Rounding Landing Gear Edges, Etc.  
View related threads: (in this forum | in all forums)

Tower Hobbies
Enter up to 4 keywords or Tower stock numbers
Logged in as Guest



Users viewing this topic: none
  Printable Version
       


Jet Hangar Hobbies LTV A-7 Corsair II - RTF
Seller:  mikegpresario
Details:   $2,850.00   |  8/26/2008   |  Classified Ad
We will rotate YOUR AD in this spot if you select "Forum Featured" when placing or editing your ad!

All Forums >> RC Airplanes >> Aerodynamics >> Rounding Landing Gear Edges, Etc.
Page: [1]

Login
Message << Older Topic   Newer Topic >>
Rounding Landing Gear Edges, Etc. - 2/27/2002 12:25:45 AM   
Jazzy



Posts: 1103
Joined: 1/8/2002
From: Erie, PA, USA
Status: offline 		Someone told me that if you round the LE of landing gear the aerodynamic properties will increase. I.E. the plane will fly faster.
I also just heard that rounding the TE on control surfaces that otherwise, according to plans, just need the edge taken off will cause flutter at high speeds. Credence to any of this?

Jeff
       Post #: 1

Drag - 2/27/2002 12:36:59 AM   
Mike James



Posts: 2431
Joined: 1/19/2002
From: Anchorage, AK, USA
Status: offline 		Rounding the leading edges of your landing gear (I assume you mean sheet metal type) will reduce the drag. Whether you can actually see the difference or not is hard to predict.

About the sharp trailing edges. Ollie can probably answer this more definitively then me. I've done both sharp and dull trailing edges, and can't say that I've noticed a difference. I'm sure it has a big effect on certain types of planes, at certain speeds.


_____________________________

Mike James
RC Design and Building - www.nextcraft.com

(in reply to Jazzy)
       Post #: 2

Flutter - 2/27/2002 2:53:41 AM   
Ollie


 

Posts: 958
Joined: 12/8/2001
From: Punta Gorda, FL
Status: offline 		Every control surface and its associated linkages has a natural frequency of vibration. The stiffer and lighter the system, the higher the frequency. When aerodynamic forces produce deflection that also is periodic, the stage is set for flutter. Blunt trailing edges and rounded trailing edges can produce vortex shedding. The frequency of vortex shedding is a function of airspeed. When the natural frequency of vibration of the mechanical system matches the natural frequency of vortex shedding, flutter results. There are other, more common aeroelastic, causes of flutter too.

Use sharp, gradually tapered trailing edges to minimize vortex shedding and reduce weight. Make the mechanical system as light and stiff as you can. This will generally raise the natural frequency of the mechanical system well above the vortex shedding frequency in models. Mass balancing around the hinge line makes the mechanical system aperiodic. Aerodynamic balance (hinging through the aerodynamic center) minimizes the aerodynamic forces.

< Message edited by Ollie -- Feb 26 2002 9:59PM >

_____________________________

Regards, Ollie

(in reply to Jazzy)
       Post #: 3

Rounding Landing Gear Edges, Etc. - 2/27/2002 9:51:39 AM   
Jazzy



Posts: 1103
Joined: 1/8/2002
From: Erie, PA, USA
Status: offline 		Shoot!
I knew I should have gone further in my college education, (ASME).
I do understand quite well what you are saying and thank you for your insights.

Jeff

(in reply to Jazzy)
       Post #: 4

Page:   [1]
All Forums >> RC Airplanes >> Aerodynamics >> Rounding Landing Gear Edges, Etc.
Page: [1]





Jump to:


Google 



Search | Marketplace | Event Calendar | Local Clubs | Magazine | Product Ratings | New Products | Discussion Forums

Photo Gallery | Member Video Posts | RCU Video Gallery | Instructor Search | Field|Track|Marina Search

Advertisers | Hobby Vendor Resources | Rate Manufacturers | Sign In/Sign Up

SITE MAP!   : :   FORUM RULES

© 2001 - 2007 24-7 RC, LLC, all rights reserved.

Charities we support that also need your help
Yorkie Rescue | Humane Society | ASPCA | Crohn's-Colitis America

Kaango.com Classifieds

0.314RCU1