Smoke / Fumes and Lithium Battery Fire

An engine fire has a definite culprit (which engine) and a definite button (FIRE pb + AGENT). Smoke and fumes are different — you do not even know where it is coming from. So SMOKE/FUMES is the most diagnosis-heavy scenario in the chapter: the core is not "which button extinguishes", it is "mask up to stay alive, anticipate the diversion, then isolate systems one by one to find who is smoking". This article develops that diagnostic philosophy and then the increasingly common lithium battery, which carries a lethal reverse-intuition: an extinguisher stops flames but not thermal runaway — you must cool it with water.

1. Detection and entry — which alerts go to ECAM first, which to the QRH directly

"Smoke or fumes are identified by: - An ECAM alert, or - The cockpit crew without any ECAM alert, or - The cabin occupants... When either the cockpit crew or the cabin occupants detect smoke or fumes, without any ECAM alert, the cockpit crew must refer directly to the [QRH] SMOKE / FUMES / AVNCS / MD SMOKE procedure. If the SMOKE AVNCS VENT SMOKE or SMOKE MD SMOKE alert is activated, the flight crew must apply the ECAM first, and refer afterwards to the [QRH]... For any other smoke ECAM alerts (e.g. LAVATORY SMOKE), the cockpit crew must apply first the ECAM procedure. Afterwards, in the case of any doubt about the smoke/fumes origin, [apply QRH]."

[!warning]- No ECAM cue means you need the QRH more, not less A clear ECAM (AVNCS/MD/LAVATORY) — do the ECAM first (the system has located it for you). Smoke smelled with no ECAM — go straight into the QRH master procedure, because no ECAM = no system location = you need the systematic search most. Least information, most need of the procedure.

2. Global philosophy — time critical, divert first, diagnose second

"Time is critical. This is why a diversion must be immediately anticipated (as indicated by LAND ASAP). Then, after the immediate actions, if the smoke/fumes source cannot be immediately identified and isolated, the diversion must be initiated before entering the SMOKE/FUMES ORIGIN IDENTIFICATION AND FIGHTING part of the procedure."

[!warning]- Divert first, then diagnose — not "diagnose, then decide whether to divert" Smoke and fire develop fast and the aircraft has no serious firefighting means (the cabin carries only hand extinguishers), so if the search fails you are already on your way to an airport. The order is protect (masks) → commit the diversion → then work the source at leisure — the least reversible decision (the diversion) is taken first, and diagnosis happens en route. This is the same "uncertain fire → decision first" family as the cargo hold's "detect and divert" (11) and the MDCC's "depressurise and LAND ASAP" (07).

3. Immediate actions — protect the crew first

"IMMEDIATE ACTIONS — These actions are common to all cases of smoke and fumes, whatever the source. Their objectives are: - Flight crew protection - Avoiding any further contamination of the cockpit/cabin - Communication with cabin crew... It is at the discretion of the flight crew to don the oxygen masks... If required, or in the case that the flight crew are not sure, all flight crew members must don the oxygen mask."

[!warning]- If unsure, everyone masks up Smoke may contain carbon monoxide and toxic products; a couple of breaths can incapacitate. So the threshold for masks is rather don unnecessarily than fail to don. Crew protection precedes anti-contamination and cabin coordination — you must not go down first — coupling into ATA-35 (oxygen), the same nerve the MDCC oxygen calculation (07) draws on. Cabin coordination matters too: with cabin smoke, the crew estimate and report the density and severity to the cockpit.

4. Source identification — isolate systems, read the signs

Finding the source is "isolate systems + read signs". The FCTM guidelines:

"‐ If smoke/fumes initially come out of the cockpit's ventilation outlets, or if smoke/fumes are detected in the cabin, the crew may suspect an AIR COND SMOKE... very shortly thereafter, several SMOKE alerts (cargo, lavatory, avionics) will be triggered... ‐ Following an identified ENG or APU failure, smoke/fumes may emanate from the faulty item through the bleed system... ‐ If only the AVIONICS SMOKE alert is triggered, the crew may suspect an AVIONICS SMOKE. ‐ If smoke/fumes are detected, while an equipment is declared faulty, the crew may suspect that smoke/fumes are coming from this equipment."

[!warning]- "Smoke from the vents, then a burst of SMOKE alerts" is one source broadcast, not fires everywhere Smoke from the cockpit outlets with several SMOKE alerts shortly after is not multi-point ignition — it is the air conditioning carrying one source's smoke around the aircraft (coupling into article 05: ventilation carries smoke). Seeing multiple SMOKE alerts together, think one air-conditioning source broadcasting, not several fires. The FCTM also provides an odour table (smell → suspected source) to give crew and cabin a shared vocabulary and sharpen coordination.

5. REMOVAL OF SMOKE / FUMES — descend to FL 100, before the electrical emergency configuration

When smoke is overwhelming, the removal procedure is used — with an order rule:

"When necessary, the procedure [QRH] REMOVAL OF SMOKE / FUMES must be applied before the electrical emergency configuration is set. Indeed, in electrical emergency configuration [QRH] REMOVAL OF SMOKE / FUMES procedure cannot be applied, since manual control of cabin pressure cannot be selected... while descending to FL 100. Reaching FL 100, the [QRH] REMOVAL OF SMOKE / FUMES procedure will be completed."

