Why you shouldn't look for your phone on a plane if you drop it

A mobile phone (pictured) caught fire became crushed in a seat on board a Qantas flight from Sydney to Texas. Photo / Australian Transport Safety Bureau

A fire was sparked when a mobile phone became crushed in a seat's mechanism on board a Qantas flight

If your phone goes missing on a flight ask a flight attendant for help and do not go scrabbling around for it yourself, some airlines have been telling passengers.

This announcement was first heard on a Qantas flight from Sydney to New York last week by a reporter at technology website when fliers were "told to ask the crew for help if they lost their phone... and not, repeat not, to try to find it themselves".

Similar notices have also been witnessed on British Airways and Cathay Pacific services.

The unusual request, heard by a reporter for The Register, follows an incident in May earlier this year when a fire was sparked after a mobile phone became crushed in a seat's mechanism on board a Qantas flight from Sydney to Texas.

The Australian Transit Safety Bureau (ATSB) - which has recently released its findings into their investigation - noted: "A passenger alerted the cabin crew to the presence of smoke in the cabin. The cabin crew then initiated the basic fire drill procedure.

"The cabin crew located the source of the smoke... and removed the seat cushions and covers from seat 19F while the customer services manager (CSM) turned off the power to the centre column of the seats.

"When the seat was further dismantled, the crew found a crushed personal electronic device (PED) wedged tightly in the seat mechanism. The cabin crew assessed that the crushed PED contained a lithium battery."

Aircraft seats are fire retardant by law but will not prevent smoke produced by a lithium-ion battery overheating from short-circuiting.

Consequently "a strong acrid smell remained in the cabin" even after the offending item was retrieved.

The guilty mobile phone was then placed in a jug of water before being placed in a metal box and monitored for the rest of the flight.

Needless to say it did not survive the mishap and all that remained was a twisted lump of melted metal.

No one was injured in the incident and the ATSB said the crew had responded well, stating: "This incident provides an excellent example of an effective response to an emergency situation."

Consequently the flight was only two hours late to Dallas, Texas.

However, losing a phone in such a way will only really pose a problem on long-haul flights in business class when passengers' phones can slip down the side of a chair and get crushed when the seat is elongated into a bed.