What is the primary use of a heaving line?

• A. To measure ship speed.
• B. To transfer a line to shore or another vessel or to help mooring.
• C. To cut rope during mooring.
• D. To signal engine RPM.

Answer: (B)

The main idea behind a heaving line is to get a line to shore or to another vessel so you can bring over a mooring line and secure the ship. It’s a light line with a weighted end that’s thrown or heaved across the gap. Once someone on shore or on the other vessel grabs the messenger line, it can be used to haul a heavier line back to the ship, making mooring possible even when you can’t reach with a longer rope. This is especially handy when distance or alignment makes direct line-handling impractical.

Other options don’t fit because a heaving line isn’t used to measure speed, cut rope, or signal engine RPM; those tasks rely on different tools or signals.