The following is the formula used to calculate The Angle of Vanishing Stability:
Screening Stability Value ( SSV ) = ( Beam 2 ) / ( BR * HD * DV 1/3 )
BR: Ballast Ratio ( Keel Weight / Total Weight )
HD: Hull Draft
DV: The Displacement Volume in cubic meters. DV is entered as pounds of displacement on the webpage and converted to cubic meters by the formula:
Displacement Volume in Cubic Meters = ( Weight in Pounds / 64 )*0.0283168
The Beam and Hull Draft in this formula are in meters. These values are entered in feet on the webpage and are converted to meters before SSV calculation.
Angle of Vanishing Stability approximately equals 110 + ( 400 / (SSV-10) )
Adapted From: K. Adlard Coles' and Peter Bruce's (editors) Adlard Coles' Heavy Weather Sailing (30th edition) Stability of Yachts in large breaking waves. Chapter 2 pp11-23 International marine, Camden, Maine.
The following is the formula used to calculate The Capsize Screening Formula:
Capsize Screening Formula = Beam / (Displacement / 64)1/3
Displacement is in Pounds
Beam is measured in Feet
Adapted From: Rousmaniere, John The Annapolis Book of Seamanship Boat Selection. Chapter 1 p35 Simon & Schuster, New York, New York.
Close Window to Return to Sailing Course