6th of January 2011
An Airbus A319-111 was operating on a scheduled flight from Liverpool Airport to Belfast Aldergrove Airport. It was the third sector from the crew after previously operating a return flight to Madrid Barajas Airport from Liverpool Airport. Onboard 46 passengers, 4 flight crew and 2 flight crew.
Airbus A319 (© Airbus)
The short flight had progressed without any problems and the crew obtained the latest weather information (ATIS) for Belfast during the short cruise phase of the flight;
· Wind – Calm
· Visibility – 2900 in mist
· Cloud – No significant clouds
· Temperature & Dewpoint – -3ºC
· QNH – 1002 mb
Runway 25 was the active runway and was reported wet over the full length. Runways and taxiways had been treated with an anti-icing product to prevent ice from forming in the subzero temperature. The de-icing product used was Potassium Acetate and Urea. The crew was not informed about the application of the anti-icing product. As per airline procedure, the cabin was prepared for the landing and reported ready for landing by the purser. The approach and landing were normal, the preselected auto brake activated and idle reverse was selected. Due to work in progress, the crew was instructed to vacate the runway at the end of the runway by ATC. As ATC requested the crew to keep the speed up prior to vacating the engines remained at idle reverse during the extended landing roll and while vacating the runway.
The co-pilot performed the after landing scan, which included starting the APU and switching Pack 2 Off.
North-western area of Belfast Aldergrove Airport
Shortly after entering Taxiway D, what appeared to be, smoke started to enter the cabin from the overhead vents over the full length of the cabin. The smoke was (later) reported as brown or black in colour, with a smell reminiscent of a bonfire or an electrical fire. Visibility in the cabin was reduced by the smoke. The purser contacted the flight deck crew and informed the first officer about the smoke (the captain did not hear the conversation as he had his service interphone selected off). Engine thrust was selected to forward thrust about that time while the smoke in the cabin became thicker. The purser contacted the flight crew, and the following exchange took place;
- Cabin manager: “I think we need to evacuate” - Commander: “okay” - Co-pilot: “okay” - Cabin manager: “bye”
Subsequently, the captain stopped the aircraft and the copilot thought he made a MAYDAY call advising ATC an evacuation was in progress. However, due to a selection error sent the message over the aircraft’s service interphone. While the flight crew was performing the evacuation checklist the purser initiated the evacuating. With both engines still running both forward doors were opened, the captain immediately shut both engines down. When ATC contacted the aircraft for taxi instructions the captain informed ATC about the evacuation after which ATC initiated the emergency plan for the airport.
The aircraft was successfully evacuated and once outside the aircraft the captain assembled the passengers around him, they were bussed to the terminal a short while later. Firefighters checked the aircraft internally and externally, no signs of fire were found.
Engineers examined the aircraft and could not find any defect that could have caused the smoke. Laboratorium checks of swaps taken from the engine and cabin revealed a significantly higher amount of potassium acetate than a referenced aircraft.
Flight Data Recorder and Cockpit Voice Recorder data for the incident combined ©AAIB
The cause of the smoke was the ingestion of the de-icing fluid from the taxiway, with the long roll out with idle reverse, blowing up the de-icing fluid which was sucked into the engine. The operator and the airport issued safety recommendations, 20 in total. The incident report by the AAIB (Air Accident Investigation Branch) can be found by clicking here.