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  • A332, vicinity Brisbane Australia, 2013 (Synopsis: On 21 November 2013, an A330 rejected its take off from Brisbane after an airspeed indication failure. Following maintenance intervention, a similar airspeed indication fault on the subsequent departure was reported to have been detected after V1. Once airborne, reversion to Alternate Law occurred and slat retraction failed. After an air turnback, it was discovered that the cause of both events was blockage of the No. 1 Pitot Head by a mud-dauber wasp nest which was created during the initial two hour turnround at Brisbane. Investigation of a 2014 event to a Boeing 737 at Brisbane with exactly the same causation was noted.)
  • C525, vicinity Bournemouth UK, 2019 (Synopsis: On 13 April 2019, an experienced Cessna 525 pilot almost lost control shortly after takeoff from Bournemouth when a recently installed performance enhancement system malfunctioned. After a six minute flight involving a potentially hazardous upset and recovery of compromised control, the turn back was successful. The Investigation found that although the pilot was unaware of the supplementary procedures supporting the modification, these did not adequately address possible failure cases. Also, certification flight tests prior to modification approval did not identify the severity of some possible failure outcomes and corresponding Safety Recommendations were made to the system manufacturer and safety regulators.)
  • A320, vicinity Dublin Ireland, 2015 (Synopsis: On 3 October 2015, an Airbus A320 which had just taken off from Dublin experienced fumes from the air conditioning system in both flight deck and cabin. A 'PAN' was declared and the aircraft returned with both pilots making precautionary use of their oxygen masks. The Investigation found that routine engine pressure washes carried out prior to departure have been incorrectly performed and a contaminant was introduced into the bleed air supply to the air conditioning system as a result. The context for the error was found to be the absence of any engine wash procedure training for the Operator's engineers.)
  • A321, vicinity London Gatwick, UK 2020 (Synopsis: On 26 February 2020, after difficulty starting an Airbus A321 left engine for the first flight of the day, the same difficulty recurred on the third flight followed by subsequent en-route abnormalities affecting both engines. After no fault was found during post flight maintenance investigation, similar problems occurred starting the left engine and after takeoff from Gatwick, both engines malfunctioned and a MAYDAY return followed. The continuing Investigation has already found that the engine problems were attributable to fuel system contamination following the addition of 37 times the maximum permitted dosage of Kathon biocide during prior scheduled maintenance work.)
  • DH8C, vicinity Abu Dhabi UAE, 2012 (Synopsis: On 9 September 2012, the crew of a DHC8-300 climbing out of Abu Dhabi declared a PAN and returned after visual evidence of the right engine overheating were seen from the passenger cabin. The Investigation found that the observed signs of engine distress were due to hot gas exiting through the cavity left by non-replacement of one of the two sets of igniters on the engine after a pressure wash carried out overnight prior to the flight and that the left engine was similarly affected. The context for the error was identified as a dysfunctional maintenance organisation at the Operator.)
  • L410, Isle of Man, 2017 (Synopsis: On 23 February 2017, a Czech-operated Let-410 departed from Isle of Man into deteriorating weather conditions and when unable to land at its destination returned and landed with a crosswind component approximately twice the certified limit. The local Regulatory Agency instructed ATC to order the aircraft to immediately stop rather than attempt to taxi and the carrier’s permit to operate between the Isle of Man and the UK was subsequently withdrawn. The Investigation concluded that the context for the event was a long history of inadequate operational safety standards associated with its remote provision of flights for a Ticket Seller.)
  • B773, Abu Dhabi UAE, 2016 (Synopsis: On 27 September 2016, the left engine of a Boeing 777-300 failed on takeoff from Abu Dhabi after it ingested debris resulting from tread separation from one of the nose landing gear tyres and a successful overweight return to land then followed. The Investigation found that FOD damage rather than any fault with the manufacture or re-treading of the tyre had initiated tread separation and also noted the absence of any assessment of the risk of engine damage and failure from such debris ingestion which it was noted had the potential to have affected both engines rather than just one.)
