U.S.S. Sailfish Sinks

On 12 May, following a yard overhaul, Squalus began a series of test dives off Portsmouth, New Hampshire.

After successfully completing 18 dives, she went down again off the Isles of Shoals on the morning of 23 May.42°53′N 70°37′W Failure of the main induction valve caused the flooding of the aft torpedo room, both engine rooms, and the crew's quarters, drowning 26 men immediately. Quick action by the crew prevented the other compartments from flooding. Squalus bottomed in 243 ft (74 m) of water.

On 23 May 1939, while conducting a test dive off Portsmouth, NH, Squalus sank in 243 feet of water when the engine room flooded through the main induction. The 26 men in the after part of the ship were drowned. Thirty-three others, including the commanding officer, LT Oliver F. Naquin, who were in the forward section, were left with the problem of getting to the surface.

The USS Squalus was conducting test dives off Portsmouth, New Hampshire when she flooded and struck bottom on May 23, 1939, killing 26 men. The submarine was located by the USS Sculpin, allowing the submarine rescue ship USS Falcon to send down divers to rescue the remaining 33 survivors of the crew. Four of the divers received the Medal of Honor for the rescue.