46 U.S. Code § 11202. Qualified service

For purposes of this chapter, a person shall be considered to have engaged in qualified service if, between August 16, 1945, and December 31, 1946, the person—
(1) was a member of the United States merchant marine (including the Army Transport Service and the Naval Transport Service) serving as a crewmember of a vessel that was—
operated by the War Shipping Administration or the Office of Defense Transportation (or an agent of the Administration or Office);
operated in waters other than inland waters, the Great Lakes, and other lakes, bays, and harbors of the United States;
under contract or charter to, or property of, the Government of the United States; and
serving the Armed Forces; and
while so serving, was licensed or otherwise documented for service as a crewmember of such a vessel by an officer or employee of the United States authorized to license or document the person for such service.