Why do some planes leave trails of cloud (smoke ?) in the sky but others don't ?

Question

I have always wondered about that. does it have to do with the height of the flight ? Type of plane ?

Answer 1

"To make a vaccine?" I queried.

"No. To spray us."

"Spray us?"

"With contrails. Millions will die."

"Contrails? Really?"

"The government's been doing it for years. They've already been spraying us to make us dumber."

"I've been feeling dumber," I responded with a smile hoping desperately for one in return, "but I didn't think it had anything to do with contrails."

"12th graders today are testing lower than 9th graders in the rest of the world."

When I got home, the first thing I searched for was information for "contrails flu." In Yahoo, there were 7,780 results; in Google, "about 12,000." It appears that this guy isn't alone in his beliefs....

Answer 2

the path at the back of a plane comes from vapor this is produced for the time of the substitute in temperature for the time of the engine. At 30,000 ft the air temperature is around -37c and as a effect an engine with an inner temperature of 1500c will produce fairly a lot of water vapor. some circumstances the relative humidity at altitude is fairly low and as a effect no seen trails may well be seen from floor point. On different events the kind of engine will produce a distinctive effect and back it fairly is no longer a important.

Answer 3

You are referring to an jet's contrail which is warm water vapor. It is exactly the same thing that leaves a car's tail pipe on a cold day. To be visible, the water vaport must change to minute droplets of water. And like the car's water vapor on a cold day, sometimes the water vapor and the contrail lasts longer than at other times. " The length of time that a contrail lasts is directly proportional to the amount of humidity that is already in the atmosphere. A drier atmosphere leads to a more short-lived contrail, while an atmosphere that has more humidity will lead to longer-lived contrails. However, if the atmosphere is too dry, no contrails will form. Occasionally a jet plane, especially if ascending or descending, will pass through a much drier or more moist layer of atmosphere which may result in a broken pattern to the contrail, with it appearing in segments rather than in one continuous plume."

http://www.wrh.noaa.gov/fgz/science/contrail.php?wfo=fgz

Answer 4

Those trails behind aircraft are called 'contrails.' They're caused by moisture in the exhaust from the plane's engines freezing. Whether they appear or not depends on atmospheric conditions at the altitude where the plane is flying, like temperature, air pressure, humidity, etc.,.

Answer 5

They're called contrails.

According to Wikipedia:
"Contrails or vapour trails are condensation trails and artificial cirrus clouds made by the exhaust of aircraft engines or wingtip vortices which precipitate a stream of air crystals in moist, frigid upper air."

For more see:
http://en.wikipedia.org/wiki/Contrail

Answer 6

I think it is when the plane is at high altitude, and the sky is really cold, and the gasses coming from the plane condense, making cloud like trails.

Answer 7

it depends on what height they are at. the cloud trails are beacuse of the heat of the engines vaporizing the air and making the water in the atmosphere condense around it. It happens at different altitudes

Answer 8

It has to do with the altitude and the humidity where the plane is. If the humidity is low, the water in the exhaust just evaporates. If the humidity is somewhet high, the water condenses and forms the trail.

Answer 9

what the other people say is right and there is also this conspiracy theory that the planes are seeding the air for some reason.