Presentation : Franck Aguerre
This Excel software allows effective and quick pre-demensionnig of an
R/C airplane or glider, and gives a realistic estimate of its overall
PredimRc compute also the best settings for the model, to avoid the
very classic crash due to inadapted center of gravity. In this way,
PredimRc can be very helpfull to verify the settings of model built
from a kit or a plan.
The only knowledge required is minimal aerodynamic concepts. PredimRc
is very simple et didactic, so the user can easily understand the influence
of each parameter to the performance or the settings. In order to better
guide the user, most data have comments, often with typical values.
To go further, see the reference site: www.chez.com/aerodynamique, both complete and accessible.
PredimRC is divided into 5 sections (tabs), which follow logically through
the design of the model. Each section is dedicated to a particular point
of the conception process :
- Airfoils : a data base of 9 generic airfoil is provided, extensible
to 36 airfoils
- Aspect ratio : choice and optimization for high performance aircraft
- Overall geometry : drawing of the aircraft, optimization of the lifting
distribution, rating of the performances (sink rate, lift-to-drag ratio),
et above all precise calculation of the center of gravity and angles
- Motorization : calculation of the power equilibrium in flat path,
and estimation of the climbing rate
- Servos : calculation of torque for all classical controls and pendular
elevator, and optimization of pitcheron system
Lexicons data handled:
Input to enter:
- Wing geometry
- 3 wing polar airfoils
- CM0 and Alpha0 profiles
- Stabilisator geometry
- Fuselage geometry
- Cz stabilized flight
- Data engine
- Stabilisator CM0 = 0, ie the center of thrust
at 25% of the average stabilisator chord
- Gradient of the curve Cz = f (impact profile), set to
1 / 11
- 3 stabilisator generic airfoils
- Data bases (scope, size, wing loading)
- Elongations calculated / optimized
- Curves of distribution of Cz and lift VLM
- Calculated center / rear
- Timing of the wing
- Setting of stab
- Volume of stab
- Margin of stability
- Performance curves according to flight speed:
~ Polar speeds
~ Power consumption / power (intersection
= speed of flight)
~ Curve Cz / airspeed
- Flight data engine (autonomy, speed climb, ...)
improved, here is the latest version of PredimRC (translated
in english by Florent Violain, many thanks to him !)
What new :
- Improved interface
- COG calculation and AOI improved
- Polars interpolation tools separated
from the main application
- Addition of generics airfoils
(micro, trainer, multipurpose, quick, flying wing, aerobatic,
racer/F3F/F3B/60 with or without flaps)
- Additon of a customizable airfoil
The guide (V2.1) does
not change at this time because the features are the same to
that provided by previous releases.
The guide does not change
at this time because the features are essentially identical,
the guide to 2.1 is sufficient to find them.
To download PredimRC V2.22 that
works with Excel, click the button.
And below, the very explicit user guide in PDF version 2.1.
(2.1 MB compressed)
Uncompressed version here here
(2.7 MB, in french)
If you follow the regular updates of this site, you
Franck touch regularly for its further development.
The latest version of the program updated date from
June 3 2009
(Check if this version you ...)
- To Raphael Gougnot for its magnificent site and
indispensable "The encyclopaedia of small aerodynamicists
grass" (see link above).
- To Mathieu Scherrer and Thierry Platon for their publications
on the center of gravity and taking into account the issue
of wing wake.
- A John Hazel for the adaptation of the method Excel VLM.
- Many thanks to Dam's, Xav and Nono for their valuable contribution
in the guide PredimRC.
- To Laurent Berlivet, for his enthusiasm still intact despite
the galleys, and of course for the release of this software
in jivaros-models. (Note for the webmaster: I'm the one who
thanks you for your faithfulness and your generosity. It's
always a pleasure to share these pages, and more if they are
beneficial to others.)
- To all those who appreciate this tool ...
Contact the author: firstname.lastname@example.org