  • B764, en-route, Audincourt France, 2017 (Synopsis: On 23 August 2017, a Boeing 767-400ER which had departed Zurich for a transatlantic crossing experienced a problem with cabin pressurisation as the aircraft approached FL 100 and levelled off to run the applicable checklist. However, despite being unable to confirm that the pressurisation system was functioning normally, the climb was then re-commenced resulting in a recurrence of the same problem and a MAYDAY emergency descent from FL 200. The Investigation found that an engineer had mixed up which pressurisation system valve was to be de-activated before departure and that the flight crew decision to continue the climb had been risky.)
  • A320, vicinity Delhi India, 2017 (Synopsis: On 21 June 2017, an Airbus A320 number 2 engine began vibrating during the takeoff roll at Delhi after a bird strike. After continuing the takeoff, the Captain subsequently shut down the serviceable engine and set the malfunctioning one to TO/GA and it was several minutes before the error was recognised. After an attempted number 1 engine restart failed because an incorrect procedure was followed, a second attempt succeeded. By this time inattention to airspeed loss had led to ALPHA floor protection activation. Eventual recovery was followed by a return to land with the malfunctioning engine at flight idle.)
  • A320, en-route, east of Cork Ireland, 2017 (Synopsis: On 2 November 2017, the flight crew of an Airbus A320 climbing out of Cork detected a “strong and persistent” burning smell and after declaring a MAYDAY returned to Cork where confusing instructions from the crew resulted in a combination of the intended precautionary rapid disembarkation and an emergency evacuation using escape slides. The Investigation highlighted the necessity of clear and unambiguous communications with passengers which distinguish these two options and in particular noted the limitations in currently mandated pre flight briefings for passengers seated at over wing emergency exits.)
  • SU95, Moscow Sheremetyevo Russia, 2019 (Synopsis: On 5 May 2019, a Sukhoi RRJ-95B making a manually-flown return to Moscow Sheremetyevo after a lightning strike caused a major electrical systems failure soon after departure made a mismanaged landing which featured a sequence of three hard bounces of increasing severity. The third of these occurred with the landing gear already collapsed and structural damage and a consequential fuel-fed fire followed as the aircraft veered off the runway at speed. The subsequent evacuation was only partly successful and 41 of the 73 occupants died and 3 sustained serious injury. An Interim Report has been published.)
  • B752, en-route, Northern Ghana, 2009 (Synopsis: On 28 January 2009 the crew of a Boeing 757-200 continued takeoff from Accra Ghana despite becoming aware of an airspeed discrepancy during the take off roll. An attempt to resolve the problem failed and the consequences led to confusion as to what was happening which prompted them to declare a MAYDAY and return - successfully - to Accra. The left hand pitot probe was found to be blocked by an insect. The Investigation concluded that a low speed rejected takeoff would have been more appropriate than the continued take off in the circumstances which had prevailed.)
  • B753, London Gatwick UK, 2014 (Synopsis: On 31 October 2014, indications of a malfunction of the right over wing emergency exit slide on take off were followed during the return to land by the complete detachment of the slide and un-commanded but controllable roll. The Investigation found that "a series of technical issues with the slide panel and carrier locking devices caused the slide carrier to deploy and the slide to unravel". Although an SB existed to address some of these issues, it had not been actioned on the aircraft. Two operational matters encountered during the Investigation were the subject of Safety Recommendations.)
  • B772, en-route, northern Indian Ocean, 2014 (Synopsis: On 16 April 2014, a pre-flight concern about whether a Boeing 777-200ER about to depart Singapore had been overfuelled was resolved by a manual check but an en-route fuel system alert led to close monitoring of the fuel system. When a divergent discrepancy between the two independent fuel remaining sources became apparent, an uneventful precautionary air turnback was made and overfuelling subsequently confirmed. The Investigation found that a system fault had caused overfuelling and that the manual check carried out to confirm the actual fuel load had failed to detect it because it had been not been performed correctly.)
  • B744, vicinity Dubai UAE, 2010 (Synopsis: On 3 September 2010, a UPS Boeing 747-400 freighter flight crew became aware of a main deck cargo fire 22 minutes after take off from Dubai. An emergency was declared and an air turn back commenced but a rapid build up of smoke on the flight deck made it increasingly difficult to see on the flight deck and to control the aircraft. An unsuccessful attempt to land at Dubai was followed by complete loss of flight control authority due to fire damage and terrain impact followed. The fire was attributed to auto-ignition of undeclared Dangerous Goods originally loaded in Hong Kong.)
