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Planes through clouds and no evidence.

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Planes through clouds and no evidence.

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Old 29th Apr 2008, 15:50
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Planes through clouds and no evidence.

Sounds strange but I wonder if anyone can help with this concept that has been bugging me for some time. Why is it that from the ground when you see an aircraft enter cloud and then exit that cloud the cloud stays absolutely still and the bits of cloud don't appear ruffled in any way? Surely the aircraft and its wake turbulence would show up in the cloud as the aircraft leaves it? All replies much appreciated.
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Old 29th Apr 2008, 16:07
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Search on Paul Bowen.

Find his home page.

Enjoy

Rob
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Old 1st May 2008, 12:41
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The effects of an aircraft's wake on any cloud it flies through is generally too small to be seen from the ground.
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Old 2nd May 2008, 00:35
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Flying in a formation of C130 Hercs in and out of some cloud, I have seen the cloud "shape" to the slipstream of the four engines as the aircraft enters the cloud.

It looks pretty impressive as the cloud forms a helix type shape behind each of the engines. But I doubt you could see the change from the ground.
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Old 2nd May 2008, 10:24
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With a low layer of overcast cloud, i.e tops at 2000-ish feet, you can generally see the 'furrow' carved by aircraft on the ILS.
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Old 3rd May 2008, 03:16
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Very nice photos on that site, PPRune Towers.
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Old 3rd May 2008, 17:58
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Its the same phenomenon that occurs when you look at steam or smoke from a chimmeny or power station from a distance away, and the white clouds from the tops do not appear to be moving at all.

But when you get up close, you can see a lot of cloud pouring out the top...

No, I dont know what causes it.
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Old 12th May 2008, 13:45
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Thanks thats cleared things up a bit!
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Old 14th May 2008, 03:13
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It may help to think of the cloud as a constantly changing and moving phenomenon. When an airplane flies through it, a hole isn't created. The consistency throughout the cloud with respect to visible moisture and reduced visibility is fairly constant at a given level. What this means for the observer is that as air swirls in the cloud, it draws more vapor...it fills in the "hole."

From the ground you see a cloud with rolls and tucks and edges and swirls; the cloud takes on a changing appearance with shadows...which hide the character of the cloud as you might see it up close.

At the cloud level wind blows, and the clouds appear to move with the wind. In reality, the wind blows through the clouds, which are constantly dissipating and forming...not just puffs of vapor blowing in the wind.

If you were able to sit next to the exit point in the cloud when the aircraft comes out of the cloud you would indeed see the cloud swirl in the wake of the exiting airplane, but that's hard to see from the ground.

I've flown formation with other aircraft in and out of clouds, above them, beneath them, and so forth, and the atmosphere is visibly disturbed by a passing aircraft...but being very far away makes it nearly impossible to see.

You may see this sometimes from the air, if you're riding in an aircraft and pass close to the contrail of anothe airplane, or see one pass by when you're near a cloud...you may get to see the cloud disturbance first hand.
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