Blackbird1331 From United States, joined Apr 2004, 1878 posts, RR: 1 Posted (5 years 6 months 2 weeks 6 days 6 hours ago) and read 800 times:
What causes them? My guess is the super hot exhaust meeting the super cold air. But where does the moisture come from? Is moisture in the exhaust? And, some scientists think they linger as clouds and form a heat shield in the atmosphere. Is there research being done on this by engine manufacturers?
Cameras shoot pictures. Guns shoot people. They have the guns.
Timz From United States, joined Sep 1999, 5388 posts, RR: 6 Reply 2, posted (5 years 6 months 2 weeks 6 days 6 hours ago) and read 774 times:
I guess there's no "moisture" in the exhaust, but there's plenty of water vapor. That's what burning is-- fuel and oxygen being converted to water and carbon dioxide.
Espion007 From Denmark, joined Dec 2003, 1691 posts, RR: 0 Reply 7, posted (5 years 6 months 2 weeks 6 days 3 hours ago) and read 724 times:
damn you Pu151! you beat me too it!
contrails form when hot engine exhaust hits cold air very fast.droplets stick togeather to form something similar to clouds.Same thing happens with your breath on a cold day,just on a smaller scale,and not as cool
Avioniker From United States, joined Dec 2001, 1098 posts, RR: 17 Reply 8, posted (5 years 6 months 2 weeks 5 days 14 hours ago) and read 637 times:
The issue is being addressed very highly by manufacturers. It is of extreme interest to the military who don't want to give a visual cue to anti-aircraft emplacements.
There is considerable research being done in Tulahoma TN at the Arnold Test Facility and other locations around the world.
Along with providing a visual locator the contrails cause a focal point for Infrared variances.
One of the things being looked at is the possibility of gleaning more energy from the engines. One theory being that if the air coming from the tailpipe can be caused to be as close as possible to the air into the intake the engine has used more of the available energy and it'll be harder to target as well.
That is, of course, impossible with current technology but P&W came close with the F100 engine at full power without reheater. They got it down to a 100deg F difference between intake and exit in 1974.
I wonder what they're doing now???
One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533
Blackbird1331 From United States, joined Apr 2004, 1878 posts, RR: 1 Reply 9, posted (5 years 6 months 2 weeks 5 days 7 hours ago) and read 605 times:
Thank you Avioniker, that is the information I was looking for. I hope to post some information on any continuing research in this area that I might find.
Cameras shoot pictures. Guns shoot people. They have the guns.