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