National Security Cutter - Variants

Variants

Huntington Ingalls Industries has proposed two "patrol frigates" for naval use, based on the NSC hull. Patrol Frigate 4501 is very similar to the NSC, the main differences being a modified stern ramp and a knuckleboom crane replacing the overhead crane. The crew is increased to 148, and it was offered to the US Navy as a replacement for the Littoral Combat Ship; the FY13 cost of an LCS was $446.3m compared to $735m for an NSC.

Patrol Frigate 4921 is a more radical redesign with a crew of 141, adding weapons and sensors at the expense of reducing range from 12,000 nautical miles (22,000 km) to 8,000 nautical miles (15,000 km). It adds a 12-cell Mk56 VLS launcher for ESSM air-defense missiles, just behind the main gun which is upgraded from 57mm to a 76 mm Super Rapid. Two quad launchers for Harpoon (missile) anti-ship missiles and a triple launcher for torpedoes are added to the stern. It retains the SeaRAM/Phalanx CIWS and 6 machine guns of other NSC variants. The stern is closed in and houses a towed-array sonar; there is a hull sonar for mine countermeasures and an ESM suite. The original "National Patrol Frigate" concept had an AN/SPY-1F air-defense radar but by 2012 the PF4921 was being shown with an Australian CEAFAR radar. This coincided with HII promoting an NSC variant for the Royal Australian Navy's upcoming Offshore Combatant Vessel project. Brazil, Saudi Arabia and Germany have also shown interest in NSC derivatives.