Is a STATIC Prop Balance Enough?

Your prop was statically balanced at the factory and that's good enough?

A static balance may balance the prop but it does not correct the net imbalance of the rotating assembly.

This is a relatively new, statically balanced prop on a Cessna 210. The first "statically balanced" reading was 0.6 IPS, which is pretty typical. It took 10 large washers (mind the reflection which makes it look like 20) on the spinner to pull it into balance (0.06 IPS).

This may look like a lot of weight, but the rotational forces are now neutral! Before the prop was dynamically balanced, this is the amount of weight was constantly shaking the airplane and stressing every part of the engine and airframe. That's a LOT of stress at 2000+ RPM!!!

The point is that a prop static balance is not enough.  The static balance gets the balance in the ball park but you really need to balance the entire assembly.  Not just the prop.  The latest data that we have been analyzing shows that around 80% of all GA aircraft are flying with imbalanced props even though most were statically balanced.