Ideal Boat Hull Calculator

Select which parameter to compute
LWL (waterline length, ft.)
BWL (waterline beam, ft.)
Cp (prismatic coefficient)
Displacement (lbs.)
CSA (cross section area)
Use minimum wetted surface? *
Salt water Fresh water
LB (Length-to-Beam ratio) 

©1999 by Joseph Oster - All Rights Reserved.

  1. Units are in feet and pounds.

  2. The parameter to be computed is always derived and cannot be input.  Click the circle in the right column to indicate which parameter to compute from the other values entered.

  3. CSA is the maximum cross sectional area of the hull; on a proa this is at the mid point.

  4. * IMPORTANT!!!  If "Use minimum wetted surface" is checked then CSA may not be entered manually.  A semicircle cross section is assumed where Draft=BWL / 2 and CSA=(pi * Draft^2) / 2.

  5. If "Use minimum wetted surface" is not checked then CSA must be entered manually and BWL is used only to calculate "Length-to-Beam ratio"; the shape of the cross section is up to you!

  6. LB is always derived and cannot be input.

  7. If in doubt about the results, use the "Calculate!" button.

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