Kusanagi-Class Stealth Frigate

Kusanagi-Class Stealth Frigate Prowlers fill a vitally important niche within the UNSC Navy - they are able to covertly gather a wide range of intelligence types on enemy fleet movements, communications, and locations, and interpret and provide that intelligence to FLEETCOM for analysis. In combat, they can engage in electronic warfare operations, jamming Covenant targeting systems and sensors, guiding UNSC missiles to their targets, and providing an up-to-the-minute picture of the battlefield for the Fleet. The only limitation is their size - previously, stealth features were only truly feasible on ships approximately corvette-size. Technically, it was possible to refit a frigate for stealth, but the disadvantages meant that these were isolated instances - the exorbitant costs of constructing and maintaining such ships meant that they payoff was small. The only stealth frigate that saw any success, the Midsummer Night, was retired soon after entering service because it was simply beyond the Navy's budget to repair and refit her to return to active duty.

The advances made late on the war, and afterward, rendered this size limitation a moot point. The development of the Tarnhelm metamaterial in particular meant that much larger ships could be retrofitted with stealth capabilities, allowing the Office of Naval Intelligence to field a much wider array of stealth craft for different missions. Prowlers would still serve as the primary stealth ship of the Prowler Corps, but the Kusanagi-Class Stealth Frigate was developed to make use of UNSC stealth in situations that Prowlers were less useful - covert troop insertions, battlefield electronic warfare, and orbital support. During the War of Vengeance, and the Battle of Unmoving Virtue in particular, the Kusanagi's would prove one of the most capable warship designs to enter service in the UNSC Navy, proving themselves in a dozen combat theatres.