Crewman Crewman was an enlisted rank of often limited responsibility or entry level duties , used by service organizations in various culture s , including Starfleet . In Klingonese , this rank was comparable to the rank of " bekk " in the Klingon Defense Force . ( ) Thought not only a rank , the term " crewman " on many occasions was used as a generic term used to refer to any member of a crew , as was the case of Vina , an individual who was listed on the expedition as " an adult crewman " in 2236 . ( ) This was especially true of numerous Starfleet crewmen , who , regardless of rank , officer s and enlisted personnel alike , were referred to as " crewman " . ( ; ; et al . ) In both the 22nd century Earth Starfleet and the later 24th century Federation equivalent , the rank of crewman was further broken down into several classes : crewman , 1st class , crewman , 2nd class and crewman , 3rd class . ( ; ) During the late 23rd century , a Starfleet crewman may have also been rated as an able seaman . ( – ) In addition , the similar rating of able crewman was used during the 22nd century aboard civilian merchant ships , such as those operating under the Earth Cargo Authority . After his less - than - impressive dealings with the Nausicaan s in 2151 , First Officer Matthew Ryan of the freighter was demoted to able crewman in order to have to earn back Captain Keene ' s trust . ( ) In 2151 , Commander threatened Lieutenant Malcolm Reed that he was going to " " bust your ass back to crewman , second class for insubordination , " " though Reed countered , " " Be my guest . I could use a little less responsibility . " " ( ) Two years later , Captain Jonathan Archer gave Reed the same warning , heeding that , " " If I were the kind of captain you think I should be I ' d bust your ass back to crewman , " " following Reed ' s critique of Archer ' s command style . ( ) When Q abducted Captain Jean - Luc Picard in 2365 , and described his desire to join the crew of the , he expressed being " " Ready and willing . Able to serve . . . " " Picard interrupted him , inquiring , " " What would you do ? Would you start as an ordinary crewman ? " " ( ) Appendices . Background information . Gene Roddenberry pushed the assumption that " " every man and woman aboard the is the equivalent of a qualified astronaut , therefore an officer . " " ( " The Making of Star Trek " , p . 209 ) Reiterating , this was most typically in " The Original Series " , where it was evident that a " crewman " was less of a reference to a rank than it was a general term for any member of the crew . One example appears in the episode , where Kirk noted Lieutenant as " Crewman Jackson " in his captain ' s log , and referred to the missing Lt . Sulu and lieutenant commander Scott as " my two missing crewmen " ( vs . " officers " ) . Although " Star Trek " has often been ambivalent about enlisted ranks and insignia , the term " crewman " has been in use since . Visually , any crewmember with the rank below lieutenant , most notably ensign s , wore no visible rank insignia , with the exceptions of CPO Garison and lieutenant junior grade Joe Tormolen . Though in the case of , Benjamin Sisko quickly identified Miles O ' Brien , who wore no insignia on his sleeves , as an " ensign " . Information pertaining to the " able seaman " rank originated from Robert Fletcher ' s personal costuming notes ( p . 9 , seen ) and later confirmed in multiple lots sold in the It ' s A Wrap ! sale and auction . In , it was established in dialogue that Simon Tarses was an enlisted crewman who had not gone to the Academy ; he had a blank collar . This lack of rank insignia for crewmen and noncoms was used throughout " " and " " , although chief petty officers were occasionally assigned different insignia . Several rank insignia were sold off on the It ' s A Wrap ! sale and auction on eBay , including a crewman second class patch . Finally , as ranks established in " Star Trek " were mostly based on the ranking systems of " real world " militaries , the following may also be true : The title of " crewman " was the lowest enlisted rank , subordinate to a petty officer . In comparison to infantry ranking systems , this rank was approximately equivalent to the grade of private .