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Why Planes Make Vapor Trails

Popular Science, March 1943. Page 55.

While this applies to 1943 planes, it should also be noted that the exact same mechanisms are responsible for contrails from modern jet aircraft. Jet engines burn fuel that is essentially the same kind of chemical as used by old prop planes. They produce lots of water vapor, and a contrail can result if the weather (at the plane’s altitude) is right. If the weather aloft is humid, then the contrail can persist for several hours.

262 thoughts on “Why Planes Make Vapor Trails

  1. You could (and I’m thinking of ways of how to get around an implausibly super powerful AI net censorship robot here) handwrite your secret on some paper, scan it in, and post it on Flickr.

    It’s impossible to censor the US internet 100%.

  2. rising sun says:

    i dont care for any psychology games you have because that game of chess im two steps ahead of you. all i care about is research, eyewitness accounts and most of all, motivation. i dont like you disecting words such as perfect coverup. what i meant by perfect was near perfect and so far one of the best setup ones and most backed

  3. Okay, so you say that ATS is dupe site, fed deliberate disinfo by the government? So all this chemtrail theory is just disinfo to cover up something else?

    Sounds a bit circular. Where’s the actual evidence of ANYTHING? Your plants have powdery mildew?

  4. MikeC says:

    Maybe it isn’t impossible, but it is perilously close to not english – or at least not useful in terms of getting your ideas across – I find your posts increasingly difficult to understand – the last few simply make no sense to me at all – I understand the words but the sentences have no meaning! 🙁

  5. If you are two steps ahead of me, then what’s my next step?

  6. rising sun says:

    not if they just “suggest” flickr remove it. and besides there are top secret and above top secret inteliigence and counter intelligence programs that probably go above website administrators. its not that hard to see how someone as powerful and rich as the bankers and government and so on could set everything up and be able to move behind the curtains without people knowing. its what they do best and what they havve to specialize in nowadays with all the technology. its not the limitations that movies put in our heads. its the limitless possibilities someone with money and power can have and how to reach their goal.
    The continuity of current powers power by any means necessary.

    thats what my mind has come to believe.

    i dont believe there are angels out there guiding heros into leadership anymore cuz any dumbass whos willing to be evil enough will have power through their desire.

  7. rising sun says:

    ” Where’s the actual evidence of ANYTHING?”

    oh come on uncinus dont tell me youve forgotten everything weve discussed.
    wheres the brain flexing bro?
    ya i remember cuz im genuinly concerned.
    is this some hobby where you live in the present and do not take history into consideration. if so then my time has been wasted on those who arent even paying attention

  8. MikeC says:

    If flikr took something down then you would know it had been taken down – where are the reports of censorship? there’s also facebook, twitter, blogs based around the world, any number of smaller forums, newspaper comment columns, etc??

    Here’s why trying to suppress stuff simply does not work: http://depletedcranium.com/why-beneficial-discoveries-cant-be-kept-down-even-by-big-corporations/

  9. not if they just “suggest” flickr remove it. and besides there are top secret and above top secret inteliigence and counter intelligence programs that probably go above website administrators. its not that hard to see how someone as powerful and rich as the bankers and government and so on could set everything up and be able to move behind the curtains without people knowing. its what they do best and what they havve to specialize in nowadays with all the technology. its not the limitations that movies put in our heads. its the limitless possibilities someone with money and power can have and how to reach their goal.

    But clear there would also be no evidence of this happening. So you are entirely basing your supposition on “it sounds like something they would do”.

    There is absolutely zero evidence that the web is being censored by the government and big corporations in the way you suggest. Everything indicates that if someone wanted to get information out, they would have no problem in doing so. See Wikileaks for an extreme example.

    Everything is NOT an illusion.

  10. slave3654812390 says:


    I’ve been reading your rubbish on the net FOR THREE YEARS NOW. Hope they pay you well. You should probably get some different user names…. you’re starting to pop up in Google a lot.

  11. MikeC says:

    He’s clearly establishing a reputaion for his name & when you see it you know what you are getting – science.

    that sounds like a good thing to me – why should he change it?

