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Chapter 6. Fire

Table of Contents

6.1. Smoke and fumes
6.2. Smoke/ fumes removal
6.3. Engine fire
6.4. Lithium Battery Fire

6.1. Smoke and fumes

The QRH procedure should be applied when smoke is detected and the crew suspect the avionics, air conditioning or cabin equipment as the source. The paper procedure includes all the steps of the avionics smoke ECAM procedure, so if this caution is triggered, the paper procedure should be applied instead of the ECAM[23]. The FCTM also adds that the AVIONICS SMOKE ECAM procedure should be applied only if the flight crew can confirm it visually or by smell, otherwise it should be considered spurious.

In the case of other smoke related ECAMs, the relevant ECAM procedure should be applied first and then the use of the paper checklist considered.

While the smoke aspect of these procedures is fairly unambiguous, the fumes aspect has led to both under- and over-reaction in the simulator. Training department guidance is that if a “smell” is detected in the cabin and it is having no physiological effects, no immediate action is required. If there are physiological effects, the SMOKE/FUMES/AVNCS SMOKE QRH procedure should be actioned. However, only the first line, LAND ASAP, is actioned since there is no perceptible smoke and the rest of the checklist is below the line “if perceptible smoke apply immediately”. Thus after cross-confirming LAND ASAP, immediately move on to the REMOVAL OF SMOKE/FUMES QRH checklist. It should be noted that confirmation of the correctness of this advice is currently being sought from Airbus, and that in a number of in-service events the source of the smell has been positively identified as one of the packs.

Rain repellent fluid leaks are not covered. Orange peel smells are toxic, pine needle smells non-toxic.

The SMOKE/ FUMES/ AVNCS SMOKE checklist attempts to isolate the source of the smoke. It is possible that it may become impossible to carry out this checklist due to smoke density. In this case, interrupt the checklist and carry out the smoke removal drill (see Section 6.2, “Smoke/ fumes removal”). It is also possible that the situation may deteriorate to a level that an immediate forced landing becomes the preferable option. In general, unless the source of the smoke is obvious and extinguishable, a diversion should be initiated immediately. The smoke removal drill is most effective and adaptable at lower levels, so a descent to 10,000ft or MSA is also a priority.

The first priority is to protect yourself, so get an oxygen mask on. The mask must be set to 100% oxygen to exclude fumes; at minimum dispatch oxygen levels this will provide as little as 15 minutes of protection. Pushing the “Emergency pressure selector” knob will provide a few seconds of overpressure, which can be used to clear any smoke trapped in the mask as it was donned.

Likely sources of smoke are the avionics, the cabin fans and the galleys. Smoke from these sources can be contained with simple and reversible actions which can be initiated immediately: put the avionics ventilation into smoke removal mode by selecting both blower and extract fans to OVRD, turn off the cabin fans and turn off the galleys.

Where the source is immediately obvious, accessible and extinguishable, isolate the faulty equipment. Otherwise the QRH provides separate drills for suspected air conditioning smoke, suspected cabin equipment smoke or suspected avionics/ electrical smoke. In addition the avionics/ electrical smoke drill includes undetermined and continuing smoke sources.

Suspect air conditioning smoke if it initially comes out of the ventilation outlets. Several ECAM warnings are also likely to occur as sensors detect the smoke in other areas. The displayed ECAM procedures must be applied. Following an engine or APU failure, smoke may initially enter the air conditioning system but should dissipate quickly once the failure is contained. The air conditioning drill starts by turning the APU bleed off in case this is the source. The packs are then turned off one at a time to determine if the source of the smoke is a pack.

The cabin equipment smoke drill involves selecting the commercial button off and searching for faulty cabin equipment.

