Clear-air Turbulence - Effects On Aircraft

Effects On Aircraft

In the context of air flight, CAT is sometimes colloquially referred to as "air pockets".

Standard airplane radars cannot detect CAT, as CAT is not associated with clouds that show unpredictable movement of the air. Airlines and pilots should be aware of factors that cause or indicate CAT to reduce the probability of meeting turbulence, as it can injure crew and passengers and even affect flight safety.

Aircraft in level flight rely on a constant air density to retain stability. Where air density is significantly different, for instance because of temperature gradient, especially at the tropopause, CAT can occur.

Where an aircraft changes its position horizontally from within the jet stream to outside the jet stream, or vice versa, a horizontal temperature gradient may be experienced. Because jet streams meander, such a change of position need not be the result of a change of course by the aircraft.

Because the altitude of the tropopause is not constant, an airplane that flies at a constant altitude would traverse it and encounter any associated CAT.