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Old Dec 27, 2003, 11:43 PM
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in persuit of low wing loading
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Boston, Mass
Joined May 2001
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The arms in the "L" do not need to be the same length. I they are not you simply multiply the force measured by the ratio of the lengths of the arms.

I really don't think it matters which design you use, strain, connected with a string, "L-arm", etc. In most cases the conclusions we draw will not be tremendously affected by a small error in the measurment of grams of thrust. My first thrust stand was made from Tinker Toys and gave results almost identical to my current ball bearing pivoting stand.

In the case of motor development, the static thrust developed is an incidental by product. We are simply putting a load on the motor. Along the way we get some idea how much thrust we might reasonably expect. But, if we really want to know and optimize thrust, that's more a question about the prop and then a wind tunnel is the appropriate place to test.

Gordon
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