USS Squalus (SS-192), a diesel-electric submarine built at the Portsmouth Navy Yard, Portsmouth, New Hampshire and commissioned there on 1 March 1939, suffered a catastrophic valve failure during a test dive off the Isle of Shoals at 0740 on 23 May. Partially flooded, the submarine sank to the bottom and came to rest keel down in 40 fathoms (240 feet) of water. Navy divers and salvage ships responded quickly, and the following day began operations to rescue the surviving 32 crew members and one civilian from the forward sections of the boat. At 1130 on 24 May, USS Falcon (ASR-2) lowered the newly developed McCann rescue chamber--a revised version of a diving bell invented by Commander Charles B. Momsen--and, over the next 13 hours, all 33 survivors were rescued from the stricken submarine. On 13 September, after long and difficult salvage operations, Squalus was raised and towed into the Portsmouth Navy Yard. The boat was formally decommissioned on 15 November, renamed Sailfish on 9 February 1940, and recommissioned on 15 May 1940.
[Retrieved from USS Squalus (SS-192): The Sinking, Rescue of Survivors, and Subsequent Salvage, 1939 on November 1, 2010.]