Legend-class cutter: Difference between revisions

| Total ships building = 21<ref name= "NSC10">{{cite web|url=https://news.usni.org/2018/03/30/hii-awarded-94m-long-lead-contract-10th-national-security-cutter#more-32534|title=hii-awarded-94m-long-lead-contract-10th-national-security-cutter|publisher=usni.org|date=30 March 2018|access-date=31 March 2018|archive-url=https://web.archive.org/web/20180331002937/https://news.usni.org/2018/03/30/hii-awarded-94m-long-lead-contract-10th-national-security-cutter#more-32534|archive-date=31 March 2018|url-status=live}}</ref><ref name= "Sep2022_rpt_procure">{{cite web|url=https://news.usni.org/2022/09/02/report-to-congress-on-coast-guard-cutter-procurement-17|title=Report to Congress on Coast Guard Cutter Procurement|publisher=usni.org|date=2 September 2022|access-date=20 October 2022|archive-url=https://web.archive.org/web/20220906184916/https://news.usni.org/2022/09/02/report-to-congress-on-coast-guard-cutter-procurement-17|archive-date=6 September 2022|url-status=live}}</ref>

| Total ships completed = 910<ref name="calhoun_christening">{{cite web |url=https://chuckhillscgblog.net/2022/06/05/uscgc-calhoun-nsc10-christened-4-june-2022/|title=USCGC Calhoun, NSC#10, Christened 4 June, 2022 |date=June 5, 2022 }}</ref><ref name= "Sep2022_rpt_procure"/>

| Total ships active = 910<ref name= NSC10/>

| Ship type = [[United States Coast Guard Cutter]] / Large patrol vessel

| Ship displacement = {{convert|45004600|LT}}

*2 × {{convert|7,400|kW|abbr=on}} [[MTU Friedrichshafen|MTU]] 20V 1163 diesels

*1 × {{convert|22|MW|abbr=on}} [[General Electric LM2500|GE LM2500]] gas turbine engine<ref>{{cite web|url=http://dieselman.wordpress.com/2008/01/30/mtu-powers-deepwater-national-security-cutter|title=MTU Powers Deepwater National Security Cutter|work=The world of Dieselman - MTU|date=January 30, 2008|access-date=2012-03-30|archive-url=https://web.archive.org/web/20120310190837/http://dieselman.wordpress.com/2008/01/30/mtu-powers-deepwater-national-security-cutter/|archive-date=2012-03-10|url-status=live}}</ref>

The '''Legend-class cutter''', also known as the '''National Security Cutter''' ('''NSC''') and '''Maritime Security Cutter, Large''', is the largest active patrol [[cutter (boat)|cutter]] class of the [[United States Coast Guard]], with the size of a [[frigate]]. Entering into service in 2008, the Legend class is the largest of several new [[United States Coast Guard Cutter|several new cutter]] designs developed as part of the [[Integrated Deepwater System Program]].<ref name=DeepwaterNSC>{{cite web |url=http://www.uscg.mil/deepwater/system/nsc.htm |title=National Security Cutter (NSC) |publisher=[[Integrated Deepwater System Program]] |access-date=2007-09-01 |archive-url=https://web.archive.org/web/20070824030749/http://www.uscg.mil/deepwater/system/nsc.htm |archive-date=2007-08-24 |url-status=live }}</ref>

