JAKARTA – A US warship on Tuesday joined an expanded search for an AirAsia passenger plane missing off Indonesia as the pilot's last words to air traffic control were revealed.
The recording shows the pilot wanted to avoid a menacing storm system before all communication was lost, an Indonesian air safety official said.
More than 48 hours after the Airbus A320-200 carrying 162 people lost contact en route from Indonesia's second largest city Surabaya to Singapore, no clue has been found as to the plane's final location or fate.
Before take-off the pilot had asked for permission to fly at a higher level to avoid a storm but his request was not approved due to heavy traffic on the popular route, AirNav, Indonesia's flight navigation service, said on Tuesday.
In his final communication, the pilot asked to alter his course and repeated his original request to ascend to avoid bad weather.
"The pilot requested to air traffic controllers to deviate to the left side due to bad weather, which was immediately approved," Wisnu Darjono, the safety director for Indonesia's flight navigation service AirNav said.
"After a few seconds the pilot requested to ascend from 32,000 to 38,000 feet but could not be immediately approved as some planes were flying above it at that time," Darjono said.
That was the last communication with AirAsia Flight QZ8501.
"Two to three minutes later when the controller was going to give a clearance to a level of 34,000, the plane did not give any response," he said.
At take-off the pilot had requested permission to fly at 34,000 feet but due to traffic it could not be approved, he said.
"At that time there were 11 planes flying route M635," he said, adding that 160 flights a day used the route to Singapore.
No sign of aircraft
Details of the pilot's final contact came as the National Search and Rescue Agency (Basarnas) said it had expanded the search.
The hunt 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.
Basarnas chief Bambang Soelistyo told reporters the search zone had been expanded from seven sectors to 13, covering 156,000 square kilometres.
"We intensified today's search operation by expanding the search area on sea from the coordinates where the plane was missing and on land to the east and west of Borneo island," deputy operations chief Tatang Zainuddin said.
As the search resumed at dawn for a third day, he said oil spills spotted on Monday had been tested but were not aviation fuel.
"The oil leak is actually from fishermen's boats, not from the AirAsia plane," Zainuddin said.
"We haven't found any signs of the aircraft's whereabouts up to now." Indonesian officials however appear to be preparing for the worst, with Soelistyo saying on Monday it was likely the plane was at "the bottom of the sea," based on its estimated position.
Australia, Singapore and Malaysia have sent maritime surveillance aircraft and warships to assist in the search, joining Indonesian planes, ships and scores of fishing boats scouring the waters for signs of the ill-fated aircraft.
Washington said it was deploying the USS Sampson to join the growing international effort, with the destroyer expected to arrive in the search zone on Tuesday.
South Korea said it was sending a P-3 reconnaissance plane that was involved in the search for Malaysia Airlines Flight MH370 which vanished in March.
While the operation has drawn comparisons with the ongoing search for MH370, Australian Prime Minister Tony Abbot said it did not appear to be a great mystery.
"It doesn't appear that there's any particular mystery here," Abbott told Sydney radio station 2GB on Monday.
"It's an aircraft that was flying a regular route on a regular schedule, it struck what appears to have been horrific weather, and it's down. But this is not a mystery like the MH370 disappearance and it's not an atrocity like the MH17 shooting down." China, which had 152 citizens onboard MH370, said it was sending a frigate and military aircraft to help with the new search.
AirAsia said 155 of those on board were Indonesian, with three South Koreans and one person each from Singapore, Malaysia, Britain and France. The Frenchman was the co-pilot.
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, a vast archipelago with poor roads and railways, has seen explosive growth in low-cost air travel over recent years.
But the air industry has been blighted by low 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.
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 unrest-hit Ukraine, killing all 298 on board. — AFP