Par file Applet - What The FMS world needs.

[Mr P Trog]

What we need is an applet (read wizzard) that will ask you all the pertnate stuff about your model and spit out a par file that matches it.
Any one have the skill and time to crank one out?

Till then I will take a link to a good complete explaination of all the strings in a par file.

[Chris Stoddart]

The recently released free addin to RcCad reads the geometry from the .RCD file and writes the calculated .PAR parameters into the .MDL file. It also writes a text file of these parameters for other uses.

The addin has even worked with a delta wing with elevons. The estimated CG was a little far back, thrust a little low and elevon movement too conservative but after editing these parameters with the built in editor the delta 'flew' pretty well.

Happy Landings,
Chris Stoddart

[nadisha]

Well visit my site
www.sumuthu.lk/fms
and see the RCD designer works for you?

Good luck...

[mandobassman]

[mandobassman]

I'm really beginning to get frustrated with these designer programs. I have RcCAD 1.7.1 and have created a model with it. Now I can't find a version of FMS Converter that will convert the model for me. The latest download of FMS Converter requires a model created in RcCAD 2.0. I tried downloading the trial version of RcCAD 2.0 and recreating the model then converting it but I get a model with no image. It flies but like another post I've seen elswhere in this forum, you can't land an invisible plane!. Does anybody know where I can find an older version of FMS Converter? I have also tried METASO******* but the program is really awkward to use (i use AutoCAD 2000i on a daily basis at work). Any suggestions as to how I can make my model visible?
We really do need a good applet that will take the parameters of your proposed model and apply them to a model that can be taken into FMS and flown (or not if the model just isn't capable of flight). This could be a great test bed for model builders without the expense of the model.

[Chris Stoddart]

Hi Ken,

I am the author of the RcCad to FMS applet. I will be pleased to help you use it. I will also work on the problem of backward compatibility with RcCad 1.7.1 .RCD files.

Please send me the .RCD file as an email attachment and I will send you back a working .MDL file along with the explanation of what I did to get it working.

Have you tired to zoom in on your model? The applet assumes that the model is created and saved in units of millimeters, this is stated in the applet Help file. The applet divides all dimensions by 1000 to produce a model file with units of meters. An RcCad design of typical model airplane size that is saved in the units of inches will appear quite small on the FMS runway.

I look forward to helping you.

Happy Landings,
Chris Stoddart

[mandobassman]

Hi Chris,
Thanks for the quick response. I am writing this from work so I don't have the model file with me. I have since worked my way up the learning curve for Metasequoia and I am able to work with it to a certain degree. However I have not completed a model yet with materials attached. I still like the looks of RcCAD though. A little more info on RcCAD would be helpful though. Does FMS converter apply actual flight characteristics to the model as deduced from the size shape and configuration of the model as built in RcCAD? In other words am I getting a delta wing jet that will fly with a set of parameters similar to a Cessna? Also, I couldn't find an option for specifying power units or component weights. Is this available in RcCAD or do I need a more robust modeling program?

Thanks again for the quick response.
Ken

[Chris Stoddart]

Ken asked about the RcCad to FMS applet calculation of Flight performance parameters.

The RcCad to FMS applet calculates the Flight Performance parameters based on the geometry in the RcCad .RCD file. I have incorporated a number of approximations, rules of thumb, etc. taken from Model Airplane magazines, NACA reports, and other sources. For example the model mass is established based on the area of the first RcCad wing and a typical wing loading factor. The engine thrust is established as a function of the model mass. The pitch moment of inertia is established as a function of model mass and the square of the distance between the wing and the stab. There are many other parameters to be calculated. In general I have tried to approximate the flight performance of a typical sport/trainer model.

All the Flight Performance Parameters may be edited (changed form the calculated values) with the Flight Performance tabs that can be opened within the applet or by editing first section of the .MDL file.

Happy Landings,
Chris Stoddart

[johnhlong]

I haven't looked at RC-Cad lately but when I did a while back it didn't look like it supported Helicopters.

Have I missed something?

John Long
Seattle, Wa.
USA

[Chris Stoddart]

RcCad may be used to model most any aviation geometry. There are many helicopters in the gallery at www.rccad.com .

The RcCad .RCD to FMS .MDL applet is written for conventional designs and does not determine the Flight performance parameters needed for helicopters.

Happy Landings,
Chris Stoddart