Fresh detail has surfaced from the ill-fated Singapore-bound AirAsia flight QZ8501 which crashed in the Java Sea on Dec 28, killing all 162 passengers and seven crew.

New extracts of communication audio between Surabaya Air Traffic Control (ATC) Juanda International Airport and the captain revealed clues that flight QZ8501 was authorised to fly on the Surabaya-Singapore route, as reported by news portal, KompasTekno.

Initially, KompasTekno obtained the recording via Soundcloud by adopting user-ID “digitising” on January 3, 2014 soon after Indonesia’s Ministry of Transportation halted the Surabaya-Singapore route for AirAsia.

Insiders from KompasTekno (who preferred anonymity) have confirmed that the recording was the authentic recording by Juanda Airport ATC on Sunday (Dec 28, 2014). The matter was further verified from the other air traffic activities monitored on the morning of the tragedy.

The file was recorded in UTC format (or Zulu time: GMT + 0) on Dec 27, 2014 at 22.25, which means the date was Dec 28, 2014 (5.25am) East Indonesia time (WIB).

During the 20-minute computer-generated audio recording, a voice believed to be emitted from flight QZ8501 (with the call sign Wagon Air8501) was heard during the tenth-minute of the clip informing its position on hangar A9 which boasted the registration PK-AXC (Alpha X-ray Charlie), total number of passengers and the purpose to Singapore.

The conversations (in a verbatim) are as follows:

AWQ8501: "Tower, Wagon Air eight five zero one good morning..."
Tower: "Wagon Air 8501 good morning Juanda Tower, go ahead..."

AWQ8501: "Eight five zero one (registrasi) alpha x-ray charlie parking stand Alpha Niner (A9) destination Singapore POB (passenger on board) one six one, request push and start, wagon air eight five zero one..."

Tower: "Wagon Air eight five zero one parking stand number Alpha niner Pushback and start approved heading west runway one zero, exit sierra two...

Shortly after, at approximately the fourth minute, flight QZ8501 sought approval from ATC to proceed to the runway. ATC directed QZ8501 to runway 10 which the flight was placed on standby.

At 07.07 minute, ATC authorised clearance for takeoff via M635 airways at the height of 24,000-feet.

"Wagon Air eight five zero one clear to Singapore, mike six three five level two four zero initial, RAMPY one alpha departure squawk number seven zero zero five,” a female voice from the ATC was heard.

[LISTEN to the communication recording on Soundcloud HERE]

Logically speaking, if ATC has issued an authorisation, the flight plan agreed upon, it can only be executed and agreed, if permission is obtained, granted there are slots available at both departure and arrival airports.

Understandably, if ATC has issued its permission, AirAsia would have gotten the clearance to fly, just as how the Singapore counterpart had mentioned as the flight's immediate destination.

Civil Aviation Authority of Singapore (CAAS) on its website stated that AirAsia flight QZ8501 has obtained its flight schedule from Surabaya to Singapore on Sunday (Dec 28, 2014)

According to CAAS, the route approval from Surabaya’s Juanda Airport in Indonesia to Changi Airport in Singapore for flight QZ8501 on the incident day was made based on an agreement between the two countries.

CAAS reaffirmed that the Indonesia-Singapore pact concerning the flight schedule started since October 26, 2014 until March 6, 2015.

This matter was raised by Juanda Airport authority chief Praminto Hadi who had previously stated that AirAsia did not obtain official permission to fly on December 28, 2014.

“AirAsia did not make any amendment in its flight plan from Saturday to Sunday to the Air Communication director-general which led to its unathourised flight on Sunday,” said Praminto at the Mapolda Complex in East Java, Monday.

The ill-fated aircraft went down during a flight from Surabaya, Indonesia’s second largest city en route Singapore on December 28 when it was reportedly crashed 40 minutes after it took off. The flight did not emit a distress signal before it disappeared from radar screens.

[PHOTO GALLERY]: BLACK DAY FOR QZ8501 FAMILIES AS BODIES FOUND IN SEA

It still remains a mystery what caused the crash despite a massive search for the main part of the plane which has not been recovered. The plane was carrying 137 adult passengers, 17 children and one infant, two pilots and five crew - the majority Indonesians.

The massive search operations, Wednesday enter its 11th day as hunt areas are expanded.