U miss the point entirely that supersonic planes work differently from “traditional” subsonic planes. Just assuming that “faster equals less fuel efficient” is not really correct. Turbofan engines are kind of draggy and not so fuel efficient close to Mach 1. Ramjets change your equation… :-)
The point is poorly made. Would be like talking about how fuel efficient the space station is for it's speed. Can only work if you ignore the trip to that steady state.
So, for the blackbird, how does it do on take off? You know, when it is literally leaking fuel? :)
