Boatswain's Mates (BM) train, direct, and supervise personnel in ship's maintenance duties in all activities relating to marlinespike, deck, boat seamanship, painting, upkeep of ship's external structure, rigging, deck equipment, and boats; take charge of working parties; perform seamanship tasks; act as petty officer-in-charge of picketboats, selfpropelled barges, tugs, and other yard and district craft; maintain discipline as master-atarms and police petty officers; serve in, or take charge of, guncrews or damage control parties; and operate and maintain equipment used in loading and unloading cargo, ammunition, fuel, and general stores.

Signalmen (SM) stand watches on signal bridges; send and receive messages by flashing light, semaphore, and flaghoist; prepare headings and addresses for out-going messages; handle, route, and file messages; encode and decode message headings; operate voice radio; maintain visual signal equipment; render passing honors to ships and boats; display ensigns and personal flags during salutes and during personal and national honors; perform duties of lookouts; send and receive visual recognition signals; repair signal flags, pennants, and ensigns; take bearings, recognize visual navigational aids, and serve as navigators' assistants.