Thursday, December 6, 2007


Shallow water affects the ship's maneuverability. As the depth de­creases, the ship's tactical diameter increases and she becomes more directionally stable. The ship may need as much as twice the room for large course changes in shallow water as she would in deep water, so it becomes important to approach a shallow water anchorage at slow speed. Remember also that the ship will twist somewhat more in shallow water while going astern during a maneuver. Deep water also affects anchoring because the anchor has to be put down differently in an unusually deep anchorage. In depths greater than about 100 feet the brake may not be able to stop the chain if the anchor is let go from the hawse, because the chain's weight and the momentum developed as the anchor and chain free-fall that distance exceed the capacity of the brake.

The anchor should be walked out in such deep anchorages by engaging the wildcat and backing the chain out of the locker using the windlass, lowering the anchor nearly to the bottom before disengaging the wildcat, and letting the anchor fall free the last few fathoms to the bottom. During these operations the shiphandler must hold the ship in position for an extended period of time, even in strong winds and currents, a task made easier if the ship can first be brought to her final heading.