If the SR-71 was “replaced by satellites” (and I’m not disputing that), explain why the U-2s are still flying, and why is there a Global Hawk program, etc?
The continuing need for immediate, real-time intel collection. Satellites are pretty much strategic intel vehicles that take time to reposition, unless they’re by some good fortune, directly over the hotspot. The U-2 and various UAS’s are tactical vehicles that can redirected more quickly than satellites.
Expense of keeping the SR airborne.
The dang thing leaked until it hit cruising speed. All that heat also causes metal fatigue.
Years ago, they put one of the retired SR’s at the old Offut museum. It hadn’t been totally decommissioned yet. There was an old crewman talking about the work to keep the engines going.
I will never forget the feel of the skin of that bird. Like hard cardboard.