The world’s superpowers have developed an array of hypersonic missiles that can travel across the world faster than Mach 5, or 3,800 miles per hour.  These weapons signal almost immediate weapons response capabilities for the countries that have them. So much so that developing new hypersonic tech is creating a sort of new arms race around the world.

Before we can understand how hypersonic missile tech is causing a new global arms race, we need to understand how hypersonic missiles work.

How hypersonic missiles work

Hypersonic weapons essentially combine the speed of ballistic missiles with the maneuvering capabilities of cruise missiles. They travel over 6115 kilometers per hour making them hard to track compared to traditional missile tech. One of the biggest advantages to modern hypersonic missiles isn’t speed though, it’s the added maneuverability at these high speeds that makes them so practical as an instant defense.

While hypersonic missile tech is key for rapid accurate delivery, the most important part of any weapon is the payload. Hypersonic weapons can deliver conventional or nuclear payloads essentially anywhere in the world within minutes. Though due to their propulsion techniques, they need to be launched from vehicles traveling at supersonic speeds, like jets or bombers.

Behind this impressively dangerous hypersonic technology is something called a supersonic combustion ramjet, otherwise referred to as a scramjet system. 

Scramjet engines collect oxygen from the atmosphere as the travel to mix with hydrogen fuel, which creates the combustion needed for hypersonic flight. Through the design of the scramjet inlet, the air is forced in and compressed before it is mixed with hydrogen fuel, which then ignites, and is directed out of the nozzle in the back. It’s actually a rather simple process compared to some other combustion techniques.

Regular ramjet engines utilize liquid oxygen and hydrogen fuel, but this, in turn, makes the vessel very very heavy. The best example of this engine technology would be the now-retired Space Shuttle. Herein lies the advantage to scramjet engines, they only need to carry hydrogen, eliminating the oxygen storage, which is proportionately 70% of the fuel space used in ramjet rockets.

So then, why wouldn’t you just always use a scramjet rocket? Mostly because in order for the engine to work, it needs to be launched at supersonic speeds. This is necessary to kickstart the air-fuel mixture to begin combustion. Once the rocket reaches supersonic speed, it’s launched with a small booster engine that gets it up to Mach 5 and a preferred minimum altitude of 100,000 feet.

This necessary means of launching has made hypersonic missiles somewhat impractical, but new tech is being developed.

New developments include dual-mode ramjet engines, which use ramjet propulsion to get the craft up to speed, where it then switches over to scramjet mode. 

Conventional ballistic missiles have to be launched at steep trajectories so that they don’t burn up on launch and reentry into the earth’s atmosphere. Whereas hypersonic missiles can glide atop the atmosphere and still utilize their engines to accelerate and steer.

This ability to travel at high velocities and high altitudes for extended periods of time make hypersonic missiles much more advantageous when concerned about range. It also allows them to bypass most modern missile defense systems. Finally, as we’ve mentioned, hypersonic missiles can maneuver in flight so their trajectories aren’t set. This is in sharp contrast to the highly defined and steep trajectories of traditional ballistic missiles.

With a basic understanding of how hypersonic missiles work and why they are so advantageous to militaries around the world, we begin to get a clearer picture about why they might be kickstarting an arms race between superpowers. 

The hypersonic arms race

Currently, the U.S., China, and Russia are testing hypersonic missiles that can deliver various types of payloads. Notably, the U.S. is focusing only on conventional payloads, while China and Russia are developing both conventional and nuclear delivery methods. At least, that’s public knowledge on the matter.

How Hypersonic Missiles Work and Why They're Starting a Global Arms Race
An X-51A WaveRider hypersonic flight test vehicle is uploaded to an Air Force Flight Test Center B-52Source: U.S. Air Force

In the spring of last year, Russian President Vladimir Putin premiered and promoted the country’s new hypersonic weapons. He claimed that the 6 new prototype weapons unveiled would be ready for battle in 2020.

In 2018 as well, China also announced that it had successfully tested hypersonic aircraft, something that the U.S. hasn’t accomplished yet – again, that is known to the public. 

Because China and Russia have both made such massive strides to hypersonic dominance, it has created great tension in the realm of missile arsenals. We now see a race between these three top players in the global war industry to create the best and most-advanced hypersonic missile technologies.

The biggest aspect of this race, however, isn’t the missiles themselves, but rather the defenses against them. The U.S. currently has no means of protecting itself from hypersonic weapons that otherwise travel at more than a mile per second.

To learn a little bit more about the superpower hypersonic arms race, take a look at the short news video below.

Via Interesting Engineering