Interference from a defence communications base may have caused a Qantas flight to plunge suddenly last month, injuring 44 passengers and crew.
A preliminary report into the incident by the Australian Transport Safety Bureau says it is possible that transmissions from the Harold E Holt naval communications station interfered with onboard aircraft systems.
It is also investigating the possibility that passengers' electronic devices aboard the aircraft caused the problem.
The incident occurred as a Qantas Airbus A330 was flying off the West Australian coast en route from Singapore to Perth.
Forty-four of the 313 people on board required hospital treatment after the aircraft suddenly plunged, hurling passengers around the cabin.
