🔍 Key Concepts

• GM (metacentric height) depends on ship’s displacement and vertical center of gravity (KG) – think about which parts of this problem actually change KG. • Longitudinal cargo movements mainly affect LCG and trim, not transverse stability, so separate trim effects from GM effects in your mind. • In the white pages for SS AMERICAN MARINER, the available GM is usually found from a table as a function of displacement and mean draft. Your cargo changes will alter the final displacement and mean draft.

💭 Think About

• First, compute the net change in displacement from all the loads and discharges. Is the ship finally heavier or lighter, and by how many tons? • Next, using each weight’s distance forward or aft of amidships, find the algebraic sum of longitudinal moments and determine the new LCG. How will that affect the ship’s trim and mean draft when you go to the hydrostatic tables? • When you look up hydrostatic data for the final condition in the white pages, which column(s) give you information that can be turned into an available GM, and do you need to apply any correction (like free surface) for this particular question?

✅ Before You Answer

• Be sure your sign convention is consistent: choose forward moments as positive (or negative) and keep it that way for all four weights. • Verify your final displacement matches one of the displacements (or requires interpolation) in the SS AMERICAN MARINER tables before reading off KM/GM-related values. • Double-check whether the question requires any free surface correction; if not mentioned, the available GM from the table may be used directly without further adjustment.