A Singapore Airlines Boeing 777-300, registration 9V-SWM performing flight SQ-321 from London Heathrow,EN (UK) to Singapore (Singapore) with 211 passengers and 18 crew, was enroute at FL370 about 210nm westnorthwest of Bangkok (Thailand) when the aircraft suffered severe turbulence causing injuries to a number of passengers. The crew descended the aircraft to FL310 and decided to divert to Bangkok where the aircraft landed on runway 19R about 30 minutes later. One passenger was pronounced dead upon arrival, 30 passengers and 7 crew were taken to hospitals.
The airline confirmed there had been severe turbulence causing one fatality and injuries on board of flight SQ-321. The airline later reported: "As of 1950hrs Singapore time on 21 May 2024, 18 individuals have been hospitalised. Another 12 are being treated in hospitals."
There are first reports surfacing in Thai media that a second person may have succumbed to the injuries in hospital.
Authorities in Bangkok reported a British citizen (73) on board died as result of a heart attack. Seven people are in critical conditions. 23 other passengers and 7 crew received injuries of varying degree.
According to ADS-B data the speed over ground of the aircraft dropped rapidly by about 20 knots suggesting changing high altitude winds with no altitude deviation visible prior to starting the (controlled) descent from FL370 to FL310.