ship. The submarine suffered external damage to the sail and superstructure. After local repairs at the submarine squadron facilities in Rota, she reported to Groton, Connecticut, for more detailed repairs at the Electric Boat Division of General Dynamics Corporation, after which she resumed deterrent patrols out of Rota. This incident was revisited, when , on 9 February 2001, also conducted an emergency main ballast tank blow off the coast of Oahu while hosting several civilians. Greeneville struck the Japanese fishery high school training ship Ehime Maru (), causing the fishing boat to sink in less than ten minutes with the death of nine crew members, including four high school students. Von Steuben had conducted an emergency main ballast tank blow due to its planes tangled in the submerged towline of the tug, jamming them so that the sub threatened to sink. Greenville blew her main ballast tanks merely to demonstrate a maneuver and not to escape from danger. Her captain consciously surrendered control of the vessel. The captain of Von Steuben had acted properly in ordering the emergency blow. He had lost control of his ship, his stern planes were jammed, and the possibility of an irreversible plunge to the bottom of the ocean was very real. However, Greenvilles captain had to face a court of inquiry and possibly a full court-martial, until his request to retire was approved. Upgraded ballistic missile system In November 1970, Von Steuben visited Groton once again, this time near the end of a 16-month overhaul during which she was modified to carry the newly developed Poseidon C-3 ballistic missile, which boasted major advances in warhead technology and accuracy and systematically was replacing the older Polaris missiles in the , James Madison and s. Von Steuben conducted post-conversion shakedown during the early months of 1971 and, while escorted by the destroyer for range security, conducted a two-missile Demonstration and Shakedown Operation (DASO) in which she fired her first and second Poseidon missiles in February and March 1971, respectively. In May 1971, she returned to Charleston and resumed strategic deterrent patrols carrying the newer Poseidon missiles. She conducted an Extended Refit Period at Portsmouth Naval Shipyard between March 1978 and May 1978. Von Steubens ballistic missile system was upgraded a second time in the early 1980s to use Trident I (C4) ballistic missiles. These missiles were also retrofitted to 11 other SSBNs of the James Madison