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2 Answers

Manifold pressure guage

Asked by: 3548 views Aircraft Systems, Commercial Pilot, Flight Instructor

In an aircraft with controllable pitch prop the manifold pressure guage will indicate ambient pressure when the engine is turned off. But what if it reads a value of lets say 10" MP. What could be the problem ? Why would this happen ?

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2 Answers



  1. Bob Watson on Mar 17, 2014

    If the gauge is accurate and the engine is off, it could be the airplane is at 26,000′ (where the ambient pressure is about 10″). If the plane is not at 26,000′ and the engine is off, I’d check for a problem with the gauge.

    Did this happen to you or are you just wondering?

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