These vessels can be used for a variety of tasks, including environmental protection, search and rescue, fisheries protection, ports, waterways, and coastal security, counterterrorism activities, law enforcement, drug interdiction, defense operations, and other military/naval operations, including assigned naval warfare tasks with the [[United States Navy|U.S. Navy]].<ref>{{cite web|title=National Security Cutter|url=http://ingalls.huntingtoningalls.com/our-products/nsc/|website=ingalls.huntingtoningalls.com|access-date=22 February 2018|archive-url=https://web.archive.org/web/20180306214749/http://ingalls.huntingtoningalls.com/our-products/nsc/|archive-date=6 March 2018|url-status=live}}</ref><ref>{{cite web|title=National Security Cutter|url=http://www.dcms.uscg.mil/Our-Organization/Assistant-Commandant-for-Acquisitions-CG-9/Programs/Surface-Programs/National-Security-Cutter/|website=www.dcms.uscg.mil|publisher=United States Coast Guard|access-date=22 February 2018|archive-url=https://web.archive.org/web/20180325185219/http://www.dcms.uscg.mil/Our-Organization/Assistant-Commandant-for-Acquisitions-CG-9/Programs/Surface-Programs/National-Security-Cutter/|archive-date=25 March 2018|url-status=live}}</ref><ref>{{cite web|title=UNCLASSIFIED LI 4206 - Coast Guard Weapons UNCLASSIFIED Navy Page 1 of 4 P-1 Line #30 Exhibit P-40, Budget Line Item Justification: PB 2015 Navy|url=https://www.dacis.com/budget/budget_pdf/FY15/PROC/N/4206_30.pdf|website=www.dacis.com|access-date=27 July 2017|quote=is prepared to accomplish the assigned naval warfare tasks in concert with USN units|archive-url=https://web.archive.org/web/20170810211509/https://www.dacis.com/budget/budget_pdf/FY15/PROC/N/4206_30.pdf|archive-date=10 August 2017|url-status=live}}</ref>

The Legend-class cutters are the second-longest of all U.S. Coast Guard cutters, behind the research icebreaker {{USCGC|Healy|WAGB-20|2}}, and will replacereplaced the 12 [[Hamilton-class cutter|''Hamilton''-class]] cutters in service.<ref>{{cite web|url=http://defensetech.org/2011/05/23/end-of-an-era-uscg-retiring-hamilton-class-cutters/|title=End Of An Era, USCG Retiring Hamilton Class Cutters -|date=May 23, 2011|access-date=2011-08-21|archive-url=https://web.archive.org/web/20110806221529/http://defensetech.org/2011/05/23/end-of-an-era-uscg-retiring-hamilton-class-cutters/|archive-date=2011-08-06|url-status=live}}</ref> These cutters are envisioned by the Coast Guard as being able to undertake the entire range of the [[high endurance cutter|high-endurance cutter]] roles, with additional upgrades to make it more of an asset to the [[United States Department of Defense|Department of Defense]] during declared national emergency contingencies.<ref name="globalsecurity.org">{{cite web|url=http://www.globalsecurity.org/military/systems/ship/nsc.htm|title=Maritime Security Cutter, Large (WMSL) / National Security Cutter (NSC)|author=John Pike|access-date=2011-08-21|archive-url=https://web.archive.org/web/20110901003351/http://www.globalsecurity.org/military/systems/ship/nsc.htm|archive-date=2011-09-01|url-status=live}}</ref> To facilitate intercept missions, the Legend class can carry and launch both the [[Short Range Prosecutor]] and the [[Long Range Interceptor]] [[rigid-hulled inflatable boat]]s (RHIBs). The cutters are configured to be able to survive in low-threat environments, factorssuch of which includeas an enemy having a poorly equipped military, some coastal patrol craft, and few to no anti-ship cruise missiles. Operations in this environment can also be general defense operations, including theater security, port protection, ship escort, [[Anti-piracy measures|anti-piracy]], and maritime interception operations. The cutters can also survive in medium-threat environments, which can include a fairly well equipped military of ships and aircraft with weapons and radar coverage well offshore, higher numbers of anti-ship cruise missiles, and a possible submarine threat. Operations in this threat environment could include defense operations, naval surface fire support, and the evacuation of noncombatants. The cutters are not expected to survive in a high-threat environment with their current configuration.<ref>{{cite web|title=Deepwater Project Bofors Defense 57-mm L|url=http://www.ppt-sharing.com/ppt-presentation/deepwater-project-bofors-defense-57-mm-l|website=ppt-sharing.com|access-date=2 October 2017|archive-url=https://web.archive.org/web/20171003030434/http://www.ppt-sharing.com/ppt-presentation/deepwater-project-bofors-defense-57-mm-l|archive-date=3 October 2017|url-status=live}}</ref>

