Anchor windlass

A "windlass" is a machine used on ships that is used to let-out and heave-up equipment such as for example a ship's anchor or a fishing trawl.

An anchor windlass is a machine that restrains and manipulates the anchor chain on a boat, allowing the anchor to be raised and lowered by means of chain cable. A notched wheel engages the links of the chain or the rope. A "trawl windlass" is a similar machine that restrains or manipulates the trawl on a commercial fishing vessel. The trawl is a sort of big fishing net that is wound on the windlass. The fishermen either let-out the trawl or heaves-up the trawl during fishing operations. A brake is provided for control and a windlass is usually powered by an electric or hydraulic motor operating via a gear train.

Horizontal or vertical

Technically speaking, the term "windlass" refers only to horizontal winches. Vertical designs are correctly called capstans. Horizontal windlasses make use of an integral gearbox and motor assembly, all typically located above-deck, with a horizontal shaft through the unit and wheels for chain and/or rope on either side. Vertical capstans use a vertical shaft, with the motor and gearbox situated below the winch unit (usually below decks).