RE: Graupner Vs APC prop observations  
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
       


90 Degree Muffler Adapter
Seller:  RC Specialties
Details:   $17.95   |  7/13/2008   |  Classified Ad
We will rotate YOUR AD in this spot if you select "Forum Featured" when placing or editing your ad!

All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Glow Engines >> RE: Graupner Vs APC prop observations
Page: <<   < prev  1 [2]

Login
Message << Older Topic   Newer Topic >>
RE: Graupner Vs APC prop observations - 5/17/2008 2:43:41 PM   
Daryl Martel



Posts: 595
Joined: 2/10/2002
From: WinnipegManitoba, CANADA
Status: offline
Ohhh - I should have added... noise is a great measure of efficiency. Quieter props are losing less energy to the production of noise. The thin tips create less tip vortex - again less loss of energy. The more energy that is transferred directly to producing thrust the better. Energy loss is next to moot in our glow/gas RC planes, but much more important in electrics were it's more dearly felt.

_____________________________

Spending my daughters inheritance one plane at a time...

(in reply to blw)
       Post #: 26

RE: Graupner Vs APC prop observations - 5/17/2008 2:49:13 PM   
blw



Posts: 4457
Joined: 3/15/2004
From: Auburn, AL, USA
Status: offline

quote:

ORIGINAL: Daryl Martel

The thin tips create less tip vortex - again less loss of energy.



Not always. Shape is important. An elliptical shape probably contributes less vortices. Blunt, squared off tips such as Master Airscrew and Zinger props are very dirty, and inefficient at most speeds compared to other designs.

_____________________________

The ultimate responsibility of pilots is to fulfill the dreams of the countless millions who can only stare skyward...and wish.

(in reply to Daryl Martel)
       Post #: 27

RE: Graupner Vs APC prop observations - 5/17/2008 2:58:03 PM   
Daryl Martel



Posts: 595
Joined: 2/10/2002
From: WinnipegManitoba, CANADA
Status: offline
To a point (pun intended) as the high taper permits thinness to be designed in. I agree with you. Didn't think it neccessary to elaborate on that (that's why I mentioned APC, Bolly & Mezlik - all similar shape). A long chord, but thin tip is more like a sheet of paper isn't it! Not much strength (so it'll easily twist) and produces thrust more by deflection than aerodynamic force.

< Message edited by Daryl Martel -- 5/18/2008 12:15:01 PM >


_____________________________

Spending my daughters inheritance one plane at a time...

(in reply to blw)
       Post #: 28

Page:   <<   < prev  1 [2]
All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Glow Engines >> RE: Graupner Vs APC prop observations
Page: <<   < prev  1 [2]





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


0.281RCU1