It's called Contrails (condensation trails), and it's humidity condensing (gases that turn to fluids) as hot air from engine exhaust, meet the freezing cold air at altitudes of 30000 feet or more.
If you ever see a commercial airliner in flight behind it there will be a white tail folowing it. This is the smoke trail.
smoke
It's the fuel from the engines.
some kids taught it how to smoke behind the shed.
When you see a white trail behind an airplane, that is what is known as a contrail, short for condensation trail, and it is composed of water vapor, not smoke. This condensation happens because the hot exhaust of the plane's engine meets the colder surrounding air and the mixture of cold and hot air is a sort of miniature weather front.
Condensation in the low temperature atmosphere of vapours found in the engine exhausts. Its name is a Contrail - condensation trails.
white smoke is water, black smoke is oil. remember that!
There are two kinds of 'white-smoke'. If it dissipates quickly into the air, its just steam (water) no big deal if it goes away in a bit. The second is the kind that hangs in the air and leaves a cloud behind the car. That's OIL. That's expensive!!
white smoke is coming from my exhaust why?
white smoke is water. head gasket or ?
White smoke normally means you are burning oil.
white smoke can be either your car overheating, or smoke from an electrical issue