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Old 26th May 2010 | 16:43
  #51 (permalink)  
Big Pistons Forever
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Veteran: Canadian Forces
 
Joined: Jan 2004
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From: Canada
Originally Posted by Mark1234
Pull what -

I'm personally pondering how you detect a loss of power with a CS prop - other than shaking, banging, or dramatic loss of power, likely to be quite insidious..
For turbocharged engines it is easy, you should get full red line Manifold Pressure (MP) on every takeoff. Any less is grounds for an immediate reject.

For non turbocharged engines you should get about 1/2 inch less than field barometric MP on takeoff (field baro is what the MP guage reads when the engine is not running).

Obviously in both cases you would also check that you have full redline RPM as well.

On a related topic one area that does not IMO often get the attention it deserves is noting the fuel flow on takeoff in aircraft with fuel injected engines. All light aircraft engines depend on excess fuel flow to help cool the cylinders at full power. The fuel flow should be right at the redline maximum value (or even a little bit over) at full power. If it is even a little bit low it should adjusted by an engineer. Prolonged operation without suficent fuel flow will damage the cylinders.
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