Severe turbulence struck a Singapore Airlines flight from London Heathrow earlier today, with one man killed and many others “launched into the ceiling”.

Authorities believe a 73-year-old British man, who had a heart condition, likely died from cardiac arrest, with at least 30 others injured as a result of the turbulence.

Deaths from turbulence are extremely rare, and the US’ Federal Aviation Administration (FAA) said 146 passengers and crew have been seriously injured by turbulence between 2009 and 2021.

Read more:
Images show damage in plane after one killed in turbulence

But what could have caused the incident, what types of turbulence exist, and are the events getting worse? Here’s what experts have said so far:

What does the flight data show?

Flight data shows a spike in altitude of around 275ft (84m) at 2.49pm local time. Shortly after, the plane returned to a cruising altitude of around 37,000ft (11,277m).

According to Flightradar24, “the flight encountered a rapid change in vertical rate, consistent with a sudden turbulence event”.

At 3.03pm local time, the flight changed course and began its diversion to Bangkok.

Around 20 minutes later, at about 3.25pm, the flight declared an emergency – a Squawk 7700 – before landing in Bangkok at 3.45pm.

What could have caused the turbulence?

Tim Atkinson, an aviation consultant and pilot, told the Sky News Daily podcast he believes “it’s fairly clear” the Singapore Airlines flight “encountered atmospheric turbulence”.

He noted that the area – called the Intertropical Convergence Zone – where the Boeing 777 plunged 6,000 feet is “renowned among pilots, and I dare say passengers, for turbulence”.

“Despite abundant caution occasionally, there’s turbulence ahead which can’t be identified, and the unfortunate result of an encounter is injury and, very rarely, fatality,” he said.

Mr Atkinson also noted that the larger the aircraft, “the worse the atmospheric perturbation, the disruption in the smoothness of the atmosphere, needs to be to cause major problems”.

He then said the 777 is “one of the largest and, I daresay, most solid airframes widely flying around the world”.

What types of turbulence are there?

Sky News’ weather producer Jo Robinson notes there are a few forms of turbulence – where there’s a sudden change in airflow and wind speed.

Turbulence can often be associated with storm clouds, which are usually well forecast and monitored, allowing planes to fly around them.

Clear-air turbulence (CAT) is much more dangerous as there are no visual signs, such as clouds.

This invisible vertical air movement usually occurs at and above 15,000ft and is mostly linked to the jet stream.

There are clues on where CAT may occur, but generally it can’t be detected ahead of time, which means flight crews can be caught unaware with no time to warn passengers and put seat belt signs on.

It is unclear what type of turbulence the Singapore Airlines flight went through.

How common is an incident like this?

Chris McGee, a commercial pilot for more than 20 years, said in her experience the plane did encounter CAT which is “almost impossible to predict” and comes “out of the blue”.

Ms McGee said turbulence is not in fact that rare, but to experience it to this degree is “phenomenally rare”.

“In my career I’ve experienced one incident of severe turbulence,” she said, adding that she has heard of maybe “two, possibly three incidents of something that extreme” from fellow pilots.

The reported 6,000-ft drop in under five minutes is quite normal in a controlled descent instigated by the pilot, she said.

However, what they experienced was not a nice smooth, controlled descent, but an “absolute maelstrom of the aeroplane flinging itself around all over the sky”.

“It’s awful what happened to those on board, one death is tragic, other people were injured, but something like that is incredibly rare,” she said.

“We do train in the simulator every six months at least where we practicse things we can’t practise in the real aeroplane. Things like emergency procedures, abnormalities and unusual weather conditions like this, for example.

“We are taught how to fly the aeroplane through these extreme events and how to recover them should the plane depart from its normal flight mode.”

Her best advice for any passengers concerned about their safety on the flight is to follow what the cabin crew “strongly suggest and keep their seatbelts loosely tied at all times. On the flight deck that’s what we do. It will protect you”.

Is turbulence getting worse?

It’s been understood for some time that climate change is increasing turbulence during flights, and the trend is set to worsen according to reports.

In June last year, a study from Reading University found that in a typical spot in the North Atlantic – one of the world’s busiest routes – the total annual duration of severe turbulence increased by 55% from 17.7 hours in 1979 to 27.4 hours in 2020.

Moderate turbulence was also found to have increased by 37% from 70.0 to 96.1 hours, and light turbulence increased by 17% from 466.5 to 546.8 hours.

Follow Sky News on WhatsApp

Keep up with all the latest news from the UK and around the world by following Sky News

Tap here

Professor Paul Williams, an atmospheric scientist who co-authored the study, said at the time: “My message from this is we need to do something otherwise flights will become more turbulent in future [as global heating increases further].”

Professor Paul Roundy, from the University of Albany, said on X on Tuesday that the 55% increase in “a very infrequent signal gives a real, but small, change in absolute risk”.

He noted that “it’s not something a randomly selected passenger should worry about,” before adding: “Airline travel of the future won’t be fraught with wings ripped off planes, or have thousands of dead or injured passengers.

“It will mostly look like it does today.”

A passenger travelling on a plane where a man died after the aircraft hit extreme turbulence has said she was “thrown to the roof and the floor”, while another said he “won’t be flying again for a while”.

A 73-year-old British man died from a suspected heart attack and dozens more were injured after “sudden extreme turbulence” on a London-Singapore flight.

Singapore Airlines flight SQ321 left Heathrow Airport on Monday night but was forced to make an emergency landing in at Bangkok, landing at 3.45pm local time.

Passengers have said seatbelts spared people from injury and passengers were “launched into the ceiling” of the jet.

Australian Teandra Tukhunen, who had her left arm in a sling in Bangkok’s Samitivej Srinakarin Hospital, said she was asleep and “was woken up because I was thrown to the roof and then to the floor”.

