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What Are Contrails?

Since the dawn of the aviation age, a new type of cloud has been appearing in our skies. Cirrus aviaticus clouds, more commonly known as contrails, are now found crossing the skies over nearly every populated part of the world.

Contrails, short for condensation trails, are the clouds that form in the wake of a passing aircraft at high altitude. Sometimes these clouds dissipate quickly, and at other times linger for several minutes after the plane has passed. In some cases, contrails can spread, forming wispy blankets in the sky as they mix with other contrails.

Though some observers find these man-made cirrus clouds beautiful, others consider them an unwelcome pollutant spoiling our pristine skies. Climate scientists have taken an interest as well, hoping to better understand the environmental impact of these artificial clouds - and the hydrocarbon-burning airplanes that produced them.

Contrail formation guide - when airplane exhaust B mixes with atmospheric conditions A, a contrail will form if the line between them crosses the condensation curve - the solid blue line.

Contrail formation guide - when airplane exhaust B mixes with atmospheric conditions A, a contrail will form if the line between them crosses the condensation curve - the solid blue line.

Chart created by National Weather Service scientist Herbert Appleman to forecast temperature and pressure conditions for contrail formation

Chart created by National Weather Service scientist Herbert Appleman to forecast temperature and pressure conditions for contrail formation

Why Do Contrails Form?

Simply put, a contrail forms when the hot water vapor and exhaust gas from a jet engine combines with water vapor in the extremely cold environment of the upper troposphere. The water vapor solidifies into trillions of tiny ice crystals in a process known as deposition.

A passing jet engine creates an artificial cloud by mixing hot moist air from the exhaust with the sub-freezing humid air it is passing through. You can observe a very similar mixing cloud by exhaling on a cold winter day - warm water vapor from your breath combines with water vapor in the air and condenses into tiny water droplets to form a breath cloud.

Contrail formation is a more extreme version of this mixing cloud since the difference in temperature is far more extreme at airplane cruising altitudes. Generally, contrails form when temperatures are below −40°F (−40°C). Jet engine exhaust emerges at about 1560°F (850°C). As the super-hot air from the jet engine mixes with the super-cold air of the atmosphere, it rapidly cools, causing its own water vapor - and the water vapor already in the surrounding air - to condense into water droplets and then quickly freeze into tiny ice crystals.

This only happens under certain conditions, however. Contrails only form when the air at cruising altitude has just the right mix of air temperature, air pressure, and humidity. Since the atmosphere is not uniform, these can change over different areas and at different altitudes. This is why it is possible to see airplanes forming contrails as they pass through one region of the sky but not in another. It is also why planes travelling in the same direction passing over the same point can have differing degrees of contrail formation - atmospheric conditions can be very different at different altitudes.

Meteorologists began to study contrail formation during World War II when it became a matter of military importance. Since contrails were dangerous to high-altitude missions, giving away the locations and flight paths of Allied planes, the military was keen to understand why these clouds formed.

A National Weather Service meteorologist named Herbert Appleman created the Appleman Chart to forecast the conditions of temperature, pressure, and humidity that would be most likely to cause contrail formation. Well over a century later, we can still use this chart - in conjunction with atmospheric sounding data from weather balloons - to predict whether contrails will form over a given area at a given altitude.

Atmospheric conditions not only determine whether contrails form, but also how long they last and how they behave after formation.

Contrails that form under cool and dry atmospheric conditions will dissipate quickly.

Contrails that form under cool and dry atmospheric conditions will dissipate quickly.

When temperatures are very cold but the air is dry, contrails will persist longer without spreading.

When temperatures are very cold but the air is dry, contrails will persist longer without spreading.

Persistent spreading contrails form when there is more moisture in the upper atmosphere.

Persistent spreading contrails form when there is more moisture in the upper atmosphere.

Types of Contrails

High-altitude contrails can be generally categorized into three types. These types form depending on differing conditions of temperature and humidity at cruising altitude.

Short-lived contrails dissipate very quickly after formation, usually a few minutes. These form when humidity in the surrounding air is low and temperatures are warm - by upper-troposphere standards. The mix of exhaust and outside air just barely crosses the condensation curve, forming a contrail. As the mixture continues to cool, the ice crystals in the contrail pass the point of sublimation and begin changing phase back to gas, causing the contrail to dissipate.

Persistent contrails form when temperatures are much colder, allowing the ice crystals to remain in the upper troposphere for many minutes longer. As these contrails age, the ice crystals within them begin to sublimate back to gas, causing them to eventually disappear. However, these can remain for dozens of minutes to longer than an hour.

When persistent contrails form under high-humidity conditions, the ice crystals not only remain in the upper troposphere, but spread as the wind carries them, causing more ice crystals to form. These persistent spreading contrails can remain for many hours, mixing with other contrails to form an artificial cirrus aviaticus blanket over the area.

Are Airplanes Spraying Chemicals Into The Air?

It should come as no surprise that contrails have become the subject of an Internet-enabled conspiracy theory, since the Internet has provided the science-illiterate with a far-reaching platform for congregation. Proponents of the "chemtrail conspiracy" insist that persistent contrails are the result of chemicals being sprayed into the atmosphere by high-altitude top-secret aircraft. Exactly what is being sprayed is not known, of course, but proponents are certain that it is for nefarious purposes ranging from geoengineering to weather manipulation to mind control.

But is it true?

The simplest answer to this is "yes." The two main products of jet fuel combustion are carbon dioxide (about 70%) and water vapor (a bit under 30%). Other by-products such as carbon monoxide, sulfur oxides, nitrogen oxides, and soot are produced in far smaller amounts. All of these are chemicals, by definition. Therefore, airplanes are definitely spraying chemicals into the air via their exhaust.

Could there be airplanes on secret missions from secretive sources filing secretive flight plans and spraying additional secretive chemicals into the upper atmosphere? It's possible, but not likely. And there is currently no evidence to support such an assertion.

Geoengineering is by far the most plausible of the "chemtrail" conspiracists' ideas, and it is an idea that is still highly conceptual. Though there have been some proposed geoengineering schemes that would emit reflective nanoparticles into the stratosphere to reflect solar radiation and combat global warming, these are still hypothetical ideas and are not currently being tested.

Even if such geoengineering schemes were being conducted today, airline contrails would not be an effective method of distribution. In fact, they would be counter-productive. Persistent, spreading contrails have a net warming effect on the land area below them, reflecting heat energy back down to the ground. This is in addition to the carbon dioxide contributed to the atmosphere by the airplane's exhaust. Therefore, assertions that current airplane contrails are part of a geoengineering scheme are not based in fact.

Sources and Further Information


artblack01 from New Mexico on May 16, 2017:

Wendell, airplanes even ones that fly over us on a daily basis do not block out the sun with their contrails, the contrails are water vapor and not exhaust though there is some exhaust involved it's much less than the ones that come from cars, in fact the bigger the city the worse smog (smoke and fog) is... cars cause most of this, as well as factories, both are ground based. Second, if contrails were the cause of autism autism would be at epidemic levels, it's not, I know a couple autistic people and I have a friend who is aspergers autistic who has kids who are not autistic, in fact many of my friends who have kids only one of them was autistic.... all of them have had vaccines as well so there goes that theory...

