Highly-classified—to the extent that three prior administrations adamantly denied its existence—the Sabre program offers the UNSC’s best option for swift, versatile, and lethal planetary defense. Developed for fighter combat against enemy forces in orbit above Inner Colony worlds, the YSS-1000 or "Sabre" is extensively equipped with a heavy arsenal, a cabin for two operators, and the ability to be launched from a planet’s surface without the use of asynchronous linear-induction, traditional nuclear technology, or other conventional means of off-world transit.
The Sabre is built for the dual purposes of peak acceleration and maneuverability in orbital combat, accomplishing some feats that many ground-to-space-capable vessels are simply incapable of. Its armament further enhances its combat appeal, carting twin M1024 ASW/AC 30mm MLAs and a pair of ST/Medusa missile pods. As such, this craft is intended specifically for lethal encounters, not simply to disrupt, disable or maim targeted craft.
Across the Inner Colonies, there are several well-hidden launch sites, the newest lying on the banks of Farkas Lake on Reach. Apart from their top-secret locations and heavy array of gun batteries, these sites are largely standard launch complexes, consisting of multiple bays, each with various maintenance tiers and control decks. Despite its internally-lauded performance against a Covenant Corvette and, by extension, the supercarrier Long Night of Solace just prior to Reach’s demise, the Sabre project remains a well-guarded secret.