At 0907 you change course to 224°T, and your...

Question 1 of 2707066636ee928f7522a1c51908a

At 0907 you change course to 224°T, and your speed is now 13.0 knots. At 0939 Chesapeake Light is bearing 168°T at a distance of 7.1 miles, and Cape Henry Light is bearing 246°T. What were the set and drift since 0907?

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Question 1 of 27070

🔍 Key Concepts

• Set and drift as the difference between DR (dead reckoning) position and observed (fix) position • How to convert time difference to distance run at a given speed using: Distance = Speed × Time (in hours) • Using two LOPs (lines of position) from lights to plot an accurate fix on the chart

💭 Think About

• From 0907 to 0939, how many minutes have passed, and what distance should you have run along course 224°T at 13.0 knots if there were no current? • Once you plot your DR position at 0939 and your actual fix from the two bearings, what is the direction (set) from the DR position to the fix? • How far is it from the DR position to the fix, and, over the elapsed time, what speed of current (drift) does that represent?

✅ Before You Answer

• Be sure to convert 32 minutes into hours correctly before using the speed–distance formula • Confirm that set is always expressed as a true bearing from DR position to fix, not the other way around • Calculate the current’s speed (drift) using: Drift (knots) = Distance between DR and fix (nm) ÷ Time (hours)