Giant Flying Boat in Final Test -- The Navy's Huge Air Cargo Vessel, the flying boat "Mars," is accompanied by a Brewster Buccaneer on a routine flight as a final test before being turns over to the navy by the ***** L. Martin company, of Baltimore, builders. In the final test the "Mars" flew 34 hours, 17 minutes without stopping, equivalent to a trip from New York to Berlin. The huge flying boat will be used by the navy to haul critical supplies and personnel to distant war theaters. October 30, 1943. (Photo by Associated Press Photo).