Fleet admiral

Fleet Admiral is the highest commissioned officer rank of the UNSC Navy, although promotion to this rank is restricted to times of war.

As there is no equivalent in the UNSC Marine Corps, Fleet Admirals outrank all Marine Officers (as well as Navy Officers).

Fleet Admirals typically lead battlegroups charged with the defence of key UNSC planets, such as Earth and, formerly, Reach.

Known Fleet Admirals

 * Fleet Admiral Sir Terrence Hood
 * Fleet Admiral Harper