Long a source of speculation throughout the defense commentary sphere, the SR-72 “Son of Blackbird” next-generation drone has been mired in mystery for over a decade.
The SR-72 is the planned successor to the SR-71, the iconic Cold War-era reconnaissance plane that shattered world records for the fastest manned airbreathing jet engine aircraft. Initial reports emerged as early as 2007, but it was only in 2013 that Lockheed Martin official Robert Weiss publicly confirmed that the company had made significant headway into developing a hypersonic plane that he called the “SR-72.” Lockheed Martin proceeded to release widely shared concept art for the project—the SR-72 appears to be an unmanned aerial vehicle (UAV), boasting a groundbreaking purported top speed approaching Mach 6.
In yet another difference with its manned SR-71 predecessor, the SR-72 is a reconnaissance and surveillance craft that doubles as a strike weapon. The UAV will reportedly support hypersonic armaments such as Lockheed Martin’s High Speed Strike Weapon (HSSW), making the SR-72 a potent tool for delivering precision strikes against agile or otherwise hard-to-reach targets.
Following a four-year information drought, Lockheed Martin dropped the announcement that the SR-72 will enter development by the early 2020s. Lockheed rationalized this prolonged interlude on the grounds that the technologies required to produce a plane that fast were not yet sufficiently mature: “Without the digital transformation the aircraft you see there could not have been made. In fact, five years ago, it could not have been made,” said Lockheed Vice President Jack O’Banion, referencing an artist’s SR-72 rendering presented at the American Institute of Aeronautics and Astronautics’ annual SciTech Forum in 2018. O’Banion’s statement seemed to imply that an SR-72 prototype or concept demonstrator already exists, prompting fevered interest from defense observers. Lockheed refused to clarify his comments, adding to what increasingly seems to be the company’s purposely cultivated aura of mystery surrounding the SR-72.
“We couldn’t have made the engine itself—it would have melted down into slag if we had tried to produce it five years ago,” O’Banion added. “But now we can digitally print that engine with an incredibly sophisticated cooling system integral into the material of the engine itself, and have that engine survive for multiple firings for routine operation.”
Lockheed Martin maintains that an SR-72 concept demonstrator will take to the skies by the mid-2020s, possibly entering service as soon as 2030. However, unanswered questions—and serious design challenges—linger. For one, it remains unclear exactly how the SR-72 is piloted; will it be operated in real-time by remote pilots, or will it boast a sufficiently robust artificial intelligence (AI) suite to run missions with either no or minimal manual control? Further still, scramjet engine development is notoriously costly and complex. It will likely take many years and colossal investment for a possible SR-72 prototype to be realized as a serially-produced model.
It remains to be seen whether or not Lockheed manages to secure the considerable funding required to mass-produce a product as complex and cutting-edge as the SR-72, especially when it’s unclear what specific, pressing operational purpose it is supposed to fill. From sophisticated satellite surveillance methods to the next-generation B-21 bomber and Northrop Grumman’s new RQ-180 stealth drone, the U.S. military seems to have somewhat covered many of the individual capabilities being offered by the SR-72.
Mark Episkopos is a national security reporter for the National Interest.