Wednesday, December 5, 2007


A good docking actually starts long before the ship comes alongside the pier. The approach is at least one third of the docking. If the speed is reduced, the ship properly lined up with the pier or wharf, and then steadied up so that all lateral motion is eliminated, she practically docks herself.

When berthing starboard side to the pier, assuming that the ship has a right hand turning propeller, the ship approaches at only a small angle to the dock. When the engine is put astern to take the headway off the ship the stern moves to port, so if the ship is already at a significant angle to the berth it will be that much more difficult to get the ship flat alongside. It is natural for a ship to behave in this manner at any time when backed, and this behavior is amplified by the quickwater trapped between the hull and berth moving up the ship's side. After the engine is put astern to stop the ship, the stern will move to port and reduce the angle of approach so that the ship comes flat alongside. By using left rudder and a kick ahead with the engine to check that swing to port as the ship comes alongside, the ship can be stopped in position without needing a tug aft.
There will be some modifications to the basic angle of approach for
a starboard or port side to docking, depending on:
1. Wind strength and relative direction.
2. Set and drift of the current.
3. Ship's draft and freeboard.
4. Ship's power and steering characteristics.
5. Whether the pier has an open or solid face.
6. Physical configuration of the berth.
7. Availability of adequate tug assistance.
8. Presence of other vessels in the berth or slip.

These factors all affect the docking of ship.