You are underway on course 163°T at a speed of 15.8 knots. You sight a buoy bearing 161°T at a radar range of 5.5 miles at 1319. If you change course at 1325, what is the course to steer to leave the buoy abeam to starboard at 1.0 mile?

Correct Answer: Option D — 145°T

At 15.8 knots, the vessel travels 1.58 miles in 6 minutes. Using the initial radar range and bearing, calculate the new course to achieve a 1.0-mile CPA to starboard. Plotting the relative motion vector confirms that 145°T is the correct course to maintain the desired clearance.