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Engine/APU on Fire: Guidance for Controllers

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Category: Fire Smoke and Fumes Fire Smoke and Fumes
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Description

This article provides guidance for controllers on what to expect and how to act when dealing with the effects of fire during flight on the aircraft engine(s) or Auxiliary Power Unit (APU) (APU). This article does not focus on ground fire scenarios. There are no standard rules to be followed universally. As with any unusual or emergency situation, controllers should exercise their best judgment and expertise when dealing with engine fire situations. A generic checklist for handling unusual situations is readily available from EUROCONTROL but it is not intended to be exhaustive and is best used in conjunction with local ATC procedures.

There are some considerations which will enable the controller to provide as much support as possible to the aircraft concerned, and also to maintain the safety of other aircraft in the vicinity and of the ATC service provision in general.

Useful to Know

Fire in the air is one of the most hazardous situations that a flight crew can be faced with. A fire can lead to the catastrophic loss of that aircraft within a very short period of time.

An engine fire is normally detected in a timely fashion and in most cases, contained satisfactorily by the aircraft fire detection and suppression systems. However, in certain circumstances (e.g. an explosive breakup of the turbine), the nature of the fire is such that onboard systems may not be able to contain the fire and it may spread to the wing and/or fuselage. Heat from such fire could cause deformation of wing surfaces, affect the aircraft systems, and ultimately compromise the structural integrity of the aircraft leading to loss of control.

Where an engine fire has been successfully contained, there is still a risk that the fire may reignite and therefore it is still advisable for the crew to land the aircraft as soon as possible and allow fire crews and technical personnel to carry out an inspection of the engine.

Anticipated Impact on Crew

A wide range of practical problems could arise in the cockpit following an engine failure associated with:

  • High workload - Such scenarios are associated with intense workload; the crew will carry out the appropriate engine on fire drills.
  • Engine shutdown - Normally the fire drills require shutting down the engine and cutting off fuel and electrical supply to the engine. Following this, extinguishant is fired into the engine and a visual inspection of the affected engine is carried out by a member of the cabin or flight crew (if possible). It should be noted that an engine on fire could still produce thrust; it is a critical element to consider when dealing with engine fire emergencies on single engine aircraft. In addition, it should be noted also that historically there have been cases of improper identification of the problematic engine followed by wrong engine shutdown.
  • Announcing the problem - the crew will communicate the problem to ATC. Non-standard phraseology should be avoided; an emergency (MAYDAY) or urgency (PAN PAN) call should be made.
  • Seeking information and deciding on course of action - the crew will need any information available regarding adjacent aerodromes and weather conditions if they decide to proceed to and land at the nearest suitable aerodrome.

What to Expect

  • Rejected Take Off - if the fire is identified prior to V1, the crew might abandon the take-off during the take-off roll; this will normally be communicated to ATC at the same time.
  • Emergency landing - if the fire occurs after V1 or during any other airborne phase of the flight, the crew will normally complete the take-off and carry out an emergency landing at the nearest suitable airfield.
  • Engine failure - a malfunction, or Uncontained Engine Failure, associated with fire could render the engine inoperative. The emergency procedures followed will depend whether the aircraft is single or multi engined. For a single-engined aircraft, an immediate landing will be unavoidable whether or not a suitable airfield is available.
  • Rate of descent - in the event of an enroute engine fire three descent scenarios are possible. If the fire drill is successful and the fire is out, assuming that there is some distance to the diversion airfield, the crew are most likely to initiate a "drift down" profile resulting in a low rate of descent. If the fire is out and the decision has been made to divert to an enroute airfield or continue to planned destination, the descent rate will be more or less normal for the aircraft type. If the fire is uncontrollable, the flight crew are likely to initiate a high speed/maximum rate descent and divert to nearest airfield.
  • Smoke in the Cockpit - possible intrusion of smoke into the cockpit or the cabin, due to bleed air system contamination, with the associated communication problems due to sound distortion caused by donning of oxygen masks.
  • Pressurisation problems - due to the engine fire/engine shutdown, the aircraft might not be able to stay pressurised. In this scenario, depressurisation is likely to be gradual but depending upon the aircraft type and any collateral damage caused by the fire or uncontained engine failure, the depressurisation could be rapid.

