What happened
On 20 November 2013, a runway incursion occurred at Adisutxipto International Airport involving two commercial aircraft. An Airbus A320, operated by Indonesia Air Asia (registration PK-AWQ), was taxiing toward the holding point for runway 27. During the taxi process, the flight crew requested a route via taxiway N3, but the tower controller reconfirmed a route via N2. The crew misinterpreted this clearance, believing the holding point was located on taxiway N3 near the runway threshold.
Simultaneously, a Boeing B737-900ER, operated by Batik Air (registration PK-LBH), was on final approach. As the Airbus A320 entered the runway, the pilot noticed the approaching aircraft and immediately applied brakes and reverse thrust to stop. The Boeing B737-900ER touched down and, upon seeing the stationary aircraft on the runway, applied maximum braking and reverse thrust. The aircraft stopped approximately 100 meters from the Airbus A320, preventing a collision.
The investigation
The investigation by the KNKT focused on the breakdown in coordination between the Yogya Approach and Adi Tower controllers. It was established that the landing clearance for the Batik Air flight was issued by the Approach controller, who advised the crew to contact the Tower only after landing. Consequently, when the Tower controller attempted to instruct the Boeing B737-900ER to perform a go-around, the crew did not acknowledge the instruction because they were still monitoring the Approach frequency.
Investigators also examined the taxi clearance process, finding that the discrepancy between the requested taxiway (N3) and the assigned taxiway (N2) was not sufficiently clarified between the pilot and the controller. Furthermore, the investigation noted that the N3 taxiway was being used under trial conditions and had not yet been updated in the official Aeronautical Information Publication (AIP).