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#1 | |
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There are no government planes flying that spray chemicals into the air for any reason. The planes you see on such "irregular patterns" are mostly commercial airliners either coming from Europe over the Atlantic. What would you consider "regular patterns"? Do you know what the “regular patterns” are? Then how can you say what “irregular patterns” look like? Contrails are of condensed water vapor made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets. If the air is cold enough, this trail will comprise tiny ice crystals. The reason they get bigger is the wingtips of the plane create wingtip vortices, also know as wake turbulence which creates two columns of spinning air behind the airplane. This is what causes the contrails to spread out and dissipate. (The winds aloft help too) When people see rainbows in the contrails they assume they are chemicals and that the government is to blame. Get a clue Actually, you'll see more contrails when there is more upper atmosphere mositure. When the moist air is heated in the engine, then cools as it exits, the moisture is what freezes into ice crystals and becomes the contrail |
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#2 | |
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#3 | |
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#4 | |
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Years ago, there was not as much traffic flying. And StephenB yes, what you said about contrail is also true, thanks for the added info. |
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#5 | |
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I didn't realize that in this heightened-awareness kind of world, that the hush factor extended to staff now too. ![]() |
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#6 |
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Two observations that complement the conversation here.
From time to time at work, I get to see air being evacuated from vacuum chambers and it is always amazing how much water vapor condenses out of the air during the pressure drop. A cloud bank forms in the chamber. My understanding is that the temperature drops from the pressure drop. Another demonstration of the pressure drop causing condensation can be seen sometimes on the tip of an airplane wing where no combustion is going on. The pressure increase as the wing approaches changes to a pressure drop on the other side and you can see the vapor trail. |
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#7 |
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Well, Samiam, guess you and I are the only "kooks" on this forum. No one will convince me there is not a difference, so it will just have to be.
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#8 | |
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The planes continue to fly as a distraction. If and when any investigative study is ever done, you would find that all modern military planes have 100% inert exhaust gases as it relates to mind and population control substances.
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#9 | |
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#10 | |
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The Sky is Falling...............................The Sky is Falling!
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Just Sold ![]() At the lake the stress of daily life just melts away. Pro Re Nata |
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#11 |
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About this time of year, every year, the subject seems to pop up in various places. I think trfour nailed it with this link http://en.wikipedia.org/wiki/Contrail Take a look at the changes in the upper atmosphere this time of year, dew points are lower, temps are lower and the contrails last much longer. Maybe someone like Rose, who understands the atmosphere better than most of us, could give enlighten us. On clear days the upper atmosphere is dry and contrails persist.
Several years ago there were a lot of stories and letters to the editor in the Conway Daily Sun about contrails and one gentleman in particular was convinced it was a government plot.
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#13 | |
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Eventually, the moisture disperses into the surrounding, somewhat drier air just enough to no longer drop below the dew point and the contrail basically dries back up. How long this takes might be bit of a function of the aerodynamics of the plane and engine, which determines how well the exhaust gasses mixed into the local atmosphere. Mainly, however, it's a function of how close the atmosphere was to the dew point before the jet passed by, as well as what the prevailing winds aloft were after the plane passed by that determine how long the elevated moisture trail takes to dissipate, dropping the dew point again. Sometimes the contrails last a minute or so after the plane passes, (indicating a medium amount of pre-existing water vapor), sometimes there isn't any contrail at all, (indicating a "dry" atmosphere at that flight level), and sometimes they can last an hour or more (indicating a more closely "saturated" atmosphere. If the air is already completely saturated, you already have visible moisture, aka a cloud. ![]() Again, it depends mainly on how close the atmosphere already is to the dew point before the plane passes through the area (and at the altitudes typical of contrails, "dew" usually means ice crystals, which I suppose might last even a bit longer afterwards too.) |
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