 Completing his tour as Battle Fleet commander on September 10, 1927, Jackson was relieved by Admiral Louis R. de Steiguer and reverted to his permanent rank of rear admiral and shore duty as a member of the General Board.In December, he was appointed to head the court of inquiry into the sinking of the submarine S-4.He remained on the General Board until he retired in 1930 upon reaching the statutory age of 64.