Tail rigging wire locations

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PoconoJohn
Posts: 165
Joined: Tue Jan 14, 2020 9:07 pm

Tail rigging wire locations

Post by PoconoJohn »

The plans indicate the center of the rigging brackets on the horizontal stabilizer are located 34" from center. I was just wondering if there's a particular aerodynamic or structural reason for that location (how or why did Bernie choose it). Same thing for the vertical stabilizer location. Thanks!

John C
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taildrags
Posts: 637
Joined: Tue Mar 07, 2017 10:39 pm

Re: Tail rigging wire locations

Post by taildrags »

I just looked at my plans and I see what you mean. About the only reason I can think of is that the brace wire anchor points end up about as far out on the stabilizer spars as practical without getting into gussets and hinges, and if the wires are run clear out to the ends the angle of the brace wires is reduced which means more tension on the wires for the same forces on the stabilizer surfaces. Ideally, the stabilizers would be supported at both ends so the bending stresses would be minimal, but that last 11 inches or so that is cantilevered outboard past the brace wire anchor points isn't a lot of surface to be bending. I would say that moving the anchor points an inch or two inboard or outboard wouldn't change much, but outboard would be better. I thought maybe the proportions had something to do with it, and it does turn out that 34" is about 3/4ths of the total stabilizer span of 45" but I think that's just the way it turned out. Opinions will probably vary ;o)

-Oscar
PoconoJohn
Posts: 165
Joined: Tue Jan 14, 2020 9:07 pm

Re: Tail rigging wire locations

Post by PoconoJohn »

Thanks Oscar.

John
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