Friday, March 11, 2022

How the Javelin Works

Journalists reporting on the war in Ukraine frequently mention the use by Ukrainian forces of a weapon called the Javelin which has been very effective, apparently, against Russian armored vehicles like tanks and armored personnel carriers. Ross Pomeroy at RealClear Science writes a helpful explanation of how the missile works. Here are some excerpts from his piece:
"This weapon allows a single soldier to target and destroy even the most heavily armored main battle tank with an almost guaranteed kill rate, at great range and with minimal risk," Army Capt. Vincent Delany wrote of the Javelin for West Point's Modern War Institute.

With the Javelin, a soldier using the portable, reusable Command Launch Unit (CLU) looks through an infrared sight to locate a target up to an incredible 2.5 miles away.

When the user spots a target, he operates a cursor to set a square around it, almost like cropping an image. This is then sent to the onboard guidance computer on the missile itself, which has a sophisticated algorithmic tracking system coupled with an infrared imaging device.

When the missile locks on to the target, the operator can launch the self-guided weapon and quickly relocate or reload to fire another missile at a different target.

The Javelin originally debuted in 1996, bearing a couple remarkable innovations. For one, it offers a "soft launch." David Qi Zhang of the Rensselaer Polytechnic Institute explained what that means in his Master of Engineering thesis on the Javelin.

"The first motor... produces enough thrust to launch the missile out of the tube and a safe distance away, but is completely burned before the nozzle left the tube, leaving no exhaust to hit the operator. The flight motor then ignites to propel the [missile] along its attack path," he wrote.

A second innovation of the Javelin is that it strikes from above. The missile rises high into the air, up to 490 feet, then blasts down on its target from a steep angle, striking the top of an armored vehicle or tank, where the armor is typically weakest.
Russian tanks are not helpless against the Javelin. Most are equipped with explosive reactive armor. When struck by a penetrating weapon like a missile, the armor detonates, blasting a metal plate outwards to damage the missile's penetrator and prevent it from piercing the tank's main armor.

The Javelin overcomes this by having tandem warheads, one to deal with the reactive armor plate, and the second to impact the tank's armor itself.

Modern Russian tanks are also equipped with a radar system called Arena, which detects incoming missiles and automatically fires a wide burst of projectiles to destroy or redirect them. But here, again, the Javelin reigns supreme, Delany says.

"The Javelin can defeat Arena while in top-attack mode, due to the missile descending from too steep an angle for the system to engage properly," he wrote.

Ukraine had been shipped roughly 77 launchers and 740 missiles before Putin invaded. Many, many more of each are now on the way courtesy of the U.S. and European allies. According to an article at NDTV as of a week or so ago at least 280 Russian armoured vehicles had been destroyed with the American Javelin missile, out of 300 shots fired.
By now thousands of these weapons are in the hands of the Ukrainian armed forces, which is one reason why the Russians aren't advancing very quickly on the ground but are instead bombarding cities either from the air or from a safe distance away with artillary.

Here's a chart released by Ukraine showing Russia losses thus far in the war. Whether the Ukrainians have inflated the numbers or not is hard to tell:
The chart appeared in an article in The Sun which has some other information on the war.