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Vapor Trails and Cones

Posted June 24, 2012 12:57 PM

From The Presurfer:

These pictures of plumes of air billowing from the back ends of aircraft may seem like a cause for concern. But these images actually show spinning vapor trails created by cold air circulating around the wing.

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Tornado
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#1

Re: Vapor Trails and Cones

06/24/2012 9:41 PM

The pix are beautiful, but the explanations aren't quite correct.

1. The helical (not conical) contrails come from vortices at the propeller tips.

2. The air may already be cool, but the reduction in pressure causes further cooling, and hence condensation of water vapor into a visible fog of droplets spiraling off the wing (or prop) tips.

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Re: Vapor Trails and Cones

06/25/2012 3:36 AM

I agree on both points:

The pictures are beautiful and definitely worth viewing.

The explanations are lacking and much improved with Tornado's corrections.

I would add that the water vapor resulting from fuel combustion has a significant effect on the visibility and longevity of contrails.

Also, if you need a good laugh, a flock of chem-trailers have marked the comment section below the linked article with their typical zany flavor of pseudologic.
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#3

Re: Vapor Trails and Cones

06/25/2012 7:27 AM

I like the pics of the US Navy F-18F Super Hornet the best, followed by the F-22A Lightning II (ie, the Raptor)....

Incredible pics all

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