Dancing aircraft

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Dancing aircraft

Postby NCGent » Thu Oct 19, 2006 9:02 pm

Hey guys, I just finished a project, got the model built, flight dynamics writen, panel made, but when I load the aircraft the bird dances around a little, little hops. It will stop at times and other times it keeps hoping. And it sometimes hops around on takeoff. If I turn the engine off, it quits. Any ideas what is going on and how to stop it?

Thanks
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Re: Dancing aircraft

Postby Brett_Henderson » Thu Oct 19, 2006 11:07 pm

Contact points, static height and damping ratio..

I'd say more, but I'd have to have the plane to examine..
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Re: Dancing aircraft

Postby pete » Fri Oct 20, 2006 4:08 am

This used to be an .air file problem. With so much modifiable within the aircraft.cfg it's hard to tell.

Try adding an appropriate .air file from another a/c to see if that helps.
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Re: Dancing aircraft

Postby Katahu » Fri Oct 20, 2006 11:39 am

My guess is that your compression ratio is off. Remember that you can't just simply punch in any number for the ratio. You have to calculate it first before input it into your aircraft.cfg file.

For this calculation, we shall use the bottom of each landing gear tire as the point of reference for the following steps:

1 - Determine the distance between the gear's fully extended position and its semi-compressed position when the aircraft rests on the ground.

2 - Determine the distance between the gear's fully compressed position and its fully extended position.

3 - Determine the ratio by dividing the distance you found on step 2 by the distance you found on step 1.

At this point your have your ratio which is simply a decimal value [ie: 3.112].

The dampening ratio can sometimes contribute to the problem as well. The value for the ratio can be any number ranging from 0 to 1 [ie: 0.117, 0.576, etc.]. The higher the value, the more the dampening effect.
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