Lines (or cables) used to secure a ship at a berth. Mooring lines should be arranged as symmetrically as possible about the midship point of the ship.
- Breast lines – Mooring lines leading ashore as perpendicular as possible to the ship fore and aft line. Breast lines restrain the ship in one direction (off the berth).
Note: Due to collision with shore gantry cranes, breast lines are not used in container terminals.
- Head lines – Mooring lines leading ashore from the fore end or forecastle of a ship, often at an angle of about 45 degrees to the fore and aft line.
- Spring lines – Mooring lines leading in a nearly fore and aft direction, the purpose of which is to prevent longitudinal movement (surge) of the ship while in berth. Spring lines restrain the ship in two directions: headsprings prevent forward motion and backsprings aft motion.
- Stern lines – Mooring lines leading ashore from the after end or poop of a ship, often at an angle of about 45 degrees to the fore and aft line.
Further reading: Loss Prevention Report “Understanding mooring accidents”, it can be freely downloaded from www.ukpandi.com