USS Oglala (CM-4) - Salvage, 1942

Salvage, 1942

Though Oglala was originally evaluated as a total loss, with the only salvage goal being to clear valuable pier space, it was ultimately decided to fully recover and repair the ship. The salvage effort was complex work, with the inherent difficulties of righting and refloating a capsized ship compounded by Oglala's poor stability. Fifteen to eighteen divers were kept busy for nearly 2000 underwater hours during the salvage, patching her hull, rigging chains, cutting away unwanted structure and executing many other tasks. After her tophamper had been removed, ten salvage pontoons were used to pull the ship upright while air was pumped into her to lighten the load. The first righting attempt, made on 11 April 1942, failed when several connecting chains parted. However, a second try succeeded twelve days later.

Oglala was now upright, but still mostly underwater. A large wooden cofferdam was built around the edges of her decks to allow water to be removed from her interior. The ship was refloated in June, but resank on 25-26 June when the failure of a pump led to cascading flooding in her forward hull. Afloat again on 29 June, she promptly went down for a third time when the cofferdam failed. After another raising, a serious fire on 2 July nearly produced a fourth resubmergence. However, the next day Oglala was finally drydocked, completing a job that became a legend among marine salvors. She received temporary repairs during much of the rest of 1942 and, in December, left Pearl Harbor for the U.S. west coast, there to be refurbished for active service.