[hn_throwaway_99]

I'm not involved in aerospace. What is "the engine question"?

[baybal2]

There is simply no civilian engine out there for an SST. Even original Concorde engines are not what they need today.

Even the best military engines today will barely work for the role.

They need around 20t of dry thrust at speeds at speeds around Mach 1.7-2.0, and big enough fan for takeoff at the same time.