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Old 1st Dec 2001, 19:44
  #56 (permalink)  
Lu Zuckerman

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Join Date: Sep 2000
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Question

To: All

I guess low lifes' and uneducated individuals like myself and this includes many mechanics and some pilots will just have to go through life believing that the blades have centrifugal force acting on them, which balances out the lift on the blades and keeps the blades in almost radial alignment. Since this is what we were taught in tech school with the aids of comic book texts with illustrations that do not relate to those used in engineering texts we just keep believing.

It is difficult to understand, using a CH-37 as an example that the rotorhead must exert 72,000 pounds of measurable force to accelerate a blade in a circle. Is there that much drag and is there that much inertia. Also what makes the blade fly in an almost radial position relative to the center of the rotorhead? What keeps it in alignment if there is no centrifugal force? It is also difficult to understand how a blade that is being dragged through a circular path will not flap up to an extreme if there is no force to balance out the lifting forces. If centripetal force is pulling the blade inward how does this force transmit to the blade to balance the lifting forces and keep the blade in radial alignment (almost) if the blade is isolated from a linear inward pull by the flapping hinge and the lead lag hinge? What force does in actuality allow the blade to fly in an almost radial position and to balance out the lifting forces? Could it be CENTRIFUGAL?
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