On may 23, 1939, the submarine 'Squalus' dived with an air intake valve open. Fifty-nine men were trapped inside and 33 were saved with a newly-developed diving bell. After four months the Squalus was raised and re-commissioned as the 'Sailfish'. It was one of the navy's worst peacetime submarine disasters until the 'Thresher' tragedy. United States Rescue ships in the Atlantic Ocean off the Coast of Portsmouth, New Hampshire on May 23, 1939. MCUS - Hard helmet diver given assistance by sailors. MLS - Sailors on the deck and standing on the side on a ledge of their navy vessel. CUS - Profile of the ships Capitan looking down at the rescue mission in effect. MS - Some of the rescue sailors coming up via a new diving bell. MCUS - Navy salvage ship and crew, bringing up the 'Squalus' for a brief moment there was some success. MS - The submarine 'Squalus' going back down into 40-fatoms of water. The nose of the submarine sticks out of the water just before it goes down again. MCUSOH - Ships officers watching the rescue attempt taking place. MS - The 'Squalus" is raised. MCUS - Sailors standing on the deck of the re-commissioned and once named 'Squalus" , now it has be re-commissioned and re-named the 'Sailfish' with four of the original crew members. MCUS - The Sailfish tied up at the dock