Legend-class cutters have increased data exchange bandwidth.<ref name=GS-NSC>{{cite web|title=National Security Cutter (NSC/WMSL)|url=http://www.globalsecurity.org/security/library/report/2005/assetdescriptions.pdf|website=globalsecurity.org|access-date=10 August 2017|quote=The Maritime Security Capabilities allow cutter's weapons and command and control suite to be upgraded and hardened to better survive potential terrorist incidents and process increased data flow|archive-url=https://web.archive.org/web/20080316071519/http://www.globalsecurity.org/security/library/report/2005/assetdescriptions.pdf|archive-date=16 March 2008|url-status=live}}</ref> The [[Hensoldt]], (formerly [[EADS North America]]), TRS-3D radar system provides three-dimensional air and surface search functions, and is used in the LCS program and as the German [[Braunschweig-class corvette|Korvette 130]] program.<ref>{{Cite web |url=http://frontierindia.net/trs-3d-naval-radar-for-us-coast-guard%E2%80%99s-deepwater-programme |title=TRS-3D naval radar for U.S. Coast Guard's "Deepwater" programme - Frontier India - News, Analysis, Opinion |access-date=2011-08-21 |archive-url=https://web.archive.org/web/20120401230223/http://frontierindia.net/trs-3d-naval-radar-for-us-coast-guard%E2%80%99s-deepwater-programme |archive-date=2012-04-01 |url-status=dead }}</ref> The cutters are also equipped with the [[AN/SLQ-32|AN/SLQ-32(V)2]] electronic warfare system, used in the [[DDG-51 class]].<ref>{{cite web|url=https://fas.org/man/dod-101/sys/ship/weaps/an-slq-32.htm|title=AN/SLQ-32 Electronic Warfare (EW) system|access-date=2015-04-04|archive-url=https://web.archive.org/web/20150409032656/https://fas.org/man/dod-101/sys/ship/weaps/an-slq-32.htm|archive-date=2015-04-09|url-status=live}}</ref> The cutters AN/SLQ-32B(V)2 system is to be upgraded under the Surface Electronic Warfare Improvement Program (SEWIP).<ref>{{cite web |title=UNCLASSIFIED LI 2312 - AN/SLQ-32 UNCLASSIFIED Navy P-1 Line #44 Exhibit P-40, Budget Line Item Justification: PB 2020 Navy |url=https://www.dacis.com/budget/budget_pdf/FY20/PROC/N/2312_44.pdf |website=www.dacis.com |access-date=2 September 2019}}</ref>

The Legend class is equipped with the same 220 rpm [[Bofors 57 mm L/70 naval artillery gun|Bofors 57&nbsp;mm gun]] as mounted on the USNU.S. Navy's [[littoral combat ship]]s and [[Constellation-class frigate]]s.<ref>{{cite web|url=http://www.baesystems.com/ProductsServicesen/l_and_a_sea_mk110.htmlproduct/57mm-naval-gun-system|title=Error57MM PageNaval Gun System|access-datepublisher=2011-08-21}}</ref><ref>{{cite web|archive-url=https://web.archive.org/web/20090930201901/http://www.baesystems.com/ProductsServicesen/l_and_a_sea_mk110.html|archivearticle/57mm-date=2009mk-09110-30selected-for-u-s-navys-new-constellation-class-frigates|urltitle=57mm Mk 110 selected for U.S. Navy's new Constellation-statusclass frigates|publisher=dead}}</ref> Guided 57&nbsp;mm ammunition is being developed for the Mk 110 for the Navy and Coast Guard, including for use on the National Security cutters.<ref>{{cite web|title=L3 Mustang Technology Passes U.S. Navy's Critical Design Review for Guided Projectile Program|url=http://www2.l3t.com/mustangtechnology/pdf/pr_Mustang_ALaMO_FINAL(Aug22_2017).pdf|website=www2.l3t.com|access-date=9 January 2018|archive-url=https://web.archive.org/web/20170828012922/http://www2.l3t.com/mustangtechnology/pdf/pr_Mustang_ALaMO_FINAL(Aug22_2017).pdf|archive-date=28 August 2017|url-status=dead}}</ref> The missile defense duties are handled by the Mk 53 Nulka decoy systems, the Mk 36 SRBOC countermeasure systems also used on the FFG-7 and CG-47 programs, and the Phalanx [[CIWS]].<ref>{{Cite web |url=http://www.gregfarnham.com/Family/SWMagazine_files/SW_1sthalf_fall_08.pdf |title=Archived copy |access-date=2011-08-21 |archive-url=https://web.archive.org/web/20120331000141/http://www.gregfarnham.com/Family/SWMagazine_files/SW_1sthalf_fall_08.pdf |archive-date=2012-03-31 |url-status=live }}</ref> The combination of the Mk 110 and the Phalanx gives the cutters [[Anti-surface warfare|anti-surface]] capability, limited air-defense capability, and the capability to provide naval gunfire support.<ref>{{cite web|title=On patrol with Waesche: Firepower|url=http://coastguard.dodlive.mil/2012/04/on-patrol-with-waesche-firepower/|website=USCG.mil|publisher=US Coast Guard|access-date=14 February 2017|archive-url=https://web.archive.org/web/20170215021344/http://coastguard.dodlive.mil/2012/04/on-patrol-with-waesche-firepower/|archive-date=15 February 2017|url-status=live}}</ref>

