Legend Class National Security Cutter, United States of America


Legend Class National Security Cutter

Eight Legend Class National Security Cutters (NSCs) are being built under the Deepwater Programme of the US Coast Guard (USCG). Built by Northrop Grumman Ship Systems, NSC is the largest and most technically advanced class of cutter in the USCG fleet. The NSCs will replace the aging 378' High Endurance Hamilton class cutters in service since the 1960s.

NSCs can be deployed in homeland security, law enforcement, 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.

Construction

Construction began in September 2004 and keel for the lead ship in class, USCGC Bertholf (WMSL 750), was laid at Ingalls Shipyard in March 2005. The ship was launched in September 2006 and commissioned in August 2008.

"The NSC-type is the largest combat ship in the USCG fleet."

The second NSC, Waesche (WMSL 751), was laid down in September 2006, launched in July 2008 and commissioned in May 2010.

USCGC Stratton (WMSL-752) was laid down in July 2009, delivered in September 2011 and commissioned in March 2012.

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 class, Joshua James (WMSL 754), was christened in August 2014 and will be delivered in June 2015.

Construction of the sixth vessel, NSC Munro (WMSL 755), began in October 2013 and keel was laid in November 2014. A long-lead material contract was placed in June 2013 for the seventh ship, NSC Kimball (WMSL 756), and construction started in January 2015. The sixth and seventh ships will be delivered in 2016 and 2017 respectively.

The USCG awarded a $76.5m fixed-price contract to Ingalls Shipbuilding to procure long-lead materials for the eighth NSC, Midgett (WMSL 757) in June 2014. An additional $499.8m construction contract for the vessel was placed by the USCG in March 2015. The eighth NSC is scheduled to be delivered in 2019.

National Security Cutter design

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, a beam of 16.4m and a draft of 6.8m. The full load displacement is 4,400t. The ship can accommodate a crew of 110.

Features

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 than current vessels, along with a greater endurance and range.

"In June 2002, the USCG signed a $17bn contract with Integrated Coast Guard Systems."

The onboard 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.

Armament

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 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.

Aircraft

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.

Countermeasures

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 processor power supply (PPS). It can deceive new generation radar homing anti-ship missiles by launching autonomous decoys.

Propulsion

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 28kt, a range of 12,000nm and an endurance of 60 days.