  12. slave3654812390 says:

    Well a bit of searching in the right areas will find what info you seek on these debunking mob.
    If their not paid/ rewarded for there efforts then it’s a very lonely life.

    Of course most of us are aware that software enables the generation of mass user accounts across forums such as Twitter and Youtube, this site and so on.
    The idea that all this conjecture may be coming from just a handful of people and spread en-mass is now becoming quiet apparent.


    Forget psy-ops for a second…. my concern is much deeper.
    What happens when their psy…. pops?
    Happens to the best of em.
    If they keep this up for too long the reality they fear others have lost may also become their undoing.

    Take it from a loony like me… it appears from where I stand that the bow doth break.

  13. SR1419 says:

    Since when is physics “conjecture”?

    ..and how is asserting that their is a global, clandestine “spray” campaign of unknown intent…NOT conjecture?

  14. slave3654812390 says:

    Is that your rebuttal? Seriously?
    … I’m not talking about the spray campaign… I’m portaining to YOUR stability.
    How long before one of your peers goes and does something “rather rash”.
    The “con” trail you guys are leaving behind you is unfortunately not dissipating like you probably had hoped.

    In fact a new reality now exists.
    One that uses you to breath.

    You really don’t get it, do you guys?
    It’s like your work boots. Sullied from others waste, they are kicked to the corner daily for preference of more comfortable shoes at night.
    But somebody’s been sharing your shoes at night.
    We now have a fungus that spreads.

    Now they have come for you good shoes.

  15. SR1419 says:


    thats it?

    Weak prose instead substantive discussion?

    Clearly, it is you who does not get it…but I will leave that for you to figure out.

  16. MikeC says:

    There’s real irony in slave’s arguments – they apply so much more obviously to the chemtrail hoaxer’s – all the evidence you ever get is the same stuff rehashed from years ago, it all goes back to Carnicom, Rense, Tanker Enemy – if not in actual content then in style – unsupported assertions of various evils that never sem to quite manage to have any concrete evidence.

    And of course all of whom have been shown to be inadequate as sources of verifiable information, but they keep repeating it as if that will make it true.

    And we do know they are getting paid for it from their merchandise – books, video, advertising – it is in their interests to keep people buying!!

  17. slave3654812390 says:

    Rense.. pffft. He’s got nothing on me!

    Well what I was trying to say is… I hope this guy aint one of yours.
    It appears he’s causing quiet a stir, not doing your mob any favors though.

    Take time to read through all the fascinating threads, should not take you too long.


    See ya… yuk yuk.

  18. imakeopsname2 says:

    chemtrails are contrails

    imnot one of them or one of him

  19. imakeopsname2 says:

    “persistent contrails”

    why name something that already had a name?


  20. It’s to describe what type of contrail it is.

  21. imakeopsname2 says:

    how many types of contrails are there?

  22. Three, if you are just looking at persistence and spreading of exhaust contrails.


  23. See this chart which explains the conditions required for formation of each type:



  24. That chart, BTW, is excellent for illustrating a key concept of contrail fromation: that of “mixing”. It also (if you can follow the graphs) shows why the type of engine (and specifically the exhaust temperature and moisture content) have an effect on the contrail formation.

    You can also see, if you move point A (the ambient air state) into hotter and/or dryer air, how you can get a “nontrail”.

  25. imakeopsname2 says:

    i guess nasa and the government thought it wasnt relevant to categorize low altitude contrails either? whys that?

    must not be relevant ;/

  26. You can describe any type of contrail just by putting a descriptive word in front of it, hence, as you just did, “low altitude contrails” ARE a typ of contrail.

    NASA does not talk much about them because they are very rare, and they don’t have much impact on climate. They do exist, but only in cold places.

    What you saw was almost certainly not a contrail, or if it was then it was not low altitude.

  27. imakeopsname2 says:

    you dont need to delete the comment.

    its relevent to contrails in that i saw “persistent contrails” at ground and foot level.

  28. You saw something. It’s nearly impossible they were “persistent contrails”, in the sense of being condensed water vapor from aircraft engines.

