Aileron11 From United States of America, joined Oct 2005, 183 posts, RR: 0 Posted (6 years 5 months 2 weeks 1 day 14 hours ago) and read 1935 times:
I checked to see if this has been discussed before but did not find anything, so my question is, why does some airplanes have contrails that look like they skip, just today I saw three airplanes flying and instead of seeing long continues line I saw the contrail stop and then start again I looked as long as I could see the airplane and it kept happening. Just wondering if any else seen this or maybe even have an answer thanks.
Steeler83 From United States of America, joined Feb 2006, 8811 posts, RR: 19 Reply 1, posted (6 years 5 months 2 weeks 1 day 14 hours ago) and read 1910 times:
It has to do with atmospheric conditions aloft. There must be some little isolated pockets of very dry air aloft for this phenomenon to occur. With more humidity at F.L. 20-something-000 feet, the water vapor discharged from the jets will condense into clouds, or what we see as contrails. If the air is very dry aloft, the vapor cannot condense and crystalize. Therefore no contrail is seen.
Please somebody correct me if I am wrong! I read about contrails in "The National Audaban Society Field Guide to North American Weather. (I don't think Audaban is spelled right btw.) Anyway, that is my source. Did I misinterpret or misread something? Please tell me!!
Do not bring stranger girt into your room. The stranger girt is dangerous, it will hurt your life.
We're Nuts From United States of America, joined Jun 2000, 5705 posts, RR: 22 Reply 2, posted (6 years 5 months 2 weeks 1 day 14 hours ago) and read 1896 times:
It's because they are spraying chemicals as part of a top secret government program.
Aileron11 From United States of America, joined Oct 2005, 183 posts, RR: 0 Reply 3, posted (6 years 5 months 2 weeks 1 day 14 hours ago) and read 1877 times:
Quoting Steeler83 (Reply 1): It has to do with atmospheric conditions aloft. There must be some little isolated pockets of very dry air aloft for this phenomenon to occur. With more humidity at F.L. 20-something-000 feet, the water vapor discharged from the jets will condense into clouds, or what we see as contrails. If the air is very dry aloft, the vapor cannot condense and crystalize. Therefore no contrail is seen.
Please somebody correct me if I am wrong! I read about contrails in "The National Audaban Society Field Guide to North American Weather. (I don't think Audaban is spelled right btw.) Anyway, that is my source. Did I misinterpret or misread something? Please tell me!!
Thanks for the info.
Quoting We're Nuts (Reply 2): It's because they are spraying chemicals as part of a top secret government program.
Steeler83 From United States of America, joined Feb 2006, 8811 posts, RR: 19 Reply 4, posted (6 years 5 months 2 weeks 1 day 13 hours ago) and read 1865 times:
Anytime. Although, I must say that I don't know how accurate that is. I did have a supreme interest in meteorology, but of course, that interest has shifted towards geography and planning.
Quoting Aileron11 (Reply 3): Quoting We're Nuts (Reply 2):
It's because they are spraying chemicals as part of a top secret government program.
i had feeling something like that was happening.
Heheh, yeah this is true as well
I think that the increasing number of really bad drivers has something to do with this, and one royally bad driver practically ran my girlfriend and myself off the road just last night! If he could've gotten any closer to my girlfriend's trunk, he would've been in it...
Do not bring stranger girt into your room. The stranger girt is dangerous, it will hurt your life.
Vref5 From , joined Dec 1969, posts, RR: Reply 5, posted (6 years 5 months 2 weeks 1 day 13 hours ago) and read 1841 times:
Quoting We're Nuts (Reply 2): It's because they are spraying chemicals as part of a top secret government program. shhh
Hahaha
Ahh, yes, the good ol' chemtrails.
Quoting Steeler83 (Reply 1): It has to do with atmospheric conditions aloft. There must be some little isolated pockets of very dry air aloft for this phenomenon to occur. With more humidity at F.L. 20-something-000 feet, the water vapor discharged from the jets will condense into clouds, or what we see as contrails. If the air is very dry aloft, the vapor cannot condense and crystalize. Therefore no contrail is seen.
You've got the rough idea, though there are actually two things that matters here:
1. Low temperature
AND
2. Vapor pressure
It's pretty cold up there every day, but not always the vapor pressure needed. That's why you don't always see contrails.
Basically, if you have sufficient vapor pressure, it will form a "cloud"... and if you don't, it won't. There, that's a bit of my aviation meteorological training put to some use.
Graphic From , joined Dec 1969, posts, RR: Reply 6, posted (6 years 5 months 2 weeks 1 day 13 hours ago) and read 1823 times:
There needs to not only be enough water vapor (not as much as you'd think because jet engines themselves produce a large amount of water vaport), but there also needs to be sufficient nuclei for the vapor to condense on (microscopic dust, smoke particles). When the temperature is so cold that the air cannot hold the water vapor the engines produce, it will condense on the nuclei and a cloud will be visible.
Steeler83 From United States of America, joined Feb 2006, 8811 posts, RR: 19 Reply 7, posted (6 years 5 months 2 weeks 1 day 13 hours ago) and read 1809 times:
Naturally I should've known about cold temperature, OF COURSE!!! Vapor pressure I didn't even think of! THANKS!!!
Quoting Vref5 (Reply 5): Basically, if you have sufficient vapor pressure, it will form a "cloud"... and if you don't, it won't. There, that's a bit of my aviation meteorological training put to some use.
And good training put to good use at that!
Do not bring stranger girt into your room. The stranger girt is dangerous, it will hurt your life.
Steeler83 From United States of America, joined Feb 2006, 8811 posts, RR: 19 Reply 9, posted (6 years 5 months 2 weeks 1 day 12 hours ago) and read 1711 times:
Pihero From France, joined Jan 2005, 3496 posts, RR: 72 Reply 10, posted (6 years 5 months 2 weeks 1 day 5 hours ago) and read 1595 times:
Quoting Steeler83 (Reply 1): It has to do with atmospheric conditions aloft. There must be some little isolated pockets of very dry air aloft for this phenomenon to occur.
Quoting Vref5 (Reply 5): Basically, if you have sufficient vapor pressure, it will form a "cloud"... and if you don't, it won't.
All true, but if you both go just a bit further, it is a sure sign of clear air turbulence be it due to a wave or some drastic convective movements of the air mass.
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