A diving bell was dropped by the rescue ship Falcon to reach survivors of the sunken submarine Squalus.
Early in the morning on May 23, 1939, the state-of-the-art diesel electric submarine USS Squalus was conducting a test dive off the Isle of Shoals when a catastrophic valve failure caused the sub to sink to 240 feet. Due to the extreme depth and difficulty of the rescue attempt, the search was called off until the next day, as the 33 passengers watched the crew compartment, engine and torpedo rooms flood with water.
At 11:30 a.m. on May 24, searchers sent down a McCann rescue chamber, a more sophisticated version of a diving bell and, after a few mishaps, hauled all 33 trapped victims to safety in 13 hours.
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