Why do some airplanes leave very thick trails in the sky?

Question

Often an airplane will leave a thin vapor trail in the sky behind its jet engines. Other times, there is a very thick "cloud-like" trail they leave behind. A friend tells me the thick trail is because they are doing some type of chemical spray. I don't think so, but I don't have a better explanation. Can someone give me the information to convince her the government isn't trying to kill us with chemicals?

Answer 1

Unfortunately, I dont believe it either, but a lot of people do.  My uncle is a fantatic about it and thinks the same ways your friend does. He calls them chem trails, I dont have an explanation though, I was always told that it was the exhaust coming out, but no matter the real answer, how would anyone be able to stop it... its the government they are FISHY and thats why the economy is the way it is.

Answer 2

Just want to add that a turbo-jet engine will leave a different-looking water vapor trail then a turbo-fan will, even when flying side-by-side. Sometimes this is mistaken as proof of a spraying conspiracy.

Although there is evidence of some sort of spraying operation including barium and aluminum dust, I can assure you that commercial airlines have nothing to do with it. It's purely a military thing if anything.

There's information out there to be found on the subject, but be careful. There are a lot of ridiculous ideas because this sort of thing has a tendency to attract complete nut jobs. You'll see what I mean if you keep investigating.

Answer 3

It usually depends on the conditions. Vapor trails come from two things. First is the water vapor created by burning jet fuel. If the air is the right combination of cold and density, the vapor will condense into a trail. It can also come from the low pressure in the wingtip vortex. The wings of an aircraft cause a drop in air pressure in the vicinity of the wing. This brings with it a drop in temperature, which can cause water to condense out of the air and form a vapor trail or contrail. However, the vapor trails do contain pollutants that can harm the atmosphere. Basically, airplanes release the same vapor trails, it is really to conditions that make the look of it change, like temperature, the density, attitude, also the the amount of fuel being burned, and many more factors.

Answer 4

there are not spraying the town its just the gas that got burned you know the stuff that comes out of the rear of your car that just the same but they use a diffrent type of gas so it does bot go into the air

Answer 5

Contrails are cloud  trails.  

They're mostly liquid or solid water.

When they evaporate or sublimate they become water vapor.

Answer 6

Additionally, irregularities in the surfaces of an aircraft (hinges, rivets, joints, panel seems, lights, curves, missile parts and pylons on fighter aircraft) all contribute to collecting and condensing water vapor that eventually falls off at a streaming rate.  While there are exhaust-related polluting components in a contrail, the vast majority of its content is water vapor.

The relative "thickness" or "thin-ness" of the contrail is dependent on altitude, temperature, density, winds at altitude, and the aircraft's individual characteristics (shapes, engines, etc.).  Because large bodies of air have characteristics that promote contrails, it is possible to fly in an out of the "cons" by changing altitude alone.

Answer 7

haha

its not chemicals

its called a paper trail its just exhaust

usually happens in small personal jet planes

it also happens if you overspeed a plane

Answer 8

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 tiny ice crystals in moist, frigid upper air.