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Will the cg change just by clipping the wing that rectangular.

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Will the cg change just by clipping the wing that rectangular.

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Old 06-01-2018, 04:09 PM
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suzonka
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Default Will the cg change just by clipping the wing that rectangular.

Hi I have an electric super sport by great planes . its a straight rectangular wing is 48" and I clipped 2 " off each end of the wing and made it squared off like a sig 4 star.
now when I put a battery in it and used the original marking on the wing for the CG its just as though I never clipped the wing , yet Im interested in will it be OK leaving the same CG marks for setting the CG?

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Old 06-01-2018, 05:02 PM
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All Day Dan
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The CG location for model airplanes is primarily determined by the shape of the wing. For a constant chord wing, a safe location is 30% of the chord behind the leading edge. Since you only shortened the wing span you can leave the CG where it was. Dan.
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Old 06-01-2018, 06:51 PM
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Default Cg on a shortened winng

Hi I have an electric super sport by great planes . its a straight rectangular wing is 48" and I clipped 2 " off each end of the wing and made it squared off like a sig 4 star.
now when I put a battery in it and used the original marking on the wing for the CG its just as though I never clipped the wing , yet Im interested in will it be OK leaving the same CG marks for setting the CG? Thanks Dan I was Hoping that would be OK
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Old 06-01-2018, 07:17 PM
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Here's a couple o my models that I used that 30% number. Dan
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Old 06-01-2018, 07:20 PM
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Nice Planes dan keep flying
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Old 06-05-2018, 06:48 AM
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Originally Posted by suzonka View Post
Hi I have an electric super sport by great planes . its a straight rectangular wing is 48" and I clipped 2 " off each end of the wing and made it squared off like a sig 4 star.
now when I put a battery in it and used the original marking on the wing for the CG its just as though I never clipped the wing , yet Im interested in will it be OK leaving the same CG marks for setting the CG?
Hello!
you should not have any problem with the C/G location by shortening a "rectangular" wing, but you will notice other changes, roll rate increase and longer takeoff runs, steeper glide rates, Maybe more speed. Most if not all changes causes some form of trade off some gain and loses, experimenting with these changes is in my opinion one of the best parts of modeling. Happy flying!
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Old 06-10-2018, 05:51 AM
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the static CG will not change, but the dynamic cg may change just a little bit because the dynamic CG includes reaction to drag which has changed from reducing wing area. that said, I very highly doubt you will be able to notice any change in flight characteristics.
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