I can imagine that those who have seen the wrong side of "Ballistic", getting up there is the easy part, it's where you're at when you return to being non-ballistic that matters. Trajectory, free fall dynamics, vehicle stress and human factors when the driver is virtually SLF is the tricky bit.
Control was managed without main engine thrust in the shuttle so not insurmountable, and I am sure something similar is being done in the X37B but in a "fighting" Mig
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