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Finding c/g on wing

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Old 04-15-2014, 05:15 AM
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earl267
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Default Finding c/g on wing

Hi Guys. I purchased a 1/4 scale plane it is called a rainbow looks a lot like a piper cub, I flew it the other day and it seemed a little tail heavy. I would like to balance it to see but don't have any plane to tell me where the c/g is. I looked at other plans I have and it is a little then one third of the wing. My wing is 16 1/2 wide and 100 long can any one tell me what it should be to get the right c/g. ? Thanks Earl Peak. there is a photo in my gallery.

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Old 04-21-2014, 01:55 PM
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This method works very well for me on my giant scale planes.
Good luck.
http://home.mindspring.com/~the-plum...%20Machine.htm
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Old 04-27-2014, 10:29 PM
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JohnBuckner
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[QUOTE=earl267;11783332], I flew it the other day and it seemed a little tail heavy. I would like to balance it to see but don't have any plane to tell me where the c/g is. I looked at other plans I have and it is a little then one third of the wing. My wing is 16 1/2 wide
QUOTE]

The Vanessa rig that panhandler linked to is a good method to find the actual existing CG however you seem to be asking where is a good target CG that will help your airplane fly better. The answer to that that with a straight cord wing like that is not 1/3 that is to far to the rear.

Try adjusting the current CG forward to 1/4 chord. Many airplanes that is often where the spar is but not all so the simple solution with your airplane is to divide that 16 1/2 inch chord by four and that is how far back from the leading edge you will want to have the airplane to balance at.

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Old 04-28-2014, 11:30 AM
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earl267
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Thanks guys that looks like a sure thing, I am going to try it. Thanks earl267.
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