Fleetmaster
From Halopedia, the Halo wiki
The Fleet Master is a high-ranking Elite within the Covenant. This grade of Zealot commands Task Forces and small fleets.
Rank
Fleet Master is the highest version of Zealot except for Supreme Commander. Normally, they act as the Ship Master and control only one ship, but when a small part of a fleet is called upon for a special mission or is simply needed elsewhere away from the rest of the fleet, a Fleet Master commands those few ships during that task. This shows they could be the Covenant equivalent to a UNSC Rear Admiral. They may also command the entire fleet if the Supreme Commander or the Imperial Admiral would die during space combat.
They normally operate from a large warship, as a Reverence-class Cruiser, but not as big as a Assault Carrier or Supercarrier. This can especially be seen in Halo:Ghosts of Onyx, as the Imperial Admiral (Xytan 'Jar Wattinree), commanded from a Supercarrier, while the Fleet Master (Voro 'Mantakree), operated from a Reverence-class Cruiser.
Armor
As with all Zealot Elite ranks, the Fleet Master has golden armor.
Role
Only one Fleet Master is officially known, Voro 'Mantakree, who commanded a small task force to Onyx in order to follow the Covenant Destroyer Bloodied Spirit. Template:Elite Ranks