Conspiracy theorists are a huge epidemic in the United States, it is the leading cause of people saying stupid things and causing a general panic and creating dumbass laws for no good reason in our nation, this increases the sickness we have in this nation which is getting worse to the point of epidemic levels. What is this sickness? Stupidity. What causes this terrible disease? Lack of education and an increase in misinformation. What is the leading cause of misinformation? Paranoid conspiracy theorists. You see, the biggest problem with conspiracy theories is that they lack any real scientific evidence and it's all based on fear and conjecture. Fear is created by ignorance.

IF you get an education, and I don't just mean from schools but from a general knowledge in actual science and the ability to yourself test and experiment and collect evidence, then you can fight and even ignore the misinformation caused by stupid conspiracy theories and misinformation purveyors.

Wendell on May 16, 2017:

People are actually buying into this Com trail scam. It's geo-engineering at it's worst. If the all day and all night long clouds covering hundreds of square miles of sky in the Summer months is just jet exhaust does that not raise a red flag?

I'm not a conspiracy theorist; I'm a Conspiracy Analyst and after analyzing this article I find it is complete and utter poppycock, contrails...indeed. Very sad.

If this exhaust is so bad as to actually block out Sun light does this not raise concern for agriculture?

When study after study on our municipal water systems show increasing spikes of aluminum, barium, etc.? Are you concerned whatsoever for the health of your children, who are experiencing a lot of cases of autism lately?

Are you aware of the Public Law passed which provides that the general public may be exposed to aerosols sprayed from planes without your express permission in the interests of science?

They could be putting fluoride in that stuff for all one is to know. Don't you people like what the Sun does for Humans?

somethgblue from Shelbyville, Tennessee on April 14, 2015:

See how easy it is, you simple can't resist responding, anything I say requires a response. This is the conditioning I talking about, your mind has been programmed to always get the last word to protect your fragile ego.

In essence I am doing your thinking for you by pushing the necessary buttons to trigger a response, that is mind control, pure and simple. TV works the same way, it constantly programs you to seek proof or evidence to accept anything as true.

Your dismissal should have been the end of this conversation but your conditioning overpowered your brain to protect the sanity of your ego.

artblack01 from New Mexico on April 14, 2015:

Ha ha, if that makes you feel better about being a delusional nut job, go right ahead and believe what you like.

somethgblue from Shelbyville, Tennessee on April 13, 2015:

Pushing your buttons is so easy a fifth grader could do it, let's face it Art I Own You. I can play you any time I wish however manipulating a person with the intellectual capabilities of a flea is hardly worth my supreme brilliance.

I merely find it amusing to idly provoke your childish responses like the conditioned sheep that you are. You cannot refrain from spouting, cursing and spewing your inane drivel anymore than Pavlov's dog could prevent drooling at that mouth, it is basically the same.

artblack01 from New Mexico on April 13, 2015:

You've never left your home and lived in the world and been to court or jail or any of that? Someday, maybe you'll learn. Until then, you are just a sheltered nut job with no sense of reality whatsoever $6, you are dismissed.

somethgblue from Shelbyville, Tennessee on April 12, 2015:

Tsk, Tsk kind of the pot calling the kettle black don't you think?

TV isn't realistic or believable in any stretch of the imagination, especially cop shows, that isn't even close to reality. It merely conditions the masses to feel the need for proof, for scientific evidence.

Science is conducted through observation and a collection of data often to back up a theory or concept. It is a collection of opinions, sometimes facts are used but often times these 'facts' change after more data is collected.

A well researched book with references, footnotes, appendix and bibliography allows the reader to review the material it was founded on and take their time doing it.

A TV shows is 30 to 60 minutes long and has none of these things just a talking head giving you the story they want you to accept.

College is a crock designed to put the student in debt, I just received another degree in 2011 and they are now teaching kids geography by differentiated countries by internet service, cell phones and indoor plumbing. Most text books are now published by the World Bank, colleges are about money $$$, nothing more, nothing less.

My High school education 35 years ago was better than any four year degree nowadays, because they have lowered the standards so low a baboon could graduate college, which explains why you think so much of college.

You got played and evidently you still are by your sad rhetoric.

Cuss words do indicate class, anybody can cuss, those with integrity don't require it . . . write an email to your Momma using that kind of language and see how that works for you.

artblack01 from New Mexico on April 12, 2015:

somethgblue, You misunderstand me, I don't use TV for anything, I am saying the lowest common denominator does which would be you. And Cuss words do not indicate class, your ability to talk to and relate to people indicates class, fuck "class", it indicates nothing about what is in a persons heart and soul and intelligence. What it does indicate is how much respect I have for YOU, NONE.

USE YOUR FUCKING BRAIN for once. Stop following what other people say is true and LOOK for yourself. Your book, by Jerry E. Smith, is no better than an unintelligent TV show.

My example for TV, since you love to straw man attack and ad hominem attack, was to show you that even those shows try to make the discovery of evidence realistic enough to make them believable. My science comes from when I went to college, it has nothing to do with TV for which I don't actually own one, I don't have time or money to care about such things.

But yeah, if you would rather attack the person than argue what they have to say, I think that show how much LESS CLASS you have than an uneducated hood rat.

somethgblue from Shelbyville, Tennessee on April 12, 2015:

Thanks for showing us your true class, intelligent folks do not require cuss words to express themselves.

The fact that you equate a TV show with scientific proof says it all. TV is so far removed from reality it is not even worth discussing.

TV is designed specifically to control weak minds and program the sheep, I will not be your Bo Peep, go back to the flock, Baa, Baa.

artblack01 from New Mexico on April 12, 2015:

"What is it you consider 'actual conclusive evidence'?"

Take a science class, any science class, learn even the simplest, like forensics or something, watch a fucking CSI or Law and Order or some kind of cop drama or criminal documentary to find this out. Look up what it takes to prove that something is true, what kind of evidence is necessary to make a claim a provable statement. Seriously, you are fucking clueless.

artblack01 from New Mexico on April 12, 2015:


You are a nut job,

First off, yes, conspiracies do exist. Conspiracies to do all sorts of things. But how do you convict someone of a conspiracy? You need evidence. In criminal law, a conspiracy is an agreement between two or more persons to commit a crime at some time in the future. What is evidence? The available body of facts or information indicating whether a belief or proposition is true or valid. An argument, whether it be from a book, or from the mouth of some people saying they saw something is NOT evidence. That is called hearsay if evidence is absent of this testimony.

"The absence of proof isn't, the proof of absence."

This statement may be true but it does NOT validate the paranoid delusions or beliefs of ANYONE if these people have ZERO evidence to back up their statements.

Yes there are planes that seed clouds in order to get them to precipitate in dry seasons so that it will rain and quench drought ridden areas, this isn't a conspiracy and the chemicals used are not harmful.

You have yet to provide any confirmable or verifyable.

You don't even have a logical argument for why these contrails are chemtrails, nor have you any evidence to even suggest that chemtrails exist for any purpose other than cloud seeding for rain which is done by specialized planes and crop dusting which is done by low flying planes, also specialized. I have yet to even see picture evidence that other planes are spraying "chemicals" of any kind over cities anywhere.

