"Arthur Foss" successfully delivered the drydock gate to the navy yard at Pearl Harbor in early March 1941. Instead of returning to the West Coast, the vessel was chartered by Foss to a consortium of civilian engineering firms: Contractors Pacific Naval Air Bases (CPNAB), which had been formed in January 1941 to begin construction of military bases on strategic Pacific atolls, including Wake Island. "Arthur Foss"'s first assignment with CPNAB was towing gravel barges from Kaneohe to Honolulu for construction of airport runways. This work lasted until June, when the tug was assigned to a regular run between Hawaii and Wake towing barges of construction materials and military supplies for the airfield and barracks there. Meanwhile, the United States quietly prepared for the coming of war. In November, amid increasing U.S.-Japanese tensions, the tug was again dispatched from Honolulu under the command of Captain Oscar Rolstad to Wake towing two fully loaded barges. Upon arrival, "Arthur Foss" was joined by the smaller "Justine Foss" in the atoll harbor. Offloading the barges and lightering the equipment ashore occupied the two tug crews for the next few weeks. Upon completion of the work, "Arthur Foss" was scheduled to return to Honolulu towing two 1,000-ton fuel barges (empty). Departure from Wake was expected in the first week of December.