HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Oct 06, 2012, 07:59 AM
darn you, kakka carrot cake.
derpron's Avatar
Australia, WA, Perth
Joined Aug 2012
1,018 Posts
Discussion
disadvantages of having a flat wing?

i know that having a wing that has more thickness on the front and less at the back creates more lift but what happens if i just made a flat foam board wing?
derpron is offline Find More Posts by derpron
Reply With Quote
Sign up now
to remove ads between posts
Old Oct 06, 2012, 08:11 AM
gpw
“There’s no place like Foam”
gpw's Avatar
United States, LA, New Orleans
Joined Jul 2002
24,105 Posts
Flat wings work a treat ... no worries !!!
gpw is online now Find More Posts by gpw
Reply With Quote
Old Oct 06, 2012, 08:18 AM
Registered User
Dave Barrow's Avatar
Ky
Joined Feb 2003
1,490 Posts
You can enhance your flat wing using Kfm
http://www.rcgroups.com/forums/showthread.php?t=1296458
Dave Barrow is online now Find More Posts by Dave Barrow
Reply With Quote
Old Oct 06, 2012, 08:46 AM
darn you, kakka carrot cake.
derpron's Avatar
Australia, WA, Perth
Joined Aug 2012
1,018 Posts
Quote:
Originally Posted by gpw View Post
Flat wings work a treat ... no worries !!!
are you sure? my dad said that i have to have a curvature and thickness at the front of the wing to create more lift but all of my scratchies have flat wings. could you tell me the disadvantages of it?
derpron is offline Find More Posts by derpron
Reply With Quote
Old Oct 06, 2012, 08:59 AM
Picture a worm wearing goggles
snipeworm's Avatar
United States, CA, Roseville
Joined Feb 2012
1,890 Posts
The only disadvantage is that you will not get lift from your wings. Instead a flat wing will cut through the air and ride on it but not actually get any altitude from having a negative air pressure on the top of the wing. In fact flat wings have some of their own advantages for small aircraft such as rc planes. Flat wings are easiest to build, are lightweight, and when built true and straight are not prone to ballooning or having poor flight qualities due to improper angle of attack. The downsides are that generally a true airfoil can fly slower, and a built up wing is generally stronger.
snipeworm is online now Find More Posts by snipeworm
Reply With Quote
Old Oct 06, 2012, 09:02 AM
Build straight - Fly twisty
Whiskers's Avatar
Australia, QLD, Little Mountain
Joined Feb 2010
4,209 Posts
You asked gpw if he is sure?
Gee! He's only built about 57,000,000 planes. I think he's sure
This is how a flat-winger can fly.
IITOP 2012 F3P-AM Donatas Pauzuolis (2 min 0 sec)
Whiskers is offline Find More Posts by Whiskers
Last edited by Whiskers; Oct 06, 2012 at 09:08 AM.
Reply With Quote
Old Oct 06, 2012, 09:20 AM
Crashmaster
Swammy1979's Avatar
United States, CA, Lakewood
Joined Jul 2012
199 Posts
Quote:
Originally Posted by Whiskers View Post
You asked gpw if he is sure?
Gee! He's only built about 57,000,000 planes. I think he's sure
This is how a flat-winger can fly.
http://www.youtube.com/watch?v=-zh5COVVwVA
Pretty badass video.....makes me wanna learn 3-D!! Baby steps, though....baby steps.
Swammy1979 is offline Find More Posts by Swammy1979
Reply With Quote
Old Oct 06, 2012, 09:27 AM
Registered User
maurice076's Avatar
United States, MI, Warren
Joined Aug 2011
641 Posts
Try it!Many plans call for just a flat wing.Or you can do an experiment,make a simple plane where you can change wings,then try and fly them in the same enviroment and see which you like.THe c.g may change with each wing,so do glide tests prior and adjust battery.
maurice076 is offline Find More Posts by maurice076
Reply With Quote
Old Oct 06, 2012, 09:48 AM
gpw
“There’s no place like Foam”
gpw's Avatar
United States, LA, New Orleans
Joined Jul 2002
24,105 Posts
Wasn’t Totally sure , but after seeing that Video, I’m convinced ... Thanks Whiskers , that IS some IMPRESSIVE flying .... :drool: !!!
gpw is online now Find More Posts by gpw
Reply With Quote
Old Oct 06, 2012, 10:09 AM
Registered User
maurice076's Avatar
United States, MI, Warren
Joined Aug 2011
641 Posts
I fly like that all the time......then I wake up!That was great if he had a breeze he could have flown backwards too
maurice076 is offline Find More Posts by maurice076
Reply With Quote
Old Oct 06, 2012, 10:13 AM
darn you, kakka carrot cake.
derpron's Avatar
Australia, WA, Perth
Joined Aug 2012
1,018 Posts
Quote:
Originally Posted by Whiskers View Post
You asked gpw if he is sure?
Gee! He's only built about 57,000,000 planes. I think he's sure
This is how a flat-winger can fly.
http://www.youtube.com/watch?v=-zh5COVVwVA
yeah but the thing is with 3D planes, they are basically helicopters that can glide a little. and iv build a meter long combat plane that's powered by a little blue wonder.
derpron is offline Find More Posts by derpron
Reply With Quote
Old Oct 06, 2012, 10:19 AM
Hot glue held together by foam
United States, WA, Vancouver
Joined Aug 2010
2,545 Posts
Flying backwards

