Air Asia flight crash recovery
Indonesian Navy ship KRI Yos Sudarso takes part in the search operation for missing AirAsia Flight QZ8501, as seen from an Indonesian Hercules aircraft, south of Pangkalan Bun, central KalimantanAntara Photo Agency via Reuters

Indonesian officials have revealed the fuselage of AirAsia flight QZ8501 is lying upside down on the ocean floor as the recovery operations are being hampered by bad weather.

The Search and Rescue agency said the sonar images show the plane is sitting upside down as authorities switch their attention to the flight data recorders to determine the cause of the crash.

The image was taken by an Indonesian naval vessel which is participating in the search operation.

On Wednesday, the fourth day of the search, authorities recovered three more bodies, taking the total to six. One of the bodies is suspected to be that of a crew member.

The possibility that the plane exploded in mid-air has been largely ruled out by experts, as there are no burn injuries on the bodies of the victims and the corpses are mostly fully clothed.

The Airbus A320-200, which was travelling from Indonesia to Singapore and carrying 162 people, lost contact with ground authorities 42 minutes after take-off. The last communication from the pilot was a request for higher altitude due to bad weather but this was denied due to congestion in the air.

Though the waters are shallow at the crash zone, high waves are currently hampering the recovery measures and winds are preventing divers from pressing on with the operation.

Singaporean navy personnel have also arrived at the site and are set to coordinate the recovery.

"Weather conditions are not ideal, but we will continue to push," LTC Ang, commanding officer of Singaporean vessel RSS Persistence, was quoted as saying.