Mantiss: just to be clear, it is impossible that they used one of the original XB-70's.
Reason: Airframe 2 crashed in a photoshoot, airframe 1 has been retired from Nasa to a museum and airframe 3 never was finished. So the closest to an original Valkyrie would be finishing airframe 3. If they'd build a new airframe, they might as well incorporate some newer technology. So the age of the technology would be less relevant, and as it would be a new airframe the age of the aircraft would be no issue.
But it remains one huge aircraft to hide.
Well, there's a lot of wild stories out there (secret continued development of YF-23 in some sort of small bomber). AW&ST clearly says they do not have the rigid sources they require for a "real" storyon Black Star. In fact, there are very little to no sources that can be investigated as it seems, it all seems to boil down to stories.
Wait and see...
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