Navigation Error Send AirAsia Sydney-KL Flight to Melbourne

7th Sep 2016

AirAsia flight on 10^th March last year from Sydney to Kuala Lumpur went the wrong way and ended up in Melbourne because the Airbus A330 pilot entered the wrong coordinates in the planes navigation system, found the air safety inspectors investigating this curious case.

That’s a long way to go, considering Melbourne Airport is 722 kilometers SE of Sydney and KL is 6,611 km to the NW.

According to the investigators, the A330 crew ignored the chimes from the computer system, so this, together with entering wrong data and the poor weather on that day in Sydney all caused the plane to land in Melbourne.

The plane was scheduled to depart Sydney airport at 11:55 am and to arrive in KLIA in Malaysia about nine hours later. It instead arrived in Melbourne at around 2:00 pm.

The Australian Transport Safety Bureau (ATSB) said in its report that the problem transpired when the captain and the 1^st officer had to swap their usual pre-flight checks due to some faulty earmuffs. In normal circumstances, ATSB report says, the captain would inspect the plane, while the 1^st officer would remain in the cockpit and complete the necessary procedures there.

This time, however, the captain had to take over the cockpit. When he was entering the longitude in the system he entered it as 151° 9.8’ east, or 15109.8, while it should have been 15° 19.8’ east, or 01519.8.

According to the ATSB report, the crew still had “a number of opportunities to identify and correct the error”, including a flag flashing on the captain’s screen during crosscheck of the cockpit preparations. The message, however, was not mentioned by the first officer, as it was “too quick to interpret”. Additionally, there were also three other chimes, but these were ignored as they were not accompanied by a message from the onboard computer.

The crew noticed the mistake only once they took off and started going in the wrong direction. Only after the autopilot engaged at 410 feet and veered the plane in the direction of another runway (Melbourne) did the captain and the 1^st officer attempt to fix the mistake. However, their “attempts to troubleshoot and rectify the problem resulted in degradation of the navigation system, as well as to the aircraft’s flight guidance and flight control systems”, said ATSB.

Once the plane landed in Melbourne, it spent around three hours on the ground there fixing the navigation problem before leaving for KL. It finally landed at Kuala Lumpur International Airport six hours behind scheduled time, at 10:20 pm.