PANGKALAN BUN, Jan 9 (Reuters) - Indonesian search teams loaded lifting balloons on to helicopters on Friday ahead of an operation to raise the tail section of an AirAsia jet off the sea bed, raising hopes the black boxes can be found to reveal the cause of the disaster.
Indonesia AirAsia Flight QZ8501 vanished from radar screens on Dec. 28 less than half way into a two-hour flight from Indonesia's second-biggest city of Surabaya to Singapore.
There were no survivors among the 162 people on board.
The Airbus A320-200 carries the black box cockpit voice and flight data recorders near the tail section. Officials have warned, however, that they could have become separated from the tail.
The tail was found on Wednesday, upturned on the sea bed about 30 km (20 miles) from the plane's last known location at a depth of around 30 metres.
"For today's operations, we will use helicopters to carry the balloons that will assist in lifting the tail," Lt Col Penerbang Jhonson Hendrico Simatupang told Reuters.
He said the weather was fine on Friday morning.
"But we are expecting sudden changes later in the day," he said. "So we're taking advantage now and moving the balloons as fast as we can."
The head of Indonesia's search and rescue agency, Fransiskus Bambang Soelistyo, said in Jakarta on Thursday that a crane might also be used to lift the tail.
Relatives of the victims have urged authorities to make finding the remains of their loved ones the priority.
Ships with acoustic "pinger locators" designed to pick up signals from the black boxes were at the location but were no longer being used, in a possible sign of confidence among Indonesian officials that the recorders will be found soon.
According to Nurcahyo Utomo, an investigator at the National Transportation Safety Committee (NTSC), the time taken to analyse what happened to the flight depended partly on the condition of the recorders.
The NTSC is leading the probe, with France's BEA crash investigation agency officially participating.
Forty-four bodies and debris from the plane have been plucked from the surface of the waters off Borneo, but strong winds and high waves have hampered efforts to reach larger pieces of suspected wreckage detected by sonar on the sea floor.
Indonesia AirAsia, 49 percent owned by the Malaysia-based AirAsia budget group, has come under pressure from the authorities in Jakarta since the crash.
The transport ministry has suspended the carrier's Surabaya-Singapore licence, saying it only had permission to fly the route on Mondays, Tuesdays, Thursdays and Saturdays.
Flight QZ8501 took off on a Sunday, though the ministry said this had no bearing on the accident.
While the cause of the crash is not known, the national weather bureau has said seasonal tropical storms common in the area were likely to be a factor.
Additional reporting by Nicholas Owen, Michael Taylor, Eveline Danubrata, Gayatri Suroyo, Wilda Asmarini, Nilufar Rizki and Charlotte Greenfield in Jakarta; Writing by Nick Macfie