What line controls the ship from going aft while moored?

The line that controls a ship from going aft while moored is the forward spring line. This type of line is typically rigged diagonally from the ship's bow to a mooring point on the pier or dock. By applying tension to the forward spring line, it effectively prevents the vessel from moving towards the aft, or back, direction. This line works in conjunction with other mooring lines to provide stability and security while the ship is docked.

In comparison, the aft spring line is intended to control movement toward the forward direction, while breast lines are used to hold the ship alongside the dock. The painter line is commonly used for smaller watercraft and does not serve the same function in large vessel mooring. Understanding the role of each type of line helps in effective vessel management while moored.