What causes turbulence?

EVERYONE expects a few bumps on a flight. But what about the kind of extreme turbulence where, out of nowhere, the plane suddenly plunges from the sky, making you actually think you are going to die?

This kind of turbulence is caused by air pockets, which often appear to come out of nowhere because they are invisible, and therefore difficult to detect.

But although this might be alarming, Markus Wahl of the German pilots association vereinigung Cockpit says it is completely harmless. “The sudden drop may be unpleasant, but for the aircraft it is in no way dangerous,” he says.

Even the term “air pocket” is deceiving, Wahl says. “There are no air pockets, at least not in the sense that there is some kind of hole in the air.”

The effect is actually caused by the friction between different jetstreams, which can sometimes make a plane drop a few metres. “The plane loses altitude, causing a feeling similar to being on a roller coaster,” Wahl says.

While turbulence is not dangerous to planes, it can cause injuries to passengers. For this reason, it’s best to keep your seatbelt fastened at all times.

In most cases, pilots try to steer around turbulence, or to quickly get away from it, by either changing course or flying at higher or lower altitudes.