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- vroom101, on 10/11/2007, -2/+82Link to a bigger version of this beautiful photo:
http://www.airliners.net/open.file/0239080/L/
Spectacular photo of U.S. Air Force F-15 Eagle and Soviet Mikoyan-Gurevich MiG-29 contrails:
http://chamorrobible.org/images/photos/gpw-200701a-UnitedStatesAirForce-DFST9005759-vigilance-USAF-F-15-fighter-jets-intercept-two-USSR-MiG-29-aircraft-medium.jpg
via http://chamorrobible.org/gpw/gpw-200701.htm (photo #1) which also has the interesting story where Canada plays a central role. - Otto, on 10/11/2007, -5/+60Yes, they're spraying dihydrogen monoxide all over the skies!
http://www.dhmo.org/ - EridanMan, on 10/11/2007, -0/+31@Infowars
Modern Turbines run extraordinarily 'clean' compared to your typical combustion engine. This isn't out of any benevolence factor, its a simple question of economics... aircraft require tons of energy, in any reaction that requires tons of energy, minor efficiency savings lead to large monetary savings, meaning there is incentive to make and keep everything working properly. Hell, the Trent-500 engine used on the 777 (as well as the entire next generation of aircraft turbines) all run at greater than 50% thermodynamic efficiency at cruise... (If you didn't fail high-school chemistry, you'll know that is _obscenely_ high for any form of controlled oxidation reaction). This is also why the whole concept of "chem-trails via fuel additives" is ludicrous... those engines are designed to excruciatingly strict tolerances, even the mildest inconsistencies in fuel (or airspeed, or cruise mach) cause a dramatic fall-off in efficiency that would cause uproar among the world's airlines immediately.
Now, by 'clean' I mean its dumping large amounts of H20 and C02 into the atmosphere... the enviromental effects of _THAT_ are... well... ok, maybe not so good (we really don't know). The C02, being heavier than the surrounding gas, will tend to settle to the surface quickly, and is hence little different than any other CO2 release (Bad if and only if (as is the case now) the rate of CO2 processing in the environment is less than its rate of production... something we really should work on). The H20 on the other hand, is fairly minuscule compared to evaporation, and there are mechanisms in the atmosphere to diminish it if it gets to high (its called rain;)). The question/issue is, whether or not the _SOLIDIFICATION_ of the H20 is a problem... Basically, what was super-saturated clear air is now a natural, normal cloud... there are more natural, normal couds in the sky, is this a danger.
Honestly, the verdict is out on this one. - KennMac, on 10/11/2007, -14/+43Actually it's a vapor trail. Nice try, you hippie.
- EridanMan, on 10/11/2007, -3/+31Yes, they are a massive trail of Dihydrogen monoxide (certainly a chemical) in its solid form.
Jet Engines produce two bi-products, CO2 and H20. in 'normal' contrails, the amount of H20 produced pushes the the local air above its saturation threshold, but only after the exhaust cools down a bit (the water carrying capacity of air depends directly on its temperature), so the contrail appears substantially behind the aircraft. If the ambient moisture level is also substantially below carrying capacity, the moisture then tends to disperse into the free air around, and the contrail dissipates behind the aircraft (the rate of dissipation is actually a relatively good measure of the level of saturation at that altitude). In a super-saturated contrail, however, there is already FAR more moisture in the air it than it can hold (usually only because the air has cooled down, thus lowering its carrying capacity, but no catalyst has been presented to initiate the state change from vapor to solid.)
The aircraft, in this case, is just a massive catalyst..where a 'typical' contrail is composed of simply the H20 created in the cumbustors, a super-saturated-contrail contains that plus tons of ambient H20 in the air that is simply 'waiting' for any excuse to become solid. Hence, ALL air which contacts the aircraft, forms a cloud, not simply the air that runs through the combustors.... The result are these super thick, long-lived contrails, which some, ignorant of the basic laws of chemistry and physics, mistakenly believe to be somehow nefarious.
This is a beautiful picture for more than just the contrail, however... the definition in the lift-induced vortices is spectacular... You can clearly see the process that keeps aircraft aloft. (Hint, there is only one way that planes fly - they exert a force on the air that is _PRECISELY_ equals to the downward force of gravity on their mass). Impart a strong force on any viscous fluid, and fluid will rush in behind the force to prevent creation of a vacuum. This is a wingtip vortex. They're truly beautiful (and dangerous) artifacts of simple fluid dynamics.
