On a recent Qantas A380 flight the pre-flight safety briefing onboard including instructing passengers to “don’t drop your phone” and if you do “ask the crew for help if they lost their phone… and not, repeat not, to try to find it themselves.”
The strange announcement is in response to the fire risk that lithium-ion batteries – which are used to power mobile phones – pose if they are damaged by the moving mechanisms in reclining seats or might be stepped on. Similar announcements have been also been heard on British Airways and Cathay Pacific flights.
But why the sudden warning? In May, on a flight from Sydney to Dallas-Fort Worth, Qantas cabin crew were alerted to the “presence of smoke in the cabin”. The Australian Transit Safety Bureau (ATSB), which has recently released its investigation into the incident, notes that the source of the smoke was traced to seat 19F, in business class – to “a crushed personal electronic device [a phone] wedged tightly in the seat mechanism”.
The phone was no longer emitting smoke when it was retrieved, but “a strong acrid smell remained in the cabin”.
The ATSB, which investigates all Australian aviation safety incidents, said that the crew “placed the [device] in a jug of water,” before putting it in a metal box for the rest of the flight. This tactic was deemed “an excellent example of an effective response to an emergency situation” by the ATSB, and the flight continued as scheduled – landing in Dallas-Fort Worth two hours later.
When pressure is applied to a lithium-ion battery, it is susceptible to short-circuiting. This causes the battery to overheat – and, in some circumstances, start smoking or combust. Aircraft seats must be fire-retardant by law, but that doesn’t stop the heat or smoke.
Dozens of aircraft fires have been linked to lithium-ion batteries: In 2014, a battery short-circuited in a passenger’s bag on-board a Fiji Airways flight, according to an ATSB incident report.
So if you drop your phone on a plane, don’t go shifting your seat to look for it. Not unless you want to risk causing a fire – and have your phone handed back to you as a burnt-out, soggy souvenir of your flight.