US Navy submarine USS Seawolf during sea trials, July 10, 1997.
Improvements to Soviet subs in the 1980s prompted the US Navy to pursue its own more advanced subs.
Work on the Seawolf-class submarines got underway in the mid-1980s, but the USSR’s demise upended those plans.
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There are only three of them.
Late in the 1950s, the Soviet Navy’s nuclear-powered submarines – starting with the November-class attack submarine – could dive twice as deep as most of their American counterparts and often had higher maximum speed. But they had a conspicuous flaw: they were a lot noisier.
That meant American subs were routinely detecting and trailing the Soviet submarines from a distance without being detected in return – a huge advantage had there ever been a conflict.
In the 1980s, however, the Soviet Navy began to improve its acoustic stealth game. The Japanese Toshiba and Norwegian Kongsberg firms had sold propeller-milling technology to the Soviets that allowed for a much quieter seven-bladed propeller on its new Akula-class attack submarines.
US Navy studies concluded the Akula exceeded the mainstay of the US submarine force, the Los Angeles class, for acoustic stealth and roughly matched the Improved Los Angeles variant. As the Pentagon was flush with money during the Reagan administration, in 1983 the Navy began designing the biggest, baddest – and fastest and quietest – attack submarine possible to restore its edge over the Soviet Navy.
The resulting Seawolf laid down by Electric Boat in October 1989 had a wider hull than the 7,000-ton Los Angeles, displacing over 9,000 tons submerged and measuring 108 meters in length.
Whereas the Los Angeles carried 37 torpedoes in four tubes, the Seawolf could lug 50 heavy-weight 533-millimeter Mark 48 torpedoes or Harpoon anti-ship missiles, which it could launch through eight over-sized 660-millimeter torpedo tubes. (The tubes size was meant to future-proof in case the Navy adopted larger weapons. It didn’t.)
The Seawolf could also use the tubes to launch surface-attack Tomahawk missiles.
Officers and crew of USS Jimmy Carter in the Hood Canal on the way to Naval Base Kitsap-Bangor in Washington state.
U.S. Navy photo by Lt. Cmdr. Michael Smith
The Seawolf submarine was built entirely out of higher-strength HY-100 steel so that it could endure dives as deep as 490 meters.
Its sail (conning tower) was reinforced for operations Arctic ice, where Soviet ballistic-missile submarines were known to lurk. Moreover, its S6W pressurized water reactor gave the Seawolf an extraordinary maximum speed of 35 knots (40 mph), allowing it to chase down disengaging adversaries.
But most impressive were the Seawolf’s advancements in acoustic stealth: A Seawolf was an order of magnitude quieter than even the Improved Los Angeles boats at 95 decibels. Oceanic background noise averages 90 decibels.
Even better, the Seawolf’s propeller-less pump-jet propulsion system allowed it to maintain acoustic stealth even when cruising a brisk 20 knots, whereas most submarines are forced to crawl at 5-12 knots to remain discrete.
Its huge 7.3-meter diameter spherical sonar array on the bow was supplemented …read more
Source:: Business Insider