All turbulence is the result of different masses of air moving at different velocities colliding into each other. Consequently, all turbulence is mechanical in nature—similar to the eddies around rocks and irregularities along a mountain stream.

There are four dominant types of turbulence: jetstream, clear air turbulence, wake turbulence, and windshear.

Don't let turbulence ground you!  Change your perception of turbulence through knowledge.  Turbulence is an annoying part of flying, not one that should prevent you from flying.   Wouldn't you feel better about flying if you had a pilot tell you the "Plane Truth"? Then download your copy of Capt. Ron's Cleared for Takeoff class packed with 2.5 hours of knowledge and tips to help you become a better flyer.   

Jetstream

The jetstream is a "river" of air that flows at high altitudes above the earth. In the northern hemisphere, it has a west-to-east general movement. The main significance of the jetstream is that it produces our weather patterns.

Clear Air Turbulence (CAT)

Clear air turbulence (or CAT as it is called), is the result of the air that is disrupted around the jet stream. Picture a garden hose swirling around in the upper atmosphere (picture above on the right). That is exactly what the jet stream looks like. At the inner most part of the jet stream called the core, the velocity may be as high as 250 mph. As you move away from the core, the velocity drops off so that at the edge it may be only 50 mph. At each point at which two differing velocities rub against each other, eddies form causing the airflow to be disrupted from its nature to want to be smooth. Now imagine we are flying through this area in our airplane. The variability in the disruption will cause variations in the lift produced by the wings causing the airplane to bounce.

The most problematic of this type of phenomenon is when the airplane hits one of the so-called "air pockets" causing it to suddenly drop. Although it may seem to you that the aircraft is dropping hundreds or even thousands of feet, in reality the airplane likely never descended more than 10 or 20 feet. The reason it seems so dramatic is that it was thrust down in a very short span of time.

The most disconcerting thought reported by many fearful flyers is that perhaps the wings will fall off. They observe the wings "flexing" under the load. Keep in mind that the flexibility of the wings gives the airplane its resilience. If the wings were rigid, they might be inclined to snap like a piece of glass.  Airplanes are designed to withstand all the forces that Mother Nature can dish out.  Keep your seat belt securely fastened, and you will be absolutely safe. 

Wake turbulence

Wake turbulence is created by the airplane itself similar to what happens when you're boating. Some of the airflow over the wing slides down the wing and spirals off each wingtip creating a mini horizontal tornado. This tornado is small and does not last long, but it can play havoc with an unsuspecting aircraft flying through it before it has dissipated.

Sometimes wake turbulence can be visible. If you're lucky enough to fly when the temperature and dew point are very close together—conditions that sometimes exist just before or after a rain shower or when fog is imminent—you can see large clouds forming over the wings just after takeoff or on landing. From the outside you will notice the clouds "sliding" off over the wingtips and trailing off behind like the trail of a sky-writer. The path that these vapor trails follows is the very location in which the wake turbulence exists.

Windshear

Although all turbulence creates windshear—the shearing of two differing velocities of airflow—the term is often used in conjunction with turbulent air that is associated with thunderstorms and near the ground.

As a thunderstorm matures, the heavier, colder air starts to descend. As it displaces warmer air rising, the intensity increases until the air becomes so cold that it "falls" out of the bottom of the thunderstorm. That downward rush of air is called windshear.

As it hits the ground, it starts to bend outwardly like water splashing on a sidewalk producing dramatic surface winds in all directions. For an airplane flying into this area of windshear, it can mean a sudden and dramatic increase in airspeed. In the past, we pilots would reduce the thrust on the engines to allow the airspeed to slow. Unfortunately we learned through tragic accidents that when flying out the other side of the windshear, the opposite condition would be encountered--the airspeed would suddenly decrease. While this would not be inherently bad during cruise at higher altitudes and airspeeds, if it occurs close to the ground during the landing phase, it can leave the airplane without sufficient airspeed to fly with the extra margin we prefer. Because we are close to the ground we cannot descend more rapidly to convert altitude into extra airspeed. And because it takes as much as 15 to 30 seconds for the engines to reach maximum thrust, that strategy is also not likely to benefit us.

What you need to know as a fearful flyer are the things that we do differently now as a result of what we learned from others' mistakes, which are, unfortunately, sometimes fatal.

• We now practice "escape" maneuvers to fly out of such conditions in the highly unlikely event that we encounter them.
• Doppler radar has been installed at the major airports to detect the kind of conditions that produce windshear and associated hazards. When windshear is reported, we simply wait until those conditions pass or go to an alternate airport.
• Finally, all airlines have on-board windshear detection instrumentation, which tells us if we inadvertently were to encounter windshear. In addition to detection, our instruments immediately switch to a mode that directs us to fly with maximum performance to accomplish the escape maneuvers mentioned above.

Turbulence Happens

No pilot ever wants to give passengers a thrill ride through turbulence.   You can easily see evidence of this if you ever fly an airline that offers the radio chanel which lets passengers listen to the conversations between air traffic control and pilots.  They really do talk to each other up there!  In fact, air traffic control is a big reason that flying is so incredibly safe.  And the number one topic of pilots in flight and the controllers is "the ride." If you're able to listen on one of your flights, you'll likely hear them talk about "light chop."  You'll also hear pilots and controllers talk about changing cruising altitude to obtain a smoother ride.    

Turbulence is often an unavoidable part of flying, but remember, as long as you are buckled into your seatbelt, you will be safe!  But if you need a little extra help coping with turbulence, check out the complete outline of the Fearless FlightKit™  with the distracting yet soothing power of the Flight Harmonizer CD™  included in every FlightKit.  It's helped thousands of people fly more comfortably, right through turbulence. 

Knowledge is power when it comes handling turbulence.  Wouldn't you feel better about flying if you knew the "Plane Truth" about flying? Then download your copy of Capt. Ron's Cleared for Takeoff class packed with 2.5 hours of knowledge and tips to help you become a better flyer.  Don't let turbulence ground you!