Another US precision-guided weapon falls prey to Russian electronic warfare, US says

U.S.-provided precision-guided munitions have failed in mission after mission in Ukraine, taken down by Russian electronic warfare. On Wednesday, the Pentagon revealed the latest casualty. 

A new ground-launched version of an air-to-ground weapon developed for Ukraine on a rapid timeline failed to hit targets in part because of Russian electro-magnetic warfare, Bill LaPlante, the Pentagon's acquisition chief, said at an event held by think tank CSIS. 

LaPlante suggested that Ukraine may no longer be interested in the weapon. “When you send something to people in the fight of their lives that just doesn’t work, they’ll try it three times and they’ll just throw it aside,” said LaPlante. 

The weapon LaPlante is referring to is very likely the Ground-Launched Small Diameter Bomb (GLSDB) based on his description, according to Bryan Clark, a senior fellow at the Hudson Institute. 

A Boeing spokesperson did not confirm that LaPlante was referring to GLSDB, but said the company is “working closely with the [Defense Department] on spiral capability improvements to the ground-launch SDB system.” Spiral capability improvements refers to an iterative software development process. 

The GLDSB boasts a range of 90 miles—double the range of the Guided Multiple Launch Rocket System (GMRLS) missiles Ukraine previously used to wreak havoc on Russia’s logistic centers. Funding for the weapon was approved in February 2023, and Ukraine was reportedly using the weapon by February 2024. 

The weapon relies on GPS to navigate to its targets. It also has an inertial navigation system, which navigates to a target by estimating its position through the use of accelerometers and other devices. 

But it is not the first GPS-guided weapon to fall afoul of Russian electronic warfare. 

In congressional testimony in March, Hudson Institute Senior Fellow Daniel Patt said the targeting system for the GPS-guided Excalibur round “dropped from 70 percent effectiveness to 6 percent effectiveness over a matter of a few months as new EW mechanisms came out” in Ukraine. Patt cited the work of Jack Watling, an expert at think-tank RUSI who has traveled to Ukraine multiple times to interview Ukrainian commanders. 

Russian electronic warfare attacks have also directed GMLRS missiles off course, CNN reported last spring. The missiles are similarly guided by a GPS. Russia has also successfully used electronic warfare against GPS-guided Joint Direct Attack Munitions (JDAMs), which are retrofitted aerial bombs. 

Russian electronic warfare on the U.S.’s “more precise capabilities is a challenge,” the commander of the chief U.S. aid coordinating group told an audience in December.

Clark, citing a presentation by Ukrainian soldiers, said the Russians use GPS spoofers to throw off the munitions.  

GPS spoofers work by sending false location data to GPS navigation devices. Because GPS signals are weak, a stronger, false signal can be sent to override the correct inputs. Russia has used GPS spoofing in Ukraine since at least 2018. But advancements in technology mean spoofers can be created cheaply with just a software-defined radio and open-source software. 

The weapons the spoofers are working against, meanwhile, are anything but cheap. A GMLRS missile costs around $160,000, while an Excalibur round can cost as much as $100,000. The GLDSB costs around $40,000. 

However, the weapons were largely designed for a period before spoofers were so easy to set up, Clark said. “You didn't really see the advent of miniaturized, capable GPS spoofers until the last ten years or so, because you needed the micro-electronics to be able to do it,” Clark said. 

Russia has saturated the front with electronic warfare, Clark said. Truck-mounted electronic warfare systems primarily focused on jamming drones are located every six to nine miles on Ukraine’s frontline, he said. 

But Ukraine could use other U.S. munitions that are not susceptible to GPS spoofing, Clark added, citing the Harpoon missile. 

The U.S. could also provide more sophisticated munitions, like the JASSM (Joint Air-to-Surface Standoff Missile), but Clark discounted that possibility because of its range. The Biden. administration has sought to limit Ukraine’s use of longer-range weapons that could target Russia directly.  

Another solution might be to launch weapons from F-16s. Ukrainian pilots currently launch JDAMS from Soviet planes that can’t pass navigational data to the JDAMS, whereas F-16s can, Clark said. Ukrainian pilots are training on F-16s and will be ready to fly them by the end of this year. 

Ukraine can also work to jam Russia’s systems, Clark added. Russia has mostly been using an analog of the JDAM, the KAB, which can also be misdirected by spoofing its guidance system. 

And Ukraine is “fielding some systems now” for electronic warfare targeting of satellite navigation, Clark said. Still, since Russia is targeting civilian populations, “they may not care that much if they get spoofed.”