Incidents of airliners hitting turbulence seem to be increasing, say experts

Global climate changes likely to produce more 'choppy air,' not less; 'lap babies' at risk

Recently, airborne turbulence reminded anyone who has ever flown on a plane that it can do much more than spill drinks or mess up handwriting. At its worst, it can be deadly.

United Airlines Flight 1676, a Boeing 737 en route from Denver to Billings, experienced “pandemonium” when it encountered severe turbulence in late February. What one expert called “26 seconds of hell” injured six passengers and two crew members; one flight attendant was hospitalized after striking her head so hard she cracked a ceiling panel. News reports noted that an unsecured baby flew from its mother’s arms, but thankfully, landed safely in another row.

Despite technological advances in detecting and avoiding it, turbulence remains a threat to anything that flies, including civil, military and commercial aircraft of any size  and a range of experts believe global climate changes will be producing more incidents of turbulence.

Just three days after the United incident, eight people were hospitalized after a Cathay Pacific Boeing 747 hit turbulence over Japan. In January, another wide body — a Boeing 777, also operated by United — had to return to Newark Airport after five crew members were injured by turbulence.

According to the Federal Aviation Administration, in-flight turbulence is the leading cause of injuries to airline passengers and flight attendants in nonfatal accidents. Every year as many as 58 people in the U.S. are injured while not wearing seat belts. From 1980 through 2008, U.S. airlines reported 234 turbulence events severe enough to be categorized as accidents, resulting in 298 serious injuries and three fatalities. Another 147 injuries happened between 2009 and 2011. Says the FAA: “At least two of the three fatalities involved passengers who were not wearing their seat belts while the seat belt sign was illuminated.”

Independent aviation safety site offers a primer on turbulence, providing detailed explanations and tips for those who suffer from aerophobia. It also notes that 17 people have died in six airline accidents caused by turbulence worldwide since 1980. The most recent involved a United 747 over the Pacific Ocean in 1997 that seriously injured three crew members and killed one passenger.

Todd Curtis, who founded the site, says he isn’t aware of reliable statistics on the rate or number of turbulence events and suggests that “may be impossible,” since no requirement exists for airlines to report them when no injuries or aircraft damage are sustained. He adds, “There is no acceptable standard or objective definition of what constitutes turbulence. For some, including me, brief turbulence that rattles the plane a bit may get my attention, but it may not cause unbelted passengers to fly out of their seats.”

What is turbulence? Irregular or disturbed airflow in the atmosphere. There are several categories, as well as subcategories. Airline passengers are most likely to encounter the low-level variety, in or near thunderstorms. But additional factors can create unstable conditions, including jet streams, heat, other aircraft and mountains. And pilots, airline dispatchers and air traffic controllers particularly fear clear-air turbulence (CAT), since it is difficult to detect by sight or even via radar.

Experts I talked to say Flight 1676, out of Denver, likely encountered CAT, which may have been fueled by mountain waves — a potent force in the Rockies that dispatchers try to avoid when creating flight plans. "A mountain wave is like a roller coaster, long ups and downs, versus other turbulence, which jars and shakes the plane or makes it feel like going down a gravel road," explains a dispatcher for a major U.S. carrier.

2011 report from the National Oceanic and Atmospheric Administration underscores the dangers: “As winds become stronger aloft, mountain wave turbulence will develop more often and may cause significant damage to the structure of aircraft and result in loss of control.” Flying at higher altitudes isn’t always an easy fix: Two-thirds of turbulence-related accidents occur at or above 30,000 feet, the FAA says.

Global changes in climate are expected to result in bumpier flights, at the least, crossing the Atlantic Ocean. A paper published last year by two British environmental scientists concluded that increased carbon dioxide in the atmosphere increases both the strength and frequency of CAT: “Our results suggest that climate change will lead to bumpier transatlantic flights by the middle of this century. Journey times may lengthen, and fuel consumption and emissions may increase. Aviation is partly responsible for changing the climate, but our findings show for the first time how climate change could affect aviation.” As an FAA-licensed dispatcher who worked in airline flight operations, I also talked to several dispatchers who confirmed that turbulence incidents seem to be on the increase.

