BOTH INTERNATIONAL & INLAND You are in charge of a power-driven vessel making way in dense fog. You observe what appears to be another vessel on radar half a mile distant on your port bow and closing. You must take which action?

Correct Answer: Option A — Sound one prolonged blast

Rule 35(a) requires a power-driven vessel making way through the water to sound one prolonged blast at intervals of not more than two minutes. Radar detection does not alter the requirement to sound the prescribed fog signal for your status as a vessel making way in restricted visibility.