British Airways A319 near London on May 24th 2013, unlatched doors on both engines separated, fuel leak, engine on fire shut down
Last Update: July 14, 2015 / 11:41:31 GMT/Zulu time
The investigation identified the following causal factors:
- The technicians responsible for servicing the aircraft’s IDGs did not comply with the applicable AMM procedures, with the result that the fan cowl doors were left in an unlatched and unsafe condition following overnight maintenance.
- The pre-departure walk-around inspections by both the pushback tug driver and the co-pilot did not identify that the fan cowl doors on both engines were unlatched.
The investigation identified the following contributory factors:
- The design of the fan cowl door latching system, in which the latches are positioned at the bottom of the engine nacelle in close proximity to the ground, increased the probability that unfastened latches would not be seen during the pre‑departure inspections.
- The lack of the majority of the high-visibility paint finish on the latch handles reduced the conspicuity of the unfastened latches.
- The decision by the technicians to engage the latch handle hooks prevented the latch handles from hanging down beneath the fan cowl doors as intended, further reducing the conspicuity of the unfastened latches.
The AAIB analysed with respect to non-compiance with Aircraft Maintenance Manual (AMM) procedures: "The fan cowl doors detached from the aircraft because they remained unfastened following the overnight maintenance shift, and their unlatched condition was not detected during the pre-flight inspections by the co-pilot and the pushback tug driver. The technicians responsible for securing the fan cowl doors on G-EUOE had been trained in the required procedures for opening and closing the doors and were aware of the applicable AMM procedures, but in the interests of efficiency, they chose not to follow them. The fan cowl doors were left unlatched because the technicians intended to return to the aircraft to service the IDGs after collecting the IDG gun and oil from stores. The AMM procedure calls for the hooks to be disengaged, allowing the handles to project lower beneath the cowl, thereby increasing their visibility. The decision by both technicians to leave the latches unlocked but with the latch handle hooks engaged was made because they perceived that, in this configuration, the latch handles do not protrude as far below the cowl, thus reducing the risk of personal injury."
The AAIB analysed that the engineers doing maintenance identified that both IDGs needed servicing, due to the workload they did not anticipate however to be able to complete that task within their shift and decided to defer the task until later in their shift for work load planning. The AAIB continued: "Had an open entry for the required IDG oil uplift been made in G-EUOE’s technical log, as required by the operator’s procedures, it is unlikely that it would have materially affected the outcome in this instance, as the technical log was subsequently removed from the aircraft and taken to the maintenance office in Terminal 5A, where it was eventually completed by Technician A."
Later the technicians intended to return to the aircraft but drove past the stand of G-EUOE and began to work on aircraft G-EUXI without realising their misidentification of both stand and aircraft. The AAIB wrote: "The type of error, described in this report as an ‘aircraft swap error’, was classified by the human factors specialist1 as a ‘slip’, in that the technicians had intended to return to G-EUOE, but their actions did not match the plan. Slips are typically the result of automatic actions - well-practised activities that are not consciously monitored by the human and are therefore vulnerable to being miscued by stimuli in the environment, such as design or layout of signs and interfaces."
The AAIB analysed that a number of measures had been taken to prevent unlatched cowl doors in flight. "However, the continued occurrence of fan cowl door losses on A320‑family aircraft, including the G-EUOE accident, shows that such preventative measures have been only partially effective. A more effective mechanical, or electronic, means of detecting unlatched fan cowl doors is therefore necessary." and continued: "Whilst it is accepted that fan cowl doors were considered to be structure and certified accordingly, this accident, and other fan cowl door loss events, show that the results of failure to latch the fan cowl doors can cause them to detach in flight, potentially hazarding the aircraft. This hazard was not identified using the structural airworthiness assessment in the original type certification."
The AAIB analysed: "Inspection of the fan cowl door latches from G-EUOE showed that the latch high visibility paint was mostly missing from the latch handles. That which remained was partially obscured by blue paint overspray. In this condition, the open latch handles would have been significantly less conspicuous than if they had been painted according to SB V2500-NAC-71-0227. Therefore their condition was a contributory factor in reducing the prominence of the open latches."
