Northrop YB-49 Flying Wing model. The YB-49 was born when Northrop modified two YB-35's to jet power, the first one flying on October 21, 1947. Many complimentary reports on the YB-49 were filed by Air Force officers, and the service was convinced of the advantages of the all-wing configuration, but in June 1948 the second YB-49 was destroyed with the loss of its five man crew in a crash attributed to structural failure. In spite of this, the Air force ordered 30 of the aircraft, but the order was later canceled in favor of the B-36. In October 1949 the whole program was canceled, and the aircraft were scrapped. Interestingly, the YB-49 was considered superior to the B-36 in almost every way.