On Feb 8, 1980 one of the last diesel-electric submarine in the Atlantic fleet of the US Navy was retired. That boat was the USS Tang, and it had served the Navy for almost 30 years, an incredible length of time for a submarine.
The first USS Tang (SS 306) was sunk in 1944 in the Straits of Formosa by its own torpedo after only a year at sea. During an attack on a Japanese convoy, a torpedo that the Tang fired went wild and sunk the boat, with almost all of the crew dying.
Seven years later, the new USS Tang (SS 563) was launched, the first of the modern fast attack submarines. This new boat incorporated several new concepts, including a streamlined hull, integrated snorkel system, increased speed and depth, and total submergence operation. The boat set a depth record on its first deep dive, despite a fire in the pumproom.
For twenty years the Tang conducted a full range of assignments, including 11 Western Pacific deployments, 18 special missions including the initial polar exploration for the Nautilus' Trans-Polar voyage, and four Vietnam patrols. The Tang's crew had great pride in their boat, and the submarine consistently won awards and recognition, even serving as the flagship of the Commander U.S. Pacific Fleet Submarine Force.
New designs and technology sprang up during that 20 years, and the Tang incorporated much of it. Perhaps the most amazing change the Tang underwent was two "hull stretches" where the boat was literally cut in half and a new section added to the middle. After undergoing these stretches the boat was 600 tons heavier and more than 22 feet longer than when it was launched in 1951.
In 1972, the Tang was reassigned to a new home port San Diego, and had a new mission: antisubmarine warfare (ASW) research and training. It served there for 6 years, then was moved to New London, Conn., where the 563 was redesignated "SS" and became the only operational diesel submarine in the Atlantic Fleet and was once again heavily used in ASW training.
After retiring from the US Navy in 1980, the Tang it began a new career with the Turkish Navy as the First modern class U.S. submarine in their navy. It is still being used there to this day, after more than 50 years under the sea.