Quote:
Originally Posted by maurice076 View Post
I fly like that all the time......then I wake up!That was great if he had a breeze he could have flown backwards too
4D rc indoor electric plane (2 min 44 sec)
balsa or carbon is online now Find More Posts by balsa or carbon
Reply With Quote
Old Oct 06, 2012, 10:26 AM
Registered User
maurice076's Avatar
United States, MI, Warren
Joined Aug 2011
641 Posts
O.k. you lost me on that one.Reversable motor?Or just trickery?
maurice076 is offline Find More Posts by maurice076
Reply With Quote
Old Oct 06, 2012, 10:30 AM
gpw
“There’s no place like Foam”
gpw's Avatar
United States, LA, New Orleans
Joined Jul 2002
24,105 Posts
Likely a reversible prop ... Cool eh ???
gpw is online now Find More Posts by gpw
Reply With Quote
Old Oct 06, 2012, 10:36 AM
I don't want to "Switch Now"
pmackenzie's Avatar
Toronto (Don Mills), Canada
Joined Dec 2002
16,607 Posts
Quote:
Originally Posted by snipeworm View Post
The only disadvantage is that you will not get lift from your wings. Instead a flat wing will cut through the air and ride on it but not actually get any altitude from having a negative air pressure on the top of the wing.
Sorry, but this is incorrect.

A flat plate wing is just like any symmetrical wing and can generate lift. The mechanism for lift generation is the same for all airfoil sections. Call it flow turning or bound vortex or whatever you want but the end result is the same.
Higher velocity flow on top relative to the bottom, hence lower pressure on top than on the bottom.

The only difference is that it can't generate as much lift, and will make more drag doing it.

Good little applet here that lets you play around with sections, including flat plates, and see the effect on lift and drag:

http://www.grc.nasa.gov/WWW/k-12/airplane/foil3.html

Flat plates work fine when the model is lightly loaded, drag is not an issue, and/or you want to spend a lot of time post-stall anyway. Pretty much defines 3D flight.

Pat MacKenzie
pmackenzie is offline Find More Posts by pmackenzie
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Mr. Romney Will Have One Read Disadvantage in the Upcoming Debates LcJ Life, The Universe, and Politics 22 Sep 29, 2012 03:41 PM
Discussion Depron jets,flat wing, how big Fly Boy3 Foamies (Scratchbuilt) 6 Sep 12, 2012 11:22 PM
Help! Fiberglassing flat wings and stabs. Lt599 Composites Fabrication 4 Sep 01, 2012 10:26 PM
Discussion who have used this servo tester,can tell me the advantage and disadvantages?? sylvia8866 Radios 3 Aug 20, 2012 12:20 PM
Discussion who have used this servo tester,can tell me the advantage and disadvantages?? sylvia8866 Radios 0 Aug 20, 2012 02:43 AM