Safe Loading — Subpart C

Calculation of the Maximum Displacement

Example of Maximum Displacement Calculation

Below is an example of the calculations for displacement below the static-float plane for any boat category, following the formulae of the worksheet on Figure 4. In an actual case, all dimensions would be the ones measured off the mold and entered in the form given in Figure 4.

NOTES:

1. Volume in cubic inches of the integral structures aft of the transom and below the static float-plane may be added to the cubic capacity. To determine this, figure the volume of any bustles, integral swim platforms or other structures below the float-plane and add to formula where it says +/- Note 1. On the other hand, any volume of an engine well below the float-plane must be calculated and subtracted from the cubic capacity in the same place. That number in cubic inches divided by 1728 gives the volume in cubic feet.
2. The factor 174600 includes a 5% margin for measurement error.
3. Boat weight includes engine, stern drive, fuel system, fuel and battery weight.
4. The figures used in these examples are taken from the boat dimension drawings in Figure 3. The letters (a, b, c, d, e, and f) have been placed under the dimensions taken from Figure 3 as a further help for the user of this Guideline. All dimensions should be converted to decimal numbers before insertion in the formula.

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