Ms Tukhunen, 30, said when the seatbelt sign came on “pretty much immediately, straight after that I was flung to the roof, before I had time to put my seatbelt on unfortunately.

“It was just so quick, over in a couple of seconds and then you’re just shocked. Everyone’s pretty freaked out”.

Asked if it was scary, she shrugged: “Life happens. Things happen. The pilots saved our lives, that’s all that matters in the end.”

Passenger Joshua said “I don’t think I’ll be flying again for a while” after the incident which he called “quite scary”.

Lying on a trolley in the same hospital, he described hearing “one huge loud noise, things were coming through the ceiling, water everywhere, people crying… it wasn’t a fun end to the journey”.

He said he was in “a lot of pain” and felt a lot worse after the news of the passenger’s death had “sunk in”.

British passenger Andrew Davies said “anyone who had a seatbelt on isn’t injured”.

Mr Davies said the seatbelt sign came on, but crew members didn’t have time to take their seats.

“Every single cabin crew person I saw was injured in some way or another, maybe with a gash on their head. One had a bad back, and was in obvious pain,” he said.

Passenger Dzafran Azmir described the chaos on board after the plane rose, then fell.

Mr Azmir said: “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 a seatbelt was launched immediately into the ceiling.

“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.”

Kittipong Kittikachorn, head of Bangkok airport, described the disorder he found when he boarded the aircraft after the most critically injured passengers and crew had been evacuated.

Mr Kittikachorn said: “I saw things lying everywhere and many air crew injured.”

He said it’s believed the turbulence hit while people were having breakfast and that an “air pocket” was to blame.

Mr Kittikachorn said most of the passengers he had spoken to had been wearing their seatbelts.

A spokesperson for Samitivej Srinakarin Hospital said: “Seventy-one people needed treatment and six of them had critical injuries”.

Read more:
Images show damage in plane after one killed in turbulence
Is flight turbulence getting worse – and what types are there?

However, Singapore Airlines seemed to contradict those numbers and said only 30 people had been taken to hospital.

Follow Sky News on WhatsApp

Keep up with all the latest news from the UK and around the world by following Sky News

Tap here

Singapore Airlines said the pilot declared a medical emergency and landed in Bangkok after “sudden extreme turbulence over the Irrawaddy Basin at 37,000 feet about 10 hours after departure”.

In a statement, the UK Foreign Office said it was “in contact with the local authorities”.

Forty-seven Britons were among the 211 passengers and 18 crew onboard the plane, a Boeing 777-300ER.

A former Royal Marine accused of spying for Hong Kong’s intelligence service has died in unexplained circumstances in a park in Berkshire.

Matthew Trickett, 37, was charged with offences under the National Security Act earlier this month.

His family said in a statement: “We are mourning the loss of a much-loved son, brother and family member.”

They also appealed for privacy “at this difficult time”.

Thames Valley Police said officers were called to Grenfell Park, Maidenhead, at around 5.15pm on Sunday following a report from a member of the public.

The force said in a statement: “Officers attended the scene and found a man. Emergency treatment was commenced but sadly the man was pronounced dead at the scene.

“An investigation is ongoing into the death, which is currently being treated as unexplained.

The force added that a post-mortem would be conducted in “due course”.

Read more from Sky News:
British man dies in severe turbulence on flight
Mauricio Pochettino leaves Chelsea
Trump decides not to take stand in hush money trial

Trickett was charged alongside Chi (Peter) Leung Wai, 38, from Staines, and Chung Biu Yuen, 63, from Hackney, east London, with assisting a foreign intelligence service, contrary to the National Security Act, and with foreign interference, contrary to the National Security Act.

“The foreign intelligence service to which the charges relate is that of Hong Kong,” the Metropolitan Police said at the time.

At the time, police said that while the alleged offences were “concerning”, there was not believed to be any wider threat to the public.

It was alleged that between 20 December and 2 May, the trio agreed to undertake information gathering, surveillance and acts of deception that were likely to materially assist a foreign intelligence service.

They were also accused of forcing entry to a UK residential address on 1 May.

Trickett and his co-defendants appeared at Westminster Magistrates’ Court on 13 May, where they spoke only to confirm their names.

They were then released on bail and were next due to appear at the Old Bailey in London on Friday.

Prosecutor Kashif Malik said during last week’s hearing that Trickett had attempted to take his own life after being charged and asked for him to be remanded in custody for his own welfare.

Case referred to police watchdog

Thames Valley Police said Trickett’s case had been referred to the police watchdog, the Independent Office for Police Conduct (IOPC), because he had been “on court bail, awaiting court proceedings, which required him to register at a police station regularly”.

The force said a referral was “normal in such circumstances where there has been a death following police contact”.

It added: “The IOPC have assessed that referral and decided that the matter should be investigated by Thames Valley Police’s Professional Standards Department.”

Trickett’s solicitor Julian Hayes, a senior partner at Berris Law, said: “It has sadly been confirmed by Thames Valley Police, that the body found… was that of our client.

“We are naturally shocked at this news and supporting his family as best we can.”

Mr Hayes added: “Following a mandatory referral [to] the Independent Office for Police Conduct, due to the prior contact with police, the matter has now been passed on to Thames Valley Police’s Professional Standards Department.

“It would therefore not be appropriate for us or the family to comment any further at this stage.”

Trickett, who was from Maidenhead, was formerly employed by the UK Border Force at Heathrow Airport, before joining Home Office Immigration Enforcement in February this year.

Anyone feeling emotionally distressed or suicidal can call Samaritans for help on 116 123 or email jo@samaritans.org in the UK. In the US, call the Samaritans branch in your area or 1 (800) 273-TALK