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Old 04-19-2004 | 04:12 PM
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Default CG Question

Bought a used Eagle 2 trainer off of a friend for a little of nothing. Plane hasn't been flown for a while, so I'm taking my time checking it out and getting it ready. Replaced the batteries and the fuel tank. Has a KB .40 engine on it and I'm about ready to fire that up. My question is, since replacing the batteries which are a little different configuration and moving things around a little inside, any clue where the CG should be. On my Alpha, it's about 2 3/4" back of the leading edge. The planes are about the same size, I'm thinking the CG would be about the same.

Any thoughts?
Thanks
Stan

This really was a good deal, got 2 Futaba 4 Channels TX's , and a complete RX and servo kit to match up the other TX, plus all of his old ( Still practically new) accessories.
Old 04-19-2004 | 05:20 PM
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Default RE: CG Question

Stan,
My thoughts are the same as yours. It will be fine.

Tom
Old 04-19-2004 | 09:43 PM
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Default RE: CG Question

It will be fine.
Probably, but you can't say that for sure.

A good rule of thumb for a trainer is 25% of the wing's chord, at the root (Where the wing meets the fuse). That will be a safe place to start.

But the "true" starting point for any wing's CG is 25% of the Mean Aerodynamic Chord (MAC), and if you want to know how to calculate that for any wing, here ya' go.
Dennis-
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Old 04-19-2004 | 11:34 PM
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Default RE: CG Question

I think with the Eagle 2, the balance point is on the spar...say 4 inches back from the leading edge can't get at my plans at the moment... ooops gotta go.. 3rd period just started!
Old 04-21-2004 | 01:30 AM
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Default RE: CG Question

Fingers underneath main spar, should be a tad nose heavy with NO fuel-
Old 04-21-2004 | 09:40 AM
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Default RE: CG Question

Thanks guys, I appreciate all of the input.

Stan

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