Bad weather and poor underwater visibility have prevented Indonesian navy divers from searching inside the large chunk of AirAsia jet wreckage that is believed to be the fuselage.

At least 15 divers descended to the seabed at a depth of 92ft to examine the piece of wreckage spotted yesterday, calculate its weight and search for bodies.

They were unable to do so because of the weather and sea conditions, said Suryadi Bambang Supriyadi, the operation director at the National Search and Rescue Agency.

He said it appeared that some parts of the fuselage are covered with silt. If bodies are found, the divers will try to put them in individual body bags, which rescuers on ships would then hoist to the surface, he said.

The 100ft section of the plane body with a wing attached was sighted on the bottom of the Java Sea by a Singaporean navy ship.

Only 50 bodies have been recovered since the plane disappeared from radar and crashed in the sea on December 28 en route from Surabaya, Indonesia, to Singapore. Most of the 162 victims were Indonesian.

Rescuers believe most of the bodies are inside the main fuselage.

Search and Rescue Agency chief Henry Bambang Soelistyo said the large piece of wreckage would be lifted from the seabed after the search for bodies was no longer considered effective.

The plane's flight data and cockpit flight recorders were retrieved earlier this week and will be key to learning the cause of the crash. Bad weather is a suspected factor.

Nine aircraft and 10 ships are still conducting search operations. Two US ships and one from Singapore have left, Mr Soelistyo said.