Many of us have heard fellow airline passengers talk about hitting an "air pocket" during a rough flight, especially if the plane dips suddenly and unexpectedly. It may seem like the aircraft suddenly flew into a pre-existing pocket of malicious air just waiting to jostle cups of stale coffee and scare nervous passengers.
If people were riding in a car or bus on pavement, the sudden bump would be attributed to a pothole in the road. Except, of course, there are no potholes in the sky; there are no "pockets of air" for the airplane to fly through.
So what exactly is an air pocket?
Despite the phrase's popularity, there really is no such thing as an air pocket it's merely another term for ordinary turbulence.
Airplane passengers feel turbulence when updrafts and downdrafts buffet the plane's body and wingssometimes both at the same time from different directions. Turbulence is common and most of it is harmless.
Airplanes encounter turbulence because they are moving under their own power against the atmosphere. However, lighter-than-air craft,such as hot air balloons, rarely if ever encounter turbulence because they are going with the wind, not pushing against it.