What's the name of the circle disk like white cloud that appears at the end of a jet/plane?

Question

Does anyone know what's it called and if theres a good picture of it?

Answer 1

Its known as the Praendtl-Glauert singularity, it happens at the points where a sudden drop in air pressure occurs. It is not necessarily a supersonic phenomenon as evident in the second image.

The images are below

Answer 2

Its called a contrail.

Answer 3

it's a vapor cone.

The Prandtl-Glauert singularity (sometimes referred to as a "vapor cone"), is the point at which a sudden drop in air pressure occurs, and is generally accepted as the cause of the visible condensation cloud that often surrounds an aircraft travelling at transonic speeds, though there remains some debate. It is an example of a mathematical singularity in aerodynamics.

http://apod.nasa.gov/apod/image/0102/son...

Answer 4

I believe you may be referring to a "condensation cloud"

Answer 5

It isn't vapor.  Water vapor is not visible.

Answer 6

I think its called a vortex.

Answer 7

CONTRAIL