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Rule 11: Application (Vessels in Sight of One Another) (COLREGS)

Last reviewed October 21, 2026

The short answer

Rule 11 says the rules in Section II of the Steering and Sailing Rules, Rules 11 through 18, apply to vessels in sight of one another. That's where sailing vessels, overtaking, head-on, crossing, give-way, stand-on, and the pecking order live. In sight means seen visually, not on radar.

The rule text

Rules in this section apply to vessels in sight of one another.

International Rules, U.S. Coast Guard Navigation Rules and Regulations Handbook (NAVCEN, 2024 corrected edition), Rule 11

What it means on the water

  • Covers Rules 11 to 18.
  • "In sight" means one can be observed visually from the other (Rule 3(k)).
  • When vessels are not in sight in restricted visibility, Rule 19 applies instead.

International vs Inland

Same in substance. Inland names the range: Rules 11 through 18.

Common exam traps

  • Applying Rule 15 to a radar-only contact in fog.

Try 3 questions on Rule 11

  1. Rules 11 to 18 apply when vessels are:

    1. Within radar range
    2. In sight of one another
    3. In fog
    4. At anchor
    Show answer

    B. In sight of one another Rule 11.

  2. A vessel seen only on radar is:

    1. In sight
    2. Not in sight
    3. Stand-on
    4. Give-way
    Show answer

    B. Not in sight Rule 3(k).

  3. Which rule applies to vessels not in sight in restricted visibility?

    1. Rule 15
    2. Rule 17
    3. Rule 19
    4. Rule 11
    Show answer

    C. Rule 19 Rule 19(a).

Frequently asked questions

What does in sight mean?

One vessel can be observed visually from the other (Rule 3(k)).

Same Inland?

Yes.

Which rules are in Section II?

Rules 11 to 18.

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