The merits of speed in combat are quite difficult to capture and seemingly not to be underestimated

By Kris Osborn, Warrior

The SR-72  “Son of Blackbird” is faster and more capable than its “hypersonic” SR-71 predecessor as it can reportedly reach speeds up to Mach 6, nearly double the Mach 3.3 speed of the initial “Blackbird.”  

The high-speed SR-72 plane can, according to some estimations, outrun some missiles and weapons systems, due in large measure to its turbine-based combined cycle (TBCC) engine. This engine, as discussed in a 2023 essay in Warrior, blends traditional jet propulsion for take-off with a scramjet engine for hypersonic travel designed to manage performance across a range of speeds and ranges. 

The merits of speed in combat are quite difficult to capture and seemingly not to be underestimated, as a surveillance aircraft traveling at speeds of Mach 6 would of course have greater success eluding air defense systems. A platform at these speeds would not only be difficult to “target” with “engagement radar” for a precision strike but would also fly from one radar aperture or field of view to another so quickly that air defenses would be challenged to establish a continuous “track.”  

SR-72 vs Air Defenses 

As part of these higher-threat speeds, the SR-72 could mitigate or neutralize advanced air-defense technologies able to “network” to one another and hand-off or pass along target specifics as the aircraft transited from one field or regard to another. Advanced air defenses, such as the Russian S-400 and S-500 for example, are increasingly capable of newer kinds of digital networking designed to enable a node in one location to pass information to another across otherwise disaggregated geographical boundaries. 

Yet another area of potential advances with hypersonic flight pertains to air “boundary layer” as well as thermal management.  The Army Research Laboratory, and likely the other US services as well, are experimenting with novel combinations of composites and particles to best identify new materials better able to withstand the “heat” of hypersonic flight.  Scientists and weapons developers say “thermal management” is the largest and most difficult challenge when it comes to “sustaining” hypersonic flight. It is not always possible for a projectile or platform to maintain its structure and travel through the unprecedented “heat” generated by hypersonic flight. 

“The SR-72 incorporates advanced materials to withstand extreme thermal stresses, likely involving carbon-carbon composites, which are a step beyond the SR-71’s titanium skin designed for heat dissipation at high speeds. Furthermore, the SR-72’s design emphasizes not just speed but also stealth and operational versatility, integrating advanced avionics and possibly even AI-assisted systems for autonomous operations, which were not features of earlier hypersonic aircraft,” a 2023 essay from Warrior states. 

Airflow & Heat Management

Many of the specifics of the technologies built into the SR-72 are not likely to be available, yet the Air Force Research Lab explains they are working on “boundary layer phenomenology” related to hypersonic flight.  Senior ARFL weapons developers explain that the intent with air flow surrounding a hypersonic platform or projectile is to enable a smooth or “laminar” airflow. This enables a more stable flight path or trajectory for the hypersonic object, meaning it is not thrown off course by “turbulent” air flow passing over during flight. Turbulent air flow, AFRL scientists told Warrior, can cause molecules surrounding the vehicle to shift position in flight, something which both generates heat and disrupts flight path and targeting.

***This essay first appeared in 1945****

 Kris Osborn is the President of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a highly qualified expert in the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.