Following her commissioning on March 1, 1939, the submarine SQUALUS (SS-192) began a series of test dives out of Portsmouth Navy Yard on 12 May. After successfully completing 18, SQUALUS made final preparations for her fateful dive near the Isles of Shoals at 0835 on the morning of the 23rd. The commanding officer of SQUALUS, Lieutenant Oliver F. Naquin, initially thought the dive, as he later recalled, was “going to be a beauty”. However, nearly simultaneous reports of flooding from both engine rooms initiated a relentless descent to the bottom that the best efforts of the crew could not arrest. As the men worked to close watertight doors and ventilation flappers, the submarine compartment lights went out soon followed by the emergency lighting. Hand lanterns soon provided the only illumination available to the men trapped on the ocean floor. At 0845, Lieutenant Naquin ordered that the first of a series of red smoke rockets be fired and that the torpedo room marker buoy be released.
When the stricken submarine failed to provide a surfacing report, Rear Admiral Cyrus W. Cole, Commandant of Portsmouth Navy Yard, directed her sister ship SCULPIN (SS-191), due to set sail from Portsmouth for Newport at 1130, to search for the missing boat. At 1241, SCULPIN sighted red smoke and soon picked up the forward marker buoy by which she briefly communicated with SQUALUS by telephone until the buoy cable snapped. At 0425 the next morning, the submarine rescue ship FALCON (ASR-2) reached the scene and began preparations for rescue operations. Minutes before, Commander Allan R. McCann, USN, and 12 divers from the Experimental Diving Unit arrived in the area. The Officer in Charge of Experimental Diving at the Washington Navy Yard, Lieutenant Commander Charles B. Momsen, USN, would also be instrumental in the rescue of the crew and the salvage of SQUALUS. The rescue chamber that McCann and Momsen had helped develop for the Navy was about to take center stage.
The tragic loss of life that resulted from the sinking of the submarine S-4 (SS-109) in December 1927, spurred the Navy to look for technology capable of retrieving trapped submariners. Momsen conceived of a rescue chamber and continued to refine this idea in reaction to testing and experimentation until he was assigned the task of developing an individual breathing apparatus, nicknamed the “Momsen Lung”. From July 1929 to July 1931, McCann, during his tenure at the Bureau of Construction and Repair, further developed the escape apparatus that would be known as the McCann Rescue Chamber. While in command of the Experimental Diving Unit at the Navy Yard, Momsen also proposed a helium and oxygen mixture that would be used by the divers involved in the SQUALUS operation. The work of both men prior to and during the rescue and salvage proved crucial.
By 1212 on the 24th, the rescue chamber made contact with SQUALUS and 28 minutes later had been securely attached to the submarine. After providing provisions to the crew of SQUALUS, the rescue chamber took on seven survivors who reached the surface at 1342. The rescue chamber continued to operate as designed as it evacuated nine more men from SQUALUS in each of her next two trips. However, during the fourth trip to gather up the last eight survivors, including Lieutenant Naquin, the downhaul wire jammed 150 feet from the surface. Divers, at great personal risk, entered the dark and frigid waters to cut the downhaul wire. The chamber admitted water ballast to achieve negative buoyancy and it sank to the bottom before the crew of the FALCON hauled the rescue chamber to the surface by hand. The last survivors from SQUALUS left the chamber at 0025 on the 25th after a harrowing ascent of nearly four hours. A final, unsuccessful, attempt was made to find survivors beyond the 33 who had already been saved, but all the aft compartments had been completely flooded. In all, one officer, 23 sailors and two civilians had perished.
In September 1939, in a considerable technological feat, the Navy raised SQUALUS. The submarine was recommissioned as SAILFISH (SS-192) on May 15, 1940 and earned nine battle stars and a Presidential Unit Citation during World War II service.