You sight North Dumpling Island Light in line with Latimer Reef Light (LAT 41°18.2'N, LONG 71°56.0'W) bearing 089° per standard magnetic compass. If your vessel was heading 297° per standard magnetic compass at the time, which of the following is TRUE?
• Compass error = difference between true bearing and compass bearing • Relationship among true, magnetic, and compass (T–M–C) using variation and deviation • A range (two charted objects in line) gives you a true bearing from the chart
• Use the charted positions of North Dumpling Island Light and Latimer Reef Light to find the true bearing of the range line • Compare your true course (from the chart) with the standard magnetic compass heading and use the T–M–C relationships to determine compass error on that heading • Decide what that single checked heading tells you (and does NOT tell you) about the deviation table and about other bearings
• Confirm the local variation for the area from the chart before doing any conversion • Carefully keep track of west vs east when moving between true, magnetic, and compass (remember standard T–M–C memory aids) • Ask yourself: does a check on one heading prove anything about all bearings, or only about that specific heading?
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