At the end of the 1930–1931 academic year, Ainsworth returned to sea in the battleship to serve as that ship's navigator. Next came a tour in heavy cruiser and one as communication officer for the 14th Naval District before he reported to the Naval War College at Newport, Rhode Island, for the senior course. In June 1936, Ainsworth became the executive officer of the battleship and, two years later, he became Professor of Naval Science and Tactics at Tulane University in New Orleans, Louisiana.