why some high flying jets leaving 2 continous lines of white clouds behind?

Answer 1

That's jet exhaust. Two indicates there are two engines on the plane.

Have a great day!!!

Answer 2

Contrails are not airplane exhaust. They are ice crystals formed by the freezing of water in the air.

Planes fly because there is more air pressure below the wing than above it. At the edge of the wing, air pressure can leak from the underside to the top. This causes a vortex.

At the center of the vortex there is an area of very low pressure. When pressure goes down, the temperature goes down. Water in the air freezes.

If you want to see a great example of wingtip vortices, watch Die Hard 2. At the end, when the planes are landing in all the smoke and fog, there is a beautiful vortex that knocks Bruce Willis off his feet.

Answer 3

Please do not take what I say as an insult! These trails are condensation of water vapor produced by jet engines that require a concentration of air in order to operate at the high altitude you mentioned. At high altitudes air is thin. The engine, which is burning refined fossil fuel, needs lots of air. To accomplish this, air must be heavily compressed before entering the engine to aid in burning of the fuel. The result is water vapor, which has been expanded under fire (propulsion) to be left behind as trails.

Another post mentioned global warming. Trails that might do that are called Chem-trails, chem being short for chemical. It is suspected - and I say again, suspected - some high flying aircraft, usually military, actually release chemicals into our atmosphere for some unknown purpose. These "chem-trails" are said to last, or linger, significantly longer than trails thought to be mere water vapor. You can research what I'm telling you on-line, just goggle it! Type in "chemtrails" and I guarantee you'll get a hit!

Answer 4

a number of those are fairly creative suggestions and no longer fairly close the actuality. basically assume - the exterior air temperature on the altitude that those airplane are flying at is around -40deg C. it is fairly below the freezing component of water, and correctly above cloud degree, so there is not any water vapour reachable to purpose those trails. What you're seeing is the end results of the gas being burnt, the engines produce water vapour as a manufactured from burning hydrocarbon fuels in precisely an identical approach that any vehicle will produce a white vapour greater obtrusive on chilly days. White trails that are obtrusive coming from the information of the wings get up at lots decrease altitudes, frequently whilst the O.A.T. is basically above freezing. they are triggered by making use of skill of the bigger rigidity air below the wing (sic) passing to the shrink tension undertaking on the precise of the wing. they are many times very short lived and are many times referred to as 'wing tip vortices' that maximum ordinarily adjust to a spiral direction removed from the wing tip. desire this facilitates

Answer 5

I saw a show on Discory about these 'Contrails' and believe it or not, they are contributing a lot to global warming. Basdically they are just plane exhaust. These contrails reflect light back to earth that has already bounced off of Earth creating a warmer environment.

Answer 6

They are contrails and they are caused by water vapor from the jet's exhaust cooling and condensing.

Answer 7

Two large jet engines side by side.

Answer 8

Yes, I agree. stuart r is the man. Give him the best answer 'cause he is right on the money. U go stuart

Answer 9

Maybe because they have 2 engines?

Answer 10

The temperature up there is so cold that the exhaust condenses so it's visible.