Thank you guys, it was the prop pitch that did it. I am fairly new to the sim, so I havent tried the complex engines settings yet - but when i did, the rpms stayed solid.
And thanks to Luthier for COD! I have flown sims since "the knights of the skies", on Amiga back in 1992 (or 3), and I think this one is the toughest of them all! I simply enjoy it.
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