America's Real WWII Flying Fortress Was The Massive Douglas XB-19Tyler Rogoway9/11/14 12:32pmFiled to: bombersWWIIhistory10056EditPromoteShare to KinjaToggle Conversation toolsGo to permalinkDuring the mid 1930s, the Army Air Corps wanted to push the technological envelope when it came to building a very long range bomber. Code named 'Project D,' this top-secret initiative would lead to the largest American bomber concept flown during World War II, the massive yet elegant Douglas XB-19. Under Project D, two major manufacturers, Douglas and Sikorsky, were competing at a chance to build what would be the most advanced bomber ever conceived by the US. Much like modern classified bomber competitions, both manufacturers were given a designation, those being the XBLR-2 for Douglas, and XBLR-3 for Sikorsky, with BLR standing for 'bomber, long-range.' The Army ordered full-scale mock-ups of each design for evaluation.