The cutters have space, weight, and power reserved for additional weapons and systems, which includes mine-warfare systems, non-line-of-sight missiles, and can have a [[SeaRAM]] replace the 20&nbsp;mm Phalanx CIWS.<ref>{{cite web|title=NATIONAL SECURITY CUTTER Enhanced Oversight Needed to Ensure Problems Discovered during Testing and Operations Are Addressed|url=http://www.gao.gov/assets/680/674610.pdf|website=gao.gov|access-date=28 November 2016|archive-url=https://web.archive.org/web/20170127110217/http://gao.gov/assets/680/674610.pdf|archive-date=27 January 2017|url-status=live}}</ref><ref name=Ronald O'Rourke2008>{{cite web|title=Navy Littoral Combat Ship (LCS) Program: Background, Oversight Issues, and Options for Congress|url=https://digital.library.unt.edu/ark:/67531/metadc819055/m2/1/high_res_d/RL33741_2008Nov17.pdf|website=digital.library.unt.edu|access-date=25 August 2017|archive-url=https://web.archive.org/web/20170826032220/https://digital.library.unt.edu/ark:/67531/metadc819055/m2/1/high_res_d/RL33741_2008Nov17.pdf|archive-date=26 August 2017|url-status=live}}</ref> The NSC is capable of carrying a sonar ,that is reported as having mine and underwater swimmer location ability.<ref>{{cite web|title=Revised Deepwater Asset Descriptions|url=https://www.globalsecurity.org/security/library/report/2005/assetdescriptions.pdf|website=Globalsecurity.org|access-date=16 November 2017|archive-url=https://web.archive.org/web/20080316071519/http://www.globalsecurity.org/security/library/report/2005/assetdescriptions.pdf|archive-date=16 March 2008|url-status=live}}</ref> The NSC has an NBC detection and defense system to repel chemical, biological, or radiological attacks and has wash-down systems.<ref>{{cite web|title=Proceedings August 2011 Vol. 137/8/1,302 : Page 18|url=http://www.bluetoad.com/publication/index.php?i=76221&m=&l=&p=20&pre=&ver=swf|website=bluetoad.com|publisher=USCG|access-date=2017-02-12|archive-url=https://web.archive.org/web/20170213163922/http://www.bluetoad.com/publication/index.php?i=76221&m=&l=&p=20&pre=&ver=swf|archive-date=2017-02-13|url-status=live}}</ref> The cutter's weapons, command and control suite can be upgraded and is hardened to survive potential attacks and process increased data flow.<ref name=GS-NSC/>

[[File:Bertholf, Navy ship formation A 110617-G-RS249-003.jpg|thumb|''Bertholf'' underway in formation with the Navy during [[Exercise Northern Edge]], 2011]]

