Even though they did not follow through, the XB-70 Valkyrie was a beautiful bird.
I had to fortune or in some cases misfortune to be stationed at Edwards Air Force Base for during one of the greatest periods of aviation advancement in history. While I was there the X-15, XB-70, XV-42, YF-12 and many other new platforms were flying. Was there when the XB-70 crashed. During that era envelops were being pushed and everything seemed to crash at least once. In the case of the XB-70 it when down after a mid air with a F-104 during a publicity filming flight.
Sad day. Lost good hardware but most of all good men.