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The SR71 was flying at a much higher altitude to achieve lower drag and fits 2 pilots, 0 commercial passengers.

If you want to compare apples to apples, I suggest you refer to the 2 metrics I mentioned: - gallons of fuel per miles flown - fuel used per passenger

One without the other is a useless comparison as you pointed out.

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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? :)

Maybe you just wanted to understand the point in a certain way so you could argue about it?

Certainly fair. I can't see any world where the comparison is relevant, though. :(

Down thread it was pointed out that sports cars are more efficient than busses. Per vehicle. This is about the same idea, at best.

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