SS President Coolidge Newport News, Virginia built the two ships, completing "President Hoover" in 1930. The keel for "President Coolidge" was laid 22 April 1930 and the ship was delivered 1 October 1931. They were the largest merchant ships built in the United States up to that time. Each ship had turbo-electric transmission, with a pair of steam turbo generators generating current that powered propulsion motors on the propeller shafts. Westinghouse built the turbo generators and propulsion motors for "President Coolidge" but General Electric built the turbo generators and propulsion motors for "President Hoover". In the "President Coolidge" twelve Babcock & Wilcox superheater
Calvin Coolidge his earliest American ancestor, John Coolidge, emigrated from Cottenham, Cambridgeshire, England, around 1630 and settled in Watertown, Massachusetts. Another ancestor, Edmund Rice, arrived at Watertown in 1638. Coolidge's great-great-grandfather, also named John Coolidge, was an American military officer in the Revolutionary War and one of the first selectmen of the town of Plymouth. His grandfather Calvin Galusha Coolidge served in the Vermont House of Representatives. Coolidge was also a descendant of Samuel Appleton, who settled in Ipswich and led the Massachusetts Bay Colony during King Philip's War. Coolidge attended Black River Academy and then St. Johnsbury Academy, before enrolling at