The OKB -1 EF 140 a prototype aircraft was developed in the Soviet Union by German engineers who had been captured at the end of the Second World War. They belonged to the German company Junkers and the Nazis had built a jet prototype Junkers Ju 287 which served as a model. Significant changes were however made by the engineer Brunolf Baade . The aircraft was developed by the company Space Corporation Energia (OKB). It was originally designed as bomber. Then as reconnaissance aircraft.