The first NSC, {{USCGC|Bertholf|WMSL-750|6}}, entered [[sea trial]]s in February 2008.<ref>{{cite web |url=https://www.flickr.com/photos/coastguardnews/2259987590/ |title=Bertholf Sea Trials on Flickr |archive-url=https://web.archive.org/web/20170213085318/https://www.flickr.com/photos/coastguardnews/2259987590/ |archive-date=2017-02-13 |work=[[Coast Guard News]] |date=February 11, 2008 |via=[[Flickr]]}}</ref> She has been in service since August 2008, and is based at [[Coast Guard Island]], [[Alameda, California]]. A second NSC, {{USCGC|Waesche|WMSL-751|2}}, is alsowas based in Alameda in 2010.<ref>{{cite web|url=http://www.uscg.mil/acquisition/|title=Acquisition Directorate (CG-9)|website=www.uscg.mil|access-date=2008-06-17|archive-url=https://web.archive.org/web/20080614230057/http://www.uscg.mil/acquisition/|archive-date=2008-06-14|url-status=live}}</ref> Construction of {{USCGC|Stratton|WMSL-752|2}}, which now carries a crew of 123, began in 2008 at Huntington Ingalls Shipyard in Pascagoula. The vessel was christened by first lady Michelle Obama on 23in July 2010, and releaseddelivered to the custody of the Coast Guard on 2in September 2011.<ref>{{cite web|url=http://www.hometownannapolis.com/news/top/2011/11/01-24/New-Coast-Guard-Cutter-visits-Annapolis.html|title=Real Estate|access-date=2011-11-01|archive-url=https://web.archive.org/web/20120406172256/http://www.hometownannapolis.com/news/top/2011/11/01-24/New-Coast-Guard-Cutter-visits-Annapolis.html|archive-date=2012-04-06|url-status=live}}</ref> She is now in service in Alameda. Construction on the fourth NSC, {{USCGC|Hamilton|WMSL-753|2}}, began in 2011. She was delivered to the Coast Guard in September 2014. The

In December 2009, a fleet mix analysis phase- study in December 2009 called for nine NSCs,.<ref>O'Rourke (31 Oct 12), page 26</ref> but eightEight ships are in the [[Program of Record]],. and only sevenSeven hulls have beenwere funded as of the FY2013-2017 capital investment plan.<ref name=CRS20121031 /> The NSCs proved their capability to perform naval operations during the 2012 [[Exercise RIMPAC#RIMPAC 2012|RIMPAC exercises]], where the ''Bertholf'' detected and tracked missile threats and also provided naval gunfire support for troops ashore during the training exercise, demonstrating the capability of moving with other naval forces and being able to perform other defense operations.<ref>{{cite web|title=National Security Cutters Demonstrate Capabilities|url=https://www.defensemedianetwork.com/stories/national-security-cutters-demonstrate-capabilities/3/|website=DefenseMediaNetwork.com|publisher=Mark Faram, Defense Media Network|access-date=12 February 2017|archive-url=https://web.archive.org/web/20170213001533/https://www.defensemedianetwork.com/stories/national-security-cutters-demonstrate-capabilities/3/|archive-date=13 February 2017|url-status=live}}</ref>

