USS Seahorse SS-304 (1943-1995)

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The first USS Seahorse (SS-304) was commissioned on March 31, 1943, and commanded by CDR Donald McGregor. The Seahorse encountered hostile vessels on several occasions during her war patrols off the Palau and Marianas Islands and the Luzon strait.

Action in World War II

The Seahorse embarked on her first patrol on August 3, 1943. Three weeks into her patrol, she engaged in hostiles and torpedoed two Japanese vessels before refitting on September 27 at Midway.  On her second war patrol, the Seahorse encountered and sank as many as eight Japanese vessels, including the cargo ships Chihaya Maru, Ume Maru, Daishu Maru, and San Roman Maru. War weary, she then returned to Pearl Harbor on December 12.

The Seahorse embarked on her third war patrol on January 6, 1944 and shortly after shipping off, sank the Nikko Maru cargo ship en route to the Palaus. Until setting off for refit on February 16, the Seahorse reported sinking at least three more Japanese ships: Yasukuni Maru, Ikoma Maru and Toei Maru.

The submarine’s fourth and fifth war patrols took place off of the Marianas where the Seahorse reported the sinking of even more enemy cargo ships: Aratama Maru, Medan Maru, Nitto Maru, Gyoyu Maru, Kyodo Maru No. 28, Kizugawa Maru, and Bisaku Maru. She also sank her first enemy submarine RO-45 during these patrols on April 20.  From mid-1944 to summer of 1945, Seahorse acted as a lifeguard station over her sixth and seventh war patrols. But again she managed to sink another ship, a frigate by the name of Coast Defense Vessel No. 21.

After the War

After an overhaul on March 9, 1945, Seahorse was decommissioned little over a month after her eighth and final war patrol, which ended at the close of the war on August 15. She then served as a part of the Pacific Reserve Fleet until being struck from the Naval Register on March 1, 1967. She was awarded nine battle stars for her service in World War II.

Asbestos in Navy Ships

Although an essential component of the naval fleet, especially throughout conflicts of the last century, submarines also pose a lasting health risk to soldiers serving on them. However, these risks extend beyond the inherent dangers that existed while operating the vessels during military conflicts. Unfortunately, products containing asbestos were also common aboard submarines because of the material’s high resistance to heat and fire. Despite its value as an insulator, asbestos fiber intake can lead to several serious health consequences, including mesothelioma, a devastating cancer without cure. Furthermore, the enclosed environment of submarines put servicemen at an even higher risk of exposure. Current and former military personnel who came into contact with or served on submarines should seek immediate medical attention in order to detect possible health consequences associated with asbestos exposure.


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