The propeller itself was of sheet iron, 5 feet 9 inches in diameter and about 5 feet long, and consisted of a full 360° screw, single threaded and of a single turn in keeping with Smith's revised 1836 patent. Following the ship's entry into service, the propeller would subsequently undergo a number of modifications, the most important of which were an alteration to a double threaded/half turn format, and a division of the original 360° screw into two separate blades. The propeller had the unusual feature of being fully retractable in order to reduce drag when the ship was under sail—a task that took about 15 minutes.[16]