Revelations by the Financial Times that China tested two hypersonic weapons in recent months have sparked alarm among US defence officials because it suggests Beijing is making faster progress than expected on a new class of missile defence system-busting arms.
One test in particular, conducted on July 27, has intrigued US government scientists. China launched a Long March rocket that used a system to propel a highly manoeuvrable, nuclear-capable glider into orbit, allowing it to move towards its target at five times the speed of sound, according to people with knowledge of the test who declined to be identified because the information is classified.
An unknown element in the test has prompted US scientists to suspect Beijing may have achieved a new military capability, suggesting that China is making even quicker progress developing weapons that could shift the balance of power between the two countries.
Here is a guide to what is known about the weapon and the other hypersonic arms under development around the world.
What’s the technology behind the Chinese test?
During the Cold War, the Soviet Union developed an orbital bombardment system that could carry a nuclear weapon into orbit at a lower trajectory than a traditional fixed-trajectory ballistic missile. The traditional device is sent to outer space, where it can be detected and intercepted.
Called a “fractional orbital bombardment system”, or Fobs, by Moscow, it was designed to evade missile defence systems. The term “fractional” was used to back up Russia’s claim that the weapon did not breach the 1967 Outer Space Treaty, which bans the deployment of nuclear weapons in space.
However, the Chinese version of the system that was tested last summer comes with a twist: a so-called hypersonic glide vehicle (HGV), which can travel at more than five times the speed of sound (hence the hypersonic label) and go much further than a ballistic missile once it has detached from the rocket.
The glider’s lower trajectory, speed and ability to manoeuvre as it approaches its target make it much harder to intercept. It differs from hypersonic cruise missiles. which are powered by high-speed engines that use oxygen in the atmosphere for propulsion during flight — so-called air-breathing engines. A glider can travel further and more quickly than a hypersonic missile because it is boosted into orbit on a powerful rocket.
“The easiest way to think about [the glider combined with the Fobs] is to imagine the space shuttle, put a nuclear weapon in the cargo bay and forget the landing gear,” said Jeffrey Lewis, a nuclear weapons expert at Middlebury Institute of International Studies at Monterey.
Who is developing hypersonic weapons?
The US, Russia and China are leading the development of hypersonics. But notably, only China and Russia are developing nuclear-capable gliders.
Other nations, including the UK, France, Australia, India, Japan and North Korea, are also working on the technology. Meanwhile, Iran, Israel and South Korea have conducted basic research, according to a recent report by the US Congressional Research Service.
Funding for hypersonic weapons in the US has increased in recent years, in part due to advances in these technologies in Russia and China. Russia recently said it had test-launched a hypersonic missile from a submerged submarine for the first time.
The Pentagon’s recent budget request for hypersonic research in 2022 is for $3.8bn — up from its $3.2bn request for 2021. The Missile Defense Agency has additionally requested $247.9m for hypersonic defence.
Many of the world’s largest defence companies, including America’s Lockheed Martin, Northrop Grumman and Raytheon as well as Britain’s BAE Systems, have been investing in hypersonics and are working with governments to test and develop different capabilities.
Why might China want this technology?
Fractional orbital systems can evade US early warning systems. They can also fly over the South Pole, putting them out of reach of the Pentagon’s interceptor missiles, which are based in Alaska.
Some experts have questioned why China would develop this capability since US missile defences are tailored to repel states such as North Korea that have relatively small long-range missile capabilities and are not designed to overcome large attacks from countries like China.
David Wright, a nuclear weapons expert at the Massachusetts Institute of Technology, said China knew it could overcome US missile defences, but it might want to convince American officials who believe their systems are more capable that China has other ways to attack. “The other argument is that they don’t want to be caught out in the future,” said Wright, referring to the US continuing to develop its ballistic missile defence systems.
Joshua Pollock of the Middlebury Institute of International Studies said China might also be thinking about how to counter the sea-based missile defence systems the US has placed on Aegis ships, which are deployed in the western Pacific. He added that the manoeuvrable gliders would help evade those systems.
What does this mean for the balance of military power between the US and China?
Speaking to the military newspaper Stars and Stripes in Germany this week, Admiral Charles Richard, the head of Strategic Command who oversees US nuclear forces, said China could “now execute any possible nuclear employment strategy”.
“We should be open to the reality that China is also capable of technological innovation,” Lewis said. “I would be careful about exaggerated characterisations that may help excuse a mundane intelligence failure. If we say some innovation is impossible to imagine, then no one is really responsible for missing it.”
Some experts have likened the investment rush into hypersonics to an arms race, as countries seek to match the capabilities of others. Cameron Tracy, a research scholar at the Center for International Security and Cooperation at Stanford, said while the US was spending a “great deal of money . . . on these weapons”, their role was not clear.
“The US Department of Defense has not articulated a clear role for what these weapons are meant to do, what mission they are going to fulfil that existing missile technologies couldn’t. That is a big open question on the US side — are we just building these because Russia and China are?” he said.
China said it had tested a space plane, not a weapon. But the timing of that plane launch in mid-July does not coincide with the July 27 test the FT revealed, which was not announced by Beijing.
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