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Why do FG helos ALWAYS yaw?

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Why do FG helos ALWAYS yaw?

Postby sgofferj » Wed Jan 04, 2012 4:12 pm


as I am mainly a helo person, I started noticing that helos in FG ALWAYS yaw. Some - like the OH-1 even with parking brake set, some, like the Huey, even with engine shut off.
Ok, we know there is torque and anti-torque. But there also is something like ground friction and then shut-off engines? :lol:

I'd be curious to know where this comes from and especially - I am wondering a bit - that *seems* to be a rather small problem and considering all the cool and probably very complicated stuff in FG, like clouds, weather, water reflections, etc., I wonder why it even exists...
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Re: Why do FG helos ALWAYS yaw?

Postby Gijs » Wed Jan 04, 2012 4:27 pm

It exists since long... :(
Something to do with YASim. See our bug tracker: ... ail?id=155
You could "start" the issue, to increase visibility...
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Re: Why do FG helos ALWAYS yaw?

Postby HHS » Wed Jan 04, 2012 4:35 pm

There are some more people who would like to know it. It is a long known bug and, at least for me as a helo person as well, a critical bug ....;-)

See here for more details: ... 0Milestone

What I find out so far is that an intelligent distribution of the ballast will prevent from sliding/yawing, like you can see on the BO105, EC135, EC130, ....

The Bell UH1 can be easily "fixed":
change friction on all gears to : sfric="0.5" ; dfric="0.4"
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Re: Why do FG helos ALWAYS yaw?

Postby someguy » Thu Jan 05, 2012 4:44 am

Thanks for the Huey numbers, Heiko. They work like a charm.
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