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USS Swordfish (SS-193)

USS Swordfish (SS-193) patch

The USS Swordfish (SS-193) was a Sargo-class World War II era submarine.

The namesake of the USS Swordfish is a large fish with a long, sword-like beak and a high dorsal fin.

The radio call sign of the USS Swordfish was NAN-UNCLE-DOG-GEORGE.

On December 22, 1944, the Swordfish, captained by Commander Keats E. Montross, departed Pearl Harbor for her thirteenth and final war patrol. She had received orders to patrol in an area off the Ryukyu Islands. She had also been outfitted with special equipment for a photo reconnaissance mission at Okinawa. After stopping at Midway Island to top off her fuel, she headed west for the big Japanese stronghold in the Nansei Shoto chain. On January 3, 1945, she acknowledged receipt of new orders to proceed to and to patrol near the approximate geographic position 30° 00' N, 132° 00' E until further notice. The reason for this move was to keep her out of harms way during a planned January carrier strike on the Ryukyus. Her acknowledgement of this order was the last communication ever received from the Swordfish. On January 9, 1945, she was ordered to proceed to the Nansei Shoto Archipelago to perform her special mission. Upon completion of the photographic and observation mission, she was told to proceed to the submarine base at Saipan, unless she was unable to communicate by radio, in which case she was supposed to return to Midway. When the Swordfish failed to appear at Saipan or Midway, and silence was the only response to radio messages sent to her, it became obvious she was lost. 1

On February 15, 1945, she was reported as presumed lost due to unknown causes. The public announcement was made on May 4, 1945.

Navy Department Communiqué No. 595, May 4, 1945

1. The submarine USS Swordfish is overdue from patrol and presumed lost. Next of kin of officers and crew have been informed.

Loss Possibilities

1. The Swordfish was probably sunk by depth charges, on January 5, 1945, at the approximate geographic position 29° 25' N, 141° 07' E, which is southeast of Tori-shima island, an uninhabited volcanic island at the south end of the Izu Islands. On that date, near that location, at about 1705 hours, the 572-ton Japanese Army cargo vessel Shoto Maru was hit in the bow by a torpedo and sank at about 1906 hours. John D. Alden attributes this attack and the sinking to the Swordfish. The Japanese coastal defense vessel CD-4 conducted a counterattack with depth charges and reported that oil continued to rise to the surface for the next thirty hours. 2

2. The Swordfish possibly sank sometime after January 9, 1945, as a result of hitting a mine. During the first half of 1944, the Japanese had laid four minefields in the Okinawa area. On January 9, 1945, the Swordfish had been ordered to proceed to this area to complete a photographic reconnaissance assignment. This mission may have taken her into one of the minefields laid in 1944 or into freshly laid inshore minefields planted to defend Okinawan beach approaches. 3

3. On January 12, 1945, the USS Kete (SS-369), while on station in the Okinawa area, reported a possible contact with a nearby submersible. The Kete was unable to positively identify the contact, but the Swordfish was expected to be in the vicinity at that time. About four hours later, the Kete heard the sound of a heavy barrage of depth charges. Japanese records reviewed after the war did not record the event heard by the Kete. But such a heavy barrage could have been aimed at the Swordfish4

The bottom line is no one knows for certain what happened to the Swordfish. This long serving submarine and her valiant crew went down together leaving a significant record of accomplishments in their wake.

A list of the men lost with the Swordfish is maintained at On Eternal Patrol.

The Swordfish was scored by JANAC with sinking 47,928 tons of enemy shipping in twelve vessels. Her Alden-McDonald score is sixteen vessels sunk for 55,641 tons and four vessels damaged for 26,150 tons. Her SORG score is seventeen vessels sunk for 101,400 tons and nine vessels damaged for 61,900 tons. The Swordfish earned eight battle stars for her World War II service in her distinguished thirteen-patrol career. She sank the Atsutasan Maru, the first Japanese ship sunk by a U. S. submarine in the Pacific war. 5

Patrol Data & Tonnage Scores

USS Swordfish (SS-193) Second Patrol


1. United States Submarine Losses World War II, p. 132.

2. Miller, Vernon J., "U. S. Submarine Losses," issue 44, p. 57; Hackett, Bob, and Sander Kingsepp and Peter Cundall, "IJN Escort CD-4: Tabular Record of Movement," published online at Combined Fleet; Alden, John D., and Craig R. McDonald, United States and Allied Submarine Successes in the Pacific and Far East During World War II, Fourth Edition, Attack No. 3359.

3. Miller, Vernon J., op cit.; Holmes, Wilfred J., Undersea Victory: The Influence of Submarine Operations on the War in the Pacific, p. 436-437.

4. Ibid.

5. Alden, John D., and Craig R. McDonald, United States and Allied Submarine Successes in the Pacific and Far East During World War II, Fourth Edition, see USS Swordfish (SS-193), Attack Nos. 1, 14, 15, 16, 17, 47, 48, 63, 67, 177, 186, 187, 198, 199, 434, 443, 557, 1044, 1045, 1084, 1496, 1496.5, 1506, 1558, 1806, 1807, 2073, 2099, 2100, 2143, 2145, 2179, 2220, and 3359; Submarine war patrol reports on CD, USS Swordfish (SS-193), data collected by the Submarine Operations Research Group (SORG) in the report "Results of U. S. Submarine War Patrols Listed Alphabetically by Name of Submarine"; Japanese Naval And Merchant Shipping Losses During World War II By All Causes, Joint Army-Navy Assessment Committee, USS Swordfish (SS-193).