BOTH INTERNATIONAL & INLAND Which vessel...

🔍 Key Concepts

• Rule 23 – Power-driven vessels underway and when two masthead lights in a vertical line are required • Rule 24 – Towing and pushing and how tow length affects masthead light requirements • The difference between vessels restricted in their ability to maneuver, vessels not under command, and sailing vessels in the lights and shapes section

💭 Think About

• For each choice, ask: Is this vessel considered power-driven, towing, restricted in ability to maneuver, not under command, or sailing, according to the Navigation Rules? • Think about which of these vessel types is specifically required by the rules to show two masthead lights in a vertical line under the conditions described. • Which of these vessels would ALWAYS have its status made very clear at night by a distinctive combination of red/green/white lights beyond just masthead lights?

✅ Before You Answer

• Check Rule 23 for power-driven vessels to see when one vs. two masthead lights are required. • Check Rule 24 to see how the length of the tow (in meters) changes the masthead light requirement. • Verify in the lights section what special light combinations are used for vessels not under command and vessels restricted in their ability to maneuver, and whether these combinations necessarily include two masthead lights in a vertical line.

BOTH INTERNATIONAL & INLAND Which vessel MUST show two masthead lights in a vertical line?

A sailing vessel towing a small vessel astern

A power-driven vessel less than 50 meters in length with a 20-meter tow

A vessel engaged in dredging

A vessel not under command

🔍 Key Concepts

💭 Think About

✅ Before You Answer