Key point: A submarine vs and undersea mountain. What could go wrong?
In 2005, a U.S. Navy attack submarine collided head-on with an undersea mountain at more than thirty miles an hour. Despite the damage the ship sustained and the crew’s injuries, the USS San Francisco managed to limp to her home port of Guam on her own power. The incident was a testament to the design of the submarine and the training and professionalism of her crew.
USS San Francisco is a Los Angeles-class nuclear attack submarine. Submarine builder Newport News Shipyard began construction on her in 1977, and she was commissioned on April 24, 1981. The submarine joined the U.S. Pacific Fleet and served there throughout her career.
Like all Los Angeles subs, she displaced 6,900 tons submerged, was 362 feet long, and had a beam of 33 feet. A General Electric PWR S6G nuclear reactor provided 35 thousand shipboard horsepower, driving the submarine to a speedy 33 knots. A typical crew consisted of 129 officers and enlisted men.
On January 8, 2005, the USS San Francisco was traveling at flank (full) speed—approximately 38 miles an hour at a depth of 525 feet. She was 360 miles southeast of Guam heading to Brisbane, Australia for a liberty stop. Navigation plotted the route based on undersea maps that were generally agreed to give the most complete view of the seabed. According to The New York Times, the captain went to lunch and the navigation officer, believing it was safe to do so, dived the sub from 400 to 525 feet and accelerated to flank speed.
At approximately 11:42 local time, while transiting the Caroline Islands mountain chain, the submarine came to an abrupt—and unexpected—halt. There was a shudder and then a tremendous noise. Men throughout the ship were thrown from their stations against their surroundings. In an instant many suffered bruises, lacerations, broken bones and fractures. A chief petty officer described the scene as looking like a “slaughterhouse”, with blood running everywhere. Ninety eight crewmen were injured with one, Machinist's Mate Second Class Joseph Allen Ashley, fatally injured.