Which signaling action is correct when two power-driven vessels are crossing and you intend to pass within 1/2 mile?

• A. Sound a one- or two-blast signal.
• B. Sound three long blasts.
• C. Do not signal.
• D. Speed up to pass quickly.

Answer: (A)

In a crossing situation with two power-driven vessels, you must clearly communicate your intended maneuver to avoid a collision. When you plan to pass within half a mile, you signal that intention with a short whistle blast: one short blast if you plan to pass on the other vessel’s port side, or two short blasts if you plan to pass on its starboard side. This helps the other vessel understand exactly what you intend to do and adjust course accordingly.

Three long blasts, signaling no signal, or speeding up without signaling don’t communicate your intention and can increase the risk of a collision. The one- or two-short-blast signal is the proper, standardized way to indicate your passing plan.