The first American-built large bomber flown by the U.S. Navy and Marine Corps was the Glenn Martin GMB-1, as the Army designated the aircraft.1 The U.S. air services flew mostly European-built aircraft in combat during World War I. Thus, in January 1918 the U.S. Army awarded a contract to the newly established Martin aircraft company to design and build ten twin-engine reconnaissance bombers to replace the British Handley-Page and the Italian Caproni bombers then flown by the Army.
The chief designer of the GMB-1 was Donald Douglas, who would become one of the world’s leading aircraft designers of the World War II era. The Army’s first aircraft flew on 15 August 1918. Its success led the Navy to order ten of the bombers a year later, in September 1919. Two of the latter were duplicates of the GMB-1 for Navy service (designated MBT) and eight improved variants for the Marine Corps (MT).2