CG location needed for TW-748-1 Corsair
05-11-2009, 11:56 AM
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CG location needed for TW-748-1 Corsair
I bought this plane from nitroplanes.com as a ARF. It's a nice, sturdy plane, but it was originally designed to be sold as a RTF. There are no instructions of where the CG should be, or which prop size is used. ( I put my own brushless outrunner motor in it and the rest of the electronics.) Any help would be appreciated. Thanks.
05-11-2009, 12:12 PM
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RE: CG location needed for TW-748-1 Corsair
As with most straight wing planes, you want the C.G. to occur at between 25-30% of the MAC.
If you are new to this plane, a 22-24% C.G. is suggested.
If you are new to this plane, a 22-24% C.G. is suggested.
05-11-2009, 12:30 PM
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RE: CG location needed for TW-748-1 Corsair
Ok, however I must admit some ignorance. What does MAC mean? Is it the width of the wing minus the ailerons? also, I assume you mean straight winged does not apply to the way this wing is curved at the fuselage.
05-11-2009, 12:35 PM
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RE: CG location needed for TW-748-1 Corsair
MAC refers to the Mean Average Chord length.
The C.G. should occur about 22-25% back from the leading edge of the wing, as measured straight back along the wing root.
The plane will probably fly with the C.G. occuring all the way back to 30% or more, but it will be twitchy and overly responsive.
Beyond this, the plane will be uncontrollable and incapable of flight.
If you had full with ailerons ( which you do not ), this would INCLUDE the width of the ailerons.
Your plane has a "straight" wing. Meaning that the wing is practically perpendicular to the line described by the fuselage.
The gull wing shape has nothing to do with this, rather the "straight" wing refers to the complete lack of sweep back on the wing.
The C.G. should occur about 22-25% back from the leading edge of the wing, as measured straight back along the wing root.
The plane will probably fly with the C.G. occuring all the way back to 30% or more, but it will be twitchy and overly responsive.
Beyond this, the plane will be uncontrollable and incapable of flight.
If you had full with ailerons ( which you do not ), this would INCLUDE the width of the ailerons.
Your plane has a "straight" wing. Meaning that the wing is practically perpendicular to the line described by the fuselage.
The gull wing shape has nothing to do with this, rather the "straight" wing refers to the complete lack of sweep back on the wing.
05-12-2009, 03:38 PM
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RE: CG location needed for TW-748-1 Corsair
Ok, thanks. I verified this by taking my plane into a local shop. The CG is located about 2 1/2 inches from the wing's leading edge on the support spar. I had to mount the battery a bit forward, but it flies fine now! I used a 3C GWS brushless motor with a GWS EP-9047 prop.
