🔍 Key Concepts

• KG (height of center of gravity) vs GM (metacentric height) and which one is normally checked against an allowable limit on a stability booklet load form • Effect of free surface when tanks are slack and why we use KG corrected for free surface in heavy weather/survival conditions • The idea of a maximum allowable KG value at a specific draft or condition (such as survival draft) taken from the stability manual or load line booklet

💭 Think About

• Are we normally trying to prove that GM stays unchanged, or are we trying to prove that our actual KG is below some limiting value at the survival draft? • In heavy weather deballasting, will free surfaces be more or less important, and which stability parameter (GM or KG) do they directly affect in your calculations? • When a question gives you two very close numerical values for KG (62.24 ft vs 62.09 ft), what does that suggest about the precision and significance of the maximum allowable limit you’re expected to compare to?

✅ Before You Answer

• Verify which quantity a stability load form typically compares: actual KG (with free surface) vs maximum allowable KG for that draft/condition • Confirm that free surface corrections always act to raise the effective KG (and therefore reduce GM), not keep GM the same • Pay attention to the wording "does not exceed" and which option correctly reflects checking that the corrected KG is within the allowable limit for survival draft