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YASim Guide

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YASim Guide

Postby Buckaroo » Thu Oct 10, 2013 5:19 am

Howdy,

Over the last few years of serious tinkering with YASim, I've collected a volume of notes related to my experiences and findings. I've finally finished assembling these into something that is more-or-less readable. It's not quite complete, notably it's missing a section on landing gear and turboprops. But I think it's now worth a look, especially for those relatively new to YASim.

http://www.buckarooshangar.com/flightgear/yasimtut.html

Regrettably the guide does not include sections on rotary-wing aircraft. I try to write only about things I have first-hand experience with, and I've yet to work with YASim helicopters. My apologies to all the helicopter fans out there.

Constructive comments, suggestions, and other feedback are always welcome.

-Buck
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Re: YASim Guide

Postby Johan G » Thu Oct 10, 2013 8:50 am

Updated the link on the YASim wiki page so it now point directly to your guide. :)

EDIT: Also mentioned it in the upcoming newsletter.
Low-level flying — It's all fun and games till someone looses an engine. (Paraphrased from a YouTube video)
Improving the Dassault Mirage F1 (Wiki, Forum, GitLab. Work in slow progress)
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Re: YASim Guide

Postby x7cusick8x » Thu Oct 10, 2013 12:31 pm

I'm still trying to figure out helicopters fuel systems for my SH-60 and HH-60 with the Yasim fdm
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Re: YASim Guide

Postby Buckaroo » Mon Oct 21, 2013 3:37 am

Johan G wrote in Thu Oct 10, 2013 8:50 am:Updated the link on the YASim wiki page so it now point directly to your guide. :)

EDIT: Also mentioned it in the upcoming newsletter.


That's great Johan, thank you!

-Buck
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Re: YASim Guide

Postby Johan G » Fri Oct 25, 2013 10:44 am

You are very welcome! :D
Low-level flying — It's all fun and games till someone looses an engine. (Paraphrased from a YouTube video)
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Re: YASim Guide

Postby Buckaroo » Fri Dec 06, 2013 11:29 pm

Just a heads-up that the manual now contains a section covering the basics of YASim turboprop engines.

Still working on the landing gear/ground interactions section.

-Buck
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Re: YASim Guide

Postby zlsa » Fri Aug 29, 2014 3:56 am

Just commenting to say that your guide helped me start designing YASim FDMs and therefore FlightGear aircraft. I've moved on to JSBSim now for its flexibility but without your YASim guide I probably wouldn't have gotten started. Thanks.
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Re: YASim Guide

Postby Tomaskom » Fri Aug 29, 2014 7:07 am

zlsa wrote in Fri Aug 29, 2014 3:56 am:Just commenting to say that your guide helped me start designing YASim FDMs and therefore FlightGear aircraft. I've moved on to JSBSim now for its flexibility but without your YASim guide I probably wouldn't have gotten started. Thanks.

Exactly the same for me :)
The very first step for me was reading your guide, after doing so I had a very good idea about how YASim works. If I started by studying existing aircraft, I would be probably left with a heap of bad practices stuck in my head :roll: .
Reading the YASim source code didn't help me much (even though I'm a C++ programmer), yes, I got a few bits from there, but it is not the best way to get the general picture of how things are working.
I don't think I'll be moving over to JSBsim anytime soon, as the results I'm getting from YASim seem more than good enough.

Again, big thanks to you for giving me (and many others) an easier headstart in FDM development :)
"There are no problems in the air. The only problem is hitting the ground"

Get my L-159 ALCA from the FGUK hangar. If you crash it, things gonna go boom!
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Re: YASim Guide

Postby Buckaroo » Sun Sep 07, 2014 3:36 am

I'm very happy to learn that the YASim guide has been useful to some folks in some way. I found the process of learning YASim and writing the guide to be instructive, not just for the FDM, but for aerodynamics in general. In some ways, this was the ironic "gift" of YASim's horribly poor documentation-- I had to learn a lot to figure out what YASim was supposed to be doing, and what values are reasonable for all those gazillions of attributes. It was an interesting journey.

Cheers!
-Buck
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Re: YASim Guide

Postby helijah » Thu Nov 27, 2014 7:10 pm

Hey Gary,

I join to Tomaskom for congratulate you. I give very often link to your Guide that remains, to this day, the only real reference to create a FDM worthy of the name.

Then thank you :)

Regards Emmanuel
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Re: YASim Guide

Postby Buckaroo » Tue Dec 02, 2014 2:32 am

helijah wrote in Thu Nov 27, 2014 7:10 pm:Hey Gary,

I join to Tomaskom for congratulate you. I give very often link to your Guide that remains, to this day, the only real reference to create a FDM worthy of the name.

Then thank you :)

Regards Emmanuel



Merci, c'est gentil de votre part.

I wish I had more time (and a much better computer) to keep up with the ever-changing Flightgear. There's much more I could and should do. I have an interest in maintaining YASim, but haven't been able to invest time into learning all that is necessary. I keep expecting someone better qualified will take on the maintainer role...

-Buck
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Re: YASim Guide

Postby MountainFlyerN22 » Sun Dec 14, 2014 1:14 am

Such a big help to me.Just waiting for the landing gear section :)
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Re: YASim Guide

Postby Buckaroo » Tue May 12, 2015 2:12 am

MountainFlyerN22 wrote in Sun Dec 14, 2014 1:14 am:Such a big help to me.Just waiting for the landing gear section :)


I finally got around to proofing and HTMLizing that section. It's no longer a gaping hole in the guide. Hope it helps someone.
-Buck
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Re: YASim Guide

Postby Jabberwocky » Wed May 13, 2015 6:10 pm

Wow, I love it! Thanks Buckaroo
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Re: YASim Guide

Postby massima » Wed May 13, 2015 7:43 pm

I've just finished to read your guide, you explain YASim FDM in a simple way, thank you.
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