What is the primary purpose of spring lines during docking?

What is the primary purpose of spring lines during docking?

• A. To prevent sideways movement
• B. To keep water out
• C. To adjust line tension
• D. To prevent fore-aft movement

Answer: (D)

Spring lines are used to control fore-aft movement of a vessel at a dock. They run from the bow or stern to a bollard or mooring point on the dock at an angle, so they resist the boat moving forward toward the dock or backward away from it. This helps the boat stay in position as tides rise and fall, wind shifts, or currents change, preventing the vessel from walking along the face of the dock or banging into pilings. Spring lines are especially important for keeping the boat aligned with the pier and maintaining room for other lines to take the load. They differ from lines placed perpendicular to the dock (breast lines), which mainly limit sideways sway. When using spring lines, keep them snug but not overly tight to allow a little movement with the water while still holding the boat in place.

Spring lines are used to control fore-aft movement of a vessel at a dock. They run from the bow or stern to a bollard or mooring point on the dock at an angle, so they resist the boat moving forward toward the dock or backward away from it. This helps the boat stay in position as tides rise and fall, wind shifts, or currents change, preventing the vessel from walking along the face of the dock or banging into pilings. Spring lines are especially important for keeping the boat aligned with the pier and maintaining room for other lines to take the load. They differ from lines placed perpendicular to the dock (breast lines), which mainly limit sideways sway. When using spring lines, keep them snug but not overly tight to allow a little movement with the water while still holding the boat in place.