Minn: (And others)

I have to stick my nose in here.

With a trainer or sport single, holding the engine revs down, you can be satisfied with "Close" balance and get away with it. But the imbalance still adds needless vibration, and the plane will last longer if it is eliminated. At higher engine speeds the vibration frequency goes up, and its intensity also. Shakes things apart faster. Any vibration you can eliminate is worth the trouble.

When you get into twins it's even more important - with two engines the vibrations can be additive and really damage radios, break wires, hammer teeth off servo gears, all sorts of little minor irritations. But they usually lead to destruction of the plane. That's NOT a minor irritation.

Since no reasonable person expects his trainer to last more than a year or two, vibration from a reasonably close prop balance job isn't going to hurt. But when you go from $400 planes to $1200 and more each you might want to take more care with props.

I have several planes more than 20 years old, still in good condition. I don't blame it all on prop balance, of course. Maintenance inspections are very important, and we can not forget my unmatched piloting skills. Haw.

And Haw again.

Have to admit the last plane I destroyed was about 4 months old, and its destruction was entirely due to my piloting skills.

Prop be a shaker?
. Good plane breaker.

Bill.