what is ss mauna loa?
A steam-powered cargo ship
SS Mauna Loa
SS "Mauna Loa was a steam-powered cargo ship of Matson Navigation Company that was sunk in the bombing of Darwin in February 1942. 
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SS Mauna Loa [SEP] Introduction
SS "Mauna Loa was a steam-powered cargo ship of Matson Navigation Company that was sunk in the bombing of Darwin in February 1942. She was christened SS "West Conob in 1919 and renamed SS "Golden Eagle" in 1928. At the time of her completion in 1919, the ship was inspected by the United States Navy for possible use as USS "West Conob" (ID-4033) but was neither taken into the Navy nor ever commissioned. "West Conob" was built in 1919 for the United States Shipping Board (USSB), part of the "West" series of ships—steel-hulled cargo ships built on the West Coast of the United States for the World War I war effort—and was the 14th ship built at Los Angeles Shipbuilding & Dry Dock Company in San Pedro, California.