That said, it’s important to recognize how well commercial aircraft are built. In its Aviation Safety FAQs, Boeing reports: “You can be assured that the airplane is built to withstand these conditions.” In answer to the question, "Can the wings break off?" the aircraft manufacturer replies: “Actually, they can, given enough force. For every new model Boeing designs, the wings are bent until they break. Breaking a wing requires far more force than anyone has ever come close to experiencing in actual flight. You may see the wings flapping a bit during turbulence. They’re designed to be flexible, in part to ensure they don’t fracture. Airplane wings are very strong.”

The only FAA-licensed aircraft mechanic to serve as a board member of the National Transportation Safety Board believes most aircraft can withstand turbulence. “The damage to airplanes is low,” says John Goglia. “But the damage to people is high.” Even though we have not seen a catastrophic turbulence event in decades, he agrees the total number of incidents seems to be on the rise.

The last commercial airline crash directly attributed to turbulence occurred in 1981, when a Fokker F28 operating for a Dutch commuter carrier encountered weather so severe it was later deemed a tornado; all 17 aboard were killed. But even if the aircraft remains intact, one expert likens the situation to a carton of eggs: Just because the carton stays intact doesn't necessarily mean the eggs won't crack.

The risk of an adult — let alone a small child or baby — being thrown about the cabin is apparent. But another serious risk is posed by projectiles; virtually any unsecured item can cause serious bodily harm when a plane is buffeted by turbulence. Statistics can be hard to come by, but research indicates it’s a serious and growing problem.

A 1998 study by the Flight Safety Foundation found that baggage falling from overhead bins is a ubiquitous hazard: “Among the 14 largest U.S. carriers, there are an estimated 4,500 incidents annually, or an average of one every two hours. Worldwide, it is estimated there are 10,000 injuries a year, or an average of one every hour.” Now consider that was 16 years ago, when cabins weren’t nearly as full, and before checked baggage fees prompted passengers to cram overhead bins with carry-ons.

As hard as it may be to think about, an unsecured baby can become a "projectile" as well. That’s why one retired government attorney believes airlines may be vulnerable to liability lawsuits due to unrestrained babies, despite the FAA’s refusal to mandate infant restraints. If a baby is injured, the attorney told me, or if the baby injures another person, it could be legal grounds to sue because the airlines have not made such dangers clear to many passengers.

The NTSB is launching a full investigation into Flight 1676, and undoubtedly its findings will include a condemnation of the FAA’s refusal to force U.S. airlines to ban lap babies under 2, precisely because of the threat of serious injury and death posed by turbulence and other survivable events. After all, the NTSB has been publicly feuding with the FAA over this issue for decades.

“It is unfortunate to have history repeat itself, such as the incident that played out on United this past week,” says Jennifer Stansberry Miller, an advocate for airline accident survivors and victims’ families. “If this does not raise the awareness of having children under the age of 2 properly restrained in flight, what will? A fatality? Even then, how many children will have to potentially endure such a violent injury or even death for the FAA to mandate this change?”

The good news: The lap child onboard Flight 1676 apparently was not seriously injured. The bad news is, in the absence of greater educational efforts from the FAA and U.S. airlines, the need to warn parents and caregivers about the dangers of flying with lap kids is greater than ever.


• Two words: Buckle up. Experts say you should be strapped in at all times. As the Association of Flight Attendants says, “Passengers should keep seat belts fastened during the entire flight — even if the seat belt sign is off.”

• Don’t leave overhead bin doors open; if you need to retrieve something, close it afterwards.

• If you’re lucky enough to have an empty seat next to you — a statistically challenging proposition in these days of 83 percent passenger load factors — don’t leave large objects such as carry-on bags unsecured.

• If you leave your seat, airline manufacturer Boeing advises: “Hold on to the seat backs or overhead bins when walking in the cabin.”

• Don’t even consider holding your baby in your lap rather than using an FAA-approved safety device. Unless your name is Clark Kent, you aren’t stronger than the G-forces generated by turbulence.

• If you do encounter turbulence, listen to announcements and follow instructions. Later, be careful when opening the bins.

William J. McGee, the lone consumer advocate on the Department of Transportation’s Future of Aviation Advisory Committee, is the author of "Attention All Passengers." He teaches at Vaughn College of Aeronautics and Technology in Queens, N.Y.