🔍 Key Concepts

• Use Sheet 2 – Hydrostatic Data at the original mean draft to find TPI (tons per inch immersion) and MT1" (moment to change trim 1 inch). • Work with longitudinal moments about amidships: treat loads forward of amidships as one sign and loads aft as the opposite sign; treat discharges as negative weights. • Separate the problem into change in mean draft (from total weight change) and change in trim (from trimming moment), then apply trim to bow and stern based on their distances from the LCF (Longitudinal Center of Flotation).

💭 Think About

• First, compute the initial mean draft from the given forward and aft drafts. At that mean draft, which TPI and MT1" values from Sheet 2 apply? • When you add up all weights and their moments about amidships, does the net effect tend to trim the ship more by the bow or by the stern? How does that direction of trim affect the forward and aft drafts? • After you find the total change in trim (in inches), how do you split that change between bow and stern using the distances from the LCF to each end of the ship? What happens to the mean draft at the same time due to the net weight change?.

✅ Before You Answer

• Be sure you have the correct sign convention: forward vs aft, load vs discharge, so your net trimming moment direction makes physical sense. • Confirm you are taking TPI and MT1" at the correct mean draft (the original mean draft before loading changes, not at one of the end drafts). • After applying both mean draft change and trim, re-check that the final forward and aft drafts average to the new mean draft and that the direction of trim matches your net trimming moment.