The new arms race: what is a hypersonic missile?

North Korea claims to have hypersonic missiles. As always when it comes to North Korea, it is difficult to check that statement, but analysts still go off alarm bells. Thats because of that one word: hypersonic.

At the moment, an arms race is underway on this type of missiles. Several countries have developed hypersonic missiles, โ€œbut no one has a good answer yet,โ€ says Patrick Bolder from The Hague Centre for Strategic Studies. โ€œThe current defense systems are not prepared for it.โ€

Speed is everything

In short, a hypersonic rocket is any rocket that goes faster than mach 5: five times the speed of sound. The traditional ballistic missile, which is fired in a large arc, can also achieve these speeds. The difference is that the hypersonic missiles only have to leave the atmosphere for a short time, or even at all.

โ€œThat makes this weapon very interesting,โ€ says safety researcher Danny Pronk of Instituut Clingendael. โ€œWithin the atmosphere, the rockets can maneuver and then they become unpredictable. That makes it difficult to defend against it.โ€

Rockets can reach hypersonic speeds in two ways. A rocket can be launched with a large internal combustion engine, similar to a space shuttle. This briefly leaves the atmosphere, after which the rocket loosens. He then dives back, where he goes to his goal with a sliding system. This allows him to change direction during the flight.

The second variant works like a cruise missile. It has a scramjet engine on board, which takes air at high speeds. It is mixed with fuel, so that hypersonic speeds can be achieved with a relatively light engine. For this, the rocket does not have to fly outside the atmosphere.

Due to the high speeds, the rocket must withstand extreme temperatures: due to the friction with the air, the head needs extra protection, leaving less space for an explosive charge. The current missiles are therefore mainly made to cause damage due to their speed, not by an explosion.

Intercepting more difficult

The fact that the rocket flies lower than similar missiles and can maneuver makes it harder to track down. The current defense systems are prepared for rockets that are either slower, or fly in a larger arc. โ€œYou give the enemy less time to detect, identify, make a decision and fire a defense missile,โ€ says Bolder.

Thats why theres a horror response when a country like North Korea says it has them: no country has a defense system that can track down and intercept hypersonic missiles. โ€œYou always see that in arms races: the advantage is always on the offensive side, then the defense comes only,โ€ says Pronk.

That is not to say that these types of weapons are now decisive in warfare: the technique is costly, extremely complex and the explosive load is often small. โ€œNot many have been made yet, and certainly not enough to make their use valuable,โ€ says Bolder. โ€œOther weapons, such as nuclear weapons, are still enough to deter countries to use them.โ€

Russia is furthest in this technique: that is currently the only country that says it has hypersonic missiles operational. The United States, China and India have done successful tests; France and the United Kingdom are in the development phase.