    You’d think if such things existed, anywhere in the entire world, then there would be photos of them on the internet. But no. Or did what you see look like any of these images?


  29. imakeopsname2 says:

    lol no but let me use one of those pictures to describe it.

    like this prop plane, not necessarily the make, but the eyescope of the vehicle is crucial and thats what my eye saw, at night, right over me head 😀

  30. imakeopsname2 says:

    and saw previous to that multiple times but my memory fades so i recollect the concept of it happening during the day and a few times at night. and before the night during the day they would prep the skies for the “night flight”

  31. imakeopsname2 says:

    thats what im saying uncinus it isnt condensed water vapor or ice crystals part of a tranluscent ice field in the upper troposphere. its down here bye yer ead man

    a fraction of the spray ops would obviously have a real science so as to appease the “intellectuals”.
    but lets take a step back and say

    contrails are REAL

    thats what i think. sure contrail science IS science. but the science of chemtrails is something you cannot speak of or literally dont know of… ive been to plenty conspiracy websites and their not all bad but i think most are. and most are structured on like you said some supposition that nearly noone can prove.
    but i cant do anything but speak and act. so what use is the thinker in me? is that what everyone is saying? are people assuming things based on a deeper sense of the planet&univers due to strange nuerology? you would say so uncinus right? i personally dont think its anything other than the coincidences and occurrences stiring the populous. their all moving around like cattle in a dark unmoving slaughter house, huddling and we dont even know where we are, and what is happening. please dont delete this comment, its very relevent to the science basis for contrails with an unknown area of secret clearance of specialized meteorologists, bio/chemists, genetics, and many popular amongst the rich and powerful as some crazy belief in sucession into a higher complexity through chaos. thats not what happens. everything is one giant clock. the more you wake up to the nefarious plans that are undisclosed to the public probably for national security for the public and the GOVERNMENTS stability. whatever it is youve been “educated” i want you to pls stfu for one gosh dang second.

    think long.

    what is possible and wheres our population and consumption of our population going RIGHT NOW?

    your perhaps a pig roasting after being fattened up and tamed.

  32. imakeopsname2 says:

    its kind of like,


    if you could create other accounts and give them all an alias random or reappearant, would you?
    is it possible to help spread your contrail science in that fashion.

    and dont forget i have to remind you its about chemtrail disinformation or contrail science for my comment to pass your pre-emptive validation.

    pls dont delete all the above comments. i saved and would prefer to keep it reasonable that all the above mentioned facts are because i experienced persistent contrails at foot level but they werent contrails because that was for a while in saint george utah while the “remote” airport on the plateau was closed down this past new year 2011 due to an international airport opening.

    for saint george?



    all the above comments are necessary for my search for what chemtrails are or other technologies patented for most likely nefarious reasons undisclosed to the public or in any high ranking military/scientific feild.
    -all recovered from low chemtrails from prop planes ranging from single, bi, and quad engine proppellor planes some distinct and fast, others bigger prop planes with no large labeling or clear route upon taking off and flying above the city dispersing “chemtrails” then coming back in for a landing and im posed on the hill north of bloomington walmart, hundreds of yards south of the airport takeoff on the southernmost track end/takeoff.

    you took away some of my rights because you felt like it.

    and the internet gathered from your website and conspiracy websites and common sense plus some science and its as simple as taking temperatures and checking altitudes.
    i dont really care for any websites out there.

    yours is the only competitive one >:)

    lol must be a long day cuz we talked before about this. at least i was aware that you hadnt however many days ago you first began commenting

    and if a roof needsa fixin bitch quit bitchin about it and git to werk! (c >,>)_!oO

  33. Janet Detwiler says:

    @ imakesopsname2 ~ My name is Janet Detwiler. I live in Seattle. I’m a 53YO female. A simple Google search will verify that.

    Thank you for your concern regarding my roof. I live in low-income housing, so fortunately and unfortunately it is not something I can fix. But I am glad you got a chuckle out of my misfortune, I guess.

