I just read Skunk Works by Ben Rich, senior employee on the SR-71 project and later director of that whole department, and he viewed a hypersonic airplane as an

I just read Skunk Works by Ben Rich, senior employee on the SR-71 project and later director of that whole department, and he viewed a hypersonic airplane as an eternal government boondoggle while leaving the door open that it might become possible one day. >you are proposing to fly at Mach 12, where the surface heat on the fuselage would be 2,500 degrees and still have a passenger cabin filled with women, children, and businessmen, sitting around in their shirtsleeves! Not in my lifetime. Nor in yours. Whoever dreamed up that presidential address ought to be canned. I’m not at all certain we would have that kind of technology ready by the middle of the damned twenty-first century, and if you don’t realize that, you are in the wrong business.” He relays the story of seeing Reagan propose a national hypersonic plane project in an address and angrily calling the White House’s chief science advisor to point out the Blackbird “only” flew at 3.2 because much faster than that the airplane’s surface would come apart from heat friction, so they’d need something stronger than titanium, and by the way the crew wore space suits and Lockheed still worried they’d boil alive if the A/C system failed. >But the lure of building a hypersonic airplane dies hard and has become fool’s gold to aerospace dreamers. The idea is still kicking around in Congress, its proponents in search of funding like a stray dog sniffing around for a bone. Building the airplane, to be called the X-30, will be a joint project of NASA and the Defense Department. But long before the first serious dollar is plonked down, someone in charge had better realize that Reagan’s “Orient Express” is really two separate concepts—one a rocketship and the other an airplane. Most likely, that particular twain shall never meet successfully. So it’s certainly amusing, decades after Rich published this book, to see the long history of his remarks looking true. On the other hand, we now approach the mid 21st century! At the end of the book, Rich writes optimistically about the future projects on the horizon at Lockheed and they include evaluating the feasibility of hypersonic airplanes to lift equipment to orbit. I wonder what will work better than the titanium body on the SR-71.