🔍 Key Concepts

• Rule 23 - Power-driven vessels underway and the special provisions in that rule • How air-cushion vessels (hovercraft) are marked when operating in the non-displacement mode • The difference between lights for vessels restricted in their ability to maneuver and special-purpose lights

💭 Think About

• Look at which of these vessel types has a special yellow light described in the Navigation Rules, separate from normal masthead, side, and stern lights. • Ask which of these options would need an extra warning light because of unusual speed, spray, or operating mode rather than because it is obstructed or restricted. • Consider whether a flashing yellow all-round light is used to show a restriction, a tow, or a special mode of operation.

✅ Before You Answer

• Verify in Rule 23 that one type of vessel is allowed an additional all-round flashing yellow light. • Check whether vessels not under command and vessels restricted in ability to maneuver use red/green/white combinations rather than yellow flashing lights. • Confirm that towing lights and cable-laying lights have their own patterns and colors, and whether any of them involve a single all-round flashing yellow light.