Pilot's... Just think about this picture next time you here "caution, wake turbulence..." and give it the respect it deserves;) - garf12, on 10/11/2007, -6/+29Chemtrails that are dispersed by the government to control the citizens minds! riiiiighhhtt....
- ryanknapper, on 10/11/2007, -10/+33@sandifish:
No, he meant chemtrails.
http://en.wikipedia.org/wiki/Chemtrails - majordannyboy, on 10/11/2007, -1/+23FL350 means 35,000 feet. It stands for Flight Level 350 and everything is multiplied by 100 so FL25 is 2500 feet and FL 420 is 42,000 feet.
- EridanMan, on 10/11/2007, -0/+22Your car only manages to eek between 20 to 25% of the available energy in hydrocarbon fuel out as useful work. That aircraft is operating closer to 45% thermodynamic efficiency, and modern aircraft/engines have pushed that margin above 50%.
They are among some of the most efficient rapid-oxidation-to-moment reactors every created by man... hardly 'bad fuel economy' - inactive, on 10/11/2007, -0/+19Show me a car that flys, idiot.
And that plane also carries a few more people than your car does. - KennMac, on 10/11/2007, -4/+21Go back to commenting on youtube, plz. kthxbye.
- darvian, on 10/11/2007, -3/+18"Take that Al gore"
Wasn't that Al Gore's private jet? - SpaceMonkeyZero, on 10/11/2007, -13/+28Better wear your respirators and tinfoil hats!
@sandfish: vvv I think he missed a /s - KennMac, on 10/11/2007, -1/+16It's pretty sweet to have a window seat behind the wing and see these form right out of the engine exhaust.
- NSMike, on 10/11/2007, -0/+14I guarantee the sum total of jet pollution in one day is a fraction of that which is caused by cars in the same amount of time.
- twinklyJesus, on 10/11/2007, -2/+16I wonder what the fuel economy would be for your eco-friendly car if:
it could carry 300 passengers
at nearly 400 mph
at 35,000 ft.
non-stop for 3,000 miles (min range)
the myopia is palpable! - NSMike, on 10/11/2007, -0/+14I love Airliners.net. They have some damn good photography.
- vroom101, on 10/11/2007, -3/+17dear diggers -- da dudes & da dudettes -- here is the photographer's website...he's a pilot too:
Josef P. Willems
http://www.joe-photo.com/
Josef P. Willems photo gallery
http://www.joe-photo.com/gallerie.html
More of his photos on airliners.net
http://www.airliners.net/search/photo.search?photographersearch=Josef%20P.%20Willems&distinct_entry=true - SmokeMeAKipper, on 10/11/2007, -0/+13Yeah the LOGO really ruins it.
- sandfish, on 10/11/2007, -12/+25Contrail is correct...
http://en.wikipedia.org/wiki/Contrail
@SpaceMonkeyZero
Thought he might have =) - RogerStrong, on 10/11/2007, -2/+15Not that they don't pollute, but what this shows is how much water vapor they put out.
You get the same thing from cars when it's -40. The carbon-monoxide is still invisible, but the water vapor isn't. Some mornings it can be hard to see in traffic. - SpaceMonkeyZero, on 10/11/2007, -0/+13That's no 747! That's Xenu's spaceship!
- EridanMan, on 10/11/2007, -0/+13Umm... yes it is.
The forebody hump is somewhat masked by the reflection of the sun on the fuselage, but the figure is undeniably 747. - EridanMan, on 10/11/2007, -2/+14One word to describe you: Ignorant.
- EridanMan, on 10/11/2007, -2/+14@superpotential-
No reason to be freaked out, what you are seeing is standard flight-level separation used by all aircraft operating in Class-A (or its international equivolent) airspace. East-bound flights use Odd flight levels, west bound flights use even flight levels. Its standard practice. - SerifTheRobot, on 10/11/2007, -1/+12777s have 2 engines. That is a 747 alright, which has 4. ...not to mention the 747's lovely lady lump. Check it out.
