At 0910, your DR position is LAT 41°11.9'N, LONG 72°47.8'W. Your vessel is on course 097°T at 9.5 knots, and the weather is foggy. At 0915, Branford Reef Light is sighted through a break in the fog bearing 318°T. At 0945, Falkner Island Light is sighted bearing 042°T. What is your 0945 running fix position?
• Running fix using two bearings at different times • Transferring the earlier line of position (LOP) along your dead-reckoning track by distance made good • Using speed = distance / time to find how far you traveled between 0915 and 0945
• From your DR course and speed, how many nautical miles did you travel between the first bearing at 0915 and the second bearing at 0945? • Where would the 0915 bearing line to Branford Reef Light lie if you "moved" it forward along your 097°T track by that distance? • Once you transfer that first LOP, where does it intersect the 0945 bearing to Falkner Island Light, and how does that compare with the DR position at 0945?
• Convert the 30 minutes between 0915 and 0945 into hours correctly before using Speed = Distance / Time. • Make sure your transferred LOP for the first bearing is moved exactly parallel to itself along your DR track, not rotated. • After plotting, check which answer choice is closest to the intersection point and also reasonable compared to your 0945 DR position (it should not be far off your DR track).
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