Suspect avionics smoke if the only triggered ECAM is AVIONICS SMOKE. If an item of electrical equipment fails immediately prior to the appearance of the smoke, that equipment should be suspected as the source. The avionics/ electrical drill (which includes the undetermined source drill) reduces the amount of electrically powered equipment to a minimum by adopting a slightly modified emergency electrical configuration.[24] The resulting ECAM may [25] contain instructions to reset the generators; these instructions should be disregarded, although the rest of the ECAM procedure must be actioned. The intention is to restore power 3 minutes before landing or at 2000ft aal. Since you will not be able to restore the two IRs that were depowered, the landing will be in Direct Law and hence CONF 3.[26] This is not mentioned in QRH AEP.SMOKE SFAS, and is only mentioned on the ECAM once gear is extended.


6.2. Smoke/ fumes removal

Smoke removal procedures initially use the pressurisation system to draw smoke and fumes overboard by increasing the cabin altitude. If there are no fuel vapours present, the packs are used to drive the smoke overboard. Otherwise it is driven overboard by residual pressure.

The final target configuration is packs off, outflow valve fully open and ram air on. As this depressurises the aircraft, it can only be achieved at lower levels (preferably FL100). If in emergency configuration, turning the APU master switch on connects the batteries for a maximum of 3 minutes and allows manual control of the DC powered outflow valve motor. Once at a suitable level and below 200kt, as a last resort PNF’s cockpit window can be opened.


6.3. Engine fire

The basic sequence is to bring the thrust lever of the affected engine to idle, turn off its engine master, push its fire button, wait 10 seconds then deploy its first fire bottle. If the fire is not extinguished after 30 seconds, indicated by the fire button remaining lit, deploy the second bottle.

This sequence is modified on the ground in that both fire bottles are fired immediately. Cross confirmation is not required for master switches or fire buttons when operated on the ground. The emergency evacuation procedure is then applied (see Section 2.7, “Evacuation”).


6.4. Lithium Battery Fire

If there are flames, they should be attacked with a halon extinguisher. This will necessitate PF donning a crew oxygen mask and PNF donning the smoke hood.

If there are no flames, or once the flames have been extinguished, the cabin crew should remove the device from the cockpit and store it in a lined container filled with water. If the device cannot be removed, water or non-alcoholic liquid should be poured on the device, and it should be continuously monitored for re-ignition.

Note that these procedures assume that you are dealing with lithium ion batteries (i.e. rechargeable batteries found in laptops, tablets, phones etc.) where the amount of water reactive lithium metal is actually fairly low. Once the flames have been knocked down, the focus is on cooling to prevent thermal runaway in adjacent cells. Counter-intuitively, it is vital that ice is not used as this acts as a thermal insulator and will likely cause adjacent cells to explode. For the same reason, smothering with anything that might thermally insulate the battery pack (e.g. a fire bag) is probably a bad idea.

If smoke becomes the biggest threat, see Section 6.2, “Smoke/ fumes removal”. If the situation becomes unmanageable, consider an immediate landing.

[QRH AEP.SMOKE, FCOM PRO.AEP.SMOKE, FAA videos (available on youtube)]

[23] There is an odd airframe dependency with this; on some airframes the instruction is to run the paper checklist at latest after completing the immediate actions of the Avionics Smoke ECAM, whilst on others it is when requested by the Avionics Smoke ECAM. Unfortunately the Avionics Smoke ECAM itself is not described in the FCOM. A general policy of running the paper procedure instead of the Avionics Smoke ECAM procedure seems to cover all eventualities.

[24] The EMER ELEC GEN 1 LINE button rather than the GEN 1 button is used to disconnect generator 1 which disconnects generator 1 from the electrical system but allows it to directly supply one fuel pump in each wing tank.

[25] Which ECAM procedure is displayed is dependent on whether an AVIONICS SMOKE ECAM has been triggered prior to the adoption of emergency electrical configuration.

[26] QRH AEP.ELEC ELEC EMER CONFIG Sys Remaining indicates that by selecting the ATT HDG selector to CAPT 3 it may be possible to retain IR3 and hence have sufficient equipment for a Cat 3A landing once power is restored. This has not yet been confirmed by Airbus.