Both pilots of a commercial airplane fell asleep midflight, causing the craft to veer off course

Both pilots of an Indonesian commercial airliner fell asleep during a flight in January, causing the plane to veer off course. The pilots flew for nearly half an hour with no supervision.

The Indonesian National Transportation Safety Committee report released Friday outlines how the Batik Air pilots were asleep for about 28 minutes just before descending into Jakarta on Jan. 25.

The pilots were making a return trip from Sulawesi to Jakarta, a two-and-a-half-hour flight with 153 passengers. One pilot received permission to rest from the other when the second dozed off, leaving air traffic control and nearby pilots attempting to reach the plane.

“Several attempts to contact BTK6723 had been made by the Jakarta ACC including asking other pilots to call the BTK6723,” the report said. “None of the calls were responded to by the BTK6723 pilots.”

The report says that the pilot in command slept for about an hour before asking if his second wanted to switch and rest as well, which he declined. The pilot in command then returned to sleep before the second “inadvertently fell asleep,” according to the report.

The second pilot had month-old twin children and was already severely short on sleep, according to the report.

The pilot in command woke up to find the second asleep, and he quickly woke him and returned the plane to its intended route. The plane then landed in Jakarta without incident.

Sleeping in the cabin isn’t uncommon among commercial pilots, who have standard safety procedures to ensure that one attentive, rested pilot is always in command.

Batik Air said the two pilots had been “temporarily suspended,” Agence France-Presse (AFP) reported.

The country’s Transportation Ministry “strongly reprimands” the airline for the incident.

“We will carry out an investigation and review of the night flight operation in Indonesia related with Fatigue Risk Management for Batik Air and all flight operators,” Maria Kristi Endah Murni, Indonesia’s civil aviation director, said, according to AFP.