Which feature on the compass is aligned with the boat's centerline and provides heading information?

Which feature on the compass is aligned with the boat's centerline and provides heading information?

• A. Lubber Line
• B. Bow Line
• C. Keel Line
• D. Stern Line

Answer: (A)

The heading information on a compass is read from a fixed reference line that aligns with the boat’s fore-aft axis—the lubber line. This line is marked on the compass housing and stays aligned with the vessel’s centerline as you hold the compass. When you rotate the compass card to set a heading, you read the degree where the lubber line crosses the compass rose. In other words, the lubber line provides the orientation reference you use to determine which direction the boat is pointing relative to magnetic or true north. Other lines you might hear about aren’t standard reference lines for reading heading on a marine compass, so they don’t serve the same purpose as the lubber line.

The heading information on a compass is read from a fixed reference line that aligns with the boat’s fore-aft axis—the lubber line. This line is marked on the compass housing and stays aligned with the vessel’s centerline as you hold the compass. When you rotate the compass card to set a heading, you read the degree where the lubber line crosses the compass rose. In other words, the lubber line provides the orientation reference you use to determine which direction the boat is pointing relative to magnetic or true north.

Other lines you might hear about aren’t standard reference lines for reading heading on a marine compass, so they don’t serve the same purpose as the lubber line.