PIA777
Topic Author
Posts: 1841
Joined: Tue Dec 30, 2003 9:39 am

Does Vapor Cause Any Damage To The Wing?

Sat Nov 22, 2003 3:12 am

Hello, Does vapor forming on the wing cause any damage to the wing?

As in this photo


View Large View Medium
Click here for bigger photo!

Photo © Simon Willson




-PIA777
GO CUBS!!
 
OPNLguy
Posts: 11191
Joined: Tue Jun 15, 1999 11:29 am

RE: Does Vapor Cause Any Damage To The Wing?

Sat Nov 22, 2003 3:20 am

>>>Does vapor forming on the wing cause any damage to the wing?

No.

Keep in mind that it's -water- vapor, and the kind in your photo is only there for a short time. If an aircraft can fly in clouds (also water vapor) for extended periods of time, logic dictates that momentary vapor on landling/takeoff is no problem at all, and for that matter, so it flying in clouds for extended periods of time.

Just curious, but why would you think it would cause any damage?
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.
 
unattendedbag
Posts: 2154
Joined: Wed Oct 08, 2003 10:35 pm

RE: Does Vapor Cause Any Damage To The Wing?

Sat Nov 22, 2003 5:55 am

Ever driven through fog or a misty rain? It's about as damaging to your car as water vapor is to the wing of an aircraft. There no possibility of damage.

Unless you don't see the big runway chicken in the fog and you collide with it!
Slower traffic, keep right
 
PIA777
Topic Author
Posts: 1841
Joined: Tue Dec 30, 2003 9:39 am

RE: Does Vapor Cause Any Damage To The Wing?

Sat Nov 22, 2003 7:56 am

I just thought that it might cause friction on the wing and do some damage, or get inside the wing and short out something. I noticed that when the plane goes through the clouds the engine's change color, from a brownish color to a blueish color. When the plane goes through tthe clouds does the water vapor go into the engine and do something???

-PIA777
GO CUBS!!
 
musang
Posts: 788
Joined: Sun Apr 08, 2001 4:11 am

RE: Does Vapor Cause Any Damage To The Wing?

Sat Nov 22, 2003 10:03 pm

Just to be nitpicky, If you can see it, its not water vapour any more. WV is an invisible gas, surrounding us at all times to some extent (humidity). If you can see clouds, fog, the stuff in the PIA photo above etc., the WV has condensed, by means of a drop in temperature and/or pressure, into visible moisture. Condensation.

One hears talk of vapour trails from high flying aircraft. It was WV for a split second as it left the engine, and its actually ice crystals, as the condensation of the water vapour in the exhaust has gone through the liquid stage straight to ice, as its probably less than -45 degrees celsius out there. I always thought that was called sublimation, when it goes straight to ice, but I've never heard of "sublimation trails"!

If a aircraft isn't making trails, its not cold enough, or the pressure isn't low enough, but probably the WV content (i.e. the humidity) isn't high enough, but the WV is still there of course.

It doesn't matter to the engine whether its eats the WV in visible form (clouds, fog,) or invisible. Its there just the same.

You'll see more condensation over wings in the morning, when the air's colder. It doesn't take much of a pressure drop to set it off, which of course happens as a matter of course as the wing generates lift. The humidity must be high as well, which is an expression of how close the air is to its maximum WV content. 30% humidity, for example, means the air is holding 30% of the WV it COULD hold for the existing temp. and pressure.

WV is also responsible for the wing tip trails you see, also on cool, humid mornings. The vortices off the wingtips or the outer rear corners of trailing edge flaps, cause the air to suddenly experience a huge pressure drop. The WV again condenses to visible moisture and by definition isn't WV any more, until it eVAPORates back into the air.

Get all that?!

Hopefully not too rambly.

Regards - Musang
 
wing
Posts: 1357
Joined: Sun Oct 01, 2000 9:10 pm

RE: Does Vapor Cause Any Damage To The Wing?

Sat Nov 22, 2003 10:40 pm

Not unless they are made of candy Smile
follow me on my facebook page" captain wing's journey log"
 
air2gxs
Posts: 1443
Joined: Mon Jun 18, 2001 1:29 pm

RE: Does Vapor Cause Any Damage To The Wing?

Sun Nov 23, 2003 1:33 am

The engine changes color?
 
aloges
Posts: 14842
Joined: Tue Jan 17, 2006 3:38 am

RE: Does Vapor Cause Any Damage To The Wing?

Sun Nov 23, 2003 2:40 am

Musang, great post! You've spoken right from the heart of me, or rather the part-time nitpicky chemistry highschool grad inside me (hope I got the translations right... Big grin)!

However, contrails would have to be called "REsublimation trails" to be 1000% correct.  Big thumbs up
Sublimation is the transgression from solid to gaseous, not the opposite which is resublimation.

But how would that sound anyway, maybe abbreviated to "retails"?!  Nuts
Don't cry because it's over, smile because it happened.
 
musang
Posts: 788
Joined: Sun Apr 08, 2001 4:11 am

RE: Does Vapor Cause Any Damage To The Wing?

Sun Nov 23, 2003 7:22 am

Aloges! I'm glad you straightened that out, as I wasn't sure. The only dictionary I have is dated 1975 and says, for "sublimate", "Convert from solid state to vapour by heat and allow to solidify again" so I thought it went both ways. Long time since I did High School chemistry!

Thanks - Musang

Who is online

Users browsing this forum: gtae07, Horstroad, SAAFNAV, WYLTK and 7 guests