Air Canada Passenger’s Laptop Cooled In Water After Reports Of Smoke

On December 3rd, an Air Canada Boeing 777-300 performing flight AC849 from London Heathrow to Toronto, sent out a distress signal over radio (PAN-PAN) as it was finishing its climb out of LHR. The reason for the PAN-PAN was due to a report of smoke in a lavatory. The smoke was confirmed as coming from a passenger’s laptop.

The incident occurred on a Boeing 777. Photo: Air Canada

According to The Aviation Herald, the crew reacted quickly, placing the laptop into an “according bag” and cooled it with water. Thankfully, this stopped the laptop from emitting smoke. Once the source of the smoke was confirmed, the flight crew canceled its PAN and resumed its journey to Toronto, making a safe, on-time landing.

The dangers of lithium batteries

Lithium-ion batteries can emit smoke and catch fire for various reasons. As the video below explains (at a very basic level), overheating, rough-handling, and excessive charging can deform the battery and cause it to swell. Swelling then leads to short-circuiting and potentially fire.


Here’s what one pilot on the Air Canada Pilot’s Association (ACPA) website said about the dangers of battery-powered devices on aircraft:


“People just aren’t aware of the potential danger with the batteries that they carry around all day in their devices. But passengers can throw these lithium batteries in bags or pack battery-powered devices in their luggage and not recognize that they are volatile compounds—they are actually dangerous goods. The passenger area is an extremely challenging environment for flight and cabin crews to fight a fire, but the cargo hold is far more unforgiving.” – Unnamed pilot from the Air Canada Pilots Association

From smartphones to laptops to headphones, the number of lithium-ion battery-powered devices onboard planes has grown immensely in recent years. Photo: American Airlines

Procedures for handling a battery experiencing ‘thermal runaway’

Below is a summarized version of ACPA’s position for dealing with these types of batteries and their potential dangers:

  • Raise awareness for all travelers
  • Ensure proper safety equipment aboard aircraft including both fire containment bags and the appropriate fire-resistant tool to handle an overheating device
  • Proper training for crews in case of smoke or fire from a portable electronic device
  • Prohibit all lithium-ion batteries or devices from the cargo hold of an aircraft

ACPA says that these types of fires can be managed by immersing the device in water, “to ensure the prompt cooling and/or extinguishing an overheating battery”. In fact, comparing the information published by ACPA and what happened on AC849, it seems that the cabin crew knew exactly what to do.

What a fire containment bag looks like. Photo: Brimstone Fire Protection


A small device overheating may not necessarily seem deadly at first glance. However, the consequences could be dire if smoke continues to fill the cabin. Typical commercial aircraft only take in 50% of its air from the outside. The other 50% being recirculated air; so things can get worse quite fast.

Does the proliferation of lithium-battery-powered devices onboard aircraft worry you? Or is this type of risk something calmly accept? Let us know in the comments.

We reached out to Air Canada to get an official statement on the incident. No response was received at the time of publishing.


Leave a Reply

3 Comment threads
3 Thread replies
Most reacted comment
Hottest comment thread
6 Comment authors
newest oldest most voted
Farhan Nazar

Lots of inflight passenger related mishaps happens last week, eh?


“ACPA says that these types of fires can be managed by immersing the device in water, “to ensure the prompt cooling and/or extinguishing an overheating battery”.” Water will not stop a thermal runaway of a lithium ion battery. Water entering the cell is also dangerous. The bag here was used to keep the battery out of the water, and the water was only used to cool a battery that was starting to get hot, or it could have even been a different part of the laptop. That quote is very misleading and could cause a person who doesn’t know any… Read more »


AC cabin crew SOP is to put the device into fire containment bags with water or liquid in accordance with the bag’s manufacturer instructions.


Lithium mixed with water makes a very explosive mix. I am surprised to read that water was used to cool the device. I would think that a containment bag using halon or AVD would be safer ?


If you do some research you will find that water is a recommended method to cool an overheating li-ion battery. It is not recommended for lithium-metal batteries (non-rechargeable).

Moaz Abid

The same thing has happened on the 787’s battery