JAKARTA - Multinational search teams hunted Monday for any sign of an AirAsia plane missing off Indonesia with 162 people on board, but one top official warned it was likely at the bottom of the sea.
Australia, Singapore and Malaysia deployed planes and ships to assist in the search as anguished relatives anxiously waited for news of their loved ones more than a day after Flight QZ8501 disappeared over the Java Sea.
The Airbus A320-200 lost contact en route from Surabaya in Indonesia's east Java to Singapore on Sunday after the crew requested a change of flight plan due to stormy weather, in the third crisis for a Malaysian carrier this year.
"Based on the coordinates given to us and evaluation that the estimated crash position is in the sea, the hypothesis is the plane is at the bottom of the sea," National Search and Rescue Agency chief Bambang Soelistyo told journalists.
"That's the preliminary suspicion and it can develop based on the evaluation of the result of our search," he said.
Currently search teams are scouring an area where the sea is 40-50 metres (130-160 feet) deep, he said, adding that Indonesia was coordinating with other countries to access any equipment that may be needed to scour the sea bed.
"Due to the lack of technology that we have, I have coordinated with our foreign minister so we will borrow from other countries which have offered. They are the UK, France and US," he said.
"It is not easy to look for something underwater.... That will not break our spirit to continue searching, no way."
Hoping for news
Distraught relatives spent the night in Surabaya hoping for news of their loved ones as international teams expanded their search area for the lost plane.
Vicky said he had not given up hope of finding his two siblings who were on the flight, and criticised an airline official who said he shared the families' "sadness" at the plane's disappearance.
"What he said was not appropriate at all. If they were sad it means there's death. But the flight has not been found yet," he told AFP.
AirAsia said 155 of those on board flight QZ8501 were Indonesian, with three South Koreans and one person each from Singapore, Malaysia, Britain and France. The Frenchman was the co-pilot.
Air traffic controllers lost contact with the twin-engine aircraft around an hour after it left Surabaya's Juanda international airport at about 5:35 am (2235 GMT Saturday).
Shortly before disappearing, the pilot asked to ascend by 6,000 feet to 38,000 feet to avoid heavy clouds, according to an Indonesian transport ministry official.
"But their request to fly to 38,000 feet from 32,000 feet could not be approved at that time due to traffic, there was a flight above, and five minutes later the flight disappeared from radar," Djoko Murjatmodjo told a press conference Sunday.
The search is focused on waters around the islands of Bangka and Belitung in the Java Sea, across from Kalimantan on Borneo island, but the army has also been asked to carry out ground searches, including in mountainous areas.
Soelistyo said the search area had been expanded northwards in the waters between Sumatra and Kalimantan.
"We added three sectors to the north of the (four) search areas we had yesterday," he said.
"We are looking around Bangka Belitung islands, Singkep, Karimata strait, as well as the land area west of West Kalimantan." A Royal Australian Air Force AP-3C Orion equipped with sophisticated search equipment took off from the northern Australian city of Darwin while Singapore said it was deploying two C-130 aircraft in addition to naval ships already dispatched.
'Praying for safety'
The missing plane was operated by AirAsia Indonesia, a unit of Malaysian-based AirAsia, which dominates Southeast Asia's booming low-cost airline market.
Indonesia said it would review the company's operations.
"We will do a ground check as well as a review of AirAsia's operations in Indonesia to ensure that all of its activities are better in the future," Transport Minister Ignasius Jonan told reporters.
Indonesia, a vast archipelago with poor land transport infrastructure, has seen explosive growth in low-cost air travel over recent years.
But the air industry has been blighted by poor safety standards in an area that also experiences extreme weather.
AirAsia, which has never suffered a fatal accident, said the missing jet last underwent maintenance on November 16.
Its shares fell 12 per cent at the open in Kuala Lumpur but recovered slightly to sit at 2.71 ringgit, down 7.82 per cent.
The plane's disappearance comes at the end of a disastrous year for Malaysian aviation.
Malaysia Airlines Flight MH370 disappeared while flying from Kuala Lumpur to Beijing in March with 239 passengers and crew, and in July flight MH17 was shot down over troubled Ukraine killing all 298 on board.
Indonesia's President Joko Widodo said his nation was "praying for the safety" of those onboard. Vice President Jusuf Kalla was due to visit Surabaya Monday afternoon to meet relatives of those missing.