The Missile-Class Frigate was developed by the UNSC before the start of the Human-Covenant War. As the Human-Covenant War progressed the use of Missile Frigates lessened due to their lack of firepower against shielded Covenant vessels. However Missile-Class Frigates were still produced as they created an execellent form of anti-aircraft defense with occasions when whole squadrons of Seraph fighters were destroyed in one volley.