  • DH8B, en-route, west northwest of Port Moresby Papua New Guinea, 2017 (Synopsis: On 4 August 2017, a de Havilland DHC8-200 was climbing through 20,000 feet after departing Port Moresby when a sudden loud bang occurred and the aircraft shuddered. Apart from a caution indicating an open main landing gear door, no other impediments to normal flight were detected. After a return to the point of departure, one of the main gear tyres was found to have exploded causing substantial damage to the associated engine structure and releasing debris. The Investigation concluded that tyre failure was attributable to FOD damage during an earlier landing on an inadequately maintained but approved compacted gravel runway.)
  • A320, vicinity Tallinn Estonia, 2018 (Synopsis: On 28 February 2018, an Airbus A320 would not rotate for a touch-and-go takeoff and flightpath control remained temporarily problematic and the aircraft briefly settled back onto the runway with the gear in transit damaging both engines. A very steep climb was then followed by an equally steep descent to 600 feet agl with an EGPWS ‘PULL UP’ activation before recovery. Pitch control was regained using manual stabiliser trim but after both engines stopped during a MAYDAY turnback, an undershoot touchdown followed. The root cause of loss of primary pitch control was determined as unapproved oil in the stabiliser actuator.)
  • B38M, en-route, northeast of Jakarta Indonesia, 2018 (Synopsis: On 29 October 2018, a Lion Air Boeing 737-MAX 8 crew had difficulty controlling the pitch of their aircraft after takeoff from Jakarta and after eventually losing control, a high speed sea impact followed. The Investigation found that similar problems had also affected the aircraft’s previous flight following installation of a faulty angle-of-attack sensor and after an incomplete post-flight defect entry, rectification had not occurred. Loss of control occurred because the faulty sensor was the only data feed to an undisclosed automatic pitch down system, MCAS, which had been installed on the 737-MAX variant without recognition of its potential implications.)
  • DC93, en-route, north west of Miami USA, 1996 (Synopsis: On 11 May 1996, the crew of a ValuJet DC9-30 were unable to keep control of their aircraft after fire broke out. The origin of the fire was found to have been live chemical oxygen generators loaded contrary to regulations. The Investigation concluded that, whilst the root cause was poor practices at SabreTech (the maintenance contractor which handed over oxygen generators in an unsafe condition), the context for this was oversight failure at successive levels - Valujet over SabreTech and the FAA over Valujet. Failure of the FAA to require fire suppression in Class 'D' cargo holds was also cited.)
  • B735, vicinity Madrid Barajas Spain, 2019 (Synopsis: On 5 April 2019, a Boeing 737-500 crew declared an emergency shortly after departing Madrid Barajas after problems maintaining normal lateral, vertical or airspeed control of their aircraft in IMC. After two failed attempts at ILS approaches in unexceptional weather conditions, the flight was successfully landed at a nearby military airbase. The Investigation found that a malfunction which probably prevented use of the Captain’s autopilot found before departure was not documented until after the flight but could not find a technical explanation for inability to control the aircraft manually given that dispatch without either autopilot working is permitted.)
  • AN26, vicinity Cox’s Bazar Bangladesh, 2016 (Synopsis: On 29 March 2016, an Antonov AN-26B which had just taken off from Cox’s Bazar reported failure of the left engine and requested an immediate return. After twice attempting to position for a landing, first in the reciprocal runway direction then in the takeoff direction with both attempts being discontinued, control was subsequently lost during further manoeuvring and the aircraft crashed. The Investigation found that the engine malfunction occurred before the aircraft became airborne so that the takeoff could have been rejected and also that loss of control was attributable to insufficient airspeed during a low height left turn.)
  • MA60, en route, west of Bima Indonesia, 2011 (Synopsis: On 12 December 2011, the crew of a Xian MA60 delayed their response to an engine fire warning until the existence of a fire had been confirmed by visual inspection and then failed to follow the memory engine shutdown drill properly so that fire continued for considerably longer than it should have. The Investigation found that an improperly tightened fuel line coupling which had been getting slowly but progressively worse during earlier flights had caused the fire. It was also concluded that the pilots' delay in responding to the fire had prolonged risk exposure and "jeopardised the safety of the flight".)
