You are steaming on a course of 058° T at...

Question 1 of 2707066636eea28f7522a1c51b624

You are steaming on a course of 058° T at 11.5 knots. At 0209 you observe a lighthouse bearing 129° T. At 0252 the lighthouse bears 173° T. What is your distance off at the second bearing?

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Question 1 of 27070

You are steaming on a course of 058° T at 11.5 knots. At 0209 you observe a lighthouse bearing 129° T. At 0252 the lighthouse bears 173° T. What is your distance off at the second bearing?

🔍 Key Concepts

• Running fix using two bearings of a single object • Converting time run and speed to distance made good in nautical miles • Using the relationship between course line, bearings of the object, and perpendicular distance (closest point of approach)

💭 Think About

• How far do you travel between 0209 and 0252 at 11.5 knots, and how many minutes is that time interval? • When you plot both bearings of the lighthouse from your course line, where does the lighthouse lie relative to your track, and how does that help you find your perpendicular distance off at the second bearing? • How does the angle between your track and the line from your second position to the lighthouse relate to the distance you have run between the two bearings?

✅ Before You Answer

• Be sure you convert minutes of time to hours correctly before multiplying by speed in knots • Verify you are plotting true bearings from the ship to the lighthouse, not the reverse • Check that your final distance off is a reasonable fraction or multiple of the run between bearings—if it’s larger than the distance you ran, reconsider your geometry