Question: Who builds ships for the US Navy?

Huntington Ingalls Industries


Huntington Ingalls Industries (HII) is an American Fortune 500 shipbuilding company formed on March 31, 2011 as a spin-off of Northrop Grumman.[4] It is the largest military shipbuilder in the United States, with its main shipyard located in Newport News.[5]
Mike Petters is currently the president and CEO of Huntington Ingalls Industries (formerly president of the Newport News shipyard and president of the Northrop Grumman Shipbuilding).[6]
HII is the sole designer, builder, and refueler of nuclear-powered aircraft carriers in the United States. It is one of two nuclear-powered submarine builders (the other being General Dynamics Electric Boat). 70% of the current, active U.S. Navy surface fleet has been built by HII's former units.[7]
History

Huntington Ingalls Industries was formerly known as Northrop Grumman Shipbuilding (NGSB), created on January 28, 2008 by the merger of Northrop Grumman's two shipbuilding sectors, Northrop Grumman Ship Systems and Northrop Grumman Newport News. The company takes its name from the founders of its two main facilities: Collis Potter Huntington (Newport News) and Robert Ingalls ([Pascagoula).
Divisions
Newport News Shipbuilding, Newport News, Virginia (nuclear aircraft carriers, submarines, refueling and complex overhaul, carrier inactivation)
Ingalls Shipbuilding, Pascagoula, Mississippi (surface combatants, amphibious warships, Coast Guard large cutters)
Technical Solutions, (US Navy Fleet Support, Integrated Mission Solutions, DoE Nuclear & Environmental, Oil & Gas)
Subsidiaries of Technical Solutions
AMSEC, Virginia Beach, Virginia (provides maintenance, modernization, logistics, engineering, IT, and training solutions for the U.S. Navy)
Continental Maritime of San Diego, San Diego, California (Master Ship Repair Contractor for the U.S. Navy and provider of services to Military Sealift Command.)
Newport News Industrial, Newport News, Virginia (provides fabrication, construction, equipment repair, technical services and products to the energy and petrochemical industries as well as government customers.)
Stoller Newport News Nuclear (SN3), Broomfield, Colorado (a full-service nuclear operations and environmental services company focused on U.S. Department of Energy (DOE) and U.S. Department of Defense (DoD) clients.)
Undersea Solutions Group, Panama City Beach, Florida (a leading designer and builder of unmanned underwater vehicles for domestic and international customers.)
UniversalPegasus International (UPI), Houston, Texas (provides project management, engineering and construction management for the energy industry.)
Former Camber Corporation, Virginia Beach, Virginia and Huntsville, Alabama (provider of Agile software engineering & IT solutions; all hazards services; modeling, simulation and training solutions and services; unmanned aerial systems support; intelligence analysis and operations; and engineering and management services to DoD, Federal and commercial customers.)[8]
Facilities
HII operates facilities in several key locations across the US:
Newport News Shipbuilding, Newport News, Virginia (nuclear aircraft carriers, submarines, overhaul)
Ingalls Shipbuilding, Pascagoula, Mississippi (surface combatants, amphibious assault ships, Coast Guard large cutters)
Virginia Beach, Virginia (AMSEC, fleet support)
San Diego, California (Continental Maritime, fleet repair and support)
Former facilities
Gulfport, Mississippi (composite R&D, composite components)
Tallulah, Louisiana (components and subassemblies, closed in 2011)[9]
Waggaman, Louisiana (closed in 2011)[9]
Avondale Shipyard, New Orleans, Louisiana (amphibs, auxiliaries, closed in October 2014)[6]
Projects
HII's 2016 order backlog amounts to $20.5 billion.[10]
Gerald R. Ford-class aircraft carriers
HII is to build ten Gerald R. Ford-class aircraft carriers for the US Navy. It is scheduled to deliver one carrier every five years starting in 2015.[11]
America-class amphibious assault ship
The US Navy awarded HII a $2.4 billion fixed-price incentive contract for the detail design and construction of the amphibious assault ship America (LHA-6), the lead ship of her class. Work was performed primarily at the company's shipyard in Pascagoula, Miss.[12]
In June, 2016 Huntington Ingalls Industries has been awarded a $273 million contract to build the U.S. Navy’s newest amphibious assault warship, according to a company press release. The total contract value for the construction of the third America-class ship is over $3 billion. This contract included planning, advanced engineering and procurement of long-lead material for the new vessel.[13]
San Antonio-class amphibious transport dock
In April 2011, the US Navy awarded HII a $1.5 billion contract for the construction of John P. Murtha (LPD-26), the tenth of the San Antonio-class amphibious transport docks.[14] 
This was the first Navy contract awarded to HII, though Ingalls Shipbuilding had already built three ships of the class.
Virginia-class attack submarines
The US Navy is building Virginia-class submarines as replacements for the Los Angeles-class submarines which are currently being phased out.
HII, under an industrial arrangement with General Dynamics Electric Boat (the only other shipyard capable of building nuclear-powered submarines), solely builds the stern, habitability and machinery spaces, torpedo room, sail and bow, while Electric Boat solely builds the engine room and control room.  HII and Electric Boat alternate work on the reactor plant, final assembly, test, outfit and delivery.
Offshore Patrol Cutter
In 2014 The Government Accountability Office denied a contract appeal by Ingalls for the US Coast Guard's Offshore Patrol Cutter program, finding that the USCG's ranking of the shipyard to be marginal was justified.[15]