[Note: hi everyone, this is my first post, my name is U235 or more conversly Dion. Im 16] Why is it everytime i look over schematics for the next nuclear rocket engine the design's are completley blindsided to nuclear physics and the harnessing of direct fusion and fission reactions. They all seem to depict a stupid design for increasing terminal velocity of hydrogen fuel and expanding it in the combusion chamber for propulsion purposes via a nuclear reactor. Surley this type of design should be outlawed to the fact that massive thermal constraints weigh on the design, and the engine must be always on in most design cases making it expendable. But the most infuriating -wrong- design facet is the lack to use direct fission + fusion for propulsion possibilities.