Vice Admiral is a flag officer rank of the UNSC Navy, equivalent with the rank of Lieutenant General in the UNSC Marine Corps, UNSC Air Force, and UNSC Army. Vice Admirals generally command the numbered fleets around UNSC controlled space, and are in charge of the naval components of each of the regional unified commands. Of the five numbered fleets, four have command ships which act as the Vice Admiral's flagship.[verification needed]
In informal settings, Vice Admirals are typically referred to simply as "Admiral", but may be also referred to as a "three-star Admiral" to distinguish it from the other ranks of Admiral, so named for the three star rank insignia worn on the uniform.