On 7In July 2009, the [[Government Accountability Office]] reported that delays in the NSC program are likely to result in "the loss of thousands of cutter operational days for conducting missions through 2017."<ref>[http://www.gao.gov/products/GAO-09-810T "Coast Guard: Observations on the Fiscal Year 2010 Budget and Related Performance and Management Challenges"] {{Webarchive|url=https://web.archive.org/web/20090708194957/http://www.gao.gov/products/GAO-09-810T |date=2009-07-08 }} July 7, 2009 ''[[GAO]]''</ref> The GAO also reported that month that problems in the NSC program havehad delayed the OPC program by five years.<ref>{{cite web|url=http://www.cbo.gov/doc.cfm?index=10460|title=Options for Combining the Navy's and the Coast Guard's Small Combatant Programs|work=Congressional Budget Office|date=July 17, 2009|access-date=2009-07-19|archive-url=https://web.archive.org/web/20090723222019/http://www.cbo.gov/doc.cfm?index=10460|archive-date=2009-07-23|url-status=live}}</ref> The program was also plagued by structural issues;. theThe Coast Guard historically uses its cutters extensively, typically 180 days at sea a year,. furthering the problem this will often beOperations in North Pacific and North Atlantic waters that are some of the roughest seas in the Northern Hemisphere. As such, the stressesStresses on the cutters are expected to be very severe. Structural analysis showed that some parts of the cutter could be expected to survive only 3 years. This has beenwas addressed in cutter 752 ononwards, with the first two cutters receiving reinforcements later.<ref>{{cite web|url=http://www.globalsecurity.org/military/systems/ship/nsc-structure.htm|title=National Security Cutter (NSC) Maritime Security Cutter, Large (WMSL)|author=John Pike|access-date=2011-08-21|archive-url=https://web.archive.org/web/20120515100104/http://www.globalsecurity.org/military/systems/ship/nsc-structure.htm|archive-date=2012-05-15|url-status=live}}</ref> WMSL-752, the ''Stratton'', suffered corrosion and leaks within weeks of commissioning in 2012. Earlier ships have not had that problem, so it may be the result of the [[cathodic protection]] system being hooked up in reverse. The first NSC, the ''Bertholf'', has had structural enhancements put into place to fix reports of fatigue life issues; the second NSC, ''Waesche'', had structural enhancement work completed in September 2018. The cutter ''Stratton'' and all subsequent NSCs have the enhancements already installed.<ref>{{cite web|title=Structural Enhancement Work To Begin On Second NSC, Conclude On First|url=http://www.dcms.uscg.mil/Our-Organization/Assistant-Commandant-for-Acquisitions-CG-9/Newsroom/NSC_091217/|website=www.dcms.uscg.mil|publisher=United States Coast Guard|access-date=23 February 2018|archive-url=https://web.archive.org/web/20171020220229/http://www.dcms.uscg.mil/Our-Organization/Assistant-Commandant-for-Acquisitions-CG-9/Newsroom/NSC_091217/|archive-date=20 October 2017|url-status=live}}</ref><ref>{{cite news |title=USCG Waesche structurally enhanced |url=https://www.shephardmedia.com/news/imps-news/structural-enhancement-work-concluded-second-nsc/ |access-date=6 September 2018 |archive-url=https://web.archive.org/web/20180905183150/https://www.shephardmedia.com/news/imps-news/structural-enhancement-work-concluded-second-nsc/ |archive-date=5 September 2018 |url-status=live }}</ref> The NSC program originally encountered problems meeting [[Tempest (codename)|TEMPEST]] requirements, but after more recent testing, the first NSC, ''Bertholf'', passed all TEMPEST requirements.<ref>{{cite web|title=SHAPING A 21ST CENTURY USCG: THE KEY ROLE FOR MARITIME PATROL AIRCRAFT|url=http://www.sldinfo.com/shaping-a-21st-century-uscg-the-key-role-for-maritime-patrol-aircraft/|website=www.sldinfo.com|date=April 19, 2011|access-date=14 November 2017|quote=The first National Security Cutter, USCGC BERTHOLF, has passed all TEMPEST and information assurance requirements culminating in the authority to operate|archive-url=https://web.archive.org/web/20171115015146/http://www.sldinfo.com/shaping-a-21st-century-uscg-the-key-role-for-maritime-patrol-aircraft/|archive-date=15 November 2017|url-status=live}}</ref><ref>{{cite web|title=NSC gets TEMPEST certification, much needed modernization moves forward|url=http://coastguard.dodlive.mil/2009/06/nsc-gets-tempest-certification-cg-modernization-moves-forward/|website=coastguard.dodlive.mil|access-date=14 November 2017|archive-url=https://web.archive.org/web/20170214163106/http://coastguard.dodlive.mil/2009/06/nsc-gets-tempest-certification-cg-modernization-moves-forward/|archive-date=14 February 2017|url-status=live}}</ref>

[[File:U.S. and Turkey In-Flight Engagements.jpg|thumb|USCGC ''Hamilton'' and [[TCG Turgutreis (F-241)|TCG ''Turgutries'']] in the [[Black Sea]], 30 April 2021]]