    I still have not gotten a response from you at my personal email address concerning this video camera. ONE MORE TIME ~ [email protected] ~ I think Uncinus is right. I don’t think this old 80’s dinosaur would be of much use to you. But this is the last time I’m going to say this; write me at my personal email address (again, you’re welcome), and we can talk about shipping it to you if you want it.

    I feel very bad for clogging up this stream with this nonsense. My apologies to all. Please delete any and all comments as you see fit.

  34. imakeopsname2 says:

    i think im gonna pass on the old vhs but thanks for your time.

  35. imakeopsname2 says:

    how tall from a minimum to a maximum elevation do the warm air waves or blanket that is below the cold air needed for contrails. i would imagine a big large area of the atmostphere is warm air so what do it look like at the lowest point of the wave and the highest climactic point from that wave in miles pls.

  36. imakeopsname2 says:

    wave being warm air beneath cold air. and the effects of hitting a large one. would large ones form at the poles and if so what are the forces if any of those colder regions where the warm air atomsphere is naturally thought by me to be under the cold contrail forming air to a point of cold contrails at ground level. and also does the electromagnetic feild affect the weather as such explorative questions? the warm air could-to me- almost look like the inner shell of the electromagnetic feild? are there parts of the magnetosphere missing from the poles? how does it affect a plane going through such air waves and or electromagnetic change/loss?

  37. imakeopsname2 says:

    also tell me what the 2 objects on each wing towards the middle and end of the wing or right and left of the engines in this picture.?

  38. imakeopsname2 says:

    now explain this img that looks similar to the NON-engine objects under the wing;

    then explain this past contrailers video post;

  39. imakeopsname2, your images are not showing up. Try using [img] tags, or upload them directly in the form below, or just post the plain URL.

  40. MikeC says:

    Can’t see any pictures, and can’t make any sense of you posts before you say you’ve posted the pictures sorry.

  41. imakeopsname2 says:

    well whilei find them again can you answer the atmospheric q’s i posed?

  42. Are you talking about fronts? Do a search for images of “warm front” and “cold front”, that might illustrate the issue for you. Then maybe you could re-phrase the question, as it’s not really clear.


  43. MikeC says:

    Why don’t you search on the internet for the answers?

  44. imakeopsname2 says:

    this is the internet smart one

  45. Searching is different to asking.

    But. You might want to look up “lapse rate”. That’s how quickly it gets colder as you go up. Basically every 1000 feet, the temperature drop 3.5F. So there’s no height of the warm air, it just gets gradually colder as you go higher (eventually it levels off, at above about 36,000 feet, then increases, then decreases).

    Here’s a graph of temperature against height. It’s not too relevant to contrails though, as they form mostly around the tropopause, down the bottom.


  46. imakeopsname2 says:

    im talking about the wave formation at around 40 degrees fairenheit that you talk about as the cause for the on/off of persistent contrails

  47. imakeopsname2 says:

    ur graph is saying 70 miles up is 120 degrees fairenheit btw

  48. That’s right. Not something you’d expect, right? And it gets a lot hotter. Of course the atmosphere at 70 miles up is pretty thin, so it’s not exactly the same kind of “temperature” as on the ground. See Wikipedia:


    The highly diluted gas in this layer can reach 2,500 °C (4,530 °F) during the day. Even though the temperature is so high, one would not feel warm in the thermosphere, because it is so near vacuum that there is not enough contact with the few atoms of gas to transfer much heat. A normal thermometer would read significantly below 0 °C (32 °F), due to the energy lost by thermal radiation overtaking the energy acquired from the atmospheric gas by direct contact.

  49. imakeopsNAME2????? says:

    what about agent orange? and others? probably researched in wwII and no more than implemented in the 1950s and 60s like in vietnam per instance…?

  50. What about Agent Orange? Did you read about what it was?


    Are you saying that because the government sprayed defoliant 40 years ago, and it turned out to be toxic, then somehow they must be doing something similar now? (but apparently totally undetectably, and without any effect).

  51. John says:

    If a CLOUD of water vapour comes out of a jet engine, it will linger for a few seconds, it will last all day, it will blow in the wind, other trails will interact with it and make strange looking patterns, it will be patchy (start & stop), it will spread out and cover the sky.

