Background
The origin of the Los Angeles (SSN 688) class go back to the late-1960s when the U.S. Navy considered a requirement for a high-speed attack and ASW submarine to cover the threat of Russian SSGNs hitting the carrier battle groups. The result of that study has been one if the most sofisticated and expensive, but very effective and importat weapons system ever have attained opertional status, and one which will eventually number no less than 62 boats. The Los Angeles class submarines are 68 ft. longer than the previous Sturgeon class and the hull is optimized for high submerged speed, with a very small sail.The first-of-class USS Los Angeles (SSN 688) was comissioned on 13th November -76, since when building has continued at a steady rate; the 62nd and last-of-class was comissioned in August -96.
As initially built, the forward hydroplanes are mounted on the sail, limiting the ability of those boats so fitted to penetrate the ice in Arctic waters. However, from USS San Juan (SSN 751) onwards, the planes have been moved forward to the more traditional bow position and, together with some new electronic equipment, this enables them to be formally declared "Arctic capable". These boats are refered to as 688I(for Improved).
The Most remarkable feature of the Los Angels class is its armament. These powerful submarines are armed with Harpoon and Tomahawk missiles, as well as conventional and wire-guided torpedoes. From USS Providence (SSN 719) onwards they are also equipped with 12 vertical launch tubes, which enables Tomahawks to be carried without reducing the quantity of other weapons carried internally. During their service these submarines have carried out many remarkable feats, one of them being circumnavigation of the globe, totally submerged, by USS Groton (SSN 694), between 4th April and 8th October 1980. Several of them also fired Tomahawk missiles whilst submerged against targets deep in Iraq during the Gulf War of 1991.
Source:The New Illustrated Guide to Modern Warships by Tony Gibbons & David Miller.