How do I calculate prop slip for my six pack test?
Richard,
This question concerns the relarionship of the prop''s pitch and its actual travel through the water at any given speed. You need to know this to accurately calculate the hull speed of a vessel at a given engine and therefore the prop''s RPM.
Slip in % = 100 X ( Prop pitch in feet X prop rpm  vessel speed in knots devided by prop pitch in feet X prop rmp )
This is one formula to estimate prop slip, I''m sure there are others.
Good luck. JEF
