The Los Angeles class (also known as the 688 class) is a class of nuclear-powered fast attack submarines (SSN) in service with the United States Navy. They represent two generations and close to half a century of the U.S. Navy's attack submarine fleet. As of 2016, 36 of the class are still in commission and 26 retired from service. Of the 26 retired boats, 14 of them were laid up half way (approximately 17–18 years) through their projected lifespans due to their midlife reactor refuelings being cancelled. A further four boats were proposed by the Navy, but later cancelled. The class has more operating nuclear submarines than any other in the world. All submarines of this class are named after American towns and cities (e.g., Key West, Florida, and Greeneville, Tennessee), the exception being USS Hyman G. Rickover (SSN-709). This system of naming broke a long-standing tradition in the U.S. Navy of naming attack submarines for creatures of the ocean (e.g., USS Nautilus (SSN-571)).
In 1982 after building 31 boats, the class underwent a minor redesign, the following 8 that made up the second "flight" of subs had 12 new vertical launch tubes that could fire Tomahawk missiles. The last 23 saw a significant upgrade with the 688i improvement program. These boats are quieter, with more advanced electronics, sensors, and noise reduction technology. Externally they can be recognized quickly as the retractable diving planes are placed at the bow rather than on the sail....LESS