    The point i’m trying to make is;
    How is a cloud of water vapour supposed to act any differently to any other cloud you have ever seen?

    It’s as simple as that.

    I am inviting any chemtraillers to dis-agree with the above statement.
    I have no doubt that they will all miss the point somewhat…

  52. imakeopsNAME2????? says:

    clearly the defoliant affect is occurrent and did you see the harmful side effects of those that were called the most dangerously engineered molecule known to man. the side affects and defects looked as bad as nuclear radiation. the defoliant effect has been documented by me as you know and if its as toxic as they say you and the gov would be liable. you for disinformation, them for high treason. maybe you worse

  53. imakeopsNAME2????? says:

    ill disagree heartely because you obviously didnt read jack shit because your such a know it all john. i saw unmarked large silver and white as well as several other prop planes in a rural city that were flying under 5000ft. dispute that with your contrail science genius.

  54. imakeopsNAME2????? says:

    if youve done even a minute amount of research you would know that contrails let alone the PERSISTENT CONTRAILS that appeared from behind the prop planes below 5000 ft are not possible in my region. i dont care if i have evidence but you cannot dispute my account.

  55. TJ says:

    imakeOPSname2?: Small airplanes that take off and land quickly after takeoff are practicing landings. It’s not a waste of fuel, time, and money, as pilots gain valuable experience by doing these “touch-and-goes”.

  56. TJ says:

    imakeOPSname2?: How do you know they’re below 5000 ft? And prop planes, especially turboprops, are very capable of producing contrails.

  57. TJ says:

    imakeOPSname2?: That picture of the red airplane you say is emitting a “persistent contrail” is actually an airplane used for aerobatic maneuvers. It uses a smoke machine to emit smoke so that crowds can more easily track it as they are watching the pilot perform.

  58. TJ says:

    imakeOPSname2?: Those two objects under the wings of the red airplane you posted are its fixed landing gears.

  59. Harvey Gallop says:

    This site really lacks any scientific detail. How cold does it have to be in the upper atmosphere to create contrails that persist and spread out across the sky. I notice it occurs even on days that are nearly reaching 40 degrees.

  60. about -40 or below. It’s always that cold at some altitude. But you also need humidity.

  61. JFDee says:


    the temperature in the altitude where commercial jet traffic usually occurs is very different from the temperature on the ground. Look for stories about stowaways in planes who discovered this the hard way even when they took off in a hot climate.

    If you prefer science, read this:

  62. Ledmore says:

    This is definitely an interesting debate. I want to thank the original posters, and all who have written interesting commentary.
    I have recently been introduced to the contrail/chemtrail debate. Being a student of science, I have always seen contrails as hyper-condensation. The more I looked into the meteorological facts of condensation, and how airplanes interact with the atmosphere, the more I find the chemtrail theory, well, silly. Im sure I speak for others here, including Uncinus, the government has experimented with weather control. It seems a worthy endeavor. I have not done much research on its success or failures, so I wont speak to it. The meteorological science of contrails is sound, and easily observable and provable. Put a fan in front of a air conditioner, blowing away from the AC unit, and turn on both units in a humid room.
    Someone else here makes another valid argument, stating contrails are real and natural, but why cannot chemtrails also exist.
    My question is, why would they exist?
    Is the government really trying to enforce population control and food production limitations to push a secret agenda, or are some of us caught in this ‘UFO’ frenzy? What seems more logical?
    Im staying with science and logic on this debate. Therein are the facts and evidence, contrails being simple atmospheric phenomena. Chemtrail supporters spout lots of ‘sightings’ and supposed evidence in the form of youtube vids…? Someone else made the comment here, dont use a youtube video as evidence. Many are completely unsubstantiated.
    This entire post has been good reading for an afternoon. Im staying with science and logic. My friend will continue to state much of the same inanities as I read here to ‘support’ their argument of chemtrails, and thats fine, I welcome good debate.
    It should also be noted that this debate could easily devolve into the science vs religion debate. If you base your entire argument on a work of fiction, well, you all know the rest….

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