The United States is finally building a successor to the incredible SR-71 Blackbird. Lockheed Martin’s highly secretive Skunk Works is actively working on a highly secretive aircraft, the SR-72 Darkstar. And despite going over budget by just a smidgen ($335 million), the Darkstar seems ever closer to reality.
The SR-72, also known as the “Son of Blackbird,” is poised to succeed the SR-71 Blackbird, the fastest surveillance plane of the Cold War era. With hypersonic speeds, the SR-72 will give the Air Force the ability to penetrate near-peer rivals’ defenses, such as China’s advanced anti-access/area-denial (A2/AD) bubbles.
Image of SR-71 Spy Plane. Image Credit – Creative Commons.
However, the SR-72 differs from other stealth aircraft. The Darkstar’s speed could outpace detection systems. Unlike the SR-71, the Darkstar is capable of delivering critical strikes and returning safely.
The potential weaponization of the SR-72 would counter China’s advancements in radar and hypersonic weaponry, helping the U.S. maintain aerial superiority.
Is Stealth Getting Obsolete?
China has been relentless in developing stealth detection technology and has reached a point where the American commitment to stealth capabilities might be useless in a future conflict.
Artificial intelligence (AI) or next-generation quantum radar could make stealth planes completely visible to Chinese anti-aircraft systems long before they reach the range of potential Chinese targets.
But the SR-72, while stealthy, wouldn’t rely on its stealth to avoid Chinese defenses. It would depend on pure speed. It could simply outfly whatever systems a near-peer rival, like China, has developed, deliver its payload, and continue to fly safely without incident.
Speed, and More Speed For The Darkstar:
The speed generated by conventional turbofan power accelerates up to supersonic speeds. Then, the aircraft transitions from turbofan power to a much more exotic dual-mode scramjet, enabling it to achieve speeds exceeding Mach 6 (4,603.61 mph).
This would protect the aircraft without any stealth features.
SR-72. Image Credit – Artist rendering.
The SR-72 can fly from New York to Los Angeles in 30 minutes. It is much faster than the Blackbird’s speed of Mach 3.56 (2,731.478 mph), although some Blackbird pilots claim it could fly faster.
Is the Darkstar Practical? Pros and Cons:
Hypersonic Speed: The SR-72’s possible ability to travel at Mach 6 (4,603.61 mph) would enable rapid strike missions and allow it to outmaneuver air defenses. The turbine-based combined cycle (TBCC) engine, which pushes out that enviable speed and thrust ratio.
It integrates scramjet technologies for better performance. The TBCC enables subsonic flight, and the scramjet makes attaining a Mach 6 speed easy.
Global Reach: The high speed and altitude of the SR-72 could enable global strike capabilities, allowing it to reach any location on the globe in a short timeframe. It can fly over a continent in 30 minutes at an altitude of 85,000 feet.
The unmanned Darkstar could make 9G turns and wouldn’t require in-flight refueling. The high altitude makes it very difficult for advanced air defenses like the S-400 and S-500 systems to destroy it.
ISR and Strike Platform:
The SR-72 could be utilized for both intelligence, surveillance, and reconnaissance (ISR) and for delivering hypersonic weapons, according to a report from Aerocontact.
The Darkstar could also utilize hypersonic missiles that are nuclear-tipped, making it a possible addition to the U.S. nuclear triad.
Thus, it is a strategic, intercontinental asset that can spy with the best of them and deliver strike capabilities to important enemy targets such as hardened missile silos and radar installations.
Airframe Heat Challenges:
The extreme heat generated at hypersonic speeds poses a significant challenge to the SR-72’s airframe, requiring innovative materials and technologies.
Maya Carlin wrote recently, “At speeds greater than Mach 5.0, the resulting high temperatures can melt conventional metallic airframes. To rectify this, engineers are researching alternate composites including high-performance ceramic, carbon, and metal mixes.”
The heat would reach more than 500 degrees Fahrenheit on the aircraft’s external surfaces
Air Defenses Have Evolved:
While speed is a significant advantage, modern air defense systems are also advancing, which could make it difficult for the SR-72 to penetrate defended airspace.
China and Russia have been working hard to improve their air defenses, which are much more advanced than in the Blackbird days.
Today, every country is working on developing hypersonic missiles for air defense and offensive scenarios.
High-speed missiles, like the British Starstreak, can reach speeds of Mach 3.5. Other modern interceptors could pose a significant threat even to a hypersonic aircraft.
Stealth Considerations:
Stealth technology may be compromised by the extreme heat generated at hypersonic speeds, impacting the SR-72’s ability to evade detection.
However, engineers at Skunkworks have minimized the radar cross-section and created stealth coatings that make enemy sensors ineffective when spotting the Darkstar.
Armaments:
Existing payloads may be inadequate for the SR-72’s speeds, necessitating the development of new hypersonic weapons. This would raise the cost of the aircraft even higher than what is expected.
“Hypersonic aircraft, coupled with hypersonic missiles, could penetrate denied airspace and strike at nearly any location across a continent in less than an hour,” Brad Leland, Lockheed Martin’s hypersonics manager, said in a Lockheed Martin press release that has since been taken down.
The SR-72 could become a strategic, intercontinental aircraft that can gather intelligence, deliver strike capabilities to essential enemy targets, and escape while the enemy is powerless to stop it.
While modern air defense systems are much better today, the Darkstar would stay well ahead of them. It is a practical solution to the problems they face.
About the Author:
Steve Balestrieri is a 19FortyFive National Security Columnist. He served as a US Army Special Forces NCO and Warrant Officer. In addition to writing for 19FortyFive, he covers the NFL for PatsFans.com and is a member of the Pro Football Writers of America (PFWA). His work was regularly featured in many military publications