- Smills, on 10/11/2007, -0/+11@ mchoffa
There are many names for it... Either of those are acceptable. - soupnrc, on 10/11/2007, -7/+18Contrail.... It's just super condensed moisture that freezes once it leaves the jets.
- flygirl62, on 10/11/2007, -0/+11Actually, flight levels aren't used until above some specific altitude (18,000 ft in the USA, but different elsewhere). Below that, altitude is in feet above sea level.
Above that, you go to an altimeter setting of 29.92 and that's when you start calling them flight levels... In fact, one of the reasons they are called that is that it may or may not be very close to your actual altitude... depends on the atmospheric pressure that day.
For more info: http://en.wikipedia.org/wiki/Flight_level
But, yes... multiply the FL by 100 to get the altitude, for all practical digg purposes. :-) - inactive, on 10/11/2007, -0/+11what are you talking about? it is a 747. it has a hump, if that's what you care about.
- nesibus, on 10/11/2007, -2/+13um no....777's have 2 engines...not 4.
- EridanMan, on 10/11/2007, -0/+10@twinklyJesus
Piston Rings? Head Gasket?
I actually laughed out loud at that. I hope that's what you intended. - nesibus, on 10/11/2007, -0/+10Thanks for the info, I've never heard of that before.
- bills534, on 10/11/2007, -3/+12"747 producing supermassive contrails at 35,000 feet PIC"
Hmm this is a tough one but I think they might be contrails?
Hint: type the word contrails into just about any search engine and the answer you seek shall be found!
here I did the "hard" work for you. from wikipedia:
"Contrails or vapour trails are condensation trails and artificial cirrus clouds made by the exhaust of aircraft engines or wingtip vortices which precipitate a stream of tiny ice crystals in moist, frigid upper air. Being composed of water, the visible white streams are not, in and of themselves, air pollution. However, contrails generated by engine exhaust are inevitably linked with typical fuel combustion pollutants. Contrails might also be considered visual pollution." - EridanMan, on 10/11/2007, -0/+8Spend a winter transatlantic flight on an aircraft's flight-deck and you'll see similar scenes repeated many times... its just that the most passenger view-ports are too small and point the wrong direction to see it happen.
That's standard Flight-level separation, and typical North-Atlantic winter atmospheric conditions (I didn't check to see if that's where the picture was actually taken... but the conditions can exist anywhere in the world, its just typical of the north Atlantic).
The only thing unique about this photo is that the photographer actually took the effort to capture it. - fourcylthrill, on 10/11/2007, -0/+8For those talking about wing vortex
NASA experiment showing the danger of flying behind a big jet.
http://www.youtube.com/watch?v=eF1a37nqDA4 - DIGGerPhelpsND, on 10/11/2007, -2/+9It is a 747.
Read the ***** caption. - jhshukla, on 10/11/2007, -0/+6how are these contrails super massive? you can easily estimate their size from ground and they are of normal size. nice picture though.
- EridanMan, on 10/11/2007, -0/+6@zeejay
I travel to Europe regularly in the winter, and contrails forming off the wings and immediately behind the engines are relatively common over the north Atlantic.
The intensity of the contrail formation depends on the level of saturation. mildly super-saturated air will produce the same effect, but the intensity of the catalyzed contrail will be too minor to notice from the plane (it'll still appear as a long-lived contrail on the ground, however). In order to see the contrail flowing off the wing, generally, you need some pretty serious super-saturation... but as I said, take a trans-atlantic flight during the winter and there's a good chance you'll see wispy streams coming off the wings. - flygirl62, on 10/11/2007, -1/+6@vroom101
Yes, that is exactly what you see there...
Nasty rolling packets of air that can be deadly if you are too close behind a large, slow moving plane. (Believe it or not, the SLOWER the plane is moving, the worse the vortex --- because it's flying at a higher angle of attack)
I was in a small plane that flew through the vortexes once of a DC9... we were MILES behind him and STILL almost got rolled inverted. Fortunately, the pilot was attentive enough to catch it and we didn't.
