The SR-72 Son of Blackbird Has a Math Problem

The Lockheed Martin SR-72, often referred to as the “Son of Blackbird,” is a proposed hypersonic aircraft intended to fill a similar role as the retired SR-71 Blackbird. Designed for speeds in excess of Mach 6, or six times the speed of sound, the SR-72 could revolutionize reconnaissance and strike capabilities thanks to its incredible speed.

Like the Cold War-era SR-71, the SR-72 could penetrate contested enemy airspace to gather intelligence information and quickly scoot far away out of range.

The engineering challenge of such an aircraft would be significant; thermal management challenges, not to mention innovations in engine design, though not insurmountable, could be wildly difficult to overcome.

Perhaps the biggest challenge, however, is today’s political climate and the Trump administration’s interest in slashing federal spending through the Department of Government Efficiency.

Charged with finding and eliminating waste, DOGE aims to streamline huge swaths of the federal government. And, perhaps most problematic for a project like the SR-72, Elon Musk, the head of DOGE, is not a fan of manned fighters.

In today’s era of intense cost-cutting across the board, a project like the SR-72 might not stand a chance.

The SR-72 Math Problem: The Cost Might Make It Possible to Be Cut

Musk has previously expressed skepticism toward traditional manned fighter platforms, advocating instead for the development of unmanned and cost-effective aircraft. His emphasis on technological innovation and efficiency aligns with his broader vision of modernizing defense capabilities while minimizing costs.

Why spend billions on a plane like the SR-72 if Musk thinks it is old and obsolete already?

Elon Musk has previously expressed strong skepticism for traditional manned fighter platforms, advocating instead for the development of unmanned and cost-effective aircraft. Musk took to X late last year to express his disdain for the F-35 stealth fighter project, calling those behind the design “idiots.”

In another Tweet, Musk said the F-35 design was “broken at the requirements level, because it was required to be too many things to too many people.”

He added that “this made it an expensive & complex jack of all trades, master of none. Success was never in the set of possible outcomes. And manned fighter jets are obsolete in the age of drones anyway. Will just get pilots killed.”

Vocal though Musk has been against the F-35 stealth fighter platform, there might be an exception made for extremely high-end, high-performance aerospace projects like the SR-72.

A Potential Soft Spot?

Interestingly, however, Musk has shown an unusual interest in the A-12 Oxcart project, the predecessor to the SR-71. His interest came out in, of all ways, the name of one of his children, who he named X Æ A-12 Musk. This suggests that Musk may have a soft spot for aerospace projects like the SR-72, despite being vocal about slashing federal spending.

If it can be realized, the SR-72 would be a significant advancement in aerospace technology, a considerable step above the SR-71, and offer significant reconnaissance capabilities. However, the development of such an aircraft comes at a politically precarious time.

With federal spending under intense scrutiny from the Department of Government Efficiency, striking a balance between cost reduction and the pursuit of cutting-edge technology will be difficult.

However, given the previous interest Elon Musk has indicated in the predecessor project of the SR-71 offers a glimmer of hope: as an admirer of advanced aerospace projects, Musk may find himself a proponent of the SR-72 project and able to navigate today’s delicate political landscape.

About the Author: Caleb Larson

Caleb Larson is an American multiformat journalist based in Berlin, Germany. His work covers the intersection of conflict and society, focusing on American foreign policy and European security. He has reported from Germany, Russia, and the United States. Most recently, he covered the war in Ukraine, reporting extensively on the war’s shifting battle lines from Donbas and writing on the war’s civilian and humanitarian toll. Previously, he worked as a Defense Reporter for POLITICO Europe. You can follow his latest work on X.