[benj111]

So what's changed since Concorde?

Concorde didn't fail for technical reasons but AA have put down a deposit for 60. This is limited to < Mach 1 over land so it's going to be most useful on the routes that Concorde could have serviced.

Is it just the noise aspect opening more potential routes? But then I would have thought we would be more concerned about noise now than in the 60s making the improvements a wash.