🔍 Key Concepts

• Relative motion of bearings over time when your course and speed are steady • Using a running fix / abeam bearing idea: when an object is exactly abeam, the line of position is perpendicular to your track • Converting time difference and speed into distance run along track

💭 Think About

• How much time passes between the first and second bearings, and what distance along your track do you travel in that time at 13 knots? • If the bearing moves from 243° T to 267° T while you are on 194° T, what does that tell you about the light’s position relative to your track—has it passed ahead, abeam, or aft? • When the object is exactly abeam, what is the geometrical relationship between your track, your position at that instant, and the line from you to the light?

✅ Before You Answer

• Be sure you convert minutes of time to hours before using speed × time to find distance run • Sketch your course line (194° T) and plot the two bearings from your track; check that the bearing change direction makes sense with your sketch • Confirm that your final distance off abeam is a perpendicular distance from the track, not the slant distance from one of the observed positions to the light