First YB-49 was flown on October 21, 1947. The fuselage is with a long narrow nose and a triangular tail fin. Engines are housed in semi-circular pods on either side of the lower fuselage. Engines exhausts are located aft of the wings. Wings are uswept with permanent fuel tanks on tips.
Tailplane is swept along the leading edge.
Landing gear with nose wheel is retractable. First F-89 prototype flew on August 16, 1948. F-89H and J remained in service until 1958, the last airplanes serving with US Army Reserve and US National Guard. The fuselage is narrow with a tall tail fin and a pointed nose. Tailplane is also delta-shaped with tapered tips.