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USS Grampus (SS-207)

USS Grampus (SS-207) patch

The USS Grampus (SS-207) was a Gar-class World War II era submarine. The Gar-class boats were duplicates of the Tambor-class design. 1

The namesake of the USS Grampus is a large cetacean (Grampus griseus) of the "blackfish family" commonly referred to as Risso's dolphin. Found in warm seas throughout the world, the dolphin has a blunt head, barrel-shaped body and ranges in color from grey to black. Risso's dolphins swim in groups and prefer offshore waters, where they hunt squid, octopi, and fish.

On February 11, 1943, the Grampus departed Brisbane for her sixth and final war patrol captained by Lieutenant Commander John R. Craig. Her orders were to patrol in the Solomon Islands area. She was never heard from again after leaving her exercise target on February 12, 1943. She failed to respond to radio messages sent to her by ComTaskForce 72 on March 7 and 8, 1943, and was reported lost on March 22, 1943. The public announcement was made about three months later: 2

Navy Department Communiqué No. 408, June 12, 1943

1. The U. S. submarines Amberjack and Grampus have failed to return from patrol operations and must be presumed to be lost.

2. The next of kin of personnel in the Amberjack and Grampus have been so informed.

The Grampus was struck from the Naval Vessel Register on June 21, 1943.

On February 18, 1943, the Grampus damaged the Japanese transport and aircraft ferry Keiyo Maru off New Britain. The submarine closed the damaged ship and torpedoed her again the following day at 04° 55' S, 152° 26' E. The attacks by the Grampus provoked an aggressive enemy response and the next day Japanese naval aircraft of the 958th Air Group reported bombing and sinking a submarine southeast of New Britain at 05° 40' S, 152° 18' E. They reported one direct hit on the conning tower and a large amount of oil on the surface after the attack. It is possible that this submarine was the Grampus3

On March 2, 1943, the Grampus was ordered by radio to leave her patrol area off northern Buka Island and to patrol further south with the USS Grayback (SS-208) in the Vella Gulf. Their objective was to intercept and sink any Japanese ships trying to pass westward through the Blackett Strait to escape from a U. S. naval bombardment of Vila and Stanmore airdrome on March 6th. There is no proof the Grampus ever received these orders, because she was not heard from after February 12th. However, a submarine commander in a hot war zone such as the Solomons often maintained strict radio silence unless he had a critically important message to send. Once on station in the gulf, the Grayback had one sonar and visual contact, which she believed to be the Grampus. The Grayback turned to avoid her. If the contact was the Grampus, it was the last contact friendly forces ever had with her. On the night of March 5, 1943, the IJN destroyers Murasame and Minegumo delivered supplies to the Japanese garrison at Vila on Kolombangara. As they withdrew after landing their cargo, they encountered Rear Admiral Aaron S. Merrill's task force of cruisers and destroyers in the Kula Gulf and were sunk. On March 6, 1943, a large oil slick was reported in Blackett Strait. This report together with the contact made by the Grayback fueled conjecture that the Grampus may have encountered and been sunk by the two Japanese destroyers before their battle with Merrill's task force. There is no evidence to support this conjecture. Fifty-three survivors from the Murasame and 122 survivors from the Minegumo managed to return to Japanese lines. Two other survivors from Minegumo were captured by American forces. No reports were received from the destroyers or their survivors about antisubmarine activity. How and when the Grampus was lost remains a mystery. 4

New Georgia Group Closeup

A list of the personnel lost with Grampus is maintained at On Eternal Patrol.

Grampus received three battle stars for her World War II service. Her first, fourth, and fifth war patrols were designated successful. JANAC scored the Grampus with sinking one ship, the 8,636-ton tanker Kaijo Maru No. 2 on March 1, 1942. Her Alden-McDonald score is one vessel sunk for 8,636 tons and two vessels damaged for 11,611 tons. The SORG score for the Grampus is six vessels sunk for 45,400 tons and three vessels damaged for 9,400 tons. 5

Patrol Data & Tonnage Scores


1. Alden, John D., The Fleet Submarine in the U. S. Navy: A Design and Construction History, p. 74.

2. United States Submarine Losses World War II, p. 37.

3. Dictionary of American Naval Fighting Ships, USS Grampus (SS-207); Miller, Vernon J., "U. S. Submarine Losses," issue 43, p. 205; Hackett, Bob, Sander Kingsepp and Peter Cundall, "IJN KEIYO MARU: Tabular Record of Movement," published online at Combined Fleet.

4. Holmes, Wilfred J., Undersea Victory: The Influence of Submarine Operations on the War in the Pacific, p. 213; Miller, Vernon J., "U. S. Submarine Losses," issue 43, p. 205; Nevitt, Allyn D., "IJN Minegumo: Tabular Record of Movement," published online at Combined Fleet; Nevitt, Allyn D., "IJN Murasame: Tabular Record of Movement," published online at Combined Fleet; Map of the New Georgia group in the Solomon Islands used in accordance with the GNU Free Documentation License.

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 Grampus (SS-207), Attack Nos. 81, 92, 371, 415, 422, 474, 475, 528, 529, 621, and 640; Submarine war patrol reports on CD, 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 Grampus (SS-207).