Got to see one fly over in 1966 or 67. Was on deployment at Fallon NAS when we spotted one way up there screaming along. Never saw anything move that fast across the sky since then, and have seen fighters supersonic in the Mojave corridor. Not even close.
The white color and shape were beautiful. Nice boom too. Funny, but I don't recall any chase planes, probably none could keep up, however fast it was going.
IIRC, they had a B58 chase plane that could keep up until around Mach 2.5, but it would use up all its fuel right away. So therefore no chase plane could keep up with it.
I think the B-70 with a few enhancements would have been much more effective than they gave it credit for. A squadron coming in at M3.4, good ECM and SRAM’s could have overwhelmed their defense network.
The B70 in that incarnation did not have enough mission flexibility for its cost.