HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Nov 25, 2009, 10:37 AM
Registered User
thurps's Avatar
Crescent City. Ca.
Joined Nov 2008
189 Posts
Question
Rounding wing tips

Building a Fat Albert. I have been looking at several plank build threads and have noticed quite a variation in the shape of the wing tips. Is there any real advantage to rounding the wing tips? If so, how much or what shape.

Thanks, K.
thurps is offline Find More Posts by thurps
Reply With Quote
Sign up now
to remove ads between posts
Old Nov 25, 2009, 11:27 AM
Registered User
United States, OR, Tualatin
Joined Apr 2005
2,436 Posts
A lot less drag. It is probably more critical on a wing because of the inhearent stability issues that wings have. maybe try detatachable wing tips and see how that changes things.
TomFlyer is online now Find More Posts by TomFlyer
Reply With Quote
Old Nov 25, 2009, 02:24 PM
Crikey never leave beer behind
steve wenban's Avatar
Mt Annan Sydney Australia
Joined Dec 2003
23,055 Posts
Another good reason a round tip is a lot less susceptible to damage on landing square edges tend to be a weak point and suffer badly when impact occurs.
SteveW IMHO
steve wenban is offline Find More Posts by steve wenban
Reply With Quote
Old Nov 25, 2009, 04:48 PM
Registered User
Hexosex's Avatar
Cornwall, UK
Joined Oct 2006
1,089 Posts
Quote:
Originally Posted by steve wenban View Post
Another good reason a round tip is a lot less susceptible to damage on landing square edges tend to be a weak point and suffer badly when impact occurs.
SteveW IMHO
I second both as its going to be more efficent as the vortex's (= drag) wont be so bad on the tips at high speeds.
Hexosex is offline Find More Posts by Hexosex
Reply With Quote
Old Nov 25, 2009, 06:07 PM
Just Toss It !!!
MATIN's Avatar
United States, CA, San Diego
Joined May 2004
5,777 Posts
Quote:
Originally Posted by Hexosex View Post
..... its going to be more efficent as the vortex's (= drag) wont be so bad on the tips at high speeds.
Not quite sure about that......The Mooney 201, one of the fastest GA planes, has square wingtips.

Matin
will throw in grenade once in a while.....
MATIN is online now Find More Posts by MATIN
Reply With Quote
Old Nov 25, 2009, 06:11 PM
Crikey never leave beer behind
steve wenban's Avatar
Mt Annan Sydney Australia
Joined Dec 2003
23,055 Posts
Yeah but its a got steaming great metal whizz bang noise maker suck in its nose.
SteveW
steve wenban is offline Find More Posts by steve wenban
Reply With Quote
Old Nov 25, 2009, 06:16 PM
Just Toss It !!!
MATIN's Avatar
United States, CA, San Diego
Joined May 2004
5,777 Posts
Drag is drag!.......The noisy people hate it as much as the silent types...

Matin
MATIN is online now Find More Posts by MATIN
Reply With Quote
Old Nov 25, 2009, 06:22 PM
Crikey never leave beer behind
steve wenban's Avatar
Mt Annan Sydney Australia
Joined Dec 2003
23,055 Posts
Drag to thrust ratio is alot easier to handle than drag over sink it's called a throttle
SteveW ex fixed wing power flyer (full size)
steve wenban is offline Find More Posts by steve wenban
Reply With Quote
Old Nov 25, 2009, 06:32 PM
Just Toss It !!!
MATIN's Avatar
United States, CA, San Diego
Joined May 2004
5,777 Posts
You mean to tell me the Mooney designer could squeeze out a few knots out of the 201 with a mere rounding of the tips and didn't.......That moron!!!

