The weight and balance section of the RV-10 plans says "... the airplane should be weighed in the empty condition and in a level attitude..Use plumb lines or vertical levels to measure the locations of the main wheels relative to the wing leading edge, and then covert this to an arm relative to datum.".
With the longeron at the door opening level (rear wheels elevated a bit), I found that the mains were 123.8" and 123.5" aft of datum, and my nose wheel was 49.5" aft of datum. Van's weight and balance example shows the mains at 124.4" and 124.3" aft of datum, and the nose at 50.4" aft of datum. So my measurements showed my wheels being .7" to .9" further forward than Van's.
This large a difference surprises me, and leaves me a little concerned about the potential that my actual CG might be .7" to .9" further aft than my calculations show. I'm interested in learning what others found when you made the datum measurements on your finished planes.
With the longeron at the door opening level (rear wheels elevated a bit), I found that the mains were 123.8" and 123.5" aft of datum, and my nose wheel was 49.5" aft of datum. Van's weight and balance example shows the mains at 124.4" and 124.3" aft of datum, and the nose at 50.4" aft of datum. So my measurements showed my wheels being .7" to .9" further forward than Van's.
This large a difference surprises me, and leaves me a little concerned about the potential that my actual CG might be .7" to .9" further aft than my calculations show. I'm interested in learning what others found when you made the datum measurements on your finished planes.
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