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Chinese hypersonic weapons test ‘has all of our attention’, US General Mark Milley says

Chinese hypersonic weapons test ‘has all of our attention’, US General Mark Milley says

But the centre – the top Chinese military testing facility, which issues official certificates for deployment of new weapons – requires the rail guns to pass further tests to prove their potential worth in future warfare.

A large number of shots needed to be fired “non-stop at top energy levels” to expose and resolve problems, said Wang and his colleagues in a paper published in domestic peer-reviewed journal Ordnance Material Science and Engineering last month.

The scale and intensity of these tests would far exceed any such tests conducted before, according to the researchers.

The US Department of Defence announced last July that it had decided to halt its rail gun programme to free up resources for the development of hypersonic weapons.

Besides fiscal constraints, a main reason was the need to ditch a gun barrel after about 20 shots because of wear and other damage, according to an American defence analyst.

The US had been a leader in rail gun technology. As early as the Spanish-American war in the late 19th century, the rail gun was proposed by an American inventor to shell Havana from the coast of Florida.

The modern US rail gun programme was launched in 1978 by the Pentagon to counter the former Soviet Union.

After decades of research and more than 1,000 rounds of tests, American researchers achieved a large number of technological and engineering breakthroughs that increased the effective range of the weapon to over 100 nautical miles, with projectiles flying at seven times the speed of sound.

Nonetheless, this range would still put American warships under enemy fire, especially when dealing with an adversary with advanced missile technology, such as China, according to the Pentagon.

Wang said that Chinese researchers had learned a lot from rail gun research in the US and other countries.

For instance, they applied liquid metal to the rail to reduce wear, which had been studied extensively in the West. Some of the models used by Chinese scientists to simulate and analyse the occurrence of damage were also developed by American rail gun researchers.

But Chinese rail guns also had some innovative designs not seen anywhere else, according to Wang.

Unlike most rail guns, the Chinese version would not have an extra device mounted on the muzzle to kill an electric flash. It would use a special coating technology to achieve more stable performance with less damage.

China conducted the world’s first live test in the open sea, with a rail gun mounted on a warship in 2018.

The prototype weapon accelerated a 25kg (55lbs) projectile to Mach 7.3 and hit a target 250km away, according to a paper published in domestic journal Air and Space Defence last year.

What are hypersonic weapons, and why is there a race to develop them?

The Chinese military had also tested a land-based rail gun mounted on a vehicle, according to the study.

Railguns are sophisticated systems, and these experiments suggested that China had achieved breakthroughs in critical components, the paper said, adding that Chinese researchers were also developing hypersonic missiles that could be fired by rail gun and search for a target on the fly.

China has already armed its military with hypersonic weapons, but these are expensive, because they rely on rocket or air-breathing engines to reach five times the speed of sound or faster.

The Chinese navy has said that rail guns could help defend the country’s coast because of their unmatched firing range.

Some other countries, too, have continued investing in rail gun technology. Japan announced last month that it would spend US$56 million this year on development of a rail gun that could shoot down hypersonic missiles.