Even though the Île de France was not the fastest vessel in the world, it briefly pioneered the quickest mail-system between the United States and Europe. In July 1928, a seaplane catapult was installed at the ship's stern for trials with two CAMS 37 flying boats that launched when the ship was within 200 miles, which decreased the mail delivery time by one day. This practice proved too costly, however, and in October 1930 the catapult was removed and the service discontinued. (Wiki)