So, refreshing this topic. I see on the S-18 plans that the only return spring for the inner flaps is on the 631A drawing for the flap cable installation inside the fuselage. The aft inner rib drawing 200 shows not flap return spring installed. I have these springs installed in my fuse that attach to the flap control arm per 631A, but I am seeing pictures (attached, and as Bob suggests) of inner flap return spring installed on the inner wing/outer rib installed (see pics).
Is my assumption correct that there is only one spring in the fuse on the S-18 drawings (631A) that is needed? Is there a reason or advantage to install inner wing flap return springs in on the outer most rib OR having it installed as well as the inner rib of the outer wing? Drawings 631C shows the outer wing/inner rib with the spring mount installed on the rib. If you elect to install a spring on the outer rib of the inner wing (as show in pics) and you install one on the outer wing inner rib as shown in the plans (631C) will they interfere? Too much spring tension? Assume two are overkill and not needed?
Some insight and expertise welcome.
Rob
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