Chief Petty Officer
A Chief Petty Officer is a military rank the equivalent of which is used by the service organizations of many civilizations.
Use in Starfleet
Chief Petty Officer is a senior non-commissioned rank currently used by Starfleet. The Marine rank equivalent to Chief Petty Officer is Gunnery Sergeant.
Chief Petty Officers serve in leadership roles in their respective departments, and may also serve in any junior officer post. They generally have many years of service and a wealth of experience in their selected field. A promotion to Senior Chief Petty Officer after five years is common, but not required. Unlike Petty Officer First Class and lower ranks, advancement to Chief Petty Officer not only carries requirements of time in service, superior evaluation scores, and specialty examinations, but also carries an added requirement of peer review. Chief Petty Officers serve a dual role as both technical experts and as leaders, with the emphasis being more on leadership as they progress through the CPO ranks. A recognized, collateral duty for all Chiefs is the training of Junior Officers.
At this rank the crewman can apply for a warrant, demonstrating their technical expertise and leadership skills, to be promoted to Warrant Officer.