Five days after severe turbulence on a Singapore Airlines flight injured 71 and left a British man dead from a suspected heart attack, a Qatar Airways plane flying from Doha to Dublin hit turbulence, injuring twelve, eight of whom were hospitalized.
Qatar Airways passenger Paul Mocc told Irish broadcaster RTE that he saw “people hitting the roof” and food and drink flying everywhere.
The exact cause of the 73-year-old man’s death is under investigation. Authorities said he may have suffered a heart attack, though that hasn’t been confirmed. Based on witness accounts on the Singapore Airlines flight, the number of injuries and the airliner’s sharp descent, experts point to the significant safety hazards that inflight turbulence poses to airline passengers and crews.
Turbulence-related fatalities are quite rare, but injuries have piled up over the years. Some meteorologists and aviation analysts note that reports of turbulence encounters also have been increasing and point to the potential impacts that climate change may have on flying conditions.
Most incidents of planes hitting bumpy air are minor, however, and airlines have made steady improvements to reduce accident rates from turbulence over time. Experts advise air travellers to stay vigilant, stressing the importance of wearing a seatbelt whenever possible as a first line of protection.
Here’s what you need to know.
What is turbulence?
Turbulence is essentially unstable air that moves in a nonpredictable fashion. Most people associate it with heavy storms. But the most dangerous type is clear-air turbulence, which often occurs with no visible warning in the sky ahead.
Clear-air turbulence happens most often in or near the high-altitude rivers of air called jet streams. The culprit is wind shear, which is when two huge air masses close to each other move at different speeds. If the difference in speed is big enough, the atmosphere can’t handle the strain, and it breaks into turbulent patterns like eddies in water.
“When you get strong wind shear near the jet stream, it can cause the air to overflow. And that creates these chaotic motions in the air,” Thomas Guinn, chair of applied aviation sciences department at Embry-Riddle Aeronautical University in Daytona Beach, Florida, explained.
How common are turbulence-related injuries?
Tracking the total number of turbulence-related injuries around the world is difficult. But some individual countries publish national data.
Global Affairs Canada says that although they are rare, incidents involving air turbulence are the leading cause of injuries to both passengers and crew members.
In the U.S., 163 people were injured seriously enough during turbulence events between 2009 and 2022 to require hospital treatment for at least two days, according to National Transportation Safety Board figures. Most of them were flight attendants, who are particularly at risk since they are more likely to be out of their seats during a flight.
Investigations are under way into what happened during the Singapore Airlines and Qatar Airways flights. Singapore Airlines said the Boeing 777-300ER descended 6,000 feet (around 1,800 metres) in about three minutes after hitting severe turbulence over the Indian Ocean.
“It’s not uncommon to have turbulence encounters that cause minor injuries up to, say, a broken bone,” said Larry Cornman, a project scientist at the National Science Foundation’s National Center for Atmospheric Research who has long studied turbulence. “But fatalities are very, very rare – especially for large transport aircraft.”
According to Stuart Fox, director of flight and technical operations at the International Air Transport Association, the last clear air turbulence-related death reported from a major carrier took place in 1997.
Now-standardized safety procedures have significantly helped prevent more cases of serious injuries over the years, Fox noted. They include reviewing weather forecasts, having pilots report when they encounter turbulence and suspending cabin service when planes hit rough air.
Can pilots avoid turbulence?
Pilots use a variety of methods to avoid turbulence, including using a weather radar display. Sometimes they can simply see and fly around thunderstorms.
But clear-air turbulence “is altogether another animal,” according to Doug Moss, a former airline pilot and safety consultant. It can be devastating, he said, “because the time before the incident can be very calm, and people are caught off-guard.”
Air traffic controllers will warn pilots after another plane runs into clear-air turbulence, Moss said. Many pilots also look at the upper-level jet streams along their route for signs of wind shear, then plan to fly above, below or around those areas, he said.
Modern planes are strong enough to handle just about any turbulence. Cabin areas such as overhead bins may receive cosmetic damage, “but these don’t impact the structural integrity of the planes,” Moss said.
Why is turbulence getting worse? Is climate change a factor?
Some scientists note that reports of turbulence encounters are on the rise. There are a number of possible explanations for that, but several researchers have pointed to potential climate impacts.
Guinn, of Embry-Riddle Aeronautical University, explains that some predict climate change could alter the jet stream and up the wind shear, which would consequently drive up turbulence in the air.
In a statement Tuesday, Paul Williams, a professor of atmospheric science at the University of Reading in England, said there was “strong evidence that turbulence is increasing because of climate change.”
Williams said his research team recently discovered that severe clear-air turbulence in the North Atlantic has increased by 55 per cent since 1979. The team’s latest projections signal that severe turbulence in the jet streams could double or triple in the coming decades if global conditions continue as expected, he said.
Still, others say other factors could also be at play. Cornman notes that there could be a rise in overall air traffic – which may increase turbulence encounters as the number of flight tracks, including those in areas of more turbulence, goes up.
What are the most turbulent flight routes?
Turbli ranks flight turbulence analyzing 150,000 routes, giving each flight an eddy dissipation rate to describe the severity. The turbulence levels are light with an edr rate of 0-20, moderate with an edr rate of 20-40, severe with an edr rate of 40-80 and extreme with an edr rate of 80-100.
How can travellers stay safe during turbulence?
In short, wear your seatbelt. Turbulence can be tricky to predict, but experts stress that the first line of defence in the air is keeping the seatbelt fastened, whenever possible.
“Planes are generally built to withstand turbulence,” Guinn said, noting that passengers not wearing their seat belts is a large source of injuries from inflight turbulence. While no precaution is foolproof, wearing a seatbelt greatly increases an individual’s chances of avoiding serious injuries, he said.
“Wear your seatbelt,” Guinn said. he stressed. “That’s just a really quick fix to prevent injury.”
– With files from the Associated Press