Are High-Powered Microwave Close-In Weapon Systems Destined For US Navy Ships?

Being able to zap the electronics of incoming boats, aircraft, drones, and missiles is clearly an attractive if not game-changing naval capability.

byTyler Rogoway|
High Powered Microwaves photo


Close-in defense is becoming a very hot topic in American defense circles and in those of foreign powers as well. America's land fighting forces are rushing to address their glaring short-range air defense (SHORAD) gap, while the US Navy is coping with the reality that enemies large and small could successfully take a swipe at one of their surface combatants using everything from small boat attacks, to small drone swarms, to anti-ship missiles, and especially in tight littoral environments. Beyond the existing stalwart kinetic options, directed energy weapons have been seen as the holy grail of close-in naval defense, and it's a space where the US Navy has spent significant development dollars in hopes of moving the technology forward. But lasers aren't the only directed energy close-in weapon system (CIWS) solution—microwave systems may be an equally attractive and more attainable capability in the near term.

The concept isn't too tough to comprehend—a microwave array working like a traditional CIWS system, but instead of spewing cannon shells at its target or firing of a short-range and highly agile missile at it, it emits highly directional busts of high-power microwave energy that are capable of disrupting and even destroying electronics inside the offending enemy weapon system. In other words, it would leave boasts dead in the water and anything in the air—like helicopters, planes, missiles, and especially small drones—careening into Davy Jones' locker or at least malfunctioning to the point that they aren't a threat to the ship itself.

This is exactly the type of device BAE Systems is pitching to the Navy, which they also showcased at this year's Surface Navy Association's symposium. The system leverages the proven Mk38 weapons mount already in use by the US Navy and other navies around the globe, but instead of a chain gun mounted on top it has an array of planar emitters.

The Mk38 mount is in widespread use with the USN. Hundreds of 25mm chain guns use the base, which itself has become a core CIWS capability over the last decade and a half. BAE's microwave system could be mounted on some of these existing mounts or on new ones altogether. , USN

Below deck a microwave generator using high-speed switching feeds this array with an electromagnetic pulse in the microwave spectrum, and the turret is pointed at the target before the pulse is fired off just as a traditional CIWS system would do. The best part about it is that each shot costs a handful of dollars, not thousands or tens thousands or even hundreds of thousands dollars like other CIWS systems. It also has an unlimited magazine, at least physically speaking.

Yet maybe the most attractive thing about a microwave CIWS solution is that using it doesn't result in some sort of projectile, often times of the explosive kind, being shot through the air at high speed, making it far more usable even in very sensitive force protection scenarios, like when a ship is at anchor. Nor does such a system necessarily kill anyone inside a vehicle it is targeted against—making using the weapon against small boats a less than lethal and more attractive proposition. This could dramatically loosen up the rules of engagement in congested waterways, and thus provide a better chance of staving off a potential attack.

BAE says they have successfully tested the capability against various targets, but they haven't pushed it to a naval environment just yet (that's what government contracts are for right?!). Range varies based on the target type, environment, and the configuration of the emitters, but the good thing is that unlike lasers, this system isn't heavily impacted by environmental conditions such as rain, fog, and battlefield obscurants.  

The good people over at put together this great little video of BAE System's booth from the NSA 2018 symposium, the high powered microwave CIWS system is discussed at 1:45 into the video if it doesn't advance automatically for you:

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Supposedly the system is also highly scalable so it can be adapted to different sized surface combatants, although there would likely be a tradeoff in range and strength based on how the mount is configured. One also has to wonder if this type of system could be mounted on commercial vessels as a less-than-lethal option for dealing with piracy. If this can zap a go-fast's engine at a decent distance it could be a way for vulnerable merchant vessels to defend themselves without having to carry traditional weaponry. 

It's hard to image that the US Navy, and other navies as well, wouldn't be interested in this system. The fact that it could be installed on existing or additional Mk38 mounts makes it very attractive as its basic infrastructure is already a known commodity and in the inventory. Above all else it bridges the gap between the Navy's potent electronic warfare suites deployed on its surface combatants and kinetic CIWS options, while also offering a less than lethal option for the increasingly troublesome issue of fending off potential small boat attacks. 

High-powered microwave weapons have a lot of promise, and potential peer-state competitors are actively pursuing the technology, but they remain in the shadowy fringes of military capabilities. Most recently there was big talk and a lot of confusion about the possibility of using the USAF's still experimental microwave pulse equipped cruise missile against North Korea's ballistic missiles, and there has long been talk about systems with similar capabilities as those described by BAE Systems being used on clandestine aerial platforms in war zones in the Middle East and Africa. Even powerful AESA radar sets that are becoming widespread on modern combat aircraft are known to have a secondary non-kinetic attack capability, where their high-power pencil-sized beams of electromagnetic energy could be used to fry enemy missile and air defense-related electronics. So clearly there is something to this technology, but we'll have to see if the Navy will foot the bill to find out how to adapt it as a primary weapon system deployed in a harsh naval environment. But it is worth noting that the service has been willing to do so aggressively with similar weapons concepts in the recent past. 

We also really don't know exactly how effective this can be over various ranges and against different targets, and how vulnerable hardened military platforms would be to such a system. But even if it is only effective against small boats and drones, and less rugged aircraft and some missiles, it would be a major breakthrough in CIWS capability. 

Regardless of the state and capabilities of BAE Systems' particular concept, microwave CIWS capability represents an exciting proposition and it is probably just a matter of when, not if, such a system becomes a fixture on American fighting ships.

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