Swollen power bank in the seat pocket
Three hours into a 6-hour night flight, cabin crew smell acrid burning plastic near row 23. The passenger in 23C has a power bank (20,000 mAh, 74 Wh) in his seat pocket; it is visibly swollen, hot, and emitting white smoke and sparks. He says he dropped it while it was charging his phone. In his open cabin bag are a second, larger spare power bank marked 30,000 mAh (111 Wh) and a spare e-cigarette. The aircraft carries Halon extinguishers, fire gloves, a fire containment bag, PBE and water-based extinguishers in the galley. There are 162 passengers and 4 cabin crew. The nearest suitable airport is 45 minutes away; the destination is 3 hours away. The seat-pocket fabric is beginning to scorch.
1. Set out your containment sequence in order and state what you must not do, with the reason for each step.
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Order of priorities: protect people - stop the flame - cool the cell - contain - monitor - inform.
- Gloves on (fire gloves, not examination gloves). Have the PBE within reach but do not don it unless smoke thickens - you cannot manage the device with your vision obscured.
- Identify and move the device. Remove it from the seat pocket using the fire gloves or tongs and put it on the floor in the aisle, or straight into the containment bag. Never bare hands, never into an overhead bin, never carried through the cabin, never handed back to the passenger. Why: a swollen cell is already in thermal runaway; a bin concentrates heat and smoke at ceiling level and puts it beside other bags and other batteries.
- Knock down the flame with a short burst of Halon. Then cool with water or a non-alcoholic liquid poured over the device. Why: a lithium-ion cell supplies its own oxygen, so Halon stops the visible flame but does not stop the reaction - cooling is what ends it. Do not use ice or dry ice (thermal shock, and CO2 does not cool), and do not simply smother it with a blanket.
- Contain and monitor. Device into the fire bag or a metal container on the floor where it can be seen; keep it wet; post a crew member with it for the rest of the flight. If it reignites, repeat cooling; expect it to.
- Deal with the surroundings. Wet the scorched seat pocket and any blanket or clothing; remove flammable material from the row; move passengers away from the row.
- Tell the flight deck immediately - what is burning, where, what you have done, smoke level, whether anyone is affected. Do not wait until it is under control.
Specific prohibitions: no water on a device still connected to aircraft power (disconnect first); no opening a cabin window; no attempt to "let it burn out" unattended.
2. What is the position on the second power bank and the e-cigarette, what do you do with them now, and what do you do about the passenger?
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The 111 Wh spare. Spare lithium-ion batteries up to 100 Wh may be carried in the cabin without approval; 100–160 Wh requires the operator's approval; above 160 Wh is forbidden in passenger baggage. On its face this one is not permitted unless your operator's approval scheme covers it and the passenger declared it and was approved. You cannot resolve that question at cruise. The safe immediate action is to treat it as a hazard: inspect it for swelling or damage, protect the terminals (tape or a case), place it in a fire bag or metal container away from heat and out of the passenger's reach, and monitor it. It must stay in the cabin - never into the hold - and the passenger must not continue charging anything.
The e-cigarette. Permitted in carry-on only, forbidden in checked baggage, and its use on board is prohibited. The more immediate issue is the cigarette end: check the waste bin, and if there is any heat source in it, wet the contents. A paper bin with a heat source is a second fire waiting to happen.
The passenger. Take his details, seat, the device make/model and rating, and a short factual statement. Do not argue, and do not confiscate property beyond keeping the hazardous items safe - but tell him clearly what you have done and why. He is subject to the operator's conditions of carriage and to the dangerous goods rules; the commander decides whether he is met on arrival.
Reporting. Give the flight deck the device detail (mAh, Wh, make, damage observed). A dangerous goods incident on board must be reported by the operator to the authority - the detail you collect now is that report.
3. On what basis would you recommend a diversion, and what happens to the device and the paperwork on arrival?
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Recommend diversion when the fire is not actually out:
- the flame cannot be extinguished, or the device reignites after cooling;
- smoke continues to be produced, thickens, or reaches the flight deck;
- the containment bag becomes too hot to handle or the device cannot be kept wet;
- anyone shows smoke inhalation symptoms (cough, hoarseness, headache, nausea, confusion).
With 45 minutes to a suitable airport against 3 hours to destination, a still-active cell makes the choice obvious. If the device is cool, contained, sealed and under continuous watch, continuing with a monitored device is a defensible option - but it is the commander's decision on your facts, and you should say plainly which of those two situations you are in.
On arrival
- Hand the device and the containment bag to the ground fire service or the operator's dangerous goods focal point. It does not go back to the passenger and it does not go into the aircraft waste bin.
- Photograph the device, the bag, the scorched seat pocket and the seat; keep the seat and row number.
- Keep crew statements and the fire log (times of ignition, extinguishing, cooling, monitoring).
Paperwork. Complete the dangerous goods occurrence report: passenger name and seat, device rating, how it was carried, what happened, what was used to fight it, injuries, and the aircraft's position at the time. The operator notifies the NCAA; the commander files the occurrence report. Do not discuss the incident with media - refer them to the operator.