🔍 Key Concepts

• Look carefully at the shape pattern: ball – diamond – ball in a vertical line • Review Navigation Rules Rule 27 – Vessels Not Under Command or Restricted in Their Ability to Maneuver (day shapes) • Recall the specialized operations that are classified as "restricted in ability to maneuver" (e.g., dredging, cable laying, mineclearance, towing, etc.)

💭 Think About

• Which of the answer choices describes a vessel whose work equipment would severely limit her ability to keep out of the way of other vessels? • For each choice, ask yourself: what is the standard day shape for that type of vessel, and does it match ball–diamond–ball or something different (like a single flag or three balls)? • Think about which operations have their own unique day shape (for example, mineclearance has a very distinctive pattern) and which use the general RAM signal instead.

✅ Before You Answer

• Confirm that ball–diamond–ball vertically is the generic signal for a vessel restricted in her ability to maneuver under Rule 27(b)(i) of the Navigation Rules. • Eliminate any answer choices that normally use a single shape or three identical shapes rather than a mixed set of shapes. • Match the remaining answer to an operation that is specifically listed in Rule 27 as an example of a vessel restricted in her ability to maneuver (such as dredging, underwater operations, or cable laying).