With respect to flight preparation the AAIB analysed: "The photographs taken by the member of ground staff during the pre-flight activities show the outboard fan cowl door on the right engine to be open and resting on the hold-open device and two of the fan cowl door latches of the left engine hanging down. These photographs show that there were visual cues that the fan cowl doors were unlatched prior to departure. These cues were not identified by either the tug driver during his aircraft inspection or by the co-pilot during his external walk-around."
The AAIB analysed that a fuel leak was clearly visible from the cabin, passengers alerted the cabin crew to the fuel leak. However, the lead flight attendant, when finally reaching the cockpit 7 minutes after takeoff, did not convey the fuel leak but only reported the damaged engine cowl. The pilots thus remained unaware of the fuel leak until they received an ECAM fuel imbalance message. The AAIB wrote: "Had the flight crew been made aware of the fluid leak from the right engine at an earlier stage, they might have been able to identify the fuel leak more quickly and could have taken appropriate action to mitigate the severity of the event."
The AAIB continued: "Had the leaking fuel not ignited, or had the fuel leak been isolated sooner, there would have been no fire and the event would have been relatively benign. However, an external fire broke out on the right engine when the aircraft was already established on approach to land back at Heathrow. The immediate risk posed by the fire, at such a late stage, meant that a landing at Heathrow was the safest option." and continued: "The QRH fuel leak procedure required the right engine to be shut down and, given the location of the damaged fuel pipe, this would have isolated the fuel leak, preventing the fire. The commander, however, decided that shutting down the right engine would have exposed the aircraft to an unacceptable risk, as the condition and degree of damage to the left engine was unknown and there was no certainty of its continued operation. ... When the fire broke out in the right engine, the risk to the aircraft presented by the fire was greater than that of the condition of the left engine and the commander responded accordingly by shutting down the engine."
The AAIB analysed that following landing fire services immediately began to fight the fire at the right hand engine. The left hand engine however was left running while the crew assessed the situation and communicated with ATC and fire services. The AAIB wrote: "The fire chief was concerned about the risk to evacuation posed by the left engine which was still running. Hence, when asked by the commander if an evacuation should be initiated, the fire chief advised him to hold, resulting in the evacuation being delayed. The fire chief subsequently requested that the left engine be shut down and, once radio communications were re-established with the flight crew following engine shutdown, the fire chief requested that an evacuation be commenced."
This article is published under license from Avherald.com. © of text by Avherald.com.
Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.
Support AeroInside by sending a small tip amount.
A British Airways Airbus A380-800, registration G-XLEF performing flight BA-462 from London Heathrow,EN (UK) to Madrid,SP (Spain), was on approach to…
A British Airways Airbus A320-200, registration G-EUYO performing flight BA-2678 from London Heathrow,EN (UK) to Dubrovnik (Croatia), was climbing…
A British Airways Airbus A319-100, registration G-DBCF performing flight BA-1441 from Edinburgh,SC to London Heathrow,EN (UK), was just about to…
The aircraft, a Boeing 787-8 (G-ZBJB), was being loaded with cargo in preparation for a flight to Frankfurt, and whilst carrying out a Dispatch…
A British Airways Airbus A320-200N, registration G-TTNF performing flight BA-621 from Larnaca (Cyprus) to London Heathrow,EN (UK), was descending…
A Lufthansa Airbus A320-200, registration D-AIUM performing flight LH-1429 from Sofia (Bulgaria) to Frankfurt/Main (Germany), was accelerating for…
A Red Wings Airlines Sukhoi Superjet 100-95, registration RA-89138 performing flight WZ-1279 from Chelyabinsk to Norilsk (Russia) with 81 passengers…
Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.Pick your plan and subscribe
A new way to document and demonstrate airworthiness compliance and aircraft value. Find out more.
Train yourself online in VR with the special course for aviation: "Crisis Communications: Airlines". Find out more.
Never miss an article from AeroInside. Subscribe to our free weekly newsletter and join 4844 existing subscribers.
Popular aircraftAirbus A320
Boeing 737-800 MAX
Popular airlinesAmerican Airlines