Meanwhile, in August 1915, the General Board of the United States Navy approved the purchase of a single experimental small torpedo boat that could be transportable. This contract for C-250 ended up going to Greenport Basin and Construction Company, of Greenport, NY. When it eventually was delivered and tested in the summer of 1917, it was not deemed a success, so a second boat (C-378) of the sea sled design was ordered from Hickman in either late 1917 or early 1918 (conflicting dates). Using his previous design from September 1914 and the previous unsuccessful bid for C-250, the new boat C-378 was completed and fully tested just in time to be cancelled by the Armistice. With a full loaded weight of 56,000 pounds, C-378 made a top speed of with , and maintained an average speed of in a winter northeaster storm with seas, which would still be considered exceptional even 100 years later. The Sea Sled would not surface again as a torpedo boat topic until 1939, but would continue to be used by both the Army and Navy as rescue boats and seaplane tenders during the 20s and 30s. In 1922, the US Navy reconsidered using small internal combustion engine powered torpedo boats. As a result, two types and of British Royal Navy Coastal Motor Boats were obtained for testing. The larger boat was used for experiments until 1930. In 1938, the U.S. Navy renewed their investigation into the concept by requesting competitive bids for several different types of motor torpedo boats, but excluded Hickman's Sea Sled. This competition led to eight prototype boats built to compete in two different classes. The first class was for boats, and the second class was for boats. The resulting PT boat designs were the product of a small cadre of respected naval architects and the Navy.