Indonesian authorities found that a Captain and First Officer fell asleep for almost 30 minutes on a Batik Air domestic flight.

Asleep at the Controls

On January 25, a Batik Air Airbus A320-200, registered PK-LUV, took off from Jakarta's Soekarno-Hatta International Airport (CGK) for a domestic flight to Kendari Haluoleo Airport (KDI). The leg from Jakarta to Kendari operated as Flight BK-6724. This flight has a very early scheduled departure time of 2:55 a.m. local time, landing in Kendari at 7:10 a.m. Kendari's local time is one hour ahead of Jakarta's, and the CGK-KDI flight takes roughly three hours.

It's worth noting that despite being a domestic flight, Indonesia is a vast country. Jakarta is on Java island, while Kendari is in Southeast Sulawesi. According to the Indonesian National Transport Safety Committee's preliminary report, the First Officer of Flight 6724 notified the Captain that he did not receive proper rest.

Shortly after the flight reached its cruising altitude of 36,000 feet (10,973 meters), the Captain offered the First Officer to rest, which he did for 30 minutes. It was reported that the First Officer woke up shortly before the aircraft began its descent. Flight 6724 landed safely in Kendari. During the turnaround, the preliminary report notes that the pilots did not perform out of the ordinary and ate instant noodle cups in the cockpit.

The return flight to Jakarta, Flight BK-6723, departed on time for its two-hour and 40-minute flight back westward. There were 153 passengers onboard. The aircraft soon reached its cruising altitude of 36,000 feet (10,973 meters). This was reported around 12:37 a.m. UTC. Shortly after, the Captain asked permission from the First Officer to take some rest. The First Officer agreed, and the Captain fell asleep.

A short while later, the Captain woke up at 1:22 a.m. UTC and asked the First Officer if he wanted to rest, to which the First Officer rejected the offer. The First Officer spent the next 20 minutes communicating with Air Traffic Control (ATC) and the flight attendants. According to the report, he contacted Jakarta ATC at 1:43:32 a.m. UTC regarding the aircraft's arrival procedure.

Jakarta ACC instructed BK-6723 to follow the KURUS 2G Standard Instrument Arrival (STAR) and report when the flight was clear of bad weather conditions. At 1:43:42 a.m. UTC, the First Officer returned Jakarta ATC's instructions. This was the last recorded transmission from BK-6723 before the First Officer fell asleep as well.

What Happens Next?

At 1:56 a.m. UTC, 12 minutes after the last recorded transmission from the First Officer, Jakarta ACC radioed BK-6723 asking how long the flight would need to fly on its current heading of 250 degrees. There was no response from the pilots. Jakarta ACC repeated attempts to contact the flight, even asking other aircraft in the area to contact BK-6723. None of these calls received a response. 

Finally, at 2:11 a.m. UTC, the Captain woke up 28 minutes after the last recorded transmission only to find that his aircraft had flown off-course. He woke the First Officer up and then began responding to a call from another pilot and Jakarta ACC. The Captain advised Jakarta ACC that his aircraft had experienced a radio communication problem, which had been resolved.

When looking at playback data from Flightradar24, the A320 was well off-course at this point. The flight passed to the southeast of Jakarta, near Bandung. This was a significant distance from KURUS, the waypoint the flight was supposed to fly towards before it arrived in Jakarta. At 2:12 a.m. UTC, the pilots sharply turned towards Jakarta and the KURUS waypoint. The flight landed safely on CGK Airport's Runway 25L, a few minutes behind schedule.

What Do Airlines Say?

Batik Air Indonesia's Operation Manual explains the following regarding fatigued crewmembers:

"[The crew member] is not [to] operate the flight if he is fatigued, or if in his opinion his physical, emotional or wellbeing would render him unfit or unsafe during any part of his flight duty period. In this case, the pilot must advise [the] Fleet Chief Pilot or his deputy, and for Flight Attendants, [they] must advise [the] Chief FA Assistant for Daily Operations at [the] first possible opportunity."

Many long-haul flights have relief pilots to ensure that each pilot is sufficiently rested when they assume control of the aircraft. Furthermore, most widebody aircraft feature dedicated crew rest areas where crewmembers can sleep for a few hours during their time off. Aircraft without dedicated crew rest areas usually have seats in the cabin blocked off.

That is the case on narrowbody or other short-haul flights. Otherwise, the pilots can engage in a "controlled rest period." These involve one pilot briefly catching some sleep while the other continues to monitor the controls. This scenario was present on the outbound leg to Kendari. Such controlled rest periods are designed to help manage fatigue.

Batik Air said in a statement that it "operates with adequate rest policy," despite the First Officer saying that he had not rested sufficiently the night before the trip. The preliminary report suggests that safety recommendations be added over checking guidance on pilots' physical and mental conditions. The pilots operating BK-6724 and BK-6723 were both Indonesian nationals and are undergoing further investigation and action by Batik Air.