If, disadvantageously, this angle were to be made less than 90°, then when the wing 22 encountered a fiber 11 lying along {HEAD ~ a wall} of the V groove 14, a component of {TAIL ~ the force} exerted on the fiber 11 by the wing 22 would be directed into the wall 
If , disadvantageously , this angle were to be made less than 90 ° , then when the wing 22 encountered a fiber 11 lying along { HEAD ~ a wall } of the V groove 14 , a component of { TAIL ~ the force } exerted on the fiber 11 by the wing 22 would be directed into the wall
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