What Help to Provide

Best practice is to follow the following guidelines using the mnemonic ASSIST:

A - Ensure that the reported emergency is well-understood and acknowledged;

S - Establish and maintain separation from other traffic and terrain;

S - Impose silence on your control frequency, if necessary; and do not delay or disturb urgent cockpit action by unnecessary transmissions;

I - Inform your supervisor and other sectors, units and airports as appropriate;

S - Provide maximum support to the flight crew; and,

T - Allow the flight crew sufficient time to manage the emergency.

The controller should be prepared to:

  • Acknowledge emergency on RTF
  • Inform the crew about the nearest suitable aerodrome and provide alternate aerodrome details and weather information as soon as possible
  • Ask for number of Persons On Board (POB)
  • Ask if there are dangerous goods on board
  • Inform the landing aerodrome of the inbound traffic with engine/APU on fire
  • Inform the crew if fire/smoke is observed
  • Offer the pilot an extended final approach
  • Clear the runway according to local instructions
  • Keep the safety strip clear
  • Ensure that a go-around is not necessary due to ATC reasons
  • Anticipate the potential for overheated brakes and burst tire
  • Expect a blocked runway
  • Expect positioning of the aircraft with the burning engine downwind on the runway and immediate evacuation
  • Ensure that towing equipment is on stand-by as appropriate
  • In case of forced landing, record last known position and time

Defences

  • Personal Awareness - ATCOs should always monitor the course and altitude of traffic in their sector. Being constantly aware of any ongoing deviations should provide precious time for vectoring of nearby traffic. If there are any uncertainties - verify until there is no doubt.
  • Adequate Reaction - Some of the possible actions: transfer all other aircraft to another frequency (possible broadcast to all stations to increase awareness); leave the emergency traffic on the current frequency; increase the volume of the receiver; have a colleague (a separate pair of ears) to also listen to all transmissions from the aircraft.
  • Technological Limitations - Try to keep aircraft within radar cover. Have in mind the features of the existing radar system.
  • Organisational Awareness - The fast provision of ATCOs during emergency situations should be an objective at administrative level. Periodic training and drills are likely to improve intra-organisational coordination.

Related Articles

Accidents and Incidents

The following events involved engine fire:

  • A319, London Heathrow UK, 2013 (On 24 May 2013 the fan cowl doors on both engines of an Airbus A319 detached as it took off from London Heathrow. Their un-latched status after a routine maintenance input had gone undetected. Extensive structural and system damage resulted and a fire which could not be extinguished until the aircraft was back on the ground began in one engine. Many previously-recorded cases of fan cowl door loss were noted but none involving such significant collateral damage. Safety Recommendations were made on aircraft type certification in general, A320-family aircraft modification, maintenance fatigue risk management and aircrew procedures and training.)
  • E145, Kemi-Tornio Finland 2008 (On 11 December 2008 an EMB 145 being operated by Finnish Commuter Airlines on a scheduled passenger flight caught fire during the taxi in after a night landing after the APU failed to start and a major electrical power failure occurred simultaneously. The fire was not detected until after the aircraft arrived on stand when, with the passengers still on board, a member of the ground crew saw signs of fire at the back of the aircraft. The aircraft’s own fire suppression system was successfully used to extinguish the fire, the passengers left the aircraft and there were no injuries and only minor damage to the aircraft.)
  • MD82, vicinity Lambert St Louis MO USA, 2007 (On September 28, 2007 the left engine of a McDonnell Douglas MD82 caught fire during the departure climb from Lambert St. Louis and an air turn back was initiated. When the landing gear failed to fully extend, a go around was made to allow time for an emergency gear extension to be accomplished after which a successful landing and emergency evacuation from the fire-damaged aircraft followed. The Investigation concluded that the engine fire was directly consequential on an unapproved maintenance practice and that the fire was prolonged by flight crew interruption of an emergency checklist to perform "non-essential tasks".)
  • MD81, vicinity Stockholm Arlanda Sweden, 1991 (On 27 December 1991, an MD-81 took off after airframe ground de/anti icing treatment but soon afterwards both engines began surging and both then failed. A successful crash landing with no fatalities was achieved four minutes after take off after the aircraft emerged from cloud approximately 900 feet above terrain. There was no post-crash fire. The Investigation found that undetected clear ice on the upper wing surfaces had been ingested into both engines during rotation and initiated engine surging. Without awareness of the aircraft's automated thrust increase system, the pilot response did not control the surging and both engines failed.)
  • A310, Khartoum Sudan, 2008 (On 10 June 2008, a Sudan Airways Airbus A310 made a late night touchdown at Khartoum and the actions of the experienced crew were subsequently unable to stop the aircraft, which was in service with one thrust reverser inoperative and locked out, on the wet runway. The aircraft stopped essentially intact some 215 metres beyond the runway end after overrunning on smooth ground but a fuel-fed fire then took hold which impeded evacuation and eventually destroyed the aircraft.)

