Boeing XB-38 Flying Fortress The XB-38 was destroyed and the project was canceled, in part because the V-1710 engines were needed for other projects such as the Lockheed P-38 Lightning, Bell P-39 Airacobra, Curtiss P-40 Warhawk, North American P-51A Mustang, and Bell P-63 Kingcobra fighters. Boeing XB-38 Flying Fortress The XB-38 Flying Fortress was a single example conversion of a production B-17E Flying Fortress, testing whether the Allison V-1710 V type engine could be substituted for the standard Wright R-1820 radial engine during early World War II. The XB-38 was the result of a modification project undertaken by Boeing and Vega (a subsidiary of
B-17 Flying Fortress units of the United States Army Air Forces Liberators Was primary operator of B-17 Flying Fortresses in overseas combat theaters during World War II. The B-17 may have first seen combat in American markings in the Philippines, but it would earn its enduring fame with the Eighth Air Force, based in England and fighting over Occupied Europe. The story of the B-17 would become the story of the VIII Bomber Command (later Eighth Air Force) strategic heavy bombardment campaign of the European Theater of Operations (ETO) during World War II Initially equipped with B-17Es in 1942, the Eighth Air Force received B-17Fs in Jan 1943 and B-17Gs in