Matin
MATIN is online now Find More Posts by MATIN
Reply With Quote
Old Nov 25, 2009, 07:07 PM
Crikey never leave beer behind
steve wenban's Avatar
Mt Annan Sydney Australia
Joined Dec 2003
23,055 Posts
No I was not saying that in any way, some thing else about the 201 it tended to porpoise at cruise . Also there's a huge aerodynamic difference between a full size powered aircrafts wing and a lump of foam thats measured with a vernier marked with a thick black marker pen and cut with an axe
SteveW
P.S I'm sure that modifications could be made to the 201 to improve its O/all performance the same can be said of any aircraft or car for that matter.
steve wenban is offline Find More Posts by steve wenban
Reply With Quote
Old Nov 25, 2009, 07:19 PM
Registered User
thurps's Avatar
Crescent City. Ca.
Joined Nov 2008
189 Posts
How about chopping off the end at a 45 deg. with an ax?
thurps is offline Find More Posts by thurps
Reply With Quote
Old Nov 25, 2009, 07:25 PM
Crikey never leave beer behind
steve wenban's Avatar
Mt Annan Sydney Australia
Joined Dec 2003
23,055 Posts
that works to
steve wenban is offline Find More Posts by steve wenban
Reply With Quote
Old Nov 25, 2009, 07:30 PM
Aerobatics!
JGAF's Avatar
United States, CA, Carlsbad
Joined Nov 2007
2,377 Posts
Quote:
Originally Posted by thurps View Post
How about chopping off the end at a 45 deg. with an ax?
You have to get video though.
JGAF is online now Find More Posts by JGAF
RCG Plus Member
Old Nov 25, 2009, 07:44 PM
Just Toss It !!!
MATIN's Avatar
United States, CA, San Diego
Joined May 2004
5,777 Posts
Quote:
Originally Posted by steve wenban View Post
No I was not saying that in any way, some thing else about the 201 it tended to porpoise at cruise . Also there's a huge aerodynamic difference between a full size powered aircrafts wing and a lump of foam thats measured with a vernier marked with a thick black marker pen and cut with an axe
SteveW
P.S I'm sure that modifications could be made to the 201 to improve its O/all performance the same can be said of any aircraft or car for that matter.
I understand......But would changing the wingtips of the 201 reduce the drag??!!!!

Not trying to be a pest here.......I just want somebody to show me some data.

For years I've been asked the same question about wingtips. After talking to people a lot smarter than myself I didn't learn a whole lot.
Mind you, I've never had or built a glider with square tips. My gut instinct tells me thinned and rounded tips are better.

If someone out there has the data please point me in the direction.
And I beg you.....stick with the low R numbers please!

Matin
remembers the porpoising but didn't mind it......it keeps the pilot awake!
MATIN is online now Find More Posts by MATIN
Reply With Quote
Old Nov 25, 2009, 08:35 PM
Crikey never leave beer behind
steve wenban's Avatar
Mt Annan Sydney Australia
Joined Dec 2003
23,055 Posts
personally I dont think rounding the tips has any significant effect on planks or Chevron wings other than reducing damage I believe that the L/edge shape as a whole has much more to do with increased, decreased performance . It has been noticed that if the leading edge is left slight fatish at the tip on a chervon wing that the old death sprial seem to be greatly decreased , but thats only by exprience not by documented data or wind tunnel tests. I think the best we can hope for is a compromise when it come to foam planks and chevrons build it clean build it true and throw it off a mountian as for improving the performance of the 201 rather than decreasing the wing area by rounding the tips it would probably be better to add wingtip fence or a small winglet just a thought.
SteveW
steve wenban is offline Find More Posts by steve wenban
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Wing Dragon/Wing Dragon 4/Begin-Air Series Planes Tips & Tricks Sir Raleigh Parkflyers 1128 Jun 23, 2012 07:45 AM
Discussion supra wing tips with no spars fishdude Composites Fabrication 0 Sep 12, 2009 11:40 AM
Discussion Tiger moth wing tips Dervall The Builders Workshop 20 Sep 11, 2009 05:50 PM
Discussion Any tips for my first flight with a low wing plane? Warthog_Fan Fuel Plane Talk 4 Sep 06, 2009 07:53 AM
New 24in flying wing need tips ideas and post pics or your wing here sylair Foamies (Kits) 37 Aug 17, 2003 06:05 PM