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Old 29th October 2009 | 16:56
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seilfly
 
Joined: Nov 2005
Posts: 51
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From: Norway
Well.. technically you are mechanically governing the tension of a spring in the governor, against which the centrifugal forces of the flyweights have to work. The more tension on that spring, the more RPM you are demanding since higher RPM gives more centrifugal force to work against that spring.

So if you demand more RPM by increasing the tension of that spring by advancing your prop levers to full forward, the tension becomes higher. At that point the RPM is lower, and the springtension overcomes the current centrifugal force which allows the pilot-valve to move and give way to the hydraulic fluid (oil) into the propeller-dome, which in turn drives the prop towards finer pitch; which in turn gives LESS DRAG, which in turn gives higher RPM - which in turn... gives higher centrifugal force acting on the flyweights until this centrifugal force counters the tension of the spring you initially set.

If that is what you asked for; exactly what you do with your prop levers? You "Govern" the springtension and the governor governs the "RPM" as it seeks to equal the springtension and centrifugal force by adjusting the RPM by adjusting the pitch.

Did I repeat myself 3 times now?

An animation - somewhat interactive: Propeller and Governor Operation

Last edited by seilfly; 29th October 2009 at 17:05. Reason: (1)The need of an illustration... (2) Pilot-valve was the word I was looking for...
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