[!warning]- If you will remove smoke, do it before the electrical emergency configuration Removal drives the smoke overboard using manual cabin-pressure control plus a descent to FL 100 — and that manual control is gone in the electrical emergency configuration. So when both are needed, REMOVAL first, electrical emergency second, or the removal window is closed. The descent to FL 100 is needed to open the outflow while still maintaining the cabin.

6. Lithium battery — an extinguisher is not enough, cool it with water

Lithium batteries (phones, tablets, laptops) are an increasingly common cabin fire source with counter-intuitive mechanics and handling:

"Fire or smoke from lithium battery is due to thermal runaway in the battery cells. It is important to know that fire extinguishers are efficient on flames but cannot stop thermal runaway. The treatment for thermal runaway of lithium battery is to cool the battery by pouring water or non-alcoholic liquid on the device."

[!warning]- For a lithium battery, Halon / an extinguisher is not enough — you must cool it Thermal runaway is a self-sustaining exothermic chain inside the cells; an extinguisher knocks down the visible flame but the cells keep heating, reignite, and spread to neighbouring cells. The only thing that breaks it is cooling — pour water (even against the instinct "never water an electrical fire", cooling outweighs the conductivity risk here). The handling:

• Tasksharing — if needed, transfer control to the crew member on the opposite side of the fire; the PF requests the cabin CCOM "storage procedure after a lithium battery fire" (a container of water / non-alcoholic liquid to immerse the device). With no cabin crew (e.g. a ferry flight), the PM performs it.
• Flames present — the PM uses a hand extinguisher (protect the airway first: PF on the oxygen mask, PM on the smoke hood).
• After flames out / none — assess whether the device is removable: attached to a cable that will not disconnect → treat as not removable → pour water on it in place and monitor for reignition; removable → put it in the prepared water container.
• Escalation: smoke becomes the greatest threat → REMOVAL OF SMOKE/FUMES; unmanageable → immediate landing.

7. Operations — the decision flow

  smoke / fumes -> ECAM present: ECAM first; no ECAM: QRH directly
   1  immediate actions: masks (unsure -> all don) + prevent spread + cabin coordination
   2  anticipate the diversion (LAND ASAP)
   3  source not isolated -> commit the diversion -> isolate systems / read odours (AIR COND / ENG-APU bleed / AVIONICS / faulty equipment / lithium)
   4  heavy smoke -> REMOVAL OF SMOKE/FUMES (descend FL 100; before electrical emergency)
   5  smoke the greatest threat -> boxed items; unmanageable -> immediate landing

AVNCS SMOKE close-out (hardware 05 + procedure here): avionics smoke → SMOKE AVNCS VENT SMOKE → ECAM first (ventilation reconfiguration to clear/isolate smoke) → QRH; no AGENT to press, all action is ventilation, power and diagnosis. The cargo hold's invisible smoke has its own decision path — article 11.

Self-test

[!note]- Q1. Which entry goes straight to the QRH, which does ECAM first? Why does "no ECAM" need the big procedure more? No-ECAM smoke → QRH directly; AVNCS/MD SMOKE → ECAM first then QRH; other SMOKE → ECAM first, then QRH if origin doubtful. No ECAM means no system location, so the systematic search is needed most.

[!note]- Q2. Why anticipate a diversion up front? What is the logic of "divert first, diagnose second"? Smoke/fire develops fast with little firefighting means; committing the least-reversible decision first means you are en route if the search fails, and you diagnose on the way.

[!note]- Q3. What are the three immediate-action objectives, and the mask threshold? Crew protection, prevent contamination, cabin coordination. Mask threshold: if unsure, all crew don.

[!note]- Q4. Smoke from the vents plus a burst of SMOKE alerts — most likely what, and why not "fires everywhere"? AIR COND SMOKE — one source broadcast around the aircraft by the air conditioning, not multiple ignitions.

[!note]- Q5. Why is an extinguisher not enough for a lithium battery? Removable vs non-removable device? It stops flames but not the internal thermal runaway; only cooling (water) breaks it. Non-removable (fixed cable) → pour water in place and monitor; removable → immerse in the water container.

Key takeaways

References

• FCTM PR-AEP-SMOKE (detection & procedure) — three entry paths, time-critical diversion, immediate-action objectives, mask threshold, source-identification guidelines and odour table.
• FCTM PR-AEP-SMOKE (removal order) — REMOVAL before electrical emergency, descend FL 100.
• FCTM PR-AEP-SMOKE (lithium battery) — thermal runaway, extinguisher insufficient → water cooling, tasksharing, removable/non-removable handling, oxygen mask + smoke hood.
• FCOM DSC-26-30-10 — avionics smoke hardware (article 05).

Independent study material, not an Airbus publication and not endorsed by the manufacturer. Always defer to the current operator FCOM, FCTM, and QRH for operational use.