The Boeing B-17 Flying Fortress is a four-engine heavy bomber developed in the 1930s for the United States Army Air Corps (USAAC). Competing against Douglas and Martin for a contract to build 200 bombers, the Boeing entry outperformed both competitors and exceeded the air corps' performance specifications. Although Boeing lost the contract because the prototype crashed, the air corps was so impressed with Boeing's design that it ordered 13 more B-17s for further evaluation. From its introduction in 1938, the B-17 Flying Fortress evolved through numerous design advances,press 1 to active the turriets,2 is the landing lights.wish you have fun with this B17 and upvote her