The windlass is a horizontal rotating shaft machine used for raising or lowering a vessel's anchor. It may be electrical, hydraulic or steam powered.
Generally located in the forecastle, above the chain locker, a windlass is used to manipulate the anchor chain/cable, allowing it to be raised or lowered. A windlass might be either single, for handling a single anchor, or double, permitting the manipulation of two anchors.When the weight of chain and anchor is considerable, the windlass has a stopper in order to keep the chain/cable from slipping when the wildcat clutch is released.
The windlass has two main parts: the wildcat and the warping-end. The wildcat is a notched wheel that engages the chain links. The warping-end allows for the manipulation of lines.
Chain diameter and weight have to be taken into account when selecting a windlass. The beam in the forecastle is another criterion when selecting a single or double windlass.
