Planned to ultimately be about the same size as the 33.6m long SR-71A Blackbird which was retired in 1998, and bearing more than a passing resemblance to the Blackbird through its sharply swept wing and fuselage chine which runs from the nose to the wing leading edge and twin tails, the program will initially focus on a smaller F-16-sized concept demonstrator.
Boeing plans to leverage its experience on hypersonic demonstrator programs such as the X-43 and the X-51A Waverider, both of which featured sharply-swept delta wings, and Boeing legacy company Rockwell’s experience going all the way back to the Mach 3 capable XB-70 bomber program of the 1960s.
“It’s a really hard problem to develop an aircraft that takes off and accelerates through Mach 1 all the way to Mach 5 and beyond,” Kevin Bowcutt, Boeing chief scientist for hypersonics told media at the concept unveiling in Florida on January 10.
“The specific impulse of an air breathing engine goes down with increasing velocity, so you have to make the engine bigger to get to Mach 5. But doing that means a bigger inlet and a bigger nozzle, and trying to get that through Mach 1 is harder.”
The Boeing design follows a similar looking concept being studied by Lockheed Martin’s famed Skunk Works advanced projects division, the notional ‘SR-72’.