Dulacki served aboard the Hornet during the Doolittle Raid on Tokyo in April 1942 and was promoted to the rank of first lieutenant in September of that year. He was aboard when the carrier participated in the Battle of Midway in June 1942, and later when it was sunk during the Battle of the Santa Cruz Islands on October 26, 1942. He was rescued by escorting destroyers and sent to Pearl Harbor, Hawaii where he was promoted to the rank of captain in March 1943. Dulacki assumed command of the Marine detachment aboard the newly commissioned light aircraft carrier USS "Belleau Wood" and took part in the Gilbert and Marshall Islands and Mariana and Palau Islands campaigns during 1944. He was promoted to the rank of major in January 1944. Dulacki subsequently took part in the Battle of the Philippine Sea, during which Belleau Wood was severely damaged by a kamikaze in October 1944.