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Old 03-28-2011, 09:40 AM
trib trib is offline
 
Join Date: Aug 2005
Location: Virginia Beach, VA
Posts: 474
Question Weight/balance calculation question

We plan on making a set of scales available at a flyin. For my 6A, I have to elevate the rear wheels 5" to level the plane. I looking to see if anyone has a spreadsheet or set of calculations that enable measuring weight at each wheel in the configuration sitting on the ground and converting that to the level condition. This would simplify our expect use.

thanks!
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Old 03-28-2011, 06:19 PM
David Paule David Paule is offline
 
Join Date: Dec 2009
Location: Boulder, CO
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That doesn't provide information about the height of the center of gravity, which you'd need to make the conversion.

The height is a second variable (longitudinal center of gravity position is the first) and for that you'd need a second weighing at a different angle. Given that complexity you might as well level the plane and do it by the traditional method.

Dave
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Old 03-28-2011, 07:28 PM
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Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
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I can offer as an alternate method (which may make it a bit easier) but no guarantees:

1) Weight the aircraft in the non level position and calculate gross weight.
2) Remove the nose scale (this will lower the nose the height of the scales).
3) Adjust MLG height (still on the scales) or lower the NLG (tire air?) as necessary to level aircraft and record MLG weights.
4) Calculate NLG weight (Step 1 minus Step 3)
5) Calculate CG from Step 3 MLG weight and Step 4 calculated NLG weight.

Not sure its much easier than leveling on the scales but now you should only have to raise the MLG 2-3 inches instead of 5 (based on the height of your scales). Have fun
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Last edited by Walt : 03-28-2011 at 07:41 PM.
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