A passenger travelling on the diverted flight has described a “very dramatic drop” which launched everyone without a seatbelt on “immediately into the ceiling” – in some instances denting the overhead lockers.

“Suddenly the aircraft starts tilting up and there was shaking so I started bracing for what was happening, and very suddenly there was a very dramatic drop so everyone seated and not wearing seatbelt was launched immediately into the ceiling,” Dzafran Azmir, a 28-year-old student on board the flight told Reuters.

“Some people hit their heads on the baggage cabins overhead and dented it, they hit the places where lights and masks are and broke straight through it.”

Here is the route which flight SQ321 was travelling when it was diverted to Bangkok.

The US National Weather Service says: “Turbulence is caused by abrupt, irregular movements of air that create sharp, quick updrafts/downdrafts. These updrafts and downdrafts occur in combinations and move aircraft unexpectedly.”

The US Federal Aviation Administration (FAA) defines clear-air turbulence as “sudden severe turbulence occurring in cloudless regions that causes violent buffeting of aircraft … CAT is especially troublesome because it is often encountered unexpectedly and frequently without visual clues to warn pilots of the hazard.”

Here is the airline’s statement in full:

“Singapore Airlines flight SQ321, operating from London (Heathrow) to Singapore on 20 May 2024, encountered severe turbulence en-route. The aircraft diverted to Bangkok and landed at 1545hrs local time.

“We can confirm that there are injuries and one fatality on board the Boeing 777-300ER. There were a total of 211 passengers and 18 crew on board.

“Singapore Airlines offers its deepest condolences to the family of the deceased.

“Our priority is to provide all possible assistance to all passengers and crew on board the aircraft. We are working with the local authorities in Thailand to provide the necessary medical assistance, and sending a team to Bangkok to provide any additional assistance needed.

“We will provide regular updates on our Facebook and X accounts.”

Yes, very rare. But injuries on board an aircraft can be alarming.

Writing for the British Airline Pilots’ Association (Balpa), former pilot and flight safety specialist Steve Landells says: “The injuries we see tend to occur when people aren’t strapped in. This may be because the turbulence is encountered without warning but we also see quite a lot of people hurt because they don’t obey the ‘fasten seat belt’ instructions.”

Cabin crew are particularly vulnerable.

One passenger has reportedly been killed and several others have been injured after a flight from London to Singapore was hit by severe turbulence.

The Singapore Airlines flight was forced to carry out an emergency landing in Thailand, where it made an emergency landing shortly before 4pm local time.

The flight departed from Heathrow airport on Monday evening before hitting bad weather conditions.

My colleagues Holly Evans and Simon Calder have the breaking report, which you can refresh for updates:

Hello, we’ll be using this blog to bring you live updates after a Singapore Airlines flight from London was forced to make an emergency landing in Bangkok due to severe turbulence, with reports of a fatality and multiple injuries on board.