This was the first of two XB-42 "Mixmaster" a/c built. It first flew on 6 May 1944. The design showed great promise, but the end of WW2 saw the USAAF looking for jet powered designs and XB-42 didn't go into production. In 1946 it was modified with a Westinghouse 19XB-2A podded turbojet under each wing, hence the "A" designation. It was donated to the Smithsonian Museum in 1949, never displayed, and transferred to the USAF Museum in 2010. It is located in the restoration hangar and not on display.