Are there any hypersonic (Mach 5+) planes in service or officially being built? Or all the talk I here about the SR-72 rumor. Thanks!
As far as supersonic commercial flight goes, Nope. The Concorde and the Tupolev Tu-144 are both long retired.
As pointed out in the comments, hypersonic commercial flight has never existed.
The SR-72 you speak of is supposed to be flying by 2025.
This article points out that
Only a few experimental planes have ever reached hypersonic speed, and the last time a hypersonic plane flew with a person on board was in 1967. That plane, the North American X-15, was powered by rocket engines, which are impractical for commercial air travel.
The same article mentions a potential 'in-development' aircraft:
The Stratofly consortium plans to begin wind tunnel tests of the engine components. But it will take many years to bring Stratofly to life. The key technologies might not be ready until 2035, Viola says, with another decade needed before flight tests are completed and the plane is ready to carry passengers.
Right now none are routinely flying and only two aircraft, the experimental X-43 and the X-15 ever made powered hypersonic flights successfully.
Hermeus Corporation has a Mach 5 ramjet-powered business jet under development. Lockheed Martin has been developing a Mach 6 aircraft under the designation SR-72 and has stated the real aircraft could be flyable by 2025. And the X-30 National Aerospace plane made simulated flight of fancy some thirty years ago.
Hypersonic weapons have made great strides in the form of surface to surface and surface to air missiles as well as EM propelled projectiles ie ‘railguns’ capable of firing projectiles at speeds ranging from Mach 7 to Mach 13 and offering greater kinetic smash at the target than a chemically propelled round with a conventional explosive warhead.
All of these aircraft still remain fantastic ideas and cool airbrush art or CGI concepts. Out of all the concepts outs there, I’d venture a guess that the LMACO SkunkWorks concept aircraft has the greatest chance. There still remains a colossal amount of engineering needed to get craft like this flying successfully. I’d suggest reading Ben Rich’s book about the Skunk Works and the struggles they went through in the 60s to perfect the A-12/SR-71 Blackbird, which was fairly tame compared to the thermal heating problems and novel propulsion system designs like SABER or SCRAMJETs.