Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Calling 737 Chaps - Whats this bit do ?

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

Calling 737 Chaps - Whats this bit do ?

Thread Tools
 
Search this Thread
 
Old 16th Feb 2002, 03:27
  #1 (permalink)  
Thread Starter
 
Join Date: May 1999
Location: Can't remember
Posts: 159
Likes: 0
Received 0 Likes on 0 Posts
Question Calling 737 Chaps - Whats this bit do ?

Sorting out old photos I came across this one, it was taken some 7 years ago on final to Dublin.. .Observe very carefully at this picture, I may be asking questions



The pic shows a B737-200 wing with either approach or land flap set with vapour coming from the end of the flap, water vapour! nothing unusual in this. or so I thought but look carefully there appears to be a pipe at the end of the flap that looks to be venting the vapour.



As I am pretty certain that the 737 has no fuel dumping system and I really don't think you would be dumping fuel on final anyway. I began to wonder what it was, Is it part of the aircraft that does something else and just looks like is venting or is it some thing on the ground that just happened to be in the right place on the photo.

Any 737 guys out there care to comment ????

Sorry chaps but its been bugging me for days
Squealing Pig is offline  
Old 16th Feb 2002, 04:06
  #2 (permalink)  
 
Join Date: Aug 2000
Location: Berkshire
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
Wink

That 'pipe' is something on the ground which just looks like it is attached to the wing by the position in which it was taken. There is no pipe in that position on the 737. Looking closely at your picture it seems to be reflections of sunlight from a building. The vapour which is present is caused by differential pressures brought about by the flaps. Hope this clears up your query! (Ex 737 driver)!
Red 69 is offline  
Old 16th Feb 2002, 07:17
  #3 (permalink)  
Moderator
 
Join Date: Apr 2001
Location: various places .....
Posts: 7,187
Received 97 Likes on 65 Posts
Post

Bit hard to tell what the photo contains .. however the flaps leave a fairly strong trailing vortex and in conditions of moderate to high humidity the core will be seen due to condensation.

A characteristic of any vortex is a significant radial pressure gradient. The pressure reduction is associated with an adiabatic temperature drop .. the RH increases and at dew point you have a visible record of the vortex core in the condensate.

This is probably what you were seeing, I suspect ?

[ 23 February 2002: Message edited by: john_tullamarine ]</p>
john_tullamarine is offline  
Old 16th Feb 2002, 07:31
  #4 (permalink)  
 
Join Date: Aug 1998
Location: Ex-pat Aussie in the UK
Posts: 5,797
Received 121 Likes on 58 Posts
Post

Send the photo to the "Chemtrail" guys, they would love it!
Checkboard is offline  
Old 16th Feb 2002, 12:00
  #5 (permalink)  
 
Join Date: Dec 2001
Location: Position info not valid
Posts: 112
Likes: 0
Received 0 Likes on 0 Posts
Post

Definately no pipe fitted on the wing-it is definately a building on the ground and if your eyes are really good you can see a guy on the roof of the building installing a TV aerial ???
whatbolt is offline  
Old 16th Feb 2002, 15:13
  #6 (permalink)  
 
Join Date: Feb 2001
Location: UK
Posts: 462
Likes: 0
Received 0 Likes on 0 Posts
Cool

have to agree - think your seeing things.

Maybe Elvis is on the other wing ?
Golden Rivet is offline  
Old 18th Feb 2002, 18:54
  #7 (permalink)  
Thread Starter
 
Join Date: May 1999
Location: Can't remember
Posts: 159
Likes: 0
Received 0 Likes on 0 Posts
Post

Thanks, the more I look at it the more plainly obvious to me now that its a building.

Golden Rivet, Elvis was sat next to me so could not on be the other wing (now I am seeing things <img src="tongue.gif" border="0"> )

Might send it to chemtrails - wind em up and watch em dance
Squealing Pig is offline  
Old 23rd Feb 2002, 09:35
  #8 (permalink)  
 
Join Date: Feb 1998
Location: Formerly of Nam
Posts: 1,595
Likes: 0
Received 0 Likes on 0 Posts
Post

Yeh John T is 100% correct. You see it a lot in conditions of high humidity. The 747-classic was the best at this during TO or ldg with high wing loadings. Youd swear blind there was fuel p!ssin out off the tops of the wings!
Slasher is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.