Authorities in Jakarta have said Indonesia AirAsia violated the terms of its licence for the Surabaya-Singapore route by flying on a Sunday, the day the carrier's Airbus A320-200 plunged into the Java Sea.
Djoko Murdjatmodjo, acting director general of air transportation, on Saturday said, "We will investigate all AirAsia flight schedules. Hopefully we can start next Monday. We won't focus on licences, just schedules…It is possible AirAsia's licence in Indonesia might be revoked."
Sunu Widyatmoko, Indonesia AirAsia chief, told reporters the airline, 49-per cent owned by Malaysia-based AirAsia, would cooperate with the inquiry. "The government has suspended our flights from Surabaya to Singapore and back…It is doing the evaluation process. AirAsia will cooperate fully."
On Friday, Indonesian authorities questioned whether the pilot had followed correct weather report procedures. Subsequently, they suspended Indonesia AirAsia's Surabaya-Singapore flights for apparently infringing the terms of the carrier's licence for the route.
Indonesia's transport ministry said the terms of Indonesia AirAsia's licence for the Surabaya-Singapore route permitted flights on four days of the week. These, it added, didn't include Sundays. "As of January 2, the licence of Surabaya-Singapore (return) route to Indonesia AirAsia is temporarily frozen until the evaluation and investigation leads to a result," said spokesman Julius Adravida Barata.
Hadi Mustofa Djuraid, a transport ministry official, said authorities were also investigating the possibility that the pilot didn't seek a weather report from the meteorological agency at the time of take-off.
According to Indonesia AirAsia, the Indonesian pilot, a former air force fighter pilot, had 6,100 flying hours on the A320 and the plane had last undergone maintenance in mid-November.
Meanwhile, search teams hunting for the wreck of the AirAsia passenger jet that crashed with 162 people on board had found four large parts of the plane on the sea bed, Fransiskus Bambang Soelistyo, head of Indonesia's search and rescue agency, said on Saturday.
A multinational task force of ships, planes and helicopters has been scouring the northern Java Sea and the coastline of southern Borneo to recover the bodies of victims and locate the wreck of flight QZ8501 and its black-box flight recorders.
No survivors have been found from the crash, which took place about 40 minutes after the plane took off from Indonesia's second-largest city, in an area known for intense tropical thunderstorms. Air traffic controllers lost contact with flight QZ8501 minutes after the pilot requested to fly higher to try and avoid a storm.
Recovering victims
Much of the effort has focused on finding the victims of the crash. Officials said 21 bodies were pulled from the sea on Friday, including two still strapped to their seats, bringing the total number of victims recovered to 30.
Small pieces of the aircraft and other debris have also been found. However, there has been no sign of the crucial black box - the voice and flight data recorders - that investigators hope will unravel the sequence of events in the cockpit during the doomed jet's final minutes.
"We've found four big parts from the plane we're looking for," Soelistyo told reporters in Jakarta. One large object was pinpointed by a ship searching during the night, he said, adding three more, the largest of which was about 18 metres long, were located on Saturday.
Operating underwater remote operating vehicles was a challenge, Soelistyo said. "The visibility is only two metres…It's cloudy, making it difficult for the cameras to detect."
Divers, including a team of Russian specialists who just arrived in Pangkalan Bun, might be able to investigate the suspected wreckage on Sunday if the weather improved, officials said.
The cause of the crash, the first recorded by the AirAsia group since the budget carrier began operations in 2002, is unexplained. The plane was flying at 32,000 ft (9,753 metres) and the pilot had sought permission to climb to 38,000 ft just before contact was lost. When air traffic controllers granted permission to fly at 34,000 ft a few minutes later, there was no response.
A source privy to the investigation said radar data appeared to show the aircraft made an "unbelievably" steep climb before it crashed, possibly pushing it beyond the A320's limits.