What happened
Departing from Surabaya-Juanda Airport at 05:35 local time, the aircraft initially climbed to its assigned altitude of FL320, reaching this level approximately 19 minutes after takeoff. During the flight, the crew requested permission from Air Traffic Control to increase their altitude to FL380 and change their heading to 3ical 310 degrees to avoid adverse weather. Shortly after this request, at 06:17, communication with the crew was lost. One minute later, the transponder signal ceased, and the aircraft vanished from radar tracking. At the moment of disappearance, the aircraft was traveling at 353 knots at an altitude of 36,300 feet.
The aircraft is believed to have crashed roughly 80 nautical miles southeast of Pulau Belitung Island, located approximately 200 km from the Singapore Control Area. The region was experiencing marginal weather conditions characterized by storm activity, rain, and turbulence. The flight carried 156 Indonesian citizens, along with three South Korean, one Malaysian, one Singaporean, and one French national serving as the copilot.
Search efforts by the Indonesian Navy located the first pieces of debris approximately 48 hours after the disappearance, about 150 NM east-south-east of Pulau Belitung Island. As of December 30, approximately 40 fatalities had been recovered. The aircraft's tail section was retrieved on January 10, 2015, and the flight recorders were located the following day. The DFDR and CVR were recovered from the water on January 12 and 13, respectively, and transported to Jakarta for investigation.
Findings
At the time of the incident, the aircraft was operating in severe weather conditions involving heavy rain, turbulence, and active storm cells.