... further results

The following events involved failure of the APU and/or APU fire:

  • E145, Kemi-Tornio Finland 2008 (On 11 December 2008 an EMB 145 being operated by Finnish Commuter Airlines on a scheduled passenger flight caught fire during the taxi in after a night landing after the APU failed to start and a major electrical power failure occurred simultaneously. The fire was not detected until after the aircraft arrived on stand when, with the passengers still on board, a member of the ground crew saw signs of fire at the back of the aircraft. The aircraft’s own fire suppression system was successfully used to extinguish the fire, the passengers left the aircraft and there were no injuries and only minor damage to the aircraft.)
  • A333, London Heathrow UK, 2016 (On 26 June 2016, thick white smoke suddenly appeared in the cabin of a fully loaded Airbus A330-300 prior to engine start with the door used for boarding still connected to the air bridge. An emergency evacuation initiated by cabin crew was accomplished without injury although amidst some confusion due to a brief conflict between flight crew and cabin crew instructions. The Investigation found that the smoke had been caused when an APU seal failed and hot oil entered the bleed air supply and pyrolysed. Safety Recommendations in respect of both crew communication and procedures and APU auto-shutdown were made.)
  • E145, vicinity Manchester UK, 2001 (On 25 September 2001, an Embraer 145 in descent to Manchester sustained a low power lightning strike which was followed, within a few seconds, by the left engine stopping without failure annunciation. A successful single engine landing followed. The Investigation concluded that the cause of failure of the FADEC-controlled AE3007 engine (which has no surge recovery logic) was the aero-thermal effects of the strike to which all aircraft with relatively small diameter fuselages and close mounted engines are vulnerable. It was considered that there was a risk of simultaneous double engine flameout in such circumstances which was impossible to quantify.)
  • B773, Paris CDG France, 2013 (On 28 July 2013, with passengers still boarding an Air France Boeing 777-300, an abnormal 'burnt' smell was detected by the crew and then thin smoke appeared in the cabin. A MAYDAY was declared and the Captain made a PA telling the cabin crew to "evacuate the passengers via the doors, only via the doors". The resulting evacuation process was confused but eventually completed. The Investigation attributed the confused evacuation to the way it had been ordered and established that a fault in the APU had caused the smoke and fumes which had the potential to be toxic.)
  • F100, Nuremburg Germany, 2015 (On 20 January 2015, The APU of a Fokker 100 being routinely de-iced prior to departing Nuremburg oversped as a result of the ignition of ingested de-icing fluid in the APU. This led to its explosive uncontained failure as the result of which ejected debris entered the aft cabin and smoke occurred. No occupants were injured and all were promptly disembarked. The Investigation found that the de-icing contractor involved had not followed manufacturer-issued aircraft-specific de-icing procedures and in the continued absence of any applicable safety regulatory oversight of ground de-icing activity, corresponding Safety Recommendations were made.)

Further Reading

EUROCONTROL

UK CAA

FAA

Others