[SOLVED] P-51 : No MP rise with RPM reduction bellow 41" ?

[Guest deleted@50488]

I noticed that no matter at what altitude I increase or decrease RPM when MP at or bellow 41", there will be no tendency for it to move opposite of RPM.

 

For instance on ground, with MP at, say, 30", RPM reduction should increase MP and the way around.

 

This is due to the blower kicking in above a given MP ( usually 41" ).

 

[SOLVED(?)]: Either I was not looking with sharp eye or something changed in an interim update, but today I was able to test this effect at a very low MP setting while doing engine tests on ground.

Bellow  around 13" MP the RPM regulations affect MP in the opposite way - incease RPM, MP drops and the way around. It's a slight variation, but it's there.

 

Probably the blower in the modeled P51 kicks in a lot lower then in more modern models?

Edited October 14, 2019 by jcomm-il2
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