Thursday, December 6, 2007

SHIP HANDLING (QUICKWATER WHEN UNDOCKING)

QUICKWATER WHEN UNDOCKING
The ship's quickwater can be an used during the undocking, such as when backing from a pier, since the ship is passing through the quickwater as she moves astern. (Quickwater is when the flow from the engine going astern starts moving up the side of the ship).
Leaving a starboard side berth the quickwater forces the stern away from the dock or wharf, then moves the ship laterally and, when there is a good flow striking the hull forward of the pivot point, checks up the swing of the bow toward the pier. The more restricted the flow of quickwater along the inboard side of the ship, whether due to shoaling under the berth or to the pier or wharf having a solid face, the more effect it has on the ship.

Quickwater has less effect when leaving from a port side berth since it is less strong on the port side of the ship and is acting in more open water due to the ship's angle to the pier as she starts to back. Quickwater has a effect but does reduce that angle to the berth as it strikes the forepart of the hull.
With some planning, the quickwater can be used to move a ship with the minimum of bells and rudder orders. A ship can be started astern until the stern begins to lift off the pier. The engine is then stopped and the ship drifts astern while the quickwater moves forward to strike the hull ahead of the pivot point. The swing of the bow toward the pier is checked and the ship backs straight astern, clearing the berth in a neat and seamanlike manner.