USS Guitarro ( SSN - 665 ) USS " Guitarro " ( SSN - 665 ) , a , was the second ship of the United States Navy to be named for the guitarro , a ray of the guitarfish family . Construction and commissioning . Keel - laying and launching . The contract to build " Guitarro " was awarded to Mare Island Naval Shipyard at Vallejo , California , on 18 December 1964 and her keel was laid down there on 9 December 1965 . She was launched on 27 July 1968 , sponsored by Mrs . John M . Taylor . Sinking . On 15 May 1969 , " Guitarro " was moored in the Napa River at Mare Island Naval Shipyard while construction was still underway . At about 16 : 00 , a civilian nuclear construction group began an instrument calibration assignment which required the filling of certain tanks , located aft of the ships pivot point , with approximately five tons of water . Within 30 minutes , a different , non - nuclear civilian construction group began an assignment to bring " Guitarro " within a half - degree of trim ; this entailed the adding of water to tanks forward of the ships pivot point to overcome a reported two - degree up - bow attitude . Until shortly before 20 : 00 , both groups continued to add water , unaware of each other ' s activities . Twice between 16 : 30 and 20 : 00 , a security watch advised the non - nuclear group that " Guitarro " was riding so low forward that the 1 . 5 - foot - high ( 0 . 46 m ) wakes of boats operating in the Napa River were sloshing into an uncovered manhole in the most forward and lowest portion of the ship ' s deck ; these warnings went unheeded . At 19 : 45 , the non - nuclear group stopped adding water to the ballast tank s and began to halt work for their meal break , leaving at 20 : 00 . At 19 : 50 , the nuclear group completed their calibrations and began to empty the tanks aft . At 20 : 30 , both the nuclear group , still aboard , and the non - nuclear group , returning from their break , noticed " Guitarro " taking a sudden down angle which put the forward hatches underwater . Massive flooding took place through several large open hatches . Efforts between 20 : 30 and 20 : 45 to close watertight doors and hatches were largely unsuccessful because lines and cables ran through the doors and hatches , preventing them from closing . At 20 : 55 , " Guitarro " sank earning her the nickname " Mare Island Mud Puppy " . " Guitarro " was refloated three days later , on 18 May 1969 . Damages to her were estimated at between 15 . 2 million USD and 21 . 85 million USD . Commissioning . " Guitarro " had been scheduled to be commissioned in January 1970 , but repairs necessitated by her sinking dictated a 32 - month delay . She finally was commissioned on 9 September 1972 with Commander Gordon Lange in command . Service history . In the mid - to - late 1970s , " Guitarro " was stationed at Point Loma in San Diego , California , commanded by Alvin H . Pauole , followed by Scott Van Hoften . She was active at the time in the pre - operational testing of the new Tomahawk cruise missile , launching several of the missiles on a test range off the coast of Southern California . Decommissioning and disposal . " Guitarro " was decommissioned on 29 May 1992 and stricken from the Naval Vessel Register the same day . Her scrapping via the Nuclear - Powered Ship and Submarine Recycling Program at Puget Sound Naval Shipyard in Bremerton , Washington , was completed on 18 October 1994 .