She was converted to an aircraft transport by Tietjin & Land Dry Dock Corporation, Hoboken, New Jersey and commissioned on 26 November 1941, at New York Navy Yard.

After shakedown, Kitty Hawk departed New York on 16 December 1941, for Hawaii via the Panama Canal with aircraft to replace U.S. losses in the Japanese attack, and arrived at Pearl Harbor on 8 February 1942.

En route, a PBY Catalina reported a submarine in the area which Gwin drove off with a heavy barrage of depth charges, enabling Kitty Hawk to deliver her vital fighting men and aircraft to Midway on 26 May.

Kitty Hawk returned to Pearl Harbor on 31 July; loaded men, equipment and aircraft of the 2nd Echelon of the 23rd Marine Air Group; and set course for Port Vila, Efate, New Hebrides, arriving on 28 August.

From 20 February 1943 – 25 June 1944, Kitty Hawk made seven voyages to Hawaii and seven to the Southwest Pacific carrying vital aircraft, fighting men and munitions to be used in pressing forward toward Japan.

Kitty Hawk arrived Bayonne, New Jersey on 15 December; visited Norfolk, Virginia: decommissioned at New York on 24 January 1946; and was returned to her owner, Seatrain Lines, Inc., the same day.

[1] Reverted to her old name SS Seatrain New York in Chester, PA, she remained a cargo ship until being sold to Hua Eng Copper and Iron Industrial Company Limited of Taiwan for scrapping in March 1973.