The search for AirAsia flight QZ8510 which crashed into the sea on Sunday is set to move underwater, with the arrival of specialist equipment.
A French crash investigation team will use sensitive acoustic detection devices to try locate the plane’s “black box” flight recorder.
The Airbus A320-200 was flying from Surabaya in Indonesia to Singapore with 162 people on board when it vanished.
No survivors have been found and the cause of the crash remains unknown.
Several more bodies were located on Friday, bringing the total found to 16.
One person has been identified as passenger Hayati Lutfiah Hamid – her funeral was held in Surabaya on Thursday.
The plane is almost certainly at the bottom of the relatively shallow Java Sea.
Several pieces of debris have been recovered, including what is thought to be part of a wing flap.
But despite a massive five-day search the fuselage is still missing. Officials say most of the passengers could still be inside.
The BBC’s Rupert Wingfield-Hayes in Pangkalan Bun on the Borneo coast – the nearest town to the suspected crash site – said there is a growing sense among search teams that their task is going to be harder than initially thought.
Bad weather and churning seas have dashed hopes of finding the plane visually, he says, and teams will now be relying on the sonar and listening equipment to scan the sea floor.
Locating the fuselage and the flight recorder will help answer the mystery of what happened to make the plane fall from the sky.
The head of Indonesia’s search and rescue agency, Bambang Soelistyo, said on Friday that wreckage and bodies are spread over a 5km area of the Java Sea.
The search was now focussing on an area of 1,575 nautical square miles of the Java Sea off Borneo, he told reporters.
“Divers are already on standby at the navy ship Banda Aceh to dive on that priority area to locate the body of the plane,” he said. “I hope we’ll get a significant result today.”
‘Unbelievably steep climb’
There were 137 adult passengers, 17 children and one infant, along with two pilots and five crew, on the plane. The majority of those on board were Indonesians.