I’m lumping these together because they all operate on the same basic principle, and are really just different sized versions of the same concept. This idea keeps coming up in a bunch of different sizes and a bunch of different guises.
Antitank missiles today use shaped charge(s) to penetrate armor. We might call this a “chemical energy” method of penetrating armor. More technically, we might call it the Munroe Effect. This is really effective, and doesn’t depend on missile speed. However, there are lots of technologies today to counter this method of armor penetration, including reactive armor (both explosive and non-explosive types), spaced armor, various forms of composite armor, and cage armor. And we can mix and match the above to get some really hard to kill vehicles.
That said, the clever observer will note that most tank guns today use some kind of APFSDS round, a kinetic energy penetrator. Heavy alloy dart moving very fast. Present armor technology makes this a lot harder to defeat than a shaped charge. LOSAT (later renamed KEM) and CKEM would try to apply this same warhead type to an antitank missile. Start with a heavy metal warhead, add a big honking solid fuel rocket motor and fulfill your need for speed.
The missiles were a little different. MGM-166 LOSAT/KEM was 2.85 m long, 16.2 cm wide, and weighed 80 kg. It had a top speed of about 1,500 m/s or 5,000 fps. At this speed, it reached its maximum range in under 5 seconds.
CKEM is the newer, Compact version of the concept. It’s also faster because of rocket motor improvements. It was build in the late 90s/early 2000s to fit a roughly TOW-sized footprint. CKEM was a little longer than TOW at 1.5 m, but matched it’s 15.2 cm diameter. Maximum speed was Mach 6 (about 6,700 fps or 2,047 m/s).
This ends up being a great idea for a number of reasons. We’ve already mentioned that it’s a lot harder to protect a vehicle against APFSDS type rounds. In this case, there is no replacement for velocity. You’ll need heavy armor to stop what’s incoming. Further, a lot of the complicated guidance systems can be done away with. Both missiles had minimal guidance, and relied on lead computations in the launcher to account for any target movement. Given the speeds involved, this is more than sufficient. Finally, being a very fast moving, relatively unfragile thing, it’s a lot harder for modern active protection systems to defeat. All big wins.
Downsides? Well, most of the development and system cost is the motor. We need a relatively small engine that can deliver a lot of thrust very quickly and will also remain stable in storage. That’s not really insurmountable, or a terrible cost driver. Especially when compared to the high-end thermal-imaging based fire and forget systems around these days. The other obvious problem, which doesn’t come up in documentation I’ve seen, is minimum ranges. Even a really high impulse motor will take some time to accelerate that missile up to speed, so there’s going to be a dead zone where the missile will not work as advertised. I’d also expect the motor to be bulky.
Bulk, even for the smaller CKEM, is still an issue. It’s certainly not man-portable. But it would make an excellent antitank missile for vehicles. A JLTV, or a Bradley would make a great carrier vehicle for these. We love tanks, and thus we love antitank missiles. Just like the Russians, who have new tanks. As do the Chinese.
Also, I’d love to see these trialed from helicopters and aircraft. The size isn’t terrible, and the speed should help with the fire control problem.
Verdict: Funding approved by the Borgundy War Department Army Ordnance Board