I've been flying for over 20 years and I don't believe I've ever had a flight where a engine HASN'T picked UP idle RPM's at the end of a flight. Glows are worse than gas. I just always chocked it up to the engine leaning out because of lower fuel level, engine getting warmer, etc. etc. This is why I fly with a JR radio with a rachett throttle trim. It's just something I do when I'm landing is pull back 3 or 4 clicks on the trim and "come on down".
If there is someway to prevent this I've never figured it out [
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