PIVOT POINT

HEAD WAY, STEADY COURSE & SPEED

AHEAD BELL FROM DIW... LONG STEERING LEVER FROM PROPS/RUDDERS

ASTERN BELL FROM DIW... NO EFFECTIVE STEERING LEVER UNTIL SOME STERN WAY

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REFERENCES: HOOYER, CHAP 1

Notes:

THE SECOND CONCEPT TO KEEP IN MIND IS THE PIVOT POINT. REMEMBER THE PIVOT POINT WILL MOVE ABOUT THE SHIP DEPENDING ON YOUR ORDERED ENGINES. WHEN DIW, THE PIVOT POINT IS GENERALLY HALF OF THE DISTANCE FROM THE BOW TO THE STERN. WHEN INITIALLY ORDERING ENGINES FROM DIW, THE PIVOT POINT SHIFTS FORWARD WITH AN AHEAD BELL AND AFT WITH A BACKING BELL.

ONCE FRICTIONAL INERTIA IS OVERCOME AND MOMENTUM FORE OR AFT IS ACHIEVED, THE HYDRODYNAMIC CHARACTERISTICS OF THE HULL WILL TAKE EFFECT. THE PIVOT POINT WILL SETTLE BACK AT ABOUT 1/3 OF THE DISTANCE FROM THE STEM (AHEAD) OR THE STERN (BACKING) WHEN THE SHIP IS STEADY STATE STEAMING.