The USAF pursued two different systems for nuclear-powered jet engines, the Direct Air Cycle concept, which was developed by General Electric, and Indirect Air Cycle, which was assigned to Pratt & Whitney.
USAF ini mengejar dua sistem yang berbeda untuk mesin bertenaga nuklir jet, konsep Direct Air Cycle yang dikembangkan oleh General Electric, dan Indirect Air Cycle yang ditugaskan untuk Pratt & Whitney.