Was the SR-71 the only aircraft that produced that double sonic boom? I seem to remember that most of the ones that I heard were that type (in the late 60's). I think that there were a lot of the B-58's flying at that time, and that's what I thought they were.
Nope.Sonic booms were a lot more common when I was a kid, and I heard them out in the desert a few times (including a B-70 overflight).
In more recent years, the Shuttle coming into Edwards would give you a righteous double boom as it crossed the coast north of us.
Dunno the physics of it.
B-58 was before my time; don’t know about a double sonic boom, but the Hustler was very fast, and burned a lot of fuel. Some of the tanker guys I served with during my enlisted days told me it took an ungodly number of in-flight refuelings to get a B-58 from the CONUS to its planned target in the Soviet Union. That was a major reason the B-58 only had a 10-year operational career.