I kind of think of the scott/bryant thing as the raw material, like what they gave Welles before he directed TOUCH OF EVIL. Kaufmann has a tendency to rewrite anyway (anybody who knows William Goldman's take on RIGHT STUFF will get that reference), and his stated intent to explore mythology, and his referring to Olaf Stapledon, both suggest that he was going to do something WITH trek (which may also mean TO it.) Lucas had the same idea when he inquired about buying ST and FLASH GORDON , I'm sure he wouldn't have kept much of the trek or Flashverse at all.
As for the influence, I hadn't heard of the jet, but that is the kind of thing that would appeal to Ken Adam. However I've never seen Adam reference that plane either. maybe when we get the new Adam book, it'll resolve itself (hope hope.)