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 Bridge major improvement of the Coolidge Bridge, that cost a total of $32 million which included: In 2007 the Massachusetts Historical Commission determined that the Calvin Coolidge Bridge was not eligible for individual listing in the National Register of Historic Places but was eligible for listing as a contributing element in the (then) pending expansion of the Hadley Center Historic District. In 1994, the bridge was included as a contributing element to the Hadley Center Historic District. Calvin Coolidge Bridge The Calvin Coolidge Memorial Bridge is a major crossing of the Connecticut River in western Massachusetts, connecting the towns of Northampton