SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Jan 13, 2015, 11:02 AM
Registered User
Joined Jul 2014
3 Posts
Mini-HowTo
A Process for Calculating Model Drag - Nicolai

The purpose of this white paper is to present a method on how to estimate the aerodynamics and performance of R/C aircraft models.
jadadad is offline Find More Posts by jadadad
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 19, 2015, 04:05 AM
Registered User
United Kingdom, England, Southampton
Joined Oct 2013
2,317 Posts
Nobody else has commented so I will.

1) There are one or two doubtful assumptions in that report.

2) Toy planes are so uncritical and there are so many variables in actual flying that the calculated results are likely to be nowhere near accurate.

3) Why do so many people (not you, you didn't create the report) waste their time on such stuff? I don't want to 'pick on' anyone so won't name names but you see similar pointless (pointless if they actually fly toy planes, if they don't why are they here?) stuff often in the 'Modelling Science' section. And I'm not 'anti-science', I was near enough a 'scientist' of sorts myself all my working life.
Mark Powell is online now Find More Posts by Mark Powell
Last edited by Mark Powell; Jan 19, 2015 at 04:12 AM.
Reply With Quote
Old Jan 19, 2015, 03:02 PM
Grad student in aeronautics
United States, GA, Atlanta
Joined Oct 2010
479 Posts
I've found that people in the modeling science section are generally interested in the science of flight.
DPATE is online now Find More Posts by DPATE
Reply With Quote
Old Jan 19, 2015, 03:48 PM
Sink stinks
Montag DP's Avatar
United States, GA, Atlanta
Joined Apr 2005
4,580 Posts
Quote:
Originally Posted by Mark Powell
Nobody else has commented so I will.

1) There are one or two doubtful assumptions in that report.

2) Toy planes are so uncritical and there are so many variables in actual flying that the calculated results are likely to be nowhere near accurate.

3) Why do so many people (not you, you didn't create the report) waste their time on such stuff? I don't want to 'pick on' anyone so won't name names but you see similar pointless (pointless if they actually fly toy planes, if they don't why are they here?) stuff often in the 'Modelling Science' section. And I'm not 'anti-science', I was near enough a 'scientist' of sorts myself all my working life.
1) It would be helpful if you pointed them out.

2) The paper is titled "ESTIMATING R/C MODEL AERODYNAMICS AND PERFORMANCE." The word estimate means it's not exact. It's a reasonable approximation based on what is known of the model, scaling laws, and empirical data. Though, some validation cases would definitely be a valuable addition to the paper.

3) Speak for yourself. Just because you don't find it useful doesn't mean it's not useful to someone else. Actually, if you find something to be pointless, there's absolutely no reason for you to mention it at all. Just move on.
Montag DP is offline Find More Posts by Montag DP
Reply With Quote
Old Jan 19, 2015, 08:37 PM
Registered User
richard hanson's Avatar
United States, UT, Salt Lake City
Joined Oct 2007
7,751 Posts
R/C models typically
have wing loadings of 1-3 lb/ft2 whereas the full scale airplanes are greater than 10
(Cessna 172 is 12.6 lb/ft2).
END QUOTE
The article obviously includes a lot of data-
however I noted the comparative info shown here has as it's lower point a value double many performance type low speed models
In fact - a value of 6 OUNCES per square foot is not uncommon.
Noting this, I wondered how well the rest of the info applies to models having these lower loadings
My own ventures into this area show that the performance drops off at a extremely high rate as size in wing loadings around 1-2 ounces is reduced .
being a hands on guy, the lack of published data was not that important but I looked -and I saw none There my be some new work now -
richard hanson is online now Find More Posts by richard hanson
Last edited by richard hanson; Jan 19, 2015 at 08:44 PM.
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Calculate Drag for a Flat Plate Foamy HugePanic Modeling Science 9 Apr 25, 2008 03:12 PM
Discussion Need Some Airfoil Aero Engineer Number Crunching Asistance / Drag Calculation Z06kal Slope 3 Mar 21, 2006 11:07 PM
How do you calculate the drag of a simple object Mat Modeling Science 11 Nov 25, 2004 02:52 AM
How to Calculate AIRCRAFT Lift & Drag Coefficients? green66 Modeling Science 2 Oct 26, 2003 12:37 PM