"The Truth Exists, Fiction is Created."

This chemtrail conspiracy is a fiction that was created by paranoid delusional people and propagated by moronic and paranoid delusional people, such as yourself.

The statements you have made does not confirm the existence of chemtrails, just continued to enforce our belief that you are a nut job.

You call us sheep, but you are the one believing such crap without evidence, without proof, just statements of paranoia made by other nut jobs. Sheep don't do research to prove or disprove the validity of something. But sheep, like YOU, will look for only statements that back up (not prove) the delusions they have.

For example, the sheep who believe in a God, I used to believe in a God, and I still would if I had not questioned whether or not a God existed. Since there was no evidence to prove that a God existed, and the statements made by religious texts contradicted the facts and evidence found by scientific inquiry into the nature of everything, I can only conclude that I cannot believe in a God until evidence is provided and I can only go by what the evidence shows.

Evidence for contrails exists, evidence for chemtrails does not.

If Chemtrails were so prevalent and if the Government was involved, trust me, I would have found it. And being someone who hold zero, none, absolutely no loyalty towards any nation or social authority, and always questions the agenda of all laws and actions taken by all members of any so called authority on ANYTHING, if chemtrails existed at all I would know.

The claimed reasons for "chemtrails" whether it be for controlling weather or population control, if you look at both logically and scientifically false and idiotic.

One, what machine spews more harmful chemicals than any other single machine on Earth? Cars, there are not enough chemical spraying planes on Earth to negate what cars do. The emissions from cars effects our atmosphere more than almost anything on the planet (with the exception of some factories and failed nuclear power plants).

The weather is effected mostly by the airstream and the air temperature and land formations and the ocean temperature and flow. If you can change that then you can change the weather.... spraying chemicals from airplane CAN NEVER CHANGE IT ENOUGH TO EFFECT OUR WEATHER. And it would be unnecessary if you could have chemicals do so.

The temperature of the Earth has been slowly climbing since the Industrial age occurred, it can only be fixed if you could negate the damage that we have been doing with toxic emissions since the Industrial age and the manufacture of automobiles.

The ONLY truly effective way to do this would be to either make all machines that produce toxic emissions clean. All other attempts to change the weather, if possible, would at this point actually be welcomed since the change in our weather, by human produced waste, is capable of causing the near extinction of most life on Earth (especially humans) in the near future.

"Since the beginning of this country our Government has been seeking ways to modify the weather using similar techniques, this is a fact."

This statement is complete bullshit because the Government has not had the knowledge that any technology was capable of doing such a thing. And the idea that humanity was capable of changing our world in such a drastic way was unheard of until fairly recently. Not even 100 years ago did ANYONE think such a thing was possible. And realistically, until humanity exceeds in our technological capabilities, is still not possible.

What you are spouting is beyond fiction, but science fiction.

Any yes, in the future, these things can ALL become a reality, but at the moment, it is not.

somethgblue from Shelbyville, Tennessee on April 11, 2015:

In his book Weather Warfare (which I own), Jerry E. Smith makes some good points that can't be disputed , that are facts. However they do not constitute proof or evidence, which as we both know can be contrived through faulty conclusions.

He says' that for anyone to 'know with certainty' that the chemtrail conspiracy is a myth, they would have to know what every aircraft all over the world is doing everyday and no one is that omniscient.

The absence of proof isn't, the proof of absence.

Our prisons are full of people that have been convicted of crimes that are labeled "Conspiracy to commit fraud, extortion, murder and so forth . . . ", so obviously Conspiracies exist and are proven in a court of law everyday.

The State of Oklahoma has been engaged in cloud seeding through the introduction of sprayed aerosols since 1996, known as OKWMDP. You can go to www.evac.ou.edu/okwmdp/ to verify this state run division of the Water Management Dept. exists.

Chemtrails exist, this is a fact. Contrails exist, this is a fact. However they are not the same and your article claims it is, which is a faulty conclusion based erroneous and misleading information.

However I do agree that the new High By-Pass Turbo Jet Engines have created and lead to more persistent contrails that are mistaken for chemtrials by those that have not researched the subject.

But to make the erroneous blanketed (excuse the pun couldn't resist) statement that chemtrails are in actuality persistent contrails misidentified, would be like saying all fish are trout. There simply NO WAY for you to know this.

Further more to make the statement that I have no way of knowing if I could grow bigger and better crops in my garden using chemicals stretches your credibility to the extreme, because I do know and have proven it to myself. I used to be a sheep, just like you but upon getting sober and finding that a clear mind leads to clear thinking, I have since modified what I accept as true.

For thousands of years humanity has noticed that big volcanic eruptions produce ash clouds that block out the sun and change not just the temperature but the weather itself. Since the beginning of this country our Government has been seeking ways to modify the weather using similar techniques, this is a fact.

The Truth Exists, Fiction is Created.

somethgblue from Shelbyville, Tennessee on April 10, 2015:

What is it you consider 'actual conclusive evidence'?

An article on the internet, some photos, eye-witness testimony . . . ?

What do you need?

scottcgruber (author) from USA on April 10, 2015:

Blue, I must take issue with your statement. I do think for myself, and I do actually listen to my heart and soul. It is my heart and souls that tells me that the chemtrail conspiracy theory is a hoax.

I have no evidence of this other than the fact that the theory has been around for twenty years without a single piece of evidence to support it. However, I'm willing to change my worldview if someone can provide actual conclusive evidence.

Insane Mundane from Earth on April 10, 2015:

@Somethgblue: The guy was still preaching about satanic nuttery among many other widespread conspiracy lunatic schemes in the past, so I'm not sure which point you are missing. Oh, I get it... LOL!

As for the clouding of the membrane, I think that is something you had encountered long ago. Maybe y'all rednecks misconstrue global pollution/climate change with more exciting things like conspiracy-based depopulation plans of utter asininity. Good grief, it is the year 2015. There are much better ways to make people sick & die in this world besides playing nefarious atmospheric games; duh! Either way, the chemtrail thingy obviously isn't working, as the planet's population has hit a record high when concerning humanoids. Hmm, maybe they will come up with something better, that way the conspiracy articles will be even more titillating on the web; ha!

scottcgruber (author) from USA on April 10, 2015:

FHFF- Thank you for the links, but none of those are proof of chemtrails, sorry. Ted Gunderson is just repeating claims he read on the Internet, and the Indigo Skyfold is most likely a prank played on Chemtrail believers. Neither of these provide any sort of documentation or other evidence to back up their assertions. That which can be asserted without evidence can be dismissed without evidence.

The video of Rosalind Peterson is the closest to having some actual truth in it, but she never talks about chemtrails. She talks about persistent contrails and she talks about barium tracers used in ionospheric research experiments, but never touches on the actual chemtrail conspiracy.

As for your claim of having talked to "actual chemtrail pilots," I simply don't believe you. Like every other chemtrail hoaxer on the Internet, you are making a claim and providing no evidence to back it up. If you can back up your claim with evidence, I'll consider it. Otherwise, I have no choice but to conclude that you're lying.

somethgblue from Shelbyville, Tennessee on April 10, 2015:

Of course you know that to reinforce any idea, concept or theory you can just fake photos that any insane clown then can use as proof to say see we have had them back in the day even before I grew a brain.

