While on a course of 321°T, a light bears 7°...

Question 1 of 2707066636ee928f7522a1c51948b

While on a course of 321°T, a light bears 7° on the starboard bow at a distance of 9.7 miles. What course should you steer to pass 3.5 miles abeam of the light leaving it to starboard?

Back

Question 1 of 27070

While on a course of 321°T, a light bears 7° on the starboard bow at a distance of 9.7 miles. What course should you steer to pass 3.5 miles abeam of the light leaving it to starboard?

🔍 Key Concepts

• Relative bearing vs. true bearing and how to convert between them • Right triangle off-track distance problems: using sine/cosine with range and desired CPA (closest point of approach) • Determining the course to steer so that the line of relative motion passes at a given abeam distance

💭 Think About

• How can you use the current range to the light (9.7 miles) and the desired abeam distance (3.5 miles) to find the angle between your present line of motion and the line that will give that closest point of approach? • What is the true bearing of the light from your vessel now, and how does changing your course change that bearing at the closest point of approach? • Once you find the required alteration of course (in degrees to starboard or port), how do you apply it to your original course of 321°T to get a new true course?

✅ Before You Answer

• Convert the relative bearing (7° on the starboard bow) into a true bearing from your ship using your present course of 321°T • Use basic trigonometry: relate the current distance (9.7 NM) and desired abeam distance (3.5 NM) to find the angle of turn needed • Check that your new course will leave the light on your starboard side at the closest point, not port, and that it makes sense compared with 321°T