fatal accidents, of which there were 24. Both the number of fatalities and the number of fatal accidents were slightly higher than the 10-year annual average. Aerial Work/Part SPO [Specialised Operations] Aeroplanes: In 2015, there were 2 major accidents involving aerial work/Part SPO operations with aeroplanes. They were an airborne collision between 2 LET-410 aircraft [OM-SAB and OM-ODQ] taking part in parachuting operations in Slovakia, which led to 7 fatalities, and the [Hawker Hunter T7 G-BXFI] Shoreham Airshow accident in the United Kingdom where there were 11 ground fatalities [see UK AAIB Special Bulletins S3/2015, S4/2015 and S1/2016]. These 2 accidents led to a much higher number of fatalities compared with the 10-year annual average despite there being the same number of fatal accidents. Following the Shoreham accident, the UK CAA completed a review of public air display arrangements and produced an associated actions report. In addition, EASA is currently performing specific analysis on parachuting operations to understand more about the risks and consider how improvements can be made with experts from this domain. Non-Commercial Helicopters: non-commercial helicopter operations had the 5th highest number of fatalities, which was a reduction of more than...
read moreANSV Issue AW609 Tilt Rotor Accident Investigation Report
ANSV Issue AW609 Tilt Rotor Accident Investigation Report Investigators say a prototype tilt rotor broke up in flight after a divergent dutch roll developed in a high speed dive. The Italian civil aviation safety investigation authority, the Agenzia Nazionale per la Sicurezza del Volo (ANSV), has issued an interim statement of the loss of prototype #2 (AC2) Leonardo AW609 tilt rotor N609AG in Italy on 30 October 2015, during high speed tests. The two test pilots aboard, Herb Moran and Pietro Venanzi, both died in the accident. The aircraft was on the third run during that test flight to the maximum dive speed of 293 KIAS (on previous flights the highest test point was 285 KIAS). AC2 incorporated a number of modifications in 2013 to reduce drag, including a modified vertical stabiliser. ANSV Accident Investigation The ANSV say that data was successfully recovered from the crash-protected Multi Purpose Flight Recorder (MPFR), a combined Cockpit Voice Recorder (CVR) and Flight Data Recorder (FDR). This was used to help validate telemetry data, however the MPFR lacked key parameters such as latitude, longitude and groundspeed. A flight tests instrumentation recorder and a video recorder (recording images from cockpit and tail mounted cameras) were both destroyed (neither was crash protected). The ANSV say “the Pilot in Command (PIC) felt the onset of oscillations on the roll axis of the aircraft”. He counteracted this by a roll input, the conventional technique. However, the AW609’s flight control laws introduced a yaw input, to counteract an expected flaperon aerodynamic effect in the yaw axis. This created what the ANSV referred to as a phenomenon “like an augmented dutch roll“. Recovered data showed this became divergent and the aircraft then broke up in flight as indicated by the debris plot. AW609 Flight Control and Aerodynamics Tilt rotors have particularly complex flight control laws with multiple rotary wing and fixed wing modes. The AW609 has a triple-redundant fully digital fly-by-wire (FBW) flight control system. BAE Systems provide the flight control computer for the AW609. The ANSV say the high speed behaviour was not replicated in the AW609 SimRX engineering simulator. As discussed above, in 2013 AC2 was modified to reduce drag, including a modified vertical stabiliser and empennage changes. ANSV Safety Recommendations The ANSV has issued three safety recommendations: Two to FAA and EASA on the flight test process and objectives for verifying aircraft handling in high-speed conditions (including via use of wind tunnel testing) One to ICAO on flight data recorders for experimental aircraft AW609 Programme The AgustaWestland US subsidiary, AgustaWestland Tilt-Rotor Company, based in Arlington, Texas, is the applicant for the AW609 certification, which explains why the prototypes are on the US register. An Integrated Development Team is based in Arlington and in Cascina Costa, Italy. At the time of the accident the first prototype, N609TR (AC1), which first flew in 2003, was based in the US whilst the second was at Cascina Costa. AC2 had achieved 567 hours since its first flight in November 2006. Flight tests were voluntarily suspended after the accident in order to fully support the investigation. At the HAI Heli-Expo 2016 in Louisville, Kentucky (1-3 March 2016) AW609 Programme Manager, Clive Scott said: We have a very good understanding of the events and have a view of the most probable causes. That is what’s leading us to say we are expecting to resume flight tests. AC1 resumed flight tests 15 April 2016. Two further prototypes are in build, the...