The whole point that you seem to miss living up yonder in the holler, is Felon lives in the Sunshine State, that ain't the Sunshine State no more. We had our first clear day of complete sunshine the other day in Tennessee and it took THREE months to get it.

When I first moved here 10 years ago, the attraction for me was the great sunny weather and now it rains and is overcast ALL THE TIME, get clue clown-boy the chemicals have destroyed the membrane.

Insane Mundane from Earth on April 10, 2015:

I just checked out that first link from the Former FBI Special Agent. Dang, that Ted Gunderson sounds like a real screwball - especially after reading pages like this:


Yeah, FHFF, I doubt if most people would even consider that as a source of proof, nor would I in this particular case.

I remember seeing these lingering contrails before this conspiracy theory propagated on the Internet, and it was quite normal back then. Well, I guess it was because we didn't have public Internet when I was a kid. Anyway, while quickly browsing through the InterWebs, I just found a page showing persistent contrails from decades ago, for the ones that deny that such common things existed in the past: http://contrailscience.com/contrail-photos-through...

It is an entertaining subject regardless if a tin-foil hat is required or not; ha!

somethgblue from Shelbyville, Tennessee on April 10, 2015:

FHFF, there is no chance of forcing Scott to see the truth, he has turned away from his heart and soul and prefers to allow the thinking of others to soothe his ego.

I have tried for many years, to the point that I suspect he is being paid to share these clearly propagandized ideas and concepts as way of reinforcing the conditioned dogma of the Powers That Were.

I too have grown up on AF Bases all over the World and 'know' the difference between a 'persistent contrail' and a chemtrail but these folks are simply in denial . . . so what is one to do?

The Truth Stands Alone and needs no defense, all will be revealed in time.

FreeHelpForFelons on April 10, 2015:

Since my integrity is in question due to my past here is something else that may help a video from a former FBI Agent and the UN. No offense man but where have you been kids in Florida know about this stuff this is not classified stuff . Millions upon millions of Americans in the military already know about this stuff.

Former FBI Special Agent


UN Committee on Chemtrails And Geoengineering


Pilots of Chemtrail Flight Reveal All - FOR UNBELIEVERS !!!!!


100% Proof of man made chemicals in check the link above read the book not just one page read it look at the chemicals in the U.S Air Force Chem Trail Chemistry Handbook That is What We Are Breathing . Really You Thought That Was Condensation We Are Breathing.

If you think you have seen chemtrails head to Florida its unreal they can block the sun and blanket an entire city overnight.

This is the best I can share like I said I grew up on a us military base I have watched thousands of flights contrails dissipate quickly they do not form clouds for along time even at high altitudes.

Please stop listening to fox news these people will have you believing their is no such thing as global warming.

God Bless

FreeHelpForFelons on April 10, 2015:

The link I shared about the U. S Air Force Chem Trails Chemistry Handbook is the best I could do. I apologize if I offended you I understand the military also has people making blogs also. I grew up on military bases seen literally thousands of flights in my life I know what a contrail is and the difference between a chem trail. While I am a felon like you said that was along time ago. I have studied this issue and have even comtemplated doing a In forma pauperis to fight to the highest courts but the people love chemtrails so why stop it. I have my opinions what should be done to stop it but I leave it in the hands of god. What I share is real . I have personally talked with air force pilots and they admit they feel bad for spraying this stuff but hey when your paid to stand for dignity you have to do what you have to do..

scottcgruber (author) from USA on April 10, 2015:

No, proof is not in the heart. That is exactly what proof is not. You are confusing emotion and gut feelings for proof.

Even your example of your garden is not proof. It is an anecdote. The fact that you can grow a nice garden without "chemicals" does not rule out that you could grow a nicer garden with "chemicals." Since you have no control, you're not actually proving anything. You're just making an assertion based on one observation.

That may be "evidence" for you, but it is not evidence to those of us who live in reality.

scottcgruber (author) from USA on April 10, 2015:

Thank you for those completely irrelevant links, Felons. Interesting reading, though neither of them were actually evidence that planes are spraying aluminum nanoparticles at 30,000 feet. One was a basic chemistry textbook, without a single mention of airborne dispersal techniques. The other discussed the health effects of aluminum particulates and then leaped to the conclusion that these particulates were being sprayed from airplanes.

Assumption is not evidence. Geoengineering Watch, like other sites promoting the chemtrail hoax, starts from the assumption that the only way elements like aluminum and barium and strontium can get into the air is to spray them from airplanes. This ignores all of the other natural and artificial sources that put these elements into the air- dust storms, ocean evaporation, vehicle exhaust, industrial emissions, and so on.

It's also important to realize that aluminum is the third most common element in the Earth's crust. It is everywhere - in rock, soil, water, and air. It should not be a surprise when people find aluminum in rainwater and snow. We should expect to find aluminum there, along with silicon and iron and calcium and barium and strontium and other elements we find in rocks.

In order to prove that airplanes are emitting trails of toxic nanoparticles, you actually have to go up in a research plane and take samples. No chemtrail "researcher" has ever done this, despite these fact that such research planes are available for lease from several universities. You could raise the money through crowdfunding - I and many other skeptics would gladly contribute to an experiment that would prove once and for all whether or not chemtrails exist. So do it.

somethgblue from Shelbyville, Tennessee on April 10, 2015:

Again Scott what constitutes proof, a document on the internet?

I have grown a garden every year for the last twenty and never used pesticides, weed killer or any other chemical agent and every year people always comment on how big and rich my plants are, what is my secret?

I always tell them I put the love of my heart into my work and nurture the plants. This is the proof or evidence for me that we don't need to poison the Earth with chemical agents to produce crops.

Proof is in your heart, LOVE is the most powerful force in the Universe.

I can't change what is in your heart but I pray one day you will open it up and learn the truth.

FreeHelpForFelons on April 10, 2015:

I lived in a place in Florida where I hardly saw the sun in the wintertime. The place was bombarded with chem trails sometimes it looked like fog since it would come down at night. I witnessed from Pensacola Beach ,Florida ships shooting rockets also which created chem trails and . From my medical studies aluminum when breathed in after long term exposure can cause dementia , mental problems ,it can LOWER THE IMMUNE SYSTEM so it will greatly benefit the pharmaceuticals companys and doctors this enriches the rich and continues to leave the poor even poorer. What I do fear for the people is the our government is legally allowed to conduct experiments on the us population through the use of chemical agents only god know what can be released by those in charge of these chemicals. While I hope the people of earth try to stop this their not much the people can do with out the arrest of those in charge of these operations along with the closure of all groups of societies with links to these activities.

Here is the proof you wanted .

U. S Air Force Chem Trails Chemistry Handbook.



somethgblue from Shelbyville, Tennessee on April 09, 2015:

Yes, I got tons of evidence, more evidence than you can shake a stick at, proof, my computer is just filled with proof. All you have to do is Google it and the evidence and proof just pops up on your screen, it like magic.

