America's Hypersonic Aircraft Has Been an Open Secret Since 2007. China Used the Intel to Get Ahead

The U.S and China have a lot of unresolved issues, all related in one way or another. The technology war between the two countries is one of the most talked about. There’s also the trade war, with recent episodes such as the U.S. tariffs on Chinese electric cars. But let’s not forget the space race—with China having just reached a milestone on the Moon—and, of course, the arms race.

In this race, nothing is faster than a hypersonic aircraft, and both countries are competing to see who gets a military aircraft capable of traveling six times the speed of sound. The U.S. contender? The promising and equally mysterious Lockheed SR-72, which has reportedly been in development for over 10 years.

Back to the past. Lockheed SR is a mighty name. The SR-71 Blackbird flew from 1964 to 1998, when the U.S. Air Force retired it. It was the fastest aircraft in the world for decades—without being a rocket plane, of course. The SR-71 could fly at an altitude of 79,000 feet and reach a speed of 2,200 miles per hour. It reached Mach 3, which means it was flying at three times the speed of sound.

The Blackbird’s mission was long-range strategic reconnaissance. It was part of a secret program and designed to evade radar. However, with time, radar improved, and the hypersonic aircraft was no longer infallible. It was also huge and heavy (over 30 tons), which made its speed even more incredible. In addition, the engineers behind the Blackbird used titanium alloy as the primary material and quartz for the windows to resist elevated temperatures when flying at that speed.

But it had problems: The cabin temperature was extremely high, and the fuselage had “cracks” that closed when the plane flew. It lost fuel, so the aircraft had to make a flight and refuel in the air with the cracks already sealed because of the metal's expansion due to the heat. Then, it was ready to work. By the way, it was built in the middle of the Cold War with Soviet materials thanks to U.S. trickery.

The SR-72. All types of aircraft are entering the hypersonic race, but the one that could worry the U.S. is a hypersonic military aircraft from China. In 2007, Lockheed Martin allegedly proposed the development of a new generation. Even then, the goal was to reach Mach 6 (4,000 mph), so the aerospace and defense manufacturer had been supposedly working with other companies for several years to achieve this hypersonic propulsion system.

The first years of the SR-72 were strange. In 2013, there was already news about the successor of the SR-71 Blackbird and speculations about dimensions like those of the previous generation: same range and 99 feet long. In November of that year, General Mark Welsh, chief of staff of the Air Force, stated that the military was interested in something like the SR-72 but had not talked to Lockheed Martin.

The U.S. was particularly interested in hypersonic technology so the enemy would have no reaction time. However, the problem was that existing materials would have caused the aircraft to disintegrate at the hypersonic speeds they wanted to achieve. In 2014, NASA awarded a contract to develop the plane’s propulsion system. Finally, in 2017, Lockheed Martin announced that the SR-72 would begin development in the 2020s.

China speeds up. The U.S. is the country that invests the most in its military. Still, China is slowly catching up, and that includes investment in nuclear weapons as well as in other areas. The country is building a fleet of aircraft carriers and clones of U.S. fighter jets. It has copied the U.S. Apache and, most importantly, taken the lead in developing a technology that the U.S. has curiously stalled.

But beyond copying designs, Chinese researchers have been hard at work, so much so that they claim to have engines that reach Mach 9 (about 6,900 mph), want to jump to Mach 16 (12,430 mph), and are even tinkering with plasma to make their fighters invisible. But wait, if heat is a problem, how do they plan to get to such unimaginable speeds? Using a ceramic armor called 9PHEB. It can maintain its structure up to temperatures of 1,832 degrees Fahrenheit, with a loss of integrity of 2.4% at 3,632 degrees Fahrenheit.

Top Gun: Maverick. The U.S., supported by DARPA experts, can't explain how China has developed all this technology—plus hypersonic weapons—quickly and under the radar. In 2017, Lockheed Martin’s vice president Rob Weiss commented, “We’ve been saying hypersonics [are] two years away for the last 20 years, but all I can say is the technology is mature and we, along with DARPA and the services, are working hard to get that capability into the hands of our warfighters as soon as possible.”

In 2018, the company claimed that it scheduled the SR-72’s first test flight in 2025 and that it would use hypersonic missiles. But in the wake of China’s advances, was a push to hype the aircraft necessary? Intentionally or not, the SR-72 is said to have made a cameo in Top Gun: Maverick. In the movie, it’s called Darkstar, which was actually built by Lockheed Martin for filming.

It’s a statement of intent by easily surpassing the Mach 3 speed of its predecessor and reaching Mach 10. The SR-72 doesn’t seem that ambitious, but hey, it’s a movie. Here’s the scene it comes out in:

Mach 6 is expensive. Top Gun producer Jerry Bruckheimer said a while back that someone in the Navy told him that China thought the Darkstar was real, so it redirected one of its satellites to photograph it. Who knows if this is part of the movie’s narrative, but it’s clear that we can take this plane as a preview of what Lockheed Martin is preparing.

And what’s also clear is that overcoming all the challenges of the hypersonic program will cost a lot. The development of hypersonic systems, including propellants and weapons, had been somewhat dormant in the U.S. budget. However, it has returned to the forefront after Russian and Chinese advances. The Pentagon’s budget request for hypersonic research was $3.8 billion for fiscal year 2022. It rose to $4.7 billion in 2023, and the number has skyrocketed by 2024: $11 billion for long-range weapons, which includes supersonic.

Target: 2030. Either way, if the plans of the U.S. and Lockheed Martin go well, the secret SR-72 program should come out sometime next year when the first test flights, planned for years, will take place. The goal is to have it ready by 2030. We’ll see what happens, as delays have been the pattern in recent U.S. projects.

Images | Top Gun: Maverick

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