Patrol Frigate 4501 is very similar to the NSC, the main differences being a modified stern ramp<ref name=Mazumdar20120424>{{cite web | url=http://www.defensemedianetwork.com/stories/patrol-frigate-concepts-from-huntington-ingalls-industries-gain-traction-internationally/ | title=Patrol Frigate Concepts from Huntington Ingalls Industries Gain Traction Internationally | first=Mrityunjoy | last=Mazumdar | date=24 April 2012 | publisher=Defense Media Network | access-date=9 February 2013 | archive-url=https://web.archive.org/web/20130201141521/http://www.defensemedianetwork.com/stories/patrol-frigate-concepts-from-huntington-ingalls-industries-gain-traction-internationally/ | archive-date=1 February 2013 | url-status=live }}</ref> and a [[knuckle boom crane]] replacing the overhead crane.<ref name=JDW20120425>{{cite journal | first=Geoff | last=Fein | title=HII seeks exports for redesigned NSC | journal=Jane's Defence Weekly | page=8 | date=25 April 2012 | url=http://in.zinio.com/reader.jsp?issue=416219991&o=int&prev=sub&p=8 | access-date=9 February 2013 | archive-url=https://web.archive.org/web/20160303224754/http://in.zinio.com/reader.jsp?issue=416219991&o=int&prev=sub&p=8 | archive-date=3 March 2016 | url-status=live }}</ref> The crew is increased to 148,.<ref name=Mazumdar20120424 /> and itIt was offered to the U.S. Navy as a replacement for the [[Littoral Combat Ship]];.<ref name=JDW20120425 /> theThe FY13 cost of an LCS was $446.3{{nbsp}}million compared to $735{{nbsp}}million for an NSC.<ref>O'Rourke (31 Oct 12), pages 4 & 51</ref>

Patrol Frigate 4921 is a more radical redesign with a crew of 141,<ref name=Mazumdar20120424 /> adding weapons and sensors at the expense of reducing range from {{convert|12000|to|8000|nmi|km}}.<ref name=JDW20120425 /> It adds a 12-cell [[RIM-162 ESSM#Mk 56|Mk 56 VLS]] launcher for [[RIM-162 ESSM|ESSM]] air-defense missiles, just behind the main gun, which is upgraded from 57&nbsp;mm to a [[76mm Super Rapid naval cannon|76&nbsp;mm Super Rapid]].<ref name=Mazumdar20120424 /> Two quad launchers for [[Harpoon (missile)|Harpoon]] anti-ship missiles and a [[Mark 32 Surface Vessel Torpedo Tubes|triple launcher]] for torpedoes are added to the stern.<ref name=JDW20120425 /> It retains the SeaRAM/[[Phalanx CIWS]] and 6 machine guns of other NSC variants.<ref name=Mazumdar20120424 /> The stern is closed in and houses a towed-array sonar;.<ref name=JDW20120425 /> aA hull sonar is installed for mine countermeasures and an ESM suite.<ref name=JDW20120425 /> The original "National Patrol Frigate" concept had an [[AN/SPY-1]]F air-defense radar.<ref>{{cite web | url=http://www.dodbuzz.com/2011/04/13/the-phantom-frigate/ | title=The phantom frigate | first=Philip | last=Ewing | date=13 April 2011 | publisher=Military Advantage (DODbuzz) | access-date=13 April 2011 | archive-url=https://web.archive.org/web/20110417142530/http://www.dodbuzz.com/2011/04/13/the-phantom-frigate/ | archive-date=17 April 2011 | url-status=live }}</ref> but byBy 2012 the PF 4921 was being shown with an Australian [[CEA Technologies|CEAFAR]] radar.<ref name=Mazumdar20120424 />

Brazil, Saudi Arabia, and Germany have also shown interest in NSC derivatives.<ref name=Mazumdar20120424 />

|Long Lead Time Materials (LLTM) funded as Option for 12th ship;.<ref name= "Sep2022_rpt_procure"/> LLTM contract not yet awarded;.<ref name= "USCG_NSC_program"/> $300,000,000 is authorized for a twelfth National Security Cutter.<ref name="2023_NDAA">{{cite web |url=https://www.congress.gov/bill/117th-congress/house-bill/7776/text|title=James M. Inhofe National Defense Authorization Act for Fiscal Year 2023}}</ref> USCG has not exercised option, as of March 2023.<ref name= "2023_USCG_rpt2congress"/>

File:USCG long range interceptor aboard Bertholf.jpg|LongA long range interceptor aboard the cutter ''Bertholf''