The pilot of an Indonesia Air Asia A320 flying from Perth to Bali programmed in the wrong runway into the plane’s computer, which resulted in a sudden left turn after take-off Australia’s crash investigator has found.

In its preliminary report released this morning the Australia Transport Safety Bureau said that on November 24 2017, at about noon the crew of an Airbus A320 aircraft, registered PK-AZE and operated by AirAsia Indonesia as flight QZ535, was being prepared to depart on a scheduled passenger service from Perth Airport, Western Australia for Denpasar Airport, Indonesia.

The captain was designated as the pilot monitoring and the first officer (FO) was designated as the pilot flying.

The ATSB said that while the captain was conducting the pre-flight walk around, the FO entered the flight plan into the flight management guidance computer (FMGC).

“Believing that they would be using runway 03 for take-off, as they had recently landed on this runway, he entered this into the FMGC,” the report said.

However, he then listened to the automatic terminal information service, (ATIS) which indicated the runway-in-use was in fact runway 21 - same runway but the opposite direction to the south.

When the captain returned to the flight deck, the FO completed the pre-flight and departures briefing using runway 03.

At 12.01pm, the crew received their clearance from air traffic control for a standard departure south on the runway heading of 210 and to climb to 5,000 ft.

At 12.13pm the crew commenced taxiing.

The crew also received ATC clearances to taxi to, and line-up on runway 21, which was read back correctly by the crew.

At 12.20pm the A320 took off from runway 21.

Shortly after take-off, the aircraft was turned left at 260 ft above mean sea level (AMSL) which was contrary to the departure procedure and below the minimum safe altitude stipulated by the operator.

The ATSB found that after observing the aircraft turning left on radar, ATC re-cleared the crew onto an assigned radar heading.

The crew then reported operations normal and the aircraft was turned to intercept the flight planned route and continued to Denpasar without further incident.

The investigation is ongoing.

The incident is similar to another in 2015 involving Air Asia X in Sydney. In that incident the captain entered the wrong longitude into an Airbus A330’s navigation system, making the plane’s computer believe it was 11,000km from its location at Sydney Airport.

The bungle caused the Air Asia X plane to fly in the wrong direction and across the departure path of an adjacent runway.

An AirAsia Group spokesperson said: Safety is always our number one priority and underpins the operation at all times.  As part of our commitment to always putting safety first, the airline immediately put in place a number of measures to address this incident, in the areas of operational standards and flight crew training following the airline's own independent investigation of the incident.  AirAsia will continue to provide full cooperation to the ATSB with its ongoing investigation.  As the review is ongoing by AirAsia, the ATSB and other relevant authorities, we are unable to comment further on the details at this time.