Conclusions on Aircraft Reactor Program The overall direction of the program has decidedly improved. There is a real possibility of using nuclear propulsion effectively in operating weapons In view of the military potentialities as described to us, high urgency is warranted, General Electric's progress towards a workable propulsion system using © a’ the direct air cycle is distinctly encouraging. Even though the solutions to many problems are still outstanding, this program seems to warrant full and increasing support, | | The general concept of a sodium-cooled reactor should also be supported with high urgency. The Fluid Fuel approach presents some exceedingly difficult probleme and should be critically reviewed soon to determine whether it offers a reasorable chance of producing a workable power plant within the time schedule of weapmssystemsto which it is now committed. Recent strengthening of the ORNL staff is encouraging, but collaboration of Oak Ridge and Pratt & Whitney seems te be lagging. The active development of a heterogeneous reactor for the sodium cycle may well be justified and we suggest that the Reactor Division draft s proposed program, including type and scope of work and contractors, which san be presented at the next meeting of the General Advisory Committee. ee ee Ir, Wigner disagrees with the above statements on the Aircraft Reactor Program in the following respect (as expressed to Mr. Whitman): "The only point where I would like to differ with you is your very different appraisal of the two aircraft reactor programs. While I surely realize that the direct air cycle is a very promising avenue and is quite likely to be the one which ultimately survives, I also believe that the circulating fuel . . ae and pe oe * we ee ee Ontee lt w ee ” systems within ten years,