Dr. Kollmann (and his colleagues) were keenly aware that the jet engine was the powerplant of future. They clearly stated this when interrogated by the British intelligence agents in June 1945 (from Report POW/ENG/6, Evaluation Report No. 539, 16 Apr 46). They thought that the piston engine would still be used for some time to come for transport purposes, but they did not think that it had much application in war time. They anticipated that the jet engines would constitute the bulk of the fleet, to the tune of 60-70%. However, they did not foresee a full demise of piston engines.