I know of the X15 plane achieving over 2km/sec speed at the edge of space. Launched from a B52 bomber and flown by pilots designated as astronauts, the year I was born. During the record Mach 6.93 flight, the aircraft received thermal structural damage and the covering was severely pitted and charred. Repair was uneconomical and the aircraft was grounded.
just to be pedantic;
I would only call it a manned hypersonic flight, when the plane takes off from ground with a turbofan/turbojet engine that transforms in to a scramjet engine at altitude and flies at 6mach, then reverts back to a turbofan/turbojet when at lower atmosphere.
I don’t think we are too far away for that to become a reality if you consider the advances being made in jet engine technologies in recent years.
Nearly 70 years on and we still have not actually gone over the threshold of technological advances to crack true manned hypersonic flight.
Then there is the hypersonic flight at lower atmosphere. For that the engine and vehicle construction and metallurgical science has to be at such a level that both the cost and durability of materials become acceptable.
Yah depends on definitions in the end. Obviously the X-15 has limited direct applicability to what we generally consider a "fighter plane" today.
But it was part of an ecosystem of thinking in early cold war about the "mothership" approach.... which would ultimately see greatest fruition in (what would later change course and become the XB-70...and then terminate due to various economies of scale involved w.r.t emerging missile + sensoring along with the XB-70 major accident that doomed it's evolution into anything else).
In that mothership approach, there was plenty of scope for potentially hypersonic manned fighter "modules/payloads" to take shape.
Who knows, one day it may see viable re-emergence....but they are unlikely to be manned as you have noted in earlier posts. There's just too much needed to be invested in keeping a pilot alive and functional compared to any benefit by having him compared to onboard AI only.
In fact with wingman drone concept etc the mothership concept is already taking new shape (at our current juncture of subsonic and supersonic etc)....so it will definitely be applied and scaled relevantly in the hypersonic realm as we unlock more of that with time.
How the "macro" evolves optimally in that remains to be see w.r.t is it more optimal to have a large mothership with drone payloads (that can go hypersonic)....
....or do you develop + have a complete system that is fully capable of all regimes. i.e a modern day blackbird with scramjet regime unlocked (by core bypass) this time instead of essentially ramjet back then.
Both may have their roles/places in an aerial doctrine.
