Ask the pilot

There's no doubt that turbulence rattles the nerves of uneasy fliers, but is it dangerous?

By Patrick Smith

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Nov. 3, 2006 | "As we cruised toward Portland, a thousand or so feet above the cottony peaks, the slamming came on with a vengeance. We requested a climb, but not soon enough. When the worst of the pummeling hit, it was like being stuck in an upside-down avalanche. Even with a shoulder harness pulled snug, I remember holding up one hand to brace myself, afraid my head might hit the ceiling."

Turbulence: spiller of coffee, jostler of luggage, filler of barf bags, rattler of nerves. But is it a crasher of planes?

Judging by the reactions of many airline passengers, one would assume so. I'd been a commercial pilot for the better part of 10 years, a job that requires its share of impromptu coaching sessions with white-knucklers, and figured I had a pretty good grasp of the fearful flier mind-set. I didn't. Not until I began writing for this magazine, and fielding questions from the public, did I realize how upsetting, if you'll grant the pun, turbulence is for tens of thousands of travelers.

"Turbulence is the issue," says Tom Bunn, a retired captain and licensed therapist. Bunn founded the nation's most popular fearful flier program, SOAR. "It is far and away the No. 1 concern among my clients."

Intuitively this makes sense. Everybody who steps on a plane is on some level uneasy, and there's not a more poignant reminder of flying's innate precariousness, and all its potential complications, than a good walloping at 37,000 feet. It's easy to picture the airplane as a helpless dinghy caught unawares in a stormy sea. Boats are occasionally swamped, capsized or dashed into reefs by swells, are they not? Everything about it seems dangerous.

Except that, in all but the rarest circumstances, it's not. And frankly that boat-airplane analogy isn't a very good one: Airplanes are much less susceptible to deadly upset than boats, and turbulence itself is quite different from a roiling sea. For all intents and purposes, a plane cannot be flipped upside-down, thrown into a tailspin or otherwise flung from the sky by even the mightiest gust or air pocket. Inherent in the design of airliners is a trait known to pilots as "positive stability." Should the aircraft be shoved from its position in space, its nature is to return there, on its own and with no drastic input from the crew. Conditions might be annoying and uncomfortable, but the plane is not going to crash. Turbulence is an aggravating nuisance for everybody on the plane, including the crew. But it's also, for lack of a better term, normal -- as naturally occurring as clouds, precipitation or a summer-day breeze.

When a flight changes altitude in search of smoother conditions, this is by and large a comfort issue. The captain isn't worried about the wings falling off, he's trying to keep his customers as content and relaxed as possible. After landing, pilots are sometimes approached by passengers who remark about the roughness of a flight. "Man, you must have had your hands full with that one!" Yet the crew will have little or no recollection of it having been bumpy at all. Not because they're jaded or cocky (much as that might also be the case), but because they understand the realities of atmospheric instability, and don't misinterpret those rocks, knocks and jigs. Fliers tend to overestimate the effects of turbulence by orders of magnitude. "We dropped like 500 feet in two seconds!" If I've heard that once, I've heard it a thousand times. In truth, a jetliner's altitude is rarely displaced by more than about 50 feet; its bank (turn) and pitch (nose up/down) will seldom change more than a few degrees.

"The motion created by turbulence is insignificant," adds Bunn. "In the cockpit we see the altimeter jiggle ever so slightly, but the anxious flier perceives a free fall. These sensations can be so intrusive that strategies to rationalize them, or escape them entirely, usually fail, even when aided by drugs and alcohol."

During a wind-whipped approach, the frightened passenger is liable to imagine the pilots in a sweaty lather: the captain barking orders as the ship lists from one side to another, hands tight on the wheel. Nothing could be further from the truth. The crew is not wrestling with the beast so much as merely riding things out. Most of the time, pilots will sit back and allow the plane to buck and buffet rather than attempt to recover every lost foot or degree of heading. Indeed many autopilot systems have a special "turbulence" mode. Rather than increase the number of corrective inputs, it does the opposite, desensitizing the system.

Much worse than turbulence itself could be an overzealous reaction to it -- as demonstrated with catastrophic results five years ago, after an American Airlines A300 was hit by the wake from a 747 ahead. The first officer responded with a needlessly violent deflection of the rudder, causing the plane's tail to fracture. The ensuing crash killed 265 people -- the second worst aviation disaster ever on U.S. soil.

Design flaws and a possibly preexisting stress crack may have played a role in the A300 crash, and wake turbulence, to be discussed in greater detail next week, is an altogether different phenomenon than the naturally occurring kind. It's unfair to say that turbulence, in and of itself, brought down Flight 587. Just how rare is such an occasion? Around the globe each day, about 5 million people take to the air aboard 35,000 commercial departures. Yet over the past half-century, the number of airliners downed by turbulence can literally be counted on one hand, and almost always there were extenuating circumstances.

Not that you'd know it listening to the media. Last summer, after a Sibir Airlines Airbus A310 overran a runway at Irkutsk, Russia, killing 124, news stories, including a widely disseminated item from the Associated Press, spoke of "turbulence" as a "potential cause." That one had me sputtering and dashing off another petulant e-mail to the AP. It's possible that blustery weather, together with crew error, led to an unstable approach and the subsequent overrun, but the implication was that rough air itself had somehow slammed the Airbus to the ground or swept it from the runway.

Next page: The right brain is screaming, "Can't you see there is nothing underneath us!"