During the month of July 1942, USS Grunion (SS-216) patrolled off Kiska Island, in the Aleutian Islands chain off Alaska, sinking two Japanese patrol boats.
On 30 July, 1942, she was ordered to the small submarine base at Dutch Harbor, nearly 600 miles to the East. Grunion never arrived and was never heard from again.
In 2002, a Japanese amateur historian provided the first solid clues about Grunion's fate:
Early in the morning of 31 July, 1942, Grunion encountered the Japanese freighter Kana Maru off Kiska Island. Grunion fired two torpedoes. One hit but the other torpedo missed. The single torpedo stopped the main engines and flooded the machinery room, leaving dead in the water with no power and no radio communications.Using this new information, two sons of Grunion's Captain mounted a search for their father's submarine in August 2006. Sufficient sonar images were located that a second search was mounted this year, and just a few days ago, the group announced that Grunion had been located and photographed.
Grunion fired a third torpedo which passed directly under the stricken Kana Maru, but did not explode. She then fired three more torpedoes. Two actually hit the ship but failed to explode.
After the third salvo of torpedoes, Grunion apparently decided to attack the merchant ship with her 3" 50-caliber deck gun (the same kind of gun at the museum). As she came to the surface, Grunion was struck by a round from an 80mm gun (about 3.25") installed by the Japanese Navy aboard Kana Maru. The round hit amidships, in the area of the bridge/conning tower/control room. It is likely that Grunion's Captain, most of her senior officers, and her most experienced men would have been killed instantly, as they would have been on duty in this area.
The men aboard Kana Maru saw a swell of heavy oil after this hit, and a great deal of oil and debris were found in the area.