The Martin MB-2 was the first US designed bomber produced in large numbers and became the Air Service's primary multi-engine bomber until replaced by the Keystone bombers of the late 1920s. The Martin MB-2 designers incorporated an interesting element, since its large wingspan made it difficult to store in a hangar, the aircraft had hinged wings No original MB-2 exists rather the reproduction on display at the NMUSAF was built using original Martin drawings and completed in 2002.