Oh, and THEN the controller said "Caution, wake turbulence." I think he saw us roll and wanted to get it on the record in case we complained or crashed. :-) - EridanMan, on 10/11/2007, -0/+51. Donuts on a rope have been around for far longer than the chemtrail madness (back in the 80s, the aircraft buffs used to think they were caused by some form of external combustion scram in the SR-71 replacement). I have yet to hear a convincing explanation of exactly what they are, but there are plenty of theories, and a great majority of them are benign. This proves nothign.
2. Ok, your catching stuff in ground based filters... may I suggest you start looking around your town and seeing what's releasing it? There are two basic meteorological principles. Thermal Layers and Jet Stream. Look them up, and you'll see why the entire concept of "spraying" at 18-30 thousand feet is absolutely ludicrous. Again, I am not denying the possibility that a nefarious organization could poison the population. What I am doing is saying that if they were to do it, High-altitude aircraft based "Spraying" is literally the dumbest possible solution imaginable. _WAY_ too many people would need to be in on it, tremendous resources would be needed to lift enough toxins to an altitude where they could ever be even measurable on the ground, and if they were released, the jet-stream would quickly Distribute them everywhere in the world BUT where you were directly above spraying. This isn't that hard people...
3. Many clouds produce weird shimmering effects in the upper atmosphere as well. Completely Inconclusive.
4. I'm afraid I'd need to see pictures of this one because I have no clue what your talking about.
5. Do me a favor. Take a map of the US. Draw a line from every city of population 300,000 plus to every other city of population 300,000 plus, notice how many "grids" and "Xs" Appear. Its called point-to-point, the downfall of the Hub-and-Spoke model, and its radically changed air travel in the US.
The people look at this aren't retards... They're just blinded by a theory-before-evidence mentality... and its both frustrating and sad. They see patterns in the sky, it feels weird to them that there should be patterns and the sky, and they go build this dare I say mythology about what is going on with these patterns int he sky when there are perfectly simple, logical, rational and well understood explanations out there.
All of the evidence, all of the weird looking ***** int he sky, all of the halos and contrails and weird Xs and donuts on a rope don't change one simple fact - Spraying from 20-30 thousand is simply not a physically feasible way to do what these theories say is being done. I mean... how much more plain and simple can I put it?
I would _LOVE_ you to go figure out what all of those various atmospheric phenomena are... truly abjectly and open-mindedly... but in order to actually be openminded, I'm afraid your going to have to forget the theory that is infinitely impractical and fundamentally impossible. - g33b33, on 10/11/2007, -2/+7Anyone notice that contrails have almost NO mass? :-)
Dugg down for using supermassive in a non-black hole context - noseeme, on 10/11/2007, -0/+5The visible part is vapour by the way, not smoke.
- EridanMan, on 10/11/2007, -2/+7Please reference above where I provide a detailed explanation of the various forms of contrails and why they form, and you will see why your posting is in error.
Also, atmospheric circulation between 35000 feet and ground is negligible, so I would not concern myself with "opening my mouth" while staring at a stable, super-saturated contrail. Nor would I find their chemical composition particularly toxic. - NSMike, on 10/11/2007, -0/+5No no no, SpaceMonkeyZero. Don't you know Xenu's ships are DC8s? McDonnell Douglas was a galactic contractor 15 billion years ago, duh.
- twstdroot, on 10/11/2007, -0/+51000 ft above FL350 is 36,000 feet
- djAnakin, on 10/11/2007, -0/+5Photoshops!? No. They're not.
To quote above:
"dear diggers -- da dudes & da dudettes -- here is the photographer's website...he's a pilot too:
Josef P. Willems
http://www.joe-photo.com/
Josef P. Willems photo gallery
http://www.joe-photo.com/gallerie.html
More of his photos on airliners.net
http://www.airliners.net/search/photo.search?photographersearch=Josef%20P.%20Willems&distinct_entry=true " - inactive, on 10/11/2007, -0/+5Acronym for CONdensation TRAIL. A cloud-like streamer or trail often seen behind aircraft flying in clear, cold, humid air. A vapor trail is created when the water vapor from the engine exhaust gases are added to the atmosphere.
- inactive, on 10/11/2007, -3/+8i'd be freaked out if an aircraft was passing that close... and even more so if it was passing in the opposite direction as in this photo
- klick37, on 10/11/2007, -6/+11Those are, indeed, supermassive contrails. Kudos.
-
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