WHY THIS MATTERS IN BRIEF
Trying to destroy one hypersonic weapon is hard enough – trying to overcome a swarm is currently impossible …
Hypersonic weapons, which because of their speed and agility could change the balance of global military power, are now in the early stages of deployment, but as the first generation of weapons are being fielded chinese researchers recently announced they’re already working on the next generation of hypersonic weapons which work together in swarms to overcome and obliterate their enemies defenses. Needless to say such swarms would be far more dangerous than the individual missiles that comprise them, and they’d multiply the power of the high-speed weapons.
Hypersonic missiles, cruise missiles that travel inside the atmosphere at more than five times the speed of sound (over 4,000 mph) are shaping up as the next wave of military innovation. While they may be slower than ballistic missiles, their comparatively low-level flight means there is much less warning of hypersonic missiles’ arrival, and they are far more challenging to intercept. They could deliver nuclear warheads or deliver devastating surprise attacks against aircraft carriers or airbases. It’s no surprise therefore that China is developing them to counter US superiority and the Pentagon is devoting so much effort to defend against them.
A new study from the Beijing Institute of Technology titled ‘Network for hypersonic UCAV swarms’ seeks to multiply the power of hypersonic weapons by having them work together. UCAV is short for Unmanned Combat Air Vehicle, a term usually employed for armed drones, but applied in this case because they are more than missiles – the members of the swarm will carry sensors and communications.
The benefits are a shared situational awareness, for example alerting other swarm members where defenses are located, being able to simultaneously hit targets with multiple weapons coming from different directions, and co-operatively searching for elusive or moving targets. A swarm could comprise several waves, with each one advising the next which targets have already been destroyed or where holes have been made through defenses.
Ultimately the swarm will make its own decisions about where to go and how to attack.
“The hypersonic UCAV swarm provides rewarding and long-desired tactical utility,” notes the paper. “It can carry out missions such as saturation attacks, situational awareness sharing, distributed cooperative guidance, cooperative path planning, cooperative searching, and eventually, the cooperative autonomy.”
Cooperative autonomy will mean that the swarm itself is in control rather than being directed by a human, something which may become increasingly important given the fast pace of events at five times the speed of sound.
Significantly, the report repeatedly quotes American work rather than Chinese as its inspiration, giving the impression that China is simply responding to US projects already under way. For example:
“The US Army recently announced it was working toward autonomous coordination capabilities. In 2017, the missile multiple simultaneous engagement technologies (MSET) program was initiated, which was envisioned as a suite of technologies providing supervised autonomous terminal engagement of multiple missiles against various targets and inter-group communication for shared situational awareness.”
This glosses over the detail that MSET is a small-scale tactical system, not a strategic weapon with hypersonic missiles. The Chinese researchers are essentially trying something similar, but on a gigantic scale. This makes things far more challenging. The paper acknowledges that “high mobility, dynamic topology, large geographic coverage, and hostile environments” need to be overcome.
Their solution is a version of a mobile ad-hoc network or MANET, like the one used in the US Army’s IVAS project, in which communication nodes spontaneously join with their nearest neighbours to pass on data. Ramdomisation and spread spectrum will keep the network secure and make it difficult to jam, and advanced beamforming antennas provide long-range, tight-beam signals. The network will probably require very short wavelength “millimeter wave” technology in the 30—200 GHz range, potentially overlapping with some 5G systems. Novel software is required to tie it all together efficiently.
The paper is more about asking questions than providing answers, which would be unlikely in an open-source publication, and the hypersonic swarm is clearly many years in the future. It does, however, give a little insight into what Chinese military planners might have in mind:
“With the help of good self-organizing technology, a group of well-organized, low-cost UCAVs can often produce more powerful combat capabilities and effects than a single excellent UCAV. Take saturation attacks as an example: To gain operational advantages, each round of attack requires multiple collaborating units to hit the target simultaneously … Such saturation attacks have been devised as an effective countermeasure that can survive the threat of interceptors and penetrate defense systems.”
While the US is starting work on defenses against hypersonic weapons, it’s clear that the Chinese are already working out ways to overwhelm those defenses and stay at least one step ahead …