Grampus file photo [3630]


CountryUnited States
Ship ClassTambor-class Submarine
Hull NumberSS-207
BuilderElectric Boat Company
Launched23 Dec 1940
Commissioned23 May 1941
Sunk5 Mar 1943
Displacement1,476 tons standard; 2,370 tons submerged
Length307 feet
Beam27 feet
Draft13 feet
Speed20 knots
Armament1x3in gun, 10x torpedo tubes


ww2dbaseWith Lieutenant Commander Edward S. Hutchinson in command, submarine Grampus held her shakedown cruise in Long Island Sound off the east coast of United States. She patrolled in the Caribbean Sea with submarine Grayback between 8 and 28 Sep 1941. When the United States entered the war in Dec 1941, she was undergoing post-shakedown overhaul at Portsmouth, New Hampshire. She sailed for the Pacific Ocean in late 1941, arriving at Pearl Harbor on 1 Feb 1942. On her first war patrol from 8 Feb to 4 Apr 1942, she scored the only kill of her career, a Japanese 8,636-ton tanker. On 2 Oct 1942, she departed for her fourth war patrol with four coast watchers on board. She landed the coast watchers on Vella Lavella and Choiseul islands in the Solomon Islands. On this patrol, she attacked Japanese warships aggressively, including a torpedo hit on cruiser Yura that failed to explode, but did not score any kills; 104 depth charges were launched against her during this war patrol, but she escaped unscathed. Her fourth war patrol ended on 23 Nov 1942 in Australia. Her fifth war patrol between 14 Dec 1942 to 19 Jan 1943 was similarly aggressive, but again she did not score any kills. On 11 Feb 1943, Grampus set aside from Brisbane, Australia on her sixth war patrol from which she never returned. Her sinking is still a mystery today. It is presumed that she was sunk by Japanese destroyers Minegumo and Murasame in the Battle of Blackett Strait near Kolombangara Island because a heavy oil slick was sighted there the day after communications were lost with Grampus.

ww2dbaseSource: Wikipedia.

Last Major Revision: May 2007


Port quarter view looking forward showing submarines Gar and Grampus fitting out, Groton, Connecticut, United States, 3 Jan 1941Grampus during her trials, off Groton, Connecticut, United States, 26 Mar 1941, photo 1 of 2Grampus during her trials, off Groton, Connecticut, United States, 26 Mar 1941, photo 2 of 2Starboard quarter view looking forward showing USS Gar and USS Grampus fitting out, 30 Mar 1941

Grampus Operational Timeline

8 Feb 1941 USS Grampus began patrolling in the Caribbean Sea.
23 May 1941 Grampus was commissioned into service.
8 Sep 1941 USS Grampus began patrolling in the Caribbean Sea.
1 Feb 1942 USS Grampus arrived at Pearl Harbor, Oahu, US Territory of Hawaii.
8 Feb 1942 USS Grampus departed Pearl Harbor, Oahu, US Territory of Hawaii for her first war patrol.
4 Mar 1942 USS Grampus sank Japanese tanker Kaijo Maru in the Pacific Ocean, killing all 90 aboard.
4 Apr 1942 USS Grampus completed her first war patrol.
2 Oct 1942 USS Grampus began her fourth war patrol.
23 Nov 1942 USS Grampus arrived at Australia, ending her fourth war patrol.
14 Dec 1942 USS Grampus began her fifth war patrol.
19 Jan 1943 USS Grampus completed her fifth war patrol.
11 Feb 1943 USS Grampus departed Brisbane, Australia for her sixth war patrol.

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1. Anonymous says:
1 Mar 2018 04:19:14 PM

My Dad Robert Maynard 37102593 served with 63rd Inf Div 3rd Battalion 255th Inf. Reg. Action 3APR45 Rohrback Germany. Information difficult to find he was awarded Bronze Star. He passed keeping details to himself and little to no paper trail. Are you able to help?

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Event(s) Participated:
» Solomon Islands Campaign

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Submarine Grampus (SS-207) Photo Gallery
Port quarter view looking forward showing submarines Gar and Grampus fitting out, Groton, Connecticut, United States, 3 Jan 1941
See all 4 photographs of Submarine Grampus (SS-207)

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