Lithium Power Bank Overheating in an Overhead Bin
During cruise on a full flight, a passenger reports that his bag in the overhead bin is hot and smoking. He says it contains a large lithium power bank and a spare battery. There is a thin wisp of white smoke from the bin and a faint chemical smell. The bin is above row 14; the aircraft is full, the aisle is narrow, and passengers in nearby rows are standing up to look. You have a halon extinguisher, a water extinguisher, fire gloves, a PBE, and a containment bag designed for lithium battery fires stowed at the forward galley. The flight crew has been told and asks for your assessment.
1. What is your immediate plan, and why is the containment bag central to it?
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Immediate plan:
- Do not open the bin blindly. Feel the outside for heat, and have passengers in the rows nearby move back and stay seated. Keep the aisle clear.
- Don gloves and PBE if the smoke is irritating; get the halon extinguisher and the containment bag brought to the row.
- Open the bin carefully, identify the item, and if it is a power bank or battery, remove it if you can do so safely without touching a hot or venting cell with bare hands. Use the fire gloves or tongs.
- Place the device in the containment bag and close it. The bag is central because lithium cells generate their own oxygen and heat and can reignite; halon may knock down flames but will not stop the cell from going into thermal runaway. The bag contains the fire, the smoke, and the ejected material, and lets you move the hazard away from passengers.
- If it cannot be moved, discharge halon, then cool with water if the situation allows, and keep the area clear while monitoring.
- Keep the bag in a monitored location away from people and combustible material, ideally in the galley or on a non-combustible surface, and watch it for the rest of the flight.
Never put a venting battery in a normal bin, never use ice or dry ice to cool it, and never leave it unattended.
2. What do you tell the flight crew, and what do you tell the passengers?
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To the flight crew: the item is identified as a lithium power bank and spare battery; whether it is contained in the bag; whether there is still smoke, heat, or visible flame; whether anyone is injured; where the bag is being kept; and that you will keep them updated. That tells them whether this is a contained incident or an active fire, which drives their diversion decision. If it is contained and cooling, continuing may be reasonable; if it is venting, smoking persistently, or there is any fire spread, say so plainly and recommend the earliest suitable landing.
To the passengers: a short, calm PA that does not create alarm: there is a small incident in one part of the cabin, it is being dealt with by crew, please remain seated with belts fastened and keep the aisles clear. Do not speculate, do not name the passenger, and do not invite people to look. Ask the passengers in the immediate rows to stay where they are unless a crew member asks them to move. Brief the crew member monitoring the bag and the crew at the adjacent station so everyone knows what is happening.
3. After landing, what are the reporting and handling obligations, and what mistakes would you flag?
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Reporting and handling:
- File an occurrence report covering the item, its watt-hour rating if known, where it was stowed, what happened, the actions taken, and the outcome.
- Hand the contained device to the appropriate authority or the operator's dangerous goods process; do not return a damaged or venting battery to the passenger, and do not put it in normal rubbish.
- Preserve the containment bag and any damaged material for investigation.
- Record whether the passenger was asked about batteries and what he declared, because undeclared or improperly packed lithium batteries are a recurring cause of these events.
Mistakes to flag: opening a hot bin without checking for heat; handling a venting cell with bare hands; using a normal waste bin or a plastic bag as containment; stowing the bag back in an overhead bin or near passengers; leaving it unattended; using ice or dry ice; assuming halon alone has solved it; and failing to tell the flight crew the true trend. Also flag any failure to brief passengers and crew, because a contained incident that nobody else knows about becomes a panic if smoke reappears.