What would you do with evidence Scott? You wouldn't recognize it if it barfed in your lap, your so-called science tells you want to think and just like Pavlov's dog you lap it up, then regurgitate it into articles like this.

What boggles my mind is Googles' lap dog, HP endorses it.

Insane Mundane from Earth on April 09, 2015:

Some of these comments are hilarious. I don't think we need chemtrails for aluminum contamination and/or minuscule, air-borne particulates of such a beloved metal. Good grief... [Sigh] Many of the over-the-counter medications, common antiperspirants, cookware, and a seemingly endless supply of food products contain more aluminum than the average Joe would even want to realize.

Aluminum doesn't seem to be readily absorbed in the body (definitely not when orally consuming such things), and a lot of it just passes through your intestines without entering your bloodstream albeit this redundant metallic scare is great news for the ones trying to sell those trendy "Aluminum Testing Kits." LOL!

scottcgruber (author) from USA on April 09, 2015:


Thanks for that interesting comment. Got any evidence that demonstrates that these aluminum particulates are being released from airplanes as opposed to pollution from transportation or industry?

FreeHelpForFelons on April 09, 2015:

The aluminum particulate when breathed in is harmful to the thyroid could possibly be linked the the high rates or breast cancer in America emerging all of a sudden these past two decades. Alimunium can cause mental problems and a lot of health issues.

It is my personal belief that chem trails are used for weather modification , shielding. possible links to mind control projects , population reduction since the elite are not capable of creating a more equal world where people can live in a state of equality in return this creates megalomaniacs that think they have to take it upon themselves to reduce the population when the entire population of earth can fit in New York City . The notion that to many people exist is absurb . It will take a lot of money and support to tackle these terrorist on an international level assinations are key but at this moment the human population has not reached this level of self respect . I just hope they do for the sake of the people and mother nature. It will take a tremendous amount of coordination and a few thousands people to dispose of the trash efficiently and effectively hopefulyl it will be done on a international level till then the people will be powerless to terrorism

scottcgruber (author) from USA on April 08, 2015:

Somethgblue - my apologies. You wrote some good questions here several weeks ago and I have not yet responded. I'll try to clear up some confusion.

Regarding high-bypass vs low-bypass engines, the issue is not whether they create "more" or "fewer" contrails. They create persistent contrails over a range of temperatures and pressures that are slightly different from the range of temperatures and pressures at which low-bypass engines create contrails.

The Appleman chart provided above illustrates this - it provides a model of when we should expect to see contrails and when we shouldn't. On the left side of that temperature/pressure curve, contrails form. On the right side, we don't.

When Herb Appleman figured out this formula in the 1950s, it was based on older turboprop and low-bypass jet engines. High-bypass jet engines, as Ulrich Schumann found, obey a slightly different curve. They produce contrails under temperature and pressure conditions that would be plotted a little bit to the right of the Appleman curve, slightly warmer or slightly lower pressure.

This doesn't mean that low-bypass engines never produced contrails. They obviously did. It means that the border between atmospheric conditions when contrails are or aren't produced varies depending on the engine.

As for your example - an airplane flying at 10,000 feet is very unlikely to produce contrails, as the temperature will not be low enough. Temperatures need to be below -40 degrees Celsius, which you don't generally find below 20,000 feet except in very extreme conditions - perhaps Antarctica or Siberia in the coldest part of the winter. You're almost certainly not going to find these conditions at ground level. So your hypothetical of a plane creating persistent contrails during landing is not realistic.

Airplanes do occasionally create aerodynamic contrails on takeoff and landing - these form from vortices on the wingtips and horizontal stabilizers, generally. These are not persistent, however - they usually dissipate quickly.

Hope this clears up any confusion.

scottcgruber (author) from USA on April 08, 2015:

Thanks all for the new follows and comments - I'm glad you enjoyed this article!

Science not Science: You bring up an interesting point. True, I didn't go into weather warfare in this article. This is because I was focusing on reality for this article rather than speculative fiction. "Weather weapons" would certainly be an interesting topic and you are more than welcome to write on it yourself, but it was far outside the scope of my article on contrails.

Your comment about the "poor timing" of this article is also quite interesting, particularly since the article is over two years old. Nevertheless, I think this is indeed a perfect time for a science-based article such as this. We live in a time when science is under constant attack - from vaccine deniers to GMO fearmongers to creationists to homeopathic snake-oil peddlers to governors who forbid their staff from even using the term "climate change." The Internet has allowed ridiculous conspiracy theories such as Chemtrails and Nibiru and HAARP to proliferate rapidly. My article is a small attempt to combat these forces of irrationality.

somethgblue from Shelbyville, Tennessee on April 08, 2015:

OH, contraire SnS, read the comments we have tried in vain to show our disdain for this mockery of science but when HP gives credence to this sham by naming it Hub of the Day all you can do is shake your head in despair and laugh.

Science not Science on April 08, 2015:

Excellent disposition on the subject of condensation. Which leaves the subject of weather weapons totally unexplored. It's a pity there is no addressing citizens concerns and the poor timing of this article only encourages blind mockery.

Venkatachari M from Hyderabad, India on April 05, 2015:

It is very interesting to learn about these contrails. WE know that planes leave gases that trail for sometime even after the plane disappears. It is just like we observe the smoke trails behind our vehicles when they are not properly checked for pollution control. We see the smoke even after the vehicle passed a long distance. These things are harmful to mankind causing polluted air supply to us and heating up the environment.

Very good topic reviewed by you elaborately. Thanks for sharing it. Voted up and interesting.

Susan Deppner from Arkansas USA on April 05, 2015:

What a thorough explanation of contrails! Very interesting and informative. Congratulations on HOTD today!

Kristen Howe from Northeast Ohio on April 05, 2015:

Congrats on the HOTD today, Scott. I always wondered about contrails. What a real informative and interesting hub. Voted up for awesome!

DW Davis from Eastern NC on April 05, 2015:

Living near an active Air Force Base we see plenty of contrails in the skies over our town. When I taught science and we covered weather and cloud formation, I would take the students outside on a clear day and show them the contrails and explain how they were similar to and how hey differed from natural clouds. Were I to teach on that subject again, I would be glad to use your Hub as a source.

Susie Lehto from Minnesota on April 05, 2015:

Thank you for the educational information about contrails.

Congratulations on HotD!

Eugene Brennan from Ireland on April 05, 2015:

Congratulations on Hub of the Day and spreading science fact rather than conspiracy theory nonsense!

Voted up and shared!

somethgblue from Shelbyville, Tennessee on February 15, 2015:

Yes, I am.

artblack01 from New Mexico on February 15, 2015:

You are so entertaining.

somethgblue from Shelbyville, Tennessee on February 14, 2015:

You're are so right, how did I ever make it through life without you to point out the obvious . . . unless you're just in love with your own written words and feel the need to prattle on and on and on.

artblack01 from New Mexico on February 14, 2015:

When you are ignorant of science, and a complete paranoid conspiracy theory believing nut job, nothing makes sense except conspiracy theories even if there is no science, facts or evidence to support them.

somethgblue from Shelbyville, Tennessee on February 13, 2015:

Scott, upon further review I now get the concept that High By-Pass Turbofans can and do create persistent contrails from actually creating cleaner exhaust, I get it.

