Description

On 10 January 2009, a Boeing 747-400 being operated by British Airways on a scheduled passenger flight from Phoenix USA to London had been pushed back from the gate in normal daylight visibility and the engines start was continuing when fumes and smoke were observed in the cabin and flight deck. The aircraft commander decided to return to the stand but there was some delay while the tug was reconnected and the movement accomplished. The intensity of the fumes increased and as the aircraft came to a halt on the stand an emergency evacuation was ordered.

Investigation

An Investigation into the event was carried out by the UK AAIB on behalf of the State of the Operator with the agreement of the National Transportation Safety Board (USA) (NTSB) for the State of Occurrence.

It was found that about a minute after the first engine had been started, an acrid burning smell had been detected on the flight deck and in the cabin. On the flight deck, the fumes intensified and the pilots put on their oxygen masks. After a review of the situation, the aircraft commander decided to return the aircraft to the stand and disembark the passengers. The engines were shut down, the headset operator was advised that the tug, which had by this time been disconnected, should be reconnected, a PAN call was made to ATC and the cabin crew were instructed return the doors to the ‘manual’ position. It took a further four minutes to get the tug attached and a further four minutes to get the aircraft back on stand.

The Investigation established that whilst this was taking place, the situation in the passenger cabin had deteriorated with some passengers leaving their seats and wanting to get off the aircraft, one calling out that there was a fire. Cabin crew saw “whitish smoke” coming from the sidewall and discharged a fire extinguisher under the seats in the area. One passenger opened door 3L whilst it was in manual. The Cabin Crew were no longer able to control the situation in the cabin and one of the cabin crew contacted the flight deck again and advised that there was smoke and possible fire in the cabin. The aircraft commander ordered an evacuation and advised ATC that there was a fire on board and the evacuation was completed down deployed slides onto the apron area. RFFS personnel attended the aircraft but were unable to detect any heat sources or fire damage on the aircraft.

It was concluded that, during the return to stand, “Although trained in emergency procedures and in assertiveness, the cabin crew found it difficult to control the situation and keep the commander informed, particularly as the passengers became more distressed. The physical reality of the passengers’ behaviour was unlike that experienced by the cabin crew during their training.”

A detailed engineering investigation both before and after a ferry flight to the Operator’s maintenance base was unable to establish any source or explanation for the fumes / smoke and the aircraft was returned to service ten days later with no recurrence of the problem.

The Investigation noted that the two hour Cockpit Voice Recorder (CVR) Recording had not been preserved in accordance with applicable Operator and Regulatory Procedures and, upon reviewing previous AAIB investigations, it was found that out of 99 CVR replays, information had been lost in 19 of them because the operator had not electrically isolated the recorder whilst the aircraft was on the ground. Seven of these events related to ‘two-hour’ recorders, with the remaining being ‘half-hour’ recorders and occurrences were found not to be specific to any one operator or any particular domicile of operator.

The Final Report of the Investigation was published on 12 June 2006 and may be seen in full at SKYbrary bookshelf: AAIB Bulletin: 6/2010 EW/C2009/07/09

Safety Recommendations

Two Safety Recommendations were included in the Report, which are reproduced below in full:

• It is recommended that British Airways plc review their procedures and training of flight and maintenance crews to ensure the timely preservation of Cockpit Voice Recorder recordings in the event of a reportable occurrence, in accordance with ICAO Annex 6 Part I, 11.6 and EU-OPS 1.160. The procedures and training should provide the necessary information and skills to identify when reportable accidents and serious incidents occur, and implement the necessary tasks to preserve flight recordings in a timely manner. (2010-011)

• It is recommended that the Civil Aviation Authority review the relevant procedures and training for UK operators, to ensure the timely preservation of Cockpit Voice Recorder recordings of a reportable occurrence is achieved in accordance with the requirements of ICAO Annex 6 Part I, 11.6 and EU- OPS 1.160. (2010-012)

Further Reading

• Passenger Cabin Fire
• Fire Triangle
• Smoke Gases
• Ageing Aircraft - Electrical Wiring
• Maintenance Error Decision Aid (MEDA)