🔍 Key Concepts

• center of flotation (LCF) and how it relates to trimming moments • difference between trim (fore-and-aft) and list (side-to-side) • what TPI (tons per inch immersion) represents and what actually changes it

💭 Think About

• If a weight is added exactly at the center of flotation, does it create a trimming moment about that point? Why or why not? • When you add or remove weight anywhere on the vessel, what must happen to the vessel’s average (mean) draft to support that new displacement? • Is TPI a property that changes every time you add/remove a little weight, or is it primarily a hydrostatic characteristic at a given draft/shape?

✅ Before You Answer

• Be clear on whether list is caused by off-center weights or by weights on the centerline. • Decide whether trim can change when the moment arm to the LCF is zero. • Recall that TPI is linked to the waterplane area at a given draft, not to a single loading action at a point.