No, it was a claimed SR-71 follow on called Aurora, with a “donuts on a rope contrail” said to be indicative of a pulsed or wave detonation engine. This is now mostly thought debunked.
SR-71 has the same diamond shaped pulses (or “donuts on a rope contrail”) in its exhaust.
Since most of this is TS-SAP, debunking any of it is problematic.