The couple questions I have, and hopefully you can clear it up for me, is obviously these PCs are diminishing the strength of the Sun as it is blocking the rays from reaching the surface, that sucks, I like sunny days. Don't you see this as a problem?

I still don't by into the pattern they create in the sky, the cross hatch and the circles and random patterns and I can show you hundreds of photos showing this, so there is no point in denying that.

But the other question is if these persistent contrails are basically more prevalent than ever due to the HBPT jet engines, the lower by-pass engines wouldn't have produced contrails as is shown in the photo we talked about earlier, if so why use the argument that they were prevalent in the past but not recognizable due to less traffic, it doesn't make sense?

You can't have it both ways or are you saying that the new technology created not only the same results but more of it?

Furthermore if the temperature at 10,000 feet is say, zero degrees, which creates persistent contrails and a plane comes into a landing say in Minnesota and the ground temp. is zero it should be producing persistent contrails the whole way but we don't see airliners around airports spewing these huge plumes, it doesn't make any sense.

If you use the argument of temperature, then in the winter from take off to landing they should be spewing persistent contrails and we don't see that?

clear this up because it is not making any sense . . . ?!

Insane Mundane from Earth on February 10, 2015:

Sparkster, you read into an earlier comment wrong. When I said, "The only conspiracy that I see, has to do with the global warming debates, ice caps and atmospheric remedies." I was talking about within this asinine chemtrail debate. The only possible "conspiracies" involving chemtrails would most likely involve those scenarios and not the "dropping stupid gas on society" nonsense.

Marc Hubs from United Kingdom on February 09, 2015:

Yet you only "assume" there are "chemtrail" experiments happening which have nothing to do with the purported sinister conspiracy theories?? Duh!! So what conspiracy can you see relating to the global warming debate?

Insane Mundane from Earth on February 09, 2015:

Sparkster: Duh! I was doing research on Global Warming when I was in my 6th grade advanced science class. Why are you telling me that climate change is happening? LMAO!

Marc Hubs from United Kingdom on February 09, 2015:

Insane Mundane, there's no doubt that global warming (or climate change) is really happening. Since the industrial revolution we have emitted half a trillion tonnes of carbon dioxide into the atmosphere. Obviously, before the industrial revolution we didn't have all this pollution. That's another reason for stratospheric sulfate aerosols, in addition to solar radiation management. According the Council On Foreign Relations "one kilogram of well placed sulfur in the stratosphere would roughly offset the warming effect of several hundred thousand kilograms of carbon dioxide". Of course, the spraying of such aerosols could easily be used to secretly carry out bio-chemical warfare.

Insane Mundane from Earth on February 09, 2015:

In other words, don't freakin' be like the Dale character from the animated sitcom known as "King of Hill."

...But then again, he did breathe in way too many insecticides during his fictitious lifetime. Ha-ha!

artblack01 from New Mexico on February 09, 2015:

If you are not sure if a plane is commercial or not I have a website for you.


As far as everything else, ignorance for something can often create fear, fear of the unknown is the most intense fear one can have which is why many of these conspiracy theories seem to hold so much weight is due to the fact the many people are ignorant to reality, many people listen to those that would exploit the ignorance of others for "entertainment" and fame e.g. Alex Jones and other mass media outlets that only tell you things that give them great ratings and therefore more money.

In our nation, ignorance is bliss, paranoia is money.

There are many real dangers in our society, with our government, in our world.... and the best way to keep a population down is to keep them ignorant... take for example, vaccines, if you want population control then make people scared to get vaccines because people believe they cause autism.... but if you know anything about autism you'd know not getting vaccines can kill people and people who have autism are often far smarter than everyone else, savants. So believing in stupid conspiracies can be more harmful to humanity than doing research and finding EVIDENCE on the validity of both sides.

somethgblue from Shelbyville, Tennessee on February 09, 2015:

You almost have me convinced but the problems I have that leaves a nagging doubt is, that I have looked at some of the planes that have these huge PCs (persistent contrails) behind them through my telescope (mostly my binoculars) and they don't have logos of commercial airliners on them and don't look like commercial aircraft (close but not quite), plus although they're flying at level altitudes, the altitudes are much lower than CA's (Commercial Aircraft) fly when they are at cruising altitude.

When I see PC's being formed it is at 10 to 20 thousand feet, not 30, and we both know the temp isn't -40, so that is really what has me wondering, these PC's form from craft that are too low.

CA's , at cruising altitude is much higher and don't leave PC's behind them. Then you see these photos of the insides of CA's with tanks of whatever in them and no seats and it makes you wonder.

If PC's, as you mentioned, are causing problems with our atmosphere in terms of Sun Dimming, air pollution and other factors, then surely we should try to cut down on them, such as we have with car pollution and yet we seem to have more of them, from increased traffic.

Then you throw in the Geoengineering debate which there is a lot of disinformation about, denial and even censorship and it makes me wonder why would they try to cover up something that is supposed to be helping with climate change and global warming.

I fully admit you maybe right about this and I maybe wrong but something is fishy and I just haven't figured it out . . . yet! However you have given me plenty of ideas, concept and information to look into and analyze, I appreciate it, thank you.

scottcgruber (author) from USA on February 09, 2015:

Planes that are on approach to or departure from an airport will not leave contrails because they are too low and the air temperature is too warm. Contrails form at temperatures below -40, which usually occur at around 30,000 feet.

Shelbyville, Tennessee is close to a main flight route from northern cities like Chicago and Grand Forks to Atlanta and Orlando, as well as from mid-Atlantic cities to Texas. These flights crisscross at cruising altitude at almost a perfect right angle. This would easily explain why you see a crisscross pattern of contrails where you live. It's not Nashville air traffic, it's flyover air traffic.

somethgblue from Shelbyville, Tennessee on February 09, 2015:

No, really I didn't see any in the 60s, 70s and 80s, because there weren't any. These just started happening around the time global warming became an issue.

I live right next to a busy airport and know which direction the flight paths of commercial airliners take. Yes some are North & South and some are East and West but these planes do not leave any persistent contrails behind them, ever.

The chemtrails I see do not follow these flight paths, they take irregular flight paths that aren't in the direction of any major cities or destinations.

So why the need to predict contrails, because they impact the climate, such as changing the weather, create global warming and climate change, hmmm!

scottcgruber (author) from USA on February 09, 2015:

"However if chemtrails are really just persistent contrails why do they not follow the flight paths of commercial airliners. Why do they criss-cross all over the sky, where are these commercial jets going where they need to make irregular flight paths and curve back on themselves? Why do our skies look like checkerboards at times?"

They do follow the paths of commercial air traffic. Some planes go along north-south routes. Others go along east-west routes. Where these routes intersect you get a checkerboard. It isn't one plane turning around and making multiple passes.

As for why Schumann was trying to prove that high-bypass planes leave contrails - he wasn't. If you read the studies I linked, you'll see that he explains the context - trying to better understand the conditions under which controls form to help predict the impact of contrails on the climate, since they have a net warming effect. The Appleman chart, which I have included in this article, does a pretty good job of predicting when contrails form but it isn't perfect - Schumann noticed that contrails were forming under conditions that didn't quite match the chart's predictions. He hypothesized that the bypass ratio of the engine played a role, the tested the hypothesis mathematically and then through experiment.

