Why the hypersonic missiles arms race is spooking the west

Speed is the new stealth in the contest to fly too fast for rival air defences to spot.

North Korean artillery conducts an ultra-large rocket salvo firing drill this week. Picture: KCNA via AFP

When an American B-52 bomber took off from Andersen Air Force base on Guam on Sunday and then launched a new missile over the Pacific, it sent a strong message to China.

The test of the hypersonic weapon, designed to fly at five times the speed of sound, was ­arguably a statement of “anything you can do …” as part of an arms race to fly faster, and with more manoeuvrability, than air defences can cope with.

In theory, hypersonic weapons can carry nuclear warheads as well as conventional ones. Beijing has already managed to ­develop such a weapon, and, with Russia and North Korea also claiming to have the capability, the West is keen to catch up.

While the US Air Force ­announced the successful test of its own Air-launched Rapid ­Response Weapon as a final step in its development on Tuesday, it did not disclose details, such as the exact speed of the weapon.

In past tests the ARRW has flown at Mach 5, making it difficult for current air defence systems to track and intercept, but details are being closely guarded as rival powers also make their own claims.

North Korea, for example, boasted on Wednesday that it had successfully tested a solid-fuel ­engine for its new intermediate-range hypersonic missile.

State media suggested there has been notable progress in Pyongyang’s efforts to develop a more powerful, agile missile that could be capable of hitting distant targets in the region including Guam, more than 3000km away.

B-52 Stratofortress crews participated in hypersonic weapon familiarisation training at Andersen Air Force Base, Guam, last month. Picture: US Air Force via AFP

North Korean leader Kim Jong-un oversaw the latest test, at the Sohae Satellite Launching Ground in the country’s northwest, the official Korean Central News Agency said.

Experts said it was difficult to know what North Korea had achieved in reality, ­although it had talked about developing ­hypersonic glide vehicles as early as 2001.

Russia, likewise, has previously claimed to have used its air launched Kh-47M2 Kinzhal hypersonic missile, also referred to as the “Dagger”, to strike targets in Ukraine. British sources have expressed doubts over whether the missiles are truly ­hypersonic weapons.

It is China’s development of ground, air and sea-launched ­hypersonic variants that is causing most alarm in the West.

A UK defence intelligence source, briefing on the development of hypersonic weapons, said China had been the only country to successfully deploy weapons that would meet the definition of being capable of Mach 5. “Speed is the new stealth, it is the way to evade radar defence systems,” he said, adding that such weapons were considered particularly dangerous.

China’s DF-27, for instance, is an intermediate-range ballistic missile which can travel more than 5000km and its hypersonic glide warheads can swerve to avoid ­detection or interception.

There are two main types of hypersonic weapons: glide vehicles, which are launched from an aircraft – or into space on a rocket – before gliding to their target, and cruise missiles, which have engines that use the air’s oxygen and produce thrust during their flight, allowing them to cruise at a steady speed and altitude.

Unlike ballistic missiles, the hypersonic cruise missiles do not follow a predetermined, arched trajectory. They can change course in flight, which makes them harder to track and destroy because the enemy does not know what the target is.

The glide vehicles, such as the ARRW, typically fly at lower altitudes, so as to not be visible to early warning systems. “This can pose challenges because the ­opponents have less warning,” the source said.

Douglas Barrie, a senior fellow for military aerospace at the International Institute for Strategic Studies, said both types of hypersonic weapons would “increasingly feature in the inventories of the most advanced armed forces, but likely for specific and high-value target sets, given the development and procurement costs of both classes of system”.

Australia, the US and the UK are working together as part of the AUKUS pact to develop ­hypersonic weapons and counter measures that could help allies defend against such attacks.

However experts in the field believe that the best way to defeat hypersonic weapons in future would be to target the bases they are launched from because, by the time they are in the sky, it could be too late.

THE TIMES