How dangerous is turbulence on planes? Here’s what you need to know: NPR

A Lufthansa Airbus A330 D-AIKQ takes off on November 14, 2022. In the past week, seven people were sent to hospital with turbulence-related injuries on a Lufthansa flight.

Christian Kaspar-Bartke/Getty Images

hide caption

change caption

Christian Kaspar-Bartke/Getty Images

A Lufthansa Airbus A330 D-AIKQ takes off on November 14, 2022. In the past week, seven people were sent to hospital with turbulence-related injuries on a Lufthansa flight.

Christian Kaspar-Bartke/Getty Images

Over the past week, significant turbulence has caused one death and one hospitalization on a business flight and seven hospitalizations on a commercial flight. Turbulence usually causes only a bumpy ride, but it varies widely in severity and can cause damage to the aircraft and injuries to the passengers and crew on board – not to mention serious fear and anxiety among flyers.

Here’s what you need to know about how to stay safe and why turbulence occurs.

How often does turbulence cause serious injuries?

Injuries from turbulence are admittedly rare. At airplane cruise levels, only about 3% of the atmosphere has light turbulence, about 1% has moderate turbulence and a few tenths of a percent has severe turbulence at any given time, said Paul Williams, a professor of atmospheric science at the University of Leser who researches turbulence.

“You’re practically guaranteed to be safe,” says Williams.

From 2009 to 2021, there were 30 passengers and 116 crew members seriously injured due to turbulence among the millions of people who fly each year, according to data from the Federal Aviation Administration.

The FAA defines serious injuries as those that require hospitalization for more than 48 hours, or that result in broken bones, severe muscle or tendon damage, damage to internal organs, or second- or third-degree burns. Airlines are not required to report multiple minor injuries, meaning the total number of injuries is underreported.

The majority of passengers seriously injured by turbulence were not wearing seat belts, often because they were using the restroom or walking up or down the aisle, according to a 2021 National Transportation Safety Board report. Injuries can come from luggage falling out of bins and hitting people in the head, people tripping or being thrown into seats or the sides of the cabin or food carts crashing into people.

The NTSB report found that the same was true for crew members, who were most often injured while preparing the cabin for landing or performing cabin service — such as serving food or drink or collecting trash.

The NTSB has not said whether the passenger who died on a business jet from New Hampshire to Virginia on Friday was wearing a seat belt. The agency is still investigating what happened, but told the AP that turbulence-related deaths remain extremely rare.

What is turbulence, exactly?

Turbulence is irregular air movement that causes irregular changes in the altitude or angle of the aircraft, which feels like roughness, pitching or pitching to the people on board.

Atmospheric pressure, air around mountains and weather fronts or storms can all cause turbulence, according to the FAA. Jet streams – narrow bands of strong winds in the upper levels of the atmosphere – are also a common cause of turbulence.

One of the most dangerous types of turbulence is what is known as clear air turbulence, which gives no visible warning and often occurs when pilots do not have their seat belt sign on.

“It’s completely invisible to the naked eye, to radar, to satellites,” says Williams, the weather scientist. “The only information we have about it, really, is when a plane goes through it.”

Climate change is causing more instability in the jet streams and making wind speeds faster, which will add more turbulence when the sky looks clear. By 2050, pilots worldwide can expect to encounter at least twice as much severe turbulence in clear air, Williams found in his research.

Clear air turbulence is what caused a Lufthansa flight traveling from Texas to Germany to unexpectedly fall 1,000 feet last week. The sudden turbulence occurred during the meal service, as crew and passengers moved around the cabin. The plane was diverted to Washington Dulles International Airport, and seven people were taken to the hospital with minor injuries.

Regardless of the turbulence a flight may experience, experts say the best thing passengers can do to avoid injury is to keep their seat belts fastened, follow carry-on baggage restrictions and listen to instructions from pilots and flight attendants.

Turbulence can also mean damage to aircraft

In all, about 65,000 flights encounter moderate turbulence each year, and about 5,500 encounter severe turbulence, according to the National Center for Atmospheric Research.

It’s almost unheard of for turbulence to cause a crash, but it can lead to costly repairs for carriers. Usually the damage is to cabin components such as seats and overhead bins when luggage falls out or people hit them. Turbulence-related injuries, delays and damages cost airlines up to $500 million per year.