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

Wing Extensions

Wikiposts
Search

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

Wing Extensions

Thread Tools
 
Search this Thread
 
Old 27th June 2012 | 09:38
  #1 (permalink)  
Thread Starter
 
Joined: Sep 2011
Posts: 23
Likes: 0
From: Queensland, Australia
Wing Extensions

Hi everybody,

I would like to know the effects of MTOW is with adding wingtip extensions onto a light aircraft.

Not winglets, not fences, just an add-on extension of about a foot or so to make the wing longer.
bobthebowler is offline  
Reply
Old 27th June 2012 | 13:49
  #2 (permalink)  

Do a Hover - it avoids G
 
Joined: Oct 1999
Posts: 2,201
Likes: 0
From: Chichester West Sussex UK
I would suggest that will depend on what determines the MTOW of the unmodified aeroplane.

For example if that was determined by wing structural strength in bending then it could reduce it. On the other hand if it was to keep the stall speed below some certification limit then it would improve. The question is not as easy as it sounds - but you may know that already!
John Farley is offline  
Reply
Old 4th July 2012 | 04:58
  #3 (permalink)  
20 Anniversary
 
Joined: Apr 2005
Posts: 141
Likes: 15
From: yyz
look here
Wing-X Stol

I think any upgross has to be fuel in the tiptanks though I maybe mistaken though
rigpiggy is offline  
Reply
Old 4th July 2012 | 20:58
  #4 (permalink)  
20 Anniversary
 
Joined: Feb 2005
Posts: 4,581
Likes: 0
From: flyover country USA
An aftermarket kit did this for the old Republic SeaBee; but I'm sure a thorough structural relook at the whole wing and strut was part of the job.
barit1 is offline  
Reply
Old 5th July 2012 | 12:08
  #5 (permalink)  
 
Joined: Apr 2008
Posts: 343
Likes: 0
From: Australia
I did a wingtip extension on a 182 to increase the MTOW 100kg
Engineer_aus is offline  
Reply
Old 6th July 2012 | 13:19
  #6 (permalink)  
20 Anniversary
 
Joined: Feb 2005
Posts: 4,581
Likes: 0
From: flyover country USA
That indicates, of course, that the basic 182 has plenty of structural margin. You have increased the loading, AND moved the spanwise center of lift outboard, and still met structural requirements. Impressive work by Cessna!
barit1 is offline  
Reply
Old 14th July 2012 | 05:19
  #7 (permalink)  
20 Anniversary
 
Joined: Sep 2001
Posts: 53
Likes: 3
From: Right Here
Yes, it depends on who is making what assumptions. The Beech 18 had a STC to increase gross weight by clipping the wingtips to reduce the wing bending moments, and there were many more which allowed you to increase the gross weight by - among other things - putting bigger wingtips on to increase the wing area for more lift!
Jamesel is offline  
Reply
Old 14th July 2012 | 08:39
  #8 (permalink)  
15 Anniversary
 
Joined: Aug 2006
Posts: 169
Likes: 19
From: Nairn, Highland
Many gliders have choice of wingtips depending on the category under which they fly.

Eg the very popular LS8 can be flown in 15 metre mode (small wingrtips) for 15 metre competitions or in 18 metre mode (larger wingtips) for 18 metre and Open class competitions. Different max weight limits apply.

Jack

Last edited by jackharr; 14th July 2012 at 08:39.
jackharr is offline  
Reply
Old 14th July 2012 | 17:24
  #9 (permalink)  
25 Anniversary
 
Joined: Dec 1998
Posts: 4,282
Likes: 6
From: Escapee from Ultima Thule
PA60 Aerostar has a mod that increases MTOW with a wingtip extension.
Tinstaafl is offline  
Reply
Old 14th July 2012 | 19:01
  #10 (permalink)  
 
Joined: Dec 2009
Posts: 147
Likes: 0
From: Norway
Angel Cessna 182P/Q GWI

That indicates, of course, that the basic 182 has plenty of structural margin. You have increased the loading, AND moved the spanwise center of lift outboard, and still met structural requirements. Impressive work by Cessna!
Impressive indeed! Now, having said that, they could have done their customers better in some cases. By that I mean Cessna increased the 182's gross on several occasions (strictly by analysis) but didn't allow "already sold" 182s the benefit. An example: For the 1981 182R model, MGTOW went from 2950 to 3100 pounds (1340 to 1409 kg). There were NO structural changes made to allow this, just engineering paperwork. But there was no opportunity for over 4000 owners of STRUCTURALLY IDENTICAL 182P and 182Q (1972 - 1980) models to benefit.

Today there is, only because an aftermarket STC (paperwork only) does for the 182P/Q what Cessna did for the 182R. Don't ask me how I know this.

The Wing-X wing extension mentioned earlier is certainly a great STC for some of the earlier airplanes, but it requires structural mods and costs money.

Can the 182 GW go beyond 3100 lbs? From a true certification standpoint, probably not. I believe it has to do with a requirement regarding asymetrical wing loading. (Float equipped 182s are a special case). On a "Special Flight Permit" they are indeed allowed up to 130% of 3100 with certain operating limitations, but that's a special case.

So, as barit1 correctly points out:

...the basic 182 has plenty of structural margin.

Cheers,

Tom
Trolltuner is offline  
Reply

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 © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.