Emergency Defense Fighter

The Emergency Defense Fighter (EDF) was a late Human-Covenant War initiative by the United Nations Space Command to adapt newly reverse-engineered Covenant technologies for orbital and close-orbit interceptors. The initiative was considered highly secret, with the Sabre component's existence being denied by three administrations.

Competition
Two sets of corporations would create at least two entrants into the competition; Ushuaia Armory and Misriah Armory would create the YSS-1000 Sabre, while SinoViet Heavy Machinery and Chalybs Defense Solutions would create the S-930 Pegasus. The Sabre would be developed in 2547, with a focus on engagement in orbit over Inner Colony worlds and would feature energy shielding.

16 Pegasus prototypes had been created, with nine rated as "combat ready" by 2552. By the end of the war, a few hundred Sabres were built. All nine "combat ready" Pegasus prototypes were destroyed during the Battle for Tribute, while numerous Sabres participated and were lost in the Fall of Reach.

Eventually, the Sabre would win the EDF for service with the UNSC Navy.

Legacy
The Sabre would secretly go into production as the FSS-1000 sometime following the Covenant War but prior to the Created uprising. It would then be deployed to important sites.

Following the war, a "stripped down" version of the Pegasus remained in production and was undergoing evaluation with Tribute's defense forces. This version was tentatively selected to replace the UNSC Air Force's inventory of S-14 Baselards in 2570. The rise of the Created has rendered this impossible for a time.