Other, Batik Air Indonesia (Airbus A320 Pk-Luv) Enroute From Kdi to CGK, KNKT.24.01.02.04

On 25 January 2024, an Airbus A320 aircraft registered PK-LUV was being operated as scheduled passenger flight from Soekarno-Hatta International Airport (WIII), Jakarta to Halu Oleo Airport (WAWW), Kendari and return. The aircraft was operated by two pilots and four flight attendants.

The first flight from Jakarta departed at 0314 LT (2014 UTC). The Pilot in Command (PIC) acted as pilot flying (PF) and the Second in Command (SIC) acted as pilot monitoring (PM).

At 0711 LT (2311 UTC), the aircraft landed Kendari using Runway 26 and parked at the apron. During this transit, both pilots eat instant noodle cups in the cockpit.

At 0805 (0005) UTC, the aircraft departed from Kendari to Jakarta. In this flight, the PIC acted as PM and the SIC acted as PF. The total number of passengers on board was 153.

At 0037 UTC, the aircraft reached the cruising altitude of 36,000 feet. After maintaining the cruising altitude, both pilots took their headsets off and the cockpit loudspeaker volume was increased. The PIC then asked permission to rest from the SIC and was granted. A few seconds later, the PIC slept and the SIC then took over the PIC duty as PM.

The PIC woke up and at 0122 UTC, asked whether the SIC wanted to rest. The SIC responded that he did not want to rest. Both pilots then had a non-related-duty conversation for about 30 seconds and then the PIC continued to sleep. The SIC was aware that the PIC was sleeping and continued the duty both as PF and PM.

At 01:43:32 UTC, the SIC made initial contact with the air traffic controller of Jakarta Area Control Center (ACC). BTK6723 was instructed to follow KURUS 2G Standard Instrument Arrival (STAR) and report when the aircraft was clear from bad weather conditions. At that time, the aircraft was flying on a heading of 250° to avoid bad weather condition, and position was about 125 Nm from Waypoint KURUS. A few moments later, the SIC inadvertently fell asleep.

Jakarta ACC called BTK6723 several times and there was no response from the pilots.

At 0211 UTC or 28 minutes after the last recorded transmission from the SIC, the PIC woke up and was aware that the aircraft was not in the correct flight path. The PIC then saw the SIC was sleeping and woke him up. About the same time, the PIC responded to the call from another pilot and Jakarta ACC. The PIC advised the Jakarta ACC that BTK6723 experienced radio communication problem and currently the problem has been resolved. The flight then continued and landed at Jakarta uneventfully.

The investigation concluded several contributing factors based on the safety issues identified following the serious incident.

The KNKT acknowledges the safety actions taken by the aircraft operator and considered that the safety actions were relevant to improve safety, however there still safety issues remain to be considered. Therefore, the KNKT issued safety recommendations to address safety issues identified in this report.