The pre-production version of the Boeing B-29 Superfortress – the XB-29 bomber – in flight.
This XB-29-BO (serial number 41-18335) the third built bomber, he received the name “Gremlin Hotel”. The new aircraft received improved engines of the Wright Cyclone and was modified. But the engine problems with the serial B-29s continued until the end of the war. Later this aircraft was used to develop the B-29 assembly line and crashed during subsequent flight tests.