As for your assertion that you never saw persistent contrails in the 60s and 70s, it is simply untrue. You didn't see as many of them because there were fewer flights at the time, but you saw them. You just didn't notice because there weren't ridiculous internet conspiracy theories back then.

somethgblue from Shelbyville, Tennessee on February 09, 2015:

I guess, I'm wondering why a scientist like Ulrich Schumann would spend so much time and research trying to prove something was true such as High By-Pass Turbofan Jet Engines produce contrails that last for hours in 2001, is there a need for proving things are true?

Why does the science of Geoengineering and especially SRM (Solar Radiation Management) have the technology that exactly mimics the production of the so-called chentrails and then go to such great lengths to cover up that this technology does in fact exist.

Why not just come out and say, yes we are messing with the weather and the atmosphere but it is for everyone own good, why try to hide it?

Something doesn't seem right about that, you only cover up something you want to hide.

somethgblue from Shelbyville, Tennessee on February 09, 2015:

So you think these extremely long, thick plumes that criss-cross the sky on a daily basis are just persistent contrails?

Insane Mundane from Earth on February 08, 2015:

I already assume there are actual atmospheric experiments involving "chemtrails," which has nothing to do with the reasons provided by the propagated conspiracy theories of the chemtrail conspiracy theorist nutjobs out there. Dropping massive clouds of stupid gas while poisoning the planet via these blindly executed chemtrails just doesn't fly, in my book.

However, there is no doubt that certain chemtrails are real, as crop dusting, skywriting, cloud seeding or the act of spreading flame retardants (which is widely known in California, for example) and water down for forest fires, is all wildly and widely accepted by the masses. The only conspiracy that I see, has to do with the global warming debates, ice caps and atmospheric remedies. *Sigh*

Marc Hubs from United Kingdom on February 08, 2015:

Another logical question would be why are the GAO and IPCC admitting to currently spraying reflective aerosols in the atmosphere if they're not really doing it?

somethgblue from Shelbyville, Tennessee on February 08, 2015:

You're right Scott, they should have different engines, I sit corrected.

However if chemtrails are really just persistent contrails why do they not follow the flight paths of commercial airliners. Why do they criss-cross all over the sky, where are these commercial jets going where they need to make irregular flight paths and curve back on themselves? Why do our skies look like checkerboards at times?

If Geoengineering doesn't exist because chemtrails doesn't exist, why are there companies that use that title in their names? Why are there phrases like Stratospheric Aerosol Geoengineering (SAG) and Solar Radiation Management (SRM) to describe technologies, science and programs that don't exist?

Why did the Super Powers sign a treaty in 1975 declaring weather weapons can't be used in times of war if weather weapons don't exist?

Why is there such a huge cover up and complete silence, censorship and disinformation if these programs don't exist and aren't real, treat it as fantasy and move on.

Are you really saying that the new High By-Pass Turbofan Jet Engines create massive condensation trails that cover the sky for the whole day, when inferior technology of the 50s, 60s and 70s produced nothing?

Remember I grew up on AF Bases all over the world in the 60s and 70s and saw none of these contrails covering the sky from horizon to horizon, why all of sudden are they appearing.

In the last ten years the weather in TN has changed from being very humid, sticky and hot to almost Colorado like weather, with very low humidity and cool yet our skies are criss-crossed with the persistent contrails that last all day, that don't follow the flight path of the airliners, how can that Be?

somethgblue from Shelbyville, Tennessee on February 08, 2015:

It's AS, I said, retard, not 'like'. When you learn to write the English language correctly maybe I will take you seriously, until then I will just consider you the slow witted, brain dead, wannabe dolt that you show in your comments.

artblack01 from New Mexico on February 08, 2015:

Like I said, total nut job.

somethgblue from Shelbyville, Tennessee on February 07, 2015:

Or Clint, they're simply not human and are terra forming the Earth to suit their needs and having been living underground until the technology became available to recreate the Earth how they need it.

Consider you are a group of Aliens with superior knowledge and technology but are too few to take control, you live underground because you can't exist in our environment but use humans for food, especially kids, 'cuz they taste better (missing children). You use the Cabal/Illuminati/Royal Families to serve your evil purposes of sacrificing their own subjects in exchange for power, wealth and privilege. When you are ready you terra form the Planet Earth, so that you can live on the surface.

Think of Chentrails as humacide, just like wiping out insignificant insects, of course you keep enough around to serve as slave and cattle or food but wiping and diping the rest is no big deal.

I'm sorry, Scott were you trying to get my attention?

scottcgruber (author) from USA on February 07, 2015:

"We both know that both ascent and descent creates vacuum around the aircraft which will invariable cause contrails however during the level flight the Boeing aircraft does not form any contrails, as the photo shows. For the experiment to have any value both planes should be using the same engines, according to the article they're not, why?"

The 707 had four JT3D-J3 engines with a bypass ratio of 1.4. The A340 had four CFM56-5C4 engines with a bypass ratio of 6.8. This is clearly stated in the article I linked, in the paragraph right after the one you quoted.

I'm not sure why you think an experiment to demonstrate that contrail formation depends on the bypass ratio of the engine would be best if the engines were all the same. The whole point was to demonstrate that different engines create contrails under different conditions.

The ascent and descent were important because this allowed the experimenters to test the range of temperature and pressure over which both planes would form contrails, since these change with altitude. Even if the "vacuum" around the aircraft had a role in contrail formation (which it doesn't because it doesn't exist) this would be irrelevant to the results, since both planes and the research plane taking measurements would be experiencing the same "vacuum" conditions.

Face it, blue- you've been caught in a lie. You made a demonstrably false claim. I proved it wrong. The fact that you're retreating to "evidence is for suckers" is proof of this.

You're right about one thing- chemtrails are not contrails. Unlike chemtrails, contrails exist.

Insane Mundane from Earth on February 07, 2015:

Don't feel blue, Somethgblue. They also basically called Einstein, Benjamin Franklin, and a whole boatload of other people "nutbags" before their discoveries ever permeated the public, back in the day. However, I must say, I'm not really jiving with this chemtrail conspiracy thingy.

It is too stupid, even for the majority of humanity, to constantly spray their own people from high altitudes while ALSO living on the same surface. I mean, poison the food and drink, and they can avoid it. But to deliberately poison the air and soil in such a widespread fashion, makes no sense whatsoever. That is, unless all the Powers That Be are all dwelling in an underground cave somewhere during the last several decades. Blah!

somethgblue from Shelbyville, Tennessee on February 07, 2015:

Wouldn't that be if the Flux-Capacitor is a real device, after all what if time travel really works and the FC is the key to it all.

I'd rather be stuck in a delusional fantasy than exist as a mindless dolt with no clue.

