Question 1 of 2921866636eea28f7522a1c51b55c

You sight North Dumpling Island Light in line with Latimer Reef Light (LAT 41°18.2'N, LONG 71°56.0'W) bearing 091° per standard magnetic compass. If your vessel was heading 246° per standard magnetic compass at the time, which of the following is TRUE?

Back
Back
Back
Question 1 of 29218
Study area:
Study area:
Q

You sight North Dumpling Island Light in line with Latimer Reef Light (LAT 41°18.2'N, LONG 71°56.0'W) bearing 091° per standard magnetic compass. If your vessel was heading 246° per standard magnetic compass at the time, which of the following is TRUE?

No Illustration

This question does not have an illustration

🔍 Key Concepts

• Relative bearings vs. compass headings – how to interpret a bearing taken on a fixed line of position when you know the ship’s heading • Compass error = variation + deviation – relationship between true, magnetic, and compass directions • How an observed bearing that should be true (from charted positions) compares to the bearing read on the standard magnetic compass

💭 Think About

• Think about what the true bearing of the line between Latimer Reef Light and North Dumpling Island Light should be from your position. How would you find or estimate that from a chart? • Once you have a true bearing and a compass bearing of the same line, what is the compass error, and how do you decide if that error is east or west? • After finding compass error on that heading, how can you separate variation and deviation, and what does that tell you about the possible relationships listed in the choices?

✅ Before You Answer

• Be clear on the sign convention: is a west error added to or subtracted from true to get compass? Write out the full formula carefully. • Confirm which way you apply variation and which way you apply deviation when converting between true, magnetic, and compass bearings. • Before choosing, check whether the numerical size and sign of the error you found could make deviation equal to, opposite to, or different from the known variation for that area.