46 CFR §28.575

1. (a)Each vessel must meet paragraphs (f) and (g) of this section when subjected to the gust wind heeling arm and the angle of roll to windward as specified in this section.
2. (b)The gust wind heeling arm, Lw in figure 28.575 of this chapter, must be calculated by the following formula:
3. (c)The angle of roll to windward, A1, is measured from the equilibrium angle, Ael, and is calculated by the following formula:
4. (d)The angle of equilibrium, Ael in figure 28.575, is calculated by determining the lowest angle at which the gust wind heeling arm, Lw, is equal to the righting arm.
5. (e)The area “b” in figure 28.575 must be measured to the least of the following:
   1. (1)The angle of downflooding, (Af);
   2. (2)The angle of the second intercept, ANaN in figure 28.575, of the wind heeling arm curve, Lw in figure 28.575, and the righting arm curve; or
   3. (3)A heel angle of 50° (0.87 radians).
6. (f)The angle of equilibrium, Ael in figure 28.575, must not exceed 14° (0.24 radians).
7. (g)Area “b” in figure 28.575 must not be less than area “a” in figure 28.575.