Insane Mundane from Earth on February 07, 2015:

These debates are amusing... Just to change it up a bit, maybe one of y'all should feature an article covering the exhaust that's a bit closer to the ground, like the "catalytic converter conspiracy." Ha-ha!

artblack01 from New Mexico on February 07, 2015:

Blue doesn't believe in reality, he is stuck in his paranoid delusional fantasy world and is upset that we won't believe him and know that he is a nut job. "evidence and proof is for SUCKERS unwilling or unable to think for themselves" is a statement that proves this.

somethgblue from Shelbyville, Tennessee on February 07, 2015:

I don't need evidence, we have been over this before, evidence and proof is for SUCKERS unwilling or unable to think for themselves. I do not feel the need to provide evidence nor do I require it from you or anyone else.

I read the paper and found the article myself, it didn't change my thinking nor did it provide any information I didn't already know but thanks for trying, albeit a day late and a dollar short.

The paper itself didn't mention what engines were even used (although the photo does, interesting don't you think) during the experiments, however and I quote "For a direct test, a formation flight of two different large jet air- craft was arranged, wing by wing, during an ASCENT and a DESCENT of the aircraft."

We both know that both ascent and descent creates vacuum around the aircraft which will invariable cause contrails however during the level flight the Boeing aircraft does not form any contrails, as the photo shows. For the experiment to have any value both planes should be using the same engines, according to the article they're not, why?

Because the article itself is disinformation designed to give folks that require 'scientific' evidence, links to hang their hat on. I can make up my own mind and I'm telling you contrails are not chemtrails, period end of story.

scottcgruber (author) from USA on February 07, 2015:


Links to chemtrail hoaxer sites like geoengineering watch are not evidence. These sites don't present actual evidence of current geoengineering. They cite geoengineering patents, photos of contrails, and tests of rainwater, and assume that these are all connected. They do not provide conclusive evidence that geoengineering is happening now, nor conclusive evidence that the contrails in their photos contain anything other than water. This is not evidence in any sense of the word.

The papers I cited ( http://citeseerx.ist.psu.edu/viewdoc/download?doi=... and http://elib.dlr.de/9247/1/aerscitech-2000.pdf ) are ample evidence that high-bypass engines produce contrails, and even contained a photo of a plane with high-bypass engines producing contrails. What further evidence do you need?

somethgblue from Shelbyville, Tennessee on February 07, 2015:

Obviously, as I subscribe to the concept that chemtrails are fundamentally different from contrails, so why belabor the point that we disagree, that is pointless.

That being said I have provided ample evidence, which you chose to ignore, that is your right. If you prefer to wallow in ignorance that is your choice, no one is disputing your right to remain deceived.

Even the Government run website Wikipedia recognizes that Geo-Engineering exists. Here is a link in case your Google or Bing is broken.


Examples of their theoretical geoengineering techniques include solar radiation management, which they call stratospheric sulfate aerosols, while the rest of the world calls, chemtrails.

Even Scott, provided a title to a paper based on theoretical science, which I tracked down, as he conveniently didn't provide a link, and read. The paper is not very convincing but did provide some interesting disinformation and propaganda for the contrail theory, that I found amusing.

You on the other hand provide nothing but lame, inane drivel, disguised as insults and troll like rhetoric designed to inflame the subject while adding to boost your obvious insecure intellect. I pity your pathetic attempts at intellectual discourse however sincere they may be.

artblack01 from New Mexico on February 07, 2015:

So, tell me, what is the difference between theory and hypothesis? Do you know what the term cherry picking refers to? And why have you still provided zero evidence? No matter what evidence gets presented to you, you continue to deny that chemtrails are the product of paranoid conspiracy nut job's imaginations.

somethgblue from Shelbyville, Tennessee on February 06, 2015:

I did manage to find the article Influence of propulsion efficiency on contrail formation by Ulrich Schumann but am still not convinced, based on the fact that his model is a theory with varying experimental results to back it up.

For instance, the introduction to the paper had this to say about the theory and information and I quote . . .

" The statements were highly debated during the final acceptance procedure of the report and not all critics could be convinced that they are correct. Therefore this paper explains the basic thermodynamic arguments behind these statements and reports on recent experiments which support the theory."

In other words Ulrich comes up with a theory and then goes out and uses experiments to support his theory however even some of his experiments such as Aero Bus and the 747 flying wing tip to wing tip dispute his claims as the Russia aircraft produced contrails while the Boeing 747 didn't while flying at the same altitude.

I downloaded the PDF article for future use but I must say it isn't very convincing, got anything else?

scottcgruber (author) from USA on February 06, 2015:

The idea that high-bypass turbofan jet engines don't produce contrails is a frequent talking point in Chemtrail hoaxer circles. It is also completely false. In fact, high-bypass turbofan jet engines are more likely to produce contrails.

I can't post a link at the moment, but please look up a study published by Ulrich Schumann in Aerospace Science and Technology in 2000: Influence of Propulsion Efficiency on Contrail Formation. His research found that high bypass engines created contrails over a much greater range of temperatures than low-bypass ones.

In a related study published the same year, Schumann and his colleagues flew a research plane behind a Boeing 707 with low-bypass engines and an Airbus A340 with high-bypass engines - both planes flying in formation wing-to-wing. Though both planes were passing through the same atmospheric conditions at the same time, at many times during the test flight the A340 produced contrails while the 707 didn't.

This research and research by many other atmospheric scientists proves that the Chemtrail hoaxer talking point is false. High-bypass engines do produce contrails, and more of them.

somethgblue from Shelbyville, Tennessee on February 06, 2015:

The spokesperson for Captain Cut'n'Paste speaks, and of course uses attempted insults when facts aren't available to spread revisionist history and disinformation.

High By-Pass Turbofan Jet Engines DO NOT produce contrails, period end of story. I've given links and scientific facts, which you seem to require and yet when I do all I get is insults . . . exactly whom is the moronic nut job?

artblack01 from New Mexico on February 06, 2015:

somethgblue, you are such a moronic nut job. You really need to do your research so much better rather than relying on confirmation bias.

somethgblue from Shelbyville, Tennessee on February 05, 2015:

Of course what you left out is that all commercial airliners and military jets (since the late 80s) use High By-Pass Turbofan Jet Engines which by their very design DOES NOT produce contrails.

We both know why these engines not only cut down on fuel consumption and noise but make it virtually impossible to create contrails, so I won't bore you with the details but if you prefer your science from Government run websites you can read about why here.


Since 90% of the air doesn't even pass through the jet engine but the Turbofan, very little combustion takes place, hence very little exhaust and no contrails. So pretending that chemtrails are contrails is not only very unscientific but most unbecoming of a so-called intellectual.

For a deeper look at the contrail vs chemtrail myth, I can give you this website but this is more for your deluded readers than for you.


This article clearly demonstrates you are not interested in informing your readers but in fact to spread disinformation, as HBP Turbofan Jet Engines don't even produce contrails, they're a product of the past.

Jim Miller from Wichita Falls, Texas on March 09, 2013:

Oh, the conspiracy theorists are gonna get you for this one!

scottcgruber (author) from USA on February 23, 2013:

Thank you very much! As you may have guessed, this hub was inspired by a run-in with some chemtrail conspiracists. It's amazing how many "conspiracies" can be resolved just by learning a little basic physics.

artblack01 from New Mexico on February 23, 2013:

I am glad there are people like you spreading the truth rather than propagating lies. Love your hubs.

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