Why Flights Are Being Affected by Extreme Turbulence

On May 21, a Singapore Airlines Boeing 777 flying from London to Singapore ran into turbulence so severe that it hurled passengers and items around the cabin. The incident made headlines around the world, sparking concerns over airline safety and whether turbulence could become a growing threat to aviation.

Flight SQ321, which carried 211 passengers and 18 crew members, made an emergency landing in Bangkok, where passengers were taken to the hospital, some with life-changing injuries. A 73-year-old British man died of a suspected heart attack before the flight landed.

A preliminary report released on May 29 found that in less than a second, the aircraft dropped 178 feet—almost the height of Italy’s Leaning Tower of Pisa—which “likely resulted in the occupants who were not belted up to become airborne.”

Extreme turbulence events are rare, especially ones that result in death or serious injury to passengers. However, less than two weeks after the deadly Singapore Airlines incident, a flight en route to Dublin from Doha, Qatar, experienced extreme turbulence that injured six passengers and six crew members. In a statement, Qatar Airways described the injuries passengers and crew sustained as minor.

In March, a LATAM Airlines flight bound for Auckland, New Zealand, from Sydney likewise experienced severe turbulence, with 50 passengers receiving medical assessment and 12 persons taken to the hospital upon landing—one with a serious injury.

The number of serious incidents in such a short span of time has raised questions about turbulence—which is commonplace on commercial flights—and why severe instances are being reported more frequently.

Why Do Flights Experience Extreme Turbulence?

Turbulence is common on flights, and there is usually little to worry about. The irregular motion happens when an airplane hits a strong wind current that can push or pull the plane. While most commercial planes fly high enough to avoid these wind patterns, it doesn’t make them immune to such events.

“An aircraft gets lift by having air pass over the top and bottom of the wing. Typically, that air flows smoothly like it would coming out of a house fan on your face,” said David Cohen, the dean of Lynn University’s College of Aeronautics.

He told Newsweek that when a “momentary disruption to that airflow over the wing” occurs, “then there is a momentary disruption to the lift, which we sense as turbulence. In the house-fan analogy, passing your hand in front of the fan would cause a momentary disruption of the air on your face; but in terms of the overall cooling of your face, you likely wouldn’t notice. The same is true for momentary disruptions of airflow over a wing. Given the size, speed, and weight of modern airliners, these small perturbations of airflow are rarely felt as any significant change of lift.”

So why did such extreme turbulence happen on flight SQ321? While many may associate turbulence with observably poor weather, such as storms, it can happen at any time, even when the weather on the flight route appears to be favorable.

Clear-air turbulence is much more dangerous, as there are no detectable signs. CAT does not show up on detection devices, and the only warnings come from aircraft signaling that they have already experienced it. While the preliminary report from Singapore’s Transport Safety Investigation Bureau does not specifically mention CAT as the cause of May’s deadly incident, analysts have cited it as the most likely cause, given that the aircraft’s pilots were unable to avert the disaster.

“The turbulence was likely undetectable, but there will be more investigation into how the flight planning was done, and if it was done correctly. Or if there was anything that could have been anticipated,” said Timothy Loranger, a lawyer in Los Angeles with a pilot’s license and Marine Corps veteran with years of experience working on fighter jets and tankers as an aircraft mechanic.

Is Turbulence Getting Worse?

Some scientists think so. “We now have strong evidence that turbulence is increasing because of climate change,” Paul Williams, a professor of atmospheric science at the University of Reading in the U.K., told Mashable in May. “We recently discovered that severe clear-air turbulence in the North Atlantic has increased by 55 percent since 1979.”

Unfortunately, the issue is likely to get considerably worse. “Our latest future projections indicate a doubling or trebling of severe turbulence in the jet streams in the coming decades, if the climate continues to change as we expect,” Williams added.

Despite the threats posed by climate change, not only for the aviation industry and its customers, Cohen mentioned burgeoning developments looking to counter instances of CAT. He cited the work of the Austrian firm Turbulence Solutions, which he said is developing “a technology to not only identify turbulent air but also to cause the aircraft to anticipate and counter the turbulence.”

“It’s a bit akin to noise-canceling headphones—the headphones detect ambient sound and then produce an opposite sound that cancels out the ambient one. In Turbulence Solutions’ concept, the system senses the air movement, and before the turbulence has a chance to move the aircraft, the system activates the various flight controls to counter the turbulence,” he continued.

“It’s a new technology that is still in testing and development but has the potential to improve aviation safety across various types of aircraft and applications,” Cohen added.

Can Extreme Turbulence Be Avoided?

While there are mitigations in place to avoid running into severe turbulence, in some instances the problem cannot be avoided.

“In the case of most CAT events, there may have been nothing to indicate to the pilots that the air was anything but smooth,” Cohen said. Sometimes, turbulence so severe cannot be countered by the aircraft itself once encountered, he added.

“Despite efficient wing design and powerful engines, an aircraft may not have enough performance to counter certain turbulence situations. Modern airliners can climb at between 2,000 and 5,000 feet per minute depending upon their weight, air temperature, air pressure, and altitude,” Cohen continued. “Some turbulent air movements, many times associated with thunderstorms, can produce columns of air moving downward at over 6,000 feet per minute. In this scenario, the aircraft cannot overcome the force of the air moving it downward.”

Experts have stressed the importance of following safety advice while onboard an aircraft. “When passengers don’t have their seat belts on and may be moving about the cabin, a sudden loss of altitude can cause them to literally hit the ceiling or luggage compartments and suffer serious injuries—concussions, broken bones or even death,” Loranger said.

“Airlines have staff devoted to checking the weather and avoiding what they can, but in severe situations, their immediate response is to get to the ground, in order to protect passenger safety,” he continued. Referring to the Singapore Airlines incident, he said that given the dangerous circumstances faced by the pilots, the fact “that they got the aircraft safely to the ground speaks to their experience and abilities.”

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