(covers information from several alternate timelines)
Fleet admiral was a military rank, the equivalent of which was used by the service organizations of many civilizations. As a traditional grade, fleet admiral was the most senior flag officer rank of a naval organization, above all the flag admiral grades save for commander-in-chief.
In Starfleet, fleet admiral existed as a separate rank, but was also used as a title awarded and referring to officers wearing insignia of vice admiral or admiral, such as Fleet Admiral Shanthi. (TNG: "Redemption II")
The following admirals wore the insignia for the fleet admiral rank:
- Bill, Commander in Chief
- Bob, Chief of Staff
- Kirsten Clancy, Commander in Chief
- Alexander Marcus (alternate reality)
- Morrow, Commander, Starfleet
- Charles Vance, Commander in Chief
The following admirals were referred to as fleet admirals but wore the rank insignia for vice admiral:
|Enlisted personnel||Commissioned officers||Flag officers|
|ENS||LT JG||LT||LT CMDR||CMDR||CAPT||FCAPT||CDORE||RADM||VADM||ADM||FADM|
|2nd LT||1st LT||CAPT||MAJ||LT COL||COL||BRIG||MAJ GEN||LT GEN||GEN||MARSHAL|
|Services:||Andorian • Bajoran • Cardassian • Ferengi • Human (CSA • Third Reich • UE MACO • USA) • Jem'Hadar • Klingon • Romulan • United Earth/Federation Starfleet • Vulcan|
Mirror universe: Terran Empire Starfleet • Terran Empire MACO
The Star Trek Encyclopedia (3rd ed., p. 210-211) labeled this rank as "fleet admiral" referring to the late 2270's-2350's uniforms, and "fleet admiral, five star" referring to its use on 2350s-2370s, late 2360s-early 2370s, and 2370s uniforms.
Star Trek: The Magazine Volume 2, Issue 10, p. 99, mistakenly identified the late 2270's-2350's admiral insignia as the fleet admiral insignia.