I think the A-12 just barely beats it for speed. The SR-71 had better range, could carry more sensors, and allowed a crew of 2. So in a lot of ways it was more capable, but not quite as fast. Though they are both so absurdly fast that I think it is pretty irrelevant.
Edit: But I do love that story. And I love that plane. Just bleeding edge engineering, and solving so many issues people weren’t even aware of when they started the design.
I didn’t actually realize how old the post was. No idea how I ended up on a 9 month old post 🤷🏻
I would love to see the A-12 in person. Even better if it was side by side with the SR-71.