Covenant fleet

Covenant naval vessels are commonly organized into fleets. It is unclear exactly how such fleets are organized, or how many fleets there are, but there are likely dozens, if not hundreds of them. Each fleet is essentially a self-sustaining armada. Each fleet is given a unique name with religious connotations similar to how Covenant vessels and colony worlds are named by their beliefs.

Overview
Each fleet is led by a Zealot-class Sangheili, though the title of the fleet commander varies depending on the size and extension of the fleet itself. A large, permanent fleet is commanded by a Supreme Commander, whereas a smaller, temporary task force is led by a lesser Fleet Master. A fleet's highest-ranking individuals convene in a group known as Council of Masters. In some cases, a Minor Prophet is attached to a fleet as a representative of the High Council.

Many known fleets seem to consist of around one hundred starships of all types and variations, and are led by a prominent flagship, which is often a supercarrier or a similarly large and powerful vessel. Capital ships, such as CCS-class battlecruisers and assault carriers, as well as numerous frigates and destroyers that serve as escorts and ensign ships to them. Fleets are sustained agricultural support ships which are attached to them, providing food and supplies to the other ships in the fleet.

A number of combat legions seem to be attached to each Covenant fleet.

Combined fleets
A combined fleet, as its name implies, is comprised of multiple smaller fleets and is led by a Supreme Commander, or, if of sufficient size, an Imperial Admiral. These fleets have larger duties, such as safeguarding and policing entire regions of Covenant-controlled space on their own. These fleets can have several hundred ships. High Charity was guarded by a combined fleet at all times.