The Pegasus-class was the final culmination of those efforts. Federal engineers created two catamaran-style hulls and attached them together with a central fuselage containing the reactor, command deck, and Minovski-craft system (more on this later). Each of the outboard hulls contained its own mobile suit hangar, each with its own launch catapult and space for four mobile suits. A central corridor connects the two, and also stores a mobile suit of its own, for a total of nine. Due to its ablative hull plating (painted in red), it can re-enter Earth's atmosphere by itself, and also acheive escape velocity on its own power (again with the Minovski-craft system).

The Pegasus is armed with two large mega particle cannons, mounted behind the large yellow firing domes on either side of the ship's hull. The domes slide open and the cannons extend from within when preparing to fire. Two large missile launchers are also mounted on each side with a third rear-facing pair mounted further back on the hull for the purpose of discouraging close pursuit. Twelve antiaircraft turrets are mounted in concealed firing ports that also slide open when preparing to fire.

The Pegasus' most radically inventive feature is its Minovski-craft system. Essentially the Federation's version of Zeon's Minovski-craft compressor in play on some of their mobile armors, it allows the Pegasus to fly in atmosphere for virtually unlimited amounts of time.

Many Pegasus class ships would be built to slightly different modifications, but the only one to be produced in any sort of limited production capacity would be this model, nicknamed the "Grey Phantom".