In October 2023, a Turkish Airlines flight experienced a significant loss of cabin pressure and had to initiate an emergency descent.
The incident occurred during a routine flight from Bangkok to Istanbul, but the aircraft landed safely back in Bangkok.
The Aircraft Accident Investigation Committee of Thailand recently opened an investigation into the incident, categorizing it as a "serious incident" requiring emergency oxygen use by the flight crew.
In October last year, a Turkish Airlines Airbus A330 operated a routine flight from Bangkok to Istanbul and was climbing out of the runway when the flight crew initiated an emergency descent due to pressurization issues.
Although the incident happened some time ago, with the aircraft having returned safely to Bangkok, the Aircraft Accident Investigation Committee of Thailand recently opened an investigation into the matter, according to The Aviation Herald.

Losing cabin pressure
This incident happened on October 9th, 2023, and the Airbus widebody involved was registered TC-JOJ, a less than 10-year-old Airbus A330-300 previously delivered to Turkish Airlines in June 2015. Operating as flight TK 59 - a daily scheduled flight service between Bangkok's Suvarnabhumi Airport and Istanbul Airport, the aircraft took off at approximately 08:21 that day, just slightly behind schedule, but otherwise, everything was routinely normal.

While climbing through to flight level 27,000 feet out of Suvarnabhumi Airport's runway 19R at approximately 08:42, the flight crew of TK 59 squawked 7700 and initiated an emergency descent to flight level 10,000 feet, citing a significant loss of cabin pressure. According to data from Flightradar24, the widebody descended from about 27,775 feet to 10,000 feet in a quick matter of less than 10 minutes. The aircraft maintained that altitude and only dropped to 9,975 feet momentarily at approximately 08:57 when entering a small holding pattern.