  • B743, vicinity Tehran Mehrabad Iran, 2015 (Synopsis: On 15 October 2015 a Boeing 747-300 experienced significant vibration from one of the engines almost immediately after take-off from Tehran Mehrabad. After the climb out was continued without reducing the affected engine thrust an uncontained failure followed 3 minutes later. The ejected debris caused the almost simultaneous failure of the No 4 engine, loss of multiple hydraulic systems and all the fuel from one wing tank. The Investigation attributed the vibration to the Operator's continued use of the engine without relevant Airworthiness Directive action and the subsequent failure to continued operation of the engine after its onset.)
  • A320, Singapore, 2015 (Synopsis: On 16 October 2015, the unlatched fan cowl doors of the left engine on an A320 fell from the aircraft during and soon after takeoff. The one which remained on the runway was not recovered for nearly an hour afterwards despite ATC awareness of engine panel loss during takeoff and as the runway remained in use, by the time it was recovered it had been reduced to small pieces. The Investigation attributed the failure to latch the cowls shut to line maintenance and the failure to detect the condition to inadequate inspection by both maintenance personnel and flight crew.)
  • B752, vicinity New York JFK USA, 2016 (Synopsis: On 7 July 2016, a right engine fire warning was annunciated as a Boeing 757-200 got airborne from New York JFK and after shutting the engine down in accordance with the corresponding checklist, an emergency declaration was followed by an immediate and uneventful return to land. After an external inspection confirmed there was no sign of an active fire, the aircraft was taxied to a terminal gate for normal disembarkation. The Investigation found that a fuel-fed fire had occurred because an O-ring had been incorrectly installed on a fuel tube during maintenance prior to the flight.)
  • A319, vicinity Zurich Switzerland, 2014 (Synopsis: On 17 October 2014, two recently type-qualified Airbus A319 pilots responded in a disorganised way after a sudden malfunction soon after take-off from Zurich required one engine to be shutdown. The return to land was flown manually and visually at an excessive airspeed and rate of descent with idle thrust on the remaining engine all the way to a touchdown which occurred without a landing clearance. The Investigation concluded that the poor performance of the pilots had been founded on a lack of prior analysis of the situation, poor CRM and non-compliance with system management and operational requirements.)
  • A320, vicinity Perth Australia, 2015 (Synopsis: On 12 September 2015, an Airbus A320 autopilot and autothrust dropped out as it climbed out of Perth and multiple ECAM system messages were presented with intermittent differences in displayed airspeeds. During the subsequent turn back in Alternate Law, a stall warning was disregarded with no actual consequence. The Investigation attributed the problems to intermittently blocked pitot tubes but could not establish how this had occurred. It was also found that the priority for ECAM message display during the flight had been inappropriate and that the key procedure contained misleading information. These ECAM issues were subsequently addressed by the aircraft manufacturer.)
  • B773, Singapore, 2016 (Synopsis: On 27 June 2016, a Boeing 777-300ER powered by GE90-115B engines returned to Singapore when what was initially identified as a suspected right engine oil quantity indication problem evidenced other abnormal symptoms relating to the same engine. The engine caught fire on landing. The substantial fire was quickly contained and an emergency evacuation was not performed. The cause of the low oil quantity indication and the fire was a failure of the right engine Main Fuel Oil Heat Exchanger which had resulted in lubrication of the whole of the affected engine by a mix of jet fuel and oil.)
  • S92, en-route, east of St John’s Newfoundland Canada, 2009 (Synopsis: On 12 March 2009, a Sikorsky S-92A crew heading offshore from St. John's, Newfoundland declared an emergency and began a return after total loss of main gear box oil pressure but lost control during an attempted ditching. The Investigation found that all oil had been lost after two main gear box securing bolts had sheared. It was noted that ambiguity had contributed to crew misdiagnosis the cause and that the ditching had been mishandled. Sea States beyond the capability of Emergency Flotation Systems and the limited usefulness of personal Supplemental Breathing Systems in cold water were identified as Safety Issues.)