The Legend-class national security cutter (NSC) is built by Huntington Ingalls Industries (formerly Northrop Grumman Ship Systems) for the US Coast Guard (USCG) under the Deepwater programme.
NSC is the largest and most technically advanced class of cutter in the USCG fleet. The NSCs replace the ageing 378′ High Endurance Hamilton-class cutters in service since the 1960s.
The combat ships can be deployed in homeland security, law enforcement, patrolling, maritime safety, environmental protection, and national defence missions.
Legend-class cutter programme
In June 2002, the USCG signed a $17bn contract with Integrated Coast Guard Systems (ICGS, a joint venture of Northrop Grumman and Lockheed Martin) for the Deepwater Programme. The programme includes delivery of 91 (eight NSC, 25 OPC, and 58 FRC) new cutters, 35 fixed-wing aircraft, 34 helicopters, 76 UAVs, 93 upgraded helicopters, and 49 upgraded cutters over a 20-year schedule.
In July 2005, the programme was expanded to 25 years due to post-9/11 mission requirements. As a result, the contract value increased to $25bn.
National Security Cutter design and features
The NSC-type is the largest combat ship in the USCG fleet. After reviewing the NSC design between 2002 and 2004, the USCG raised questions about the ship structure that could preclude the service life of the cutter. Consequently, engineering changes were implemented and structural components were enhanced in collaboration with the US Navy and naval engineering experts to achieve the desired 30-year service life.
NSC has an overall length of 127.4m (418ft), a beam of 16.4m (54ft), and a draft of 6.8m (22.5ft). The full load displacement is 4,500t. The ship can accommodate a crew of 120.
Designed to deliver better sea keeping capabilities, the NSC is equipped with facilities to launch and recover improved small boats, helicopters, and unmanned aerial vehicles at higher sea states. The cutter has an increased sustained transit speed in comparison to current vessels, along with greater endurance and range.
The on-board C4 intelligence, survival, and reconnaissance (ISR) system provides real-time situational awareness and enhances interoperability between naval units. The cutters feature NBC detection and defence systems to repel chemical, biological, or radiological attacks.
Two cutter boats (a long-range interceptor and / or a short-range prosecutor) can be stored in the aft launch and recovery area.
The main gun fitted forward is an MK110 57mm gun. It can fire at a rate of up to 220 rounds a minute for a range of nine miles. Close-in air defence capability is provided with a 20mm close-in weapon system (CIWS).
Sensors / radars
The Legend-class NSC is equipped with X&S band surface search radar, EADS 3D air search radar, SPQ-9B fire control radar, and Mk46 electro-optical / infrared sensor.
The 50ft x 80ft flight deck can support the operations of a range of manned and unmanned rotary-wing aircraft. It can accommodate an MH-65C or MH-60T and two vertical launch unmanned aerial vehicles or other combinations. It is also provided with a hangar for aircraft storage.
The SLQ-32 electronic warfare system protects the cutters from anti-ship missiles in an open sea environment. The MK 53 NULKA anti-ship missile self-defence system integrates decoys / launchers, a decoy launch processor (DLP), and a processor power supply (PPS). It can deceive new generation radar homing anti-ship missiles by launching autonomous decoys.
The NSC is powered by a combined diesel and gas turbine (CODAG) propulsion system, integrating a GE LM2500 gas turbine and two MTU 20V1163 diesel engines.
Two diesel engines and a gas turbine deliver a total power output of 49,875shp to the ship. The propulsion system provides a top speed of 28k, a range of 12,000nm, and an endurance of 60 days.
Construction of Legend-class NSCs
Construction began in September 2004 and keel for the lead ship in the class, the USCGC Bertholf (WMSL 750), was laid at Ingalls Shipyard in March 2005. The vessel was launched in September 2006 and commissioned in August 2008.
The second NSC, the Waesche (WMSL 751), was laid down in September 2006, launched in July 2008, and commissioned in May 2010.
The USCGC Stratton (WMSL 752) was laid down in July 2009, delivered in September 2011, and commissioned in March 2012.
The USCGC Hamilton (WMSL 753) was laid down in September 2012 and launched in August 2013. The ship was delivered in September 2014 and commissioned in December 2014. The fifth ship in the class, the Joshua James (WMSL 754), was christened in August 2014 and was delivered in June 2015. The ship entered the USCG’s service in August 2015.
Construction of the sixth vessel, the NSC Munro (WMSL 755), began in October 2013 and the keel was laid in November 2014. The ship was christened in November 2015, delivered to the USCG in December 2016, and commissioned in April 2017.
A long-lead material contract was placed in June 2013 for the seventh ship, the NSC Kimball (WMSL 756), and construction started in January 2015. The keel was laid in March 2016 and the ship was christened in March 2017. The vessel was commissioned in August 2019.
The USCG awarded a $76.5m fixed-price contract to Ingalls Shipbuilding to procure long-lead materials for the eighth NSC, the Midgett (WMSL 757), in June 2014. An additional $499.8m construction contract for the vessel was placed by the USCG in March 2015.
The keel for the NSC Midgett (WMSL 757) was laid in January 2017. The ship was launched in November 2017 and christened in December 2017. It was commissioned in August 2019.
In March 2018, the USCG awarded a $94m contract for the purchase of lead material for the ninth NSC. The keel for the ninth NSC Stone (WMSL 758) was laid in September 2018. The ship was delivered to USCG in November 2020.
The USCG awarded a $930m contract to Ingalls Shipbuilding to build tenth and eleventh NSCs in December 2018. The fabrication for the tenth NSC Calhoun (WMSL 759) was commenced in November 2019. The 11th vessel, NSC Friedman, was named in honour of Elizebeth Smith Friedman in August 2020.