Boatswain ' s mate ( United States Navy ) The United States Navy occupational rating of boatswain ' s mate ( abbreviated as BM ) is a designation given by the Bureau of Naval Personnel ( BUPERS ) to enlisted members who are rated or " striking " for the rating as a deck seaman . The colloquial form of address for a boatswain ' s mate is ' Boats ' . The rating of Boatswain ' s Mate dates from the American Revolutionary War and is one of the oldest U . S . Navy rates still in continuous existence . Job description . Boatswain ' s mates train , direct , and supervise personnel in ship ' s maintenance duties in all activities relating to marlinspike , deck , boat seamanship , painting , upkeep of ship ' s external structure , rigging , deck equipment , and boats . Boatswain ' s mates take charge of working parties ; perform seamanship tasks ; act as petty officer - in - charge of picketboats , self - propelled barges , tugs , and other yard and district craft . They serve in , or take charge of damage control parties . BM ' s also operate and maintain equipment used in loading and unloading cargo , ammunition , fuel , and general stores . BMs take charge of and supervise UNREP ( Underway Replenishment ) procedures and equipment . They are integral to ship ' s navigation and serve as ship ' s Helmsman and the ship ' s Lee Helmsman . In addition they also serve as RHIB ( Rigid - hulled inflatable boat ) coxswains . Boatswain ' s mates enjoy a normal path of advancement to Chief Warrant Officer and Limited Duty Officer . Candidates must have normal color perception , and no speech impediment . Candidates need not meet any special citizenship or security requirements . Boatswain ' s mates also stand watch on ship ' s bridges , passing information relating to routine and special activities to the crew with the distinctive boatswain ' s call or boatswain ' s pipe . On the ancient row - galleys , the boatswain used his pipe to " call the stroke . " Later , because its shrill tune could be heard above most of the activity on board , it was used to signal various happenings such as knock - off and the boarding of officials . So essential was this signaling device to the well - being of the ship , that it became a badge of office and honor in the British and American Navies . Boatswain ' s mates duties cover a large spectrum and range widely depending on the capacity and mission of the vessel or shore installation to which BMs are assigned . They act as landing signalmen enlisted ( LSE , guiding helicopters to the designated flight deck of a ship ) on air - capable ships . They act as or supervise lookouts of Navy ships , searching the sea for enemy vessels and hazards to navigation . They conduct Search and Rescue ( SAR ) operations and can respond to other military and civilian ships that request assistance . Ashore , they provide armed security for either their assigned vessel or for their assigned Naval installation . Boatswains ' mates are also a source rating for the Navy ' s mobile amphibious community . These duties include assault boat coxswain and Craftmaster , navigating specialized assault or working vessels during amphibious operations , salvage work , or inshore work . They are also a recognized source rating for the U . S . Navy ' s Special Warfare and Special Operations communities . Should a Boatswain ' s Mate meet eligibility requirements , he can elect to become an SO ( formerly SEAL ) , SB ( formerly SWCC ) , an ND ( Navy Diver ) , or EOD ( Explosive Ordnance Disposal Technician ) . ND and EOD are currently the only special communities open to both men and women . Ship ' s boatswain . In the U . S . Navy the ship ' s boatswain is an officer who assists the first lieutenant by supervising the deck force in the execution of major seamanship functions and the maintenance of topside gear . The ship ' s boatswain supervises cargo handling and inspects and maintains rigging and deck gear . His duties also include supervising anchoring , mooring , fueling , towing , transferring of personnel and cargo , and the operation and maintenance of ship ' s boats . The ship ' s boatswain is in charge of what the Navy deems " unusual " seamanship operations such as retrieving target drones , and also schedules training for deck division personnel . Another key duty of the ships ' boatswain is supervision of the maintenance of abandon - ship equipment and instruction in abandon - ship techniques . Background . The word boatswain has been around in one form or another longer than Modern English has ( Modern English only dates back to the beginning of the Renaissance ) . It is derived from late Old English " batswegen " , from " bat " ( " boat " ) + Old Norse " sveinn " ( " swain " ) , meaning a young man , a follower , retainer or servant . Various phonetic spellings ( such as " " bosun " " and " " Bos ' n " " ) have also been in use through the centuries . Originally , on board sailing ships the boatswain was in charge of a ship ' s anchors , cordage , colors , deck crew and the ship ' s boats . The boatswain would also be in charge of the rigging while the ship was in dock . The boatswain ' s technical tasks have been modernized with the advent of steam engines and subsequent mechanisation . Origins in the Royal Navy . The rank of boatswain was until recently the oldest active rank in Great Britain ' s Royal Navy , and its origins can be traced back to the year 1040 . The Royal Navy ' s last official boatswain , Commander E W Andrew OBE , retired in 1990 . In 1040 when five English ports began furnishing warships to King Edward the Confessor in exchange for certain privileges , they also furnished crews whose officers were the master , boatswain , carpenter and cook . Later these officers were " warranted " by the British Admiralty . They maintained and sailed the ships and were the standing officers of the navy . Soldiers commanded by captains would be on board the ships to do the fighting , but they had nothing to do with sailing the ships . The word " soldiering " came about as a seaman ' s term of contempt for the soldiers and anyone else who avoided shipboard duties . The warranted officers were often the permanent members of the ships ' companies . They stayed with the ships in port between voyages as caretakers , supervising repairs and refitting . Other crewmen and soldiers might change with each voyage . Early in the Fourteenth Century , the Purser joined the warrant officers . He was originally " the clerk of burser . " During the following centuries the gunner , surgeon , chaplain , master - at - arms , schoolmaster and others signed on . In the Royal Navy the task of disciplining the crew fell to the quartermaster s and quartermaster ' s mates . This was done using a rattan boatswain ' s cane on the boys and a rope ' s end on adult sailors . Punishment could lawfully be inflicted on an officer ' s instruction or at his own will , or more formally on deck on the captain ' s or a court martial ' s orders . Birching or use of the cat o ' nine tails would have been typical in the latter case . In a large crew he could delegate this to the boatswain ' s mates , who might alternate after each dozen lashes . Notable boatswains . A number of boatswains mates have achieved notable careers in the military . Carl Brashear , the first black American Master Diver , and whose life was the inspiration for the movie " Men of Honor " , retired as a master chief boatswain ' s mate . Reuben James and William Wiley famous for their heroism in the Barbary Wars and namesakes of the ships USS " Reuben James " ( FFG - 57 ) and USS " Wiley " ( DD - 57 ) were U . S . Navy boatswain ' s mates . Medal of Honor recipients Francis P . Hammerberg , and George Robert Cholister were U . S . Navy boatswain ' s mates , as was Navy Cross recipient Stephen Bass . USS " James E . Williams ( DDG - 95 ) is an Arleigh Burke class destroyer , named for BM1 James E . Williams who was awarded the Medal of Honor while serving in the " brown - water navy " in Vietnam . In 1958 BMCM Sherman Byrd became the first African American Explosive Ordnance Disposal Technician .