Five myths about air turbulence

Five myths about air turbulence

Credit: NOAA, courtesy of USA TODAY

Bad weather can cause dreaded air turbulence. This aircraft is flying in the eye of Hurricane Caroline in 2001.

Print
Email
|

by Everett Potter, special for USA TODAY

khou.com

Posted on July 11, 2014 at 5:11 PM

For many fliers, encountering air turbulence is the most challenging aspect of any flight. The effects of turbulence, which can cause an aircraft to shake and move suddenly and erratically from side to side or up and down, can be distressing and even frightening, sparking fear that the airplane is out of control and about to crash or break apart. So we spoke with two notable pilots to expose the truth behind five of the most common myths of air turbulence.

1. Pilots always get a lot of warning about air turbulence.

There's no mystery about what air turbulence is: It's created by atmospheric pressure, jet streams, and the air that circulates in mountainous areas, as well as weather fronts and thunderstorms. There's also so-called clear air turbulence, which are air masses moving without any obvious visual clues such as clouds, literally coming out of the blue.

"It helps to visualize flight as a river flowing rapidly over rocks, where water is forced upward and then down, with swirls and eddies," says Captain Chesley "Sully" Sullenberger, retired US Airways pilot, speaker, author and CBS news safety & aviation expert. In short, turbulence is a normal part of flying and every pilot knows that they might encounter it in the course of a given flight.

Still, many passengers think that pilots have some device in the airplane to provide warning about approaching turbulence, which can't be detected by radar. But there is no such technology.

"We generally don't get more than a general warning," Sullenberger says. That warning comes from aircraft flying ahead at the same altitude reporting to the nearest air traffic control. Based on a report of turbulence, a pilot can then change altitude or change speed to anticipate and avoid it. Sully says that education, training, experience and judgment to recognize conditions are the most important tools for any pilot to handle turbulent air. Even so, turbulence is often unpredictable, especially if you're flying in remote areas where there are few aircraft reporting to local air traffic control.

2. Severe turbulence can break up an airplane.

The last major air disaster attributed to turbulence was on March 5, 1966, in Japan, near Mount Fuji, when a BOAC 707 was destroyed, along with all 124 passengers and crew. The FAA says that "The aircraft suddenly encountered abnormally severe turbulence ... which imposed a gust load considerably in excess of the design limit."

But as Captain John Cox, a retired airline captain with US Airways, owner of Safety Operating Systems and author of USA TODAY's "Ask the Captain" column points out, that was nearly 50 years ago and today's aircraft "are designed and tested to withstand far more turbulence than most people have ever experienced. If you had a flight where it was a memorable experience of turbulence, we call that 'moderate chop'."

Sullenberger concurs about contemporary aircraft design, noting that "today's aircraft are designed with a large safety margin. The Boeing 787, for example, is built with wings that are designed to flex. You may actually see them move up and down, a movement that is designed to dampen motion."

Pilots may change speed and altitude multiple times in search of a smoother ride. When the ride gets a lot rougher, says Cox, pilots will aim for "turbulence penetration speed, the speed which the manufacturer indicates is the best structural speed for a particular aircraft to handle heavy turbulence."

3. When the seat belt sign is off, it's okay to unfasten your seat belt.

The sage advice is that you should keep your seat belt fastened even if the plane has stopped shuddering and shaking and the ride feels about as eventful as sitting on your living room sofa.

"Keeping your seat belt fastened is cheap insurance," says Sullenberger. "I recommend that it stays fastened during the entire flight."

Because turbulence can arrive without warning, especially clear air turbulence, it can be especially dangerous for anyone who isn't buckled in. Passengers who aren't wearing their seat belts are more likely to be thrown from their seats, injuring themselves as well as other passengers.

"Put it on and keep it fairly taut," Sullenberger says. "A few minutes after I put mine on, I don't even feel it."

4. There's nothing I can do about turbulence.

It turns out that you can do several things to guard against the effects of turbulence. While wearing your seat belt during the entire flight is the most important, you can also choose flights that are likely to encounter less turbulence. For example, in the summer, the sun heats the earth's surface unevenly, often producing turbulent air. If you choose to fly early in the day in summer, you're more likely to have a smoother flight. Sullenberger suggests that fliers who are especially bothered by turbulence choose a seat over the wings of the aircraft, which puts them close to the center of mass and reduces the effects of turbulence.

He also has a favorite exercise to reduce fear of turbulence before you fly.

"The next time you're riding as a passenger in a car, close your eyes and mentally catalog the frequency and intensity of every noise you hear and vibration you feel," he says. "When you do that and become sensitized to what we've all become desensitized to, you realize that most car trips are much bumpier than your average plane ride."

5. People get injured by turbulence all the time.

Every year, the FAA keeps a record of injuries due to turbulence and the numbers are reassuringly low. In 2013, 24 people were injured, 13 of them crew. In 2012, 32 people, 21 of them crew. In fact, in the past 10 years, an average of 34 people a year have been injured in incidents of turbulence, on average 20 of them crew members. That's out of approximately 800 million plus passengers in the air each year.

Those most at risk? Flight attendants working the flight, lap children and passengers who don't have their seat belts fastened.

Print
Email
|