BEagle,
At my old Part 145 MRO company, around 10 years back, the other other of the business was a Part 21G and J composite facility. We had a contract with a bunch of Bedfordshire academics and boffins to build the BWB scaled drop test models as said academics had been contracted by the Boeing Phantom Works. Also we got involved indirectly with the Cambridge Uni / MIT Silent Aircraft initiative
The 'Silent' Aircraft Initiative
Back to the BWB, below my feet in my Quality Dept, these shapes were built and then shipped off back to Huntington Beach and would find their way up to the Mojave and used for a series of crash test evaluations. I do not believe they were in anyway used as airborne tests from say NASA NB-52H or any other platform, but launched like as a UAS....
Last I heard the BWB scaled models we built, had all but one or two used and made a dent in the lovely Mojave desert,
Cheers