Investigations have begun into a mid-air incident involving a Boeing 747, owned by Australian airline Qantas, on a flight from London to Bangkok.
Qantas has confirmed that flight QF2, carrying more than 300 passengers was 15 minutes from Bangkok on Monday, when it lost all electrical power, and was forced to use its backup battery system.
The flight landed safely without further incident.
A Qantas spokesman says the power failure has been reported to Boeing, the Australian Transport Safety Bureau and the Civil Aviation Safety Authority.
The Transport Safety Bureau says it expects Thai authorities to conduct a full investigation.
Qantas is also conducting its own investigations with the aircraft being assessed and repaired in Bangkok.