On 25 November 2011, a Saab Aircraft Company S340B was being operated on a scheduled passenger service from Lismore to Sydney, New South Wales (NSW). During the taxi to the gate after arrival at Sydney, a cabin crew member noticed smoke coming from near a passenger seat and instructed the passenger to throw the source of the smoke into the aisle. The cabin crew member then discharged a fire extinguisher onto what was later identified as a mobile telephone. After several minutes, the smoke cleared.
An Australian Transport Safety Bureau (ATSB) investigator travelled to Sydney airport to commence an investigation into the event. The mobile telephone was transported to the ATSB technical facilities in Canberra for initial examination and then forwarded to the United States for detailed examination at a specialist facility.
The technical examinations found that a small metal screw had been misplaced in the battery bay of the mobile telephone; the screw puncturing the battery casing and causing an internal short circuit leading to heating and thermal runaway. It was probable that the screw had been misplaced during an earlier repair carried out on the telephone. That repair had not been conducted by an authorised service provider.
This investigation highlights the risks associated with the use of non-authorised agents for the repair of lithium battery-powered devices, and reinforces the Civil Aviation Safety Authority (CASA) recommendations that these devices should be carried in the cabin and not in checked-in baggage.