read moreHEMS Black Hole Accident: “Organisational, Regulatory and Oversight Deficiencies”
HEMS Black Hole Accident: “Organisational, Regulatory and Oversight Deficiencies” The Transportation Safety Board of Canada (TSB) has issued their report into a fatal night-time Controlled Flight Into Terrain (CFIT) accident during a Helicopter Emergency Medical Service (HEMS) departure in ‘black-hole’ conditions. These conditions “typically occur over water or over dark, featureless terrain where the only visual stimuli are lights located on and/or near the airport or landing zone”. On 31 May 2013, at 0011 Local Time, Sikorsky S-76A helicopter C-GIMY, operated by the rotary wing (RW) arm of HEMS provider Ornge, departed from the remote Moosonee Airport in Northern Ontario. As the helicopter climbed through 300 feet into darkness, the first officer commenced a left-hand turn and the crew began carrying out post-takeoff checks. During the turn, the aircraft’s angle of bank increased, and an inadvertent descent developed. The pilots recognized the excessive bank and that the aircraft was descending; however, this occurred too late, and at an altitude from which it was impossible to recover. A total of 23 seconds had elapsed from the start of the turn until impact, approximately one nautical mile from the airport. The aircraft was destroyed by impact forces and the ensuing post-crash fire. All four on board—the captain, first officer and two paramedics—were killed. There was a post crash fire. The helicopter did not have Terrain Avoidance and Warning System (TAWS). On release of the report on 15 June 2016, Kathy Fox, TSB Chair said: This accident goes beyond the actions of a single flight crew. Ornge RW did not have sufficient, experienced resources in place to effectively manage safety. Further, Transport Canada (TC) inspections identified numerous concerns about the operator, but its oversight approach did not bring Ornge RW back into compliance in a timely manner. The tragic outcome was that an experienced flight crew was not operationally ready to face the challenging conditions on the night of the flight. TSB go on: The investigation uncovered several issues. The night visual flight rules regulations do not clearly define “visual reference to the surface”, while instrument flight currency requirements do not ensure that pilots can maintain their instrument flying proficiency. At Ornge RW, training, standard operating procedures, supervision and staffing in key safety/supervisory positions did not ensure that the crew was ready to conduct the challenging flight into an area of total darkness. The training and guidance provided to TC inspectors led to inconsistent and ineffective surveillance of Ornge RW, as inspectors did not have the tools needed to bring a willing but struggling operator back into compliance in a timely manner, allowing unsafe practices to persist. The Operator Ornge (the former Ontario Air Ambulance Corporation renamed in 2006): …is a not-for-profit company responsible for the provision of air medical transport to the population of Ontario. To carry out its mandate, Ornge created 2 for-profit corporate entities to oversee the fixed-wing and rotor-wing aspects of the company’s EMS mandate. They had previously contracted air support but gained a fixed wing AOC in 2009 and a rotary wing AOC 6 January 2012. The company had planned to deploy AW139s in early 2012 to all their HEMS bases, with the exception of Moosonee, which they planned to contract out. However, implementation was delayed due to logistical issues with the AW139’s full ice-protection system, tail-rotor blade airworthiness inspections, and serviceability rates. [and] …the company then elected...
read moreATR72 In-Flight Pitch Disconnect and Structural Failure
ATR72 In-Flight Pitch Disconnect and Structural Failure (Virgin Australia Regional Airlines [VARA] VH-FVR) In 2014 we reported on the preliminary information from the Australian Transport Safety Bureau (ATSB) on a serious incident with a Virgin Australia Regional Airlines (VARA, formerly Perth, WA based SkyWest) ATR 72, registered VH-FVR on 20 February 2014. While operating a scheduled passenger flight from Canberra to Sydney the aircraft sustained a pitch disconnect on final descent. The aircraft was significantly damaged during the occurrence. On 15 June 2016 the ATSB issued an Interim Report. The Incident Flight During the initial climb, while: …Passing 8,500 ft above mean sea level (AMSL), the crew noticed a rapid airspeed increase. The FO [the Pilot Flying] reported that the airspeed trend indicator was ‘off the chart’, indicating a very rapid increase in airspeed. The FO reduced engine power and …temporarily disconnect[ed] the autopilot before manually raising the aircraft’s nose to control the speed. The FO reported that the aircraft felt ‘heavy’, as was normal for this aircraft at that speed, requiring two hands on the controls to move from the then -4° pitch angle. The captain [the Pilot Monitoring] reported being unsure if the FO’s control inputs would be sufficient to avoid exceeding the maximum operating speed limitation, so put one of his hands on the controls and disconnected the autopilot to raise the nose further. ATSB do not comment on any verbal communication between the crew and in particular if the Captain announced his intentions. Shortly after, with both flight crew making simultaneous nose up pitch inputs on the controls, the aircraft rapidly pitched up with an associated increase in the g load. The FO responded by immediately reversing the control input to nose down. Both flight crew noticed that the controls suddenly felt different and ‘spongy’. At about the same time, aural and visual cockpit warnings activated. The crew verified that the aircraft was under control at a stable attitude and speed, observing that it was level or in a slight descent at an airspeed of about 230 kt. One of the cockpit warnings was ‘pitch disconnect’, indicating that the left and right elevator control systems had uncoupled from each other. This allowed for independent movement of the left and right elevators via the captain’s and FO’s control columns respectively. Pitch disconnect is a safety feature intended to allow control of the aircraft in the event of a pitch control system jam. The crew consulted the pitch disconnect checklist and worked to identify which control column was free and working normally. After determining that both controls were free, it was decided that the captain would be pilot flying for the remainder of the approach and landing at Sydney Airport. The aerodynamic loads generated during the pitch disconnect resulted in serious injury to the senior cabin crew member and significant damage to the aircraft’s horizontal stabiliser. It is also noticeable that: Although the aircraft was inspected after the pitch disconnect, the damage was not identified until 25 February 2014. On 25 February 2014, after a further 13 sectors, the aircraft suffered what the crew initially believed was a bird strike after the pitch trim system fluctuated abnormally following an approach in close proximity to birds. Subsequent inspections did find bird debris but did discover damage that ultimately was found to include: External damage to the left and right horizontal stabilisers (aka tailplanes) Fracture...
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