The Mach 3+ D-21 drone concept (15 HQ Photos)

Looks like a scaled down SR-71 engine with wings…interesting.

Now that my friends is some expensive paranoia.

They've got one at the USAF Museum at Wright Patt… And to think how long ago those were made… and what could exist now.

Tellin ya, if the SR-71 had never been and was rolled out for the first time today, you'd call BS and think it was stolen alien technology. That design was genius and beautiful to boot.

And all designed with slide rules…. awesome.