Unlike Most other navies, the U.S. Navy’s entire submarine fleet is nuclear-powered. Its last diesel-electric combatant was the USS Blueback (SS-581), which was in commission from October 1959 to October 1990.
Officially, the Navy has three classes of fast-attack submarines (SSNs)—Los Angeles, Seawolf, and Virginia. But the actual number is trickier. Boats from two of the three Los Angeles–class “flights” are still in commission, along with both variants for the Seawolfs, and four “blocks” of the Virginias (with a fifth under construction).
The larger of the three Seawolfs, the Jimmy Carter (SSN-23), is unique, dedicated mainly to covert missions. And the four Ohio-class guided-missile submarines—SSGNs—have a mission that arguably encroaches on the SSNs’.
As for weapons, all the SSNs in commission carry Mk 48 Advanced Capability torpedoes and Tomahawk strike missiles. The Seawolf- and Los Angeles–class submarines also can launch Harpoon antiship missiles. The Virginia and Los Angeles classes have vertical launch capabilities, but the
Seawolf does not.
Los Angeles Class
Flight I
Commissioned from 1976 to 1985
SSN-688 to -718 (No Flight I submarines remain in commission.)
Note the fairwater planes on the sail. Such planes do not need to be stored or folded to come alongside piers, tenders, or other ships, but the midship location demands a large surface area to manage pitch.
Flight II
Commissioned from 1985 to 1989
SSN-718 to -725 and -750 (Only the final two Flight II subs remain in commission.)
The second flight is similar to Flight I but with the addition of 12 vertical-launch tubes forward of the sail. During the 1991 Gulf War, the USS Louisville (SSN-724) became first U.S. submarine to launch Tomahawk missiles in combat while submerged.
Flight III
(also called 688i or improved Los Angeles class)
Commissioned from 1990 to 1996
SSN-751 to -773 (Most Flight III submarines remain in commission.)
The Flight IIIs replace fairwater planes with retractable bow planes, which can be smaller because of their placement far forward of ship’s center of flotation.
Virginia Class
Block I
Commissioned 2004 to 2008
SSN-774 to -778
Block II
Commissioned 2008 to 2013
SSN-779 to -783
Block III
Commissioned 2014 to 2020
SSN-784 to -791
The Virginia class is the first to use
optronic periscopes exclusively.
In April 2020, the USS Delaware
(SSN-791) became the first Navy
ship commissioned underway and
underwater, because of the COVID-19 pandemic.
Block IV
Commissioned 2020 to 2024
SSN-792 to -796
Building and Authorized
Future Block IV
Under Construction
SSN-797 to -801
Block V
Under construction, authorized,
and announced
SSN-802 to -811
Notes on Block V Names
Many of the first tranche of Block V boats’ names evoke famous combatants of World War II. SSN-802 (Oklahoma) and -803 (Arizona) are named for battleships lost at Pearl Harbor, Hawaii, on 7 December 1941. The fish names given to SSNs -804 (Barb), -805 (Tang), -806 (Wahoo), and -807 (Silversides), honor four submarines that were among the most successful hunters of the Pacific War. And the Long Island (SSN-809) will share a name with the first escort carrier—CVE-1—which served throughout World War II in both theaters.
The future San Francisco (SSN-810) and Miami (SSN-811) will be named for Los Angeles–class submarines that were badly damaged in service. The previous San Francisco (SSN-711) collided with a seamount on 8 January 2005, but she returned to active service in 2008. In 2022, she was decommissioned and has been converted to a moored training ship. The Miami (SSN-755) was destroyed by fire at Portsmouth Naval Shipyard in Kittery, Maine, in May 2012. A shipyard worker was convicted of arson after he confessed to setting the fire so his work shift could end early.
And SSN-808 will be named for John H. Dalton, who was Secretary of the Navy when construction of the first four Virginia-class submarines was authorized.
Seawolf Class
Originally to be a 29-ship replacement for the Los Angeles class, the Seawolf program grew too expensive and complex and was canceled after only three boats: USS Seawolf (SSN-21), Connecticut (SSN-22), and Jimmy Carter (SSN-23).
The Jimmy Carter is longer than the other two thanks to her Multi-Mission Platform, a 100-foot-long plug—sometimes described as a hangar—for vehicles, divers, and weapons. Often referred to as the “special projects submarine,” the Jimmy Carter is used for covert missions.
