🔍 Key Concepts

• Vessel constrained by her draught – definition in International Rules (COLREGS) • Day shapes for different vessel conditions (e.g., not under command, restricted in ability to maneuver, fishing, towing) • Difference between International and Inland requirements for special shapes

💭 Think About

• First recall what it means for a vessel to be "constrained by her draught" and which types of vessels can claim this status • Think through the standard day shapes: balls, cones, diamonds, cylinder – which ones are used for which conditions you already know (e.g., NUC, RAM, fishing, sailing under power) • Ask yourself: is there a unique shape reserved only for a vessel constrained by her draught, and is it one shape or a combination of shapes?

✅ Before You Answer

• Verify in the International Rules (COLREGS) Annex I and Rule 3 that a vessel constrained by her draught has a specific day shape • Confirm which shape is used for vessel restricted in ability to maneuver so you don’t confuse it with constrained by draught • Make sure you are not mixing up shapes used for towing or fishing with the one for constrained by draught