Ukraine’s GPS-Guided Bombs Work Even When You Jam Their GPS

When the Russian armed forces installed a GPS-jammer in Zaporizhzhia Oblast, in occupied southern Ukraine, the Ukrainian armed forces responded by blowing up the jammer—reportedly with a GPS-guided glide-bomb.

Observers speculated that the Pole-21 was switched off at the time of the attack, apparently last week. “It can be assumed that the [electronic-warfare system] was not operational,” the independent Conflict Intelligence Team observed.

But it’s also possible the Pole-21 was active—and that the American-made Joint Direct Attack Munition that destroyed the jammer relied on its other guidance method.

The JDAM is a GPS-guided bomb. But it also has an inertial guidance system that determines the bomb’s location by knowing its initial location and tracking its movement from that starting point. If the bomb loses the GPS signal, it still can strike its target—albeit with less accuracy.

It’s this other guidance that helped the U.S. Air Force to knock out Iraqi GPS-jammers during the early days of the American-led invasion of Iraq.

In late March 2003, USAF warplanes targeted six Iraqi GPS-jammers that it reportedly acquired from Russia. “Iraq was using the jammers in an attempt to disrupt the guidance system of satellite-guided munitions,” the USAF stated.

A single Boeing B-1 bomber destroyed four jammers on March 22. Two Northrop Grumman F-117 stealth fighters struck the remaining two jammers on March 24.

“I’m also pleased to say they’ve had no effect on us,” USAF major general Victor Renuart said with regard to the jammers. “In fact, we destroyed one of the GPS-jammers with a GPS weapon.” Likely a JDAM.

That the JDAM works even in a jamming environment bodes well for the Ukrainian war effort as Russia escalates its electronic warfare in Ukraine. The Russians aim to thwart Ukraine’s growing arsenal of drones and cruise missiles.

But as long as Kyiv’s forces have at least one precision munition that can barrel right through GPS-jamming, they stand a chance of thwarting this electronic thwarting.