The UNSC Fifth Fleet was one of the principal naval elements of the UNSC Navy. By the Galactic Era, Admiral Douglas A. Davidson would serve as Commander-in-Chief of the Fifth Fleet, and under his tenure, the Fifth Fleet's vessels included the modern Cydonia-class fleet carrier and the Cyclops-class main battle cruiser; the Fifth Fleet would have at least four Cydonia-class fleet carrier as battle group flagships. Admiral Davidson would direct fleet operations from the UNSC Cydonia, a member of Task Force Phoenix, the flag task force of the Fifth Fleet.