U.S. boosts Ukraine's arsenal with anti-jamming tech for precision bombs

In response to issues with precision weapons based on GPS signals in Ukraine, Americans have ordered the rapid integration of Home-on-Jam (HOJ) guidance heads with JDAM-ER family bombs. Here are the behind-the-scenes details and the significance of this solution in the context of American precision weapon issues in Ukraine.

The American Air Force Life Cycle Management Center (AFLCMC) has awarded Cypress and Scientific Applications and Research Associates Inc. (SARA) a contract valued at approximately £18 million for integrating HOJ heads with modules for JDAM/ER guided bombs.

This solution will allow Ukrainians to use their current weaponry to neutralize Russian electronic warfare systems because a bomb equipped with such a module is guided to the source of interference, similar to how AGM-88 HARM anti-radiation missilesAGM-88 HARM destroy anti-aircraft defence radars.

In recent months, Russians have effectively degraded the advantages of precision weaponry that relies on satellite navigation. This is especially true for systems with low-impact power, such as M982 Excalibur projectiles or GLSDB, where a deviation of several yards makes them ineffective.

Russian electronic warfare systems like R-330Zh Zhitel are responsible for ensuring Russians have "domes" where the accuracy of GPS-based weapons is drastically reduced. In such conditions, Ukrainians are left with weapons that can operate in that environment, like AASM Hammer bombs or eliminating jammers.

In the second case, Ukrainians can hunt them with drones resistant to jammers, which include, among others, Polish FlyEye cooperating with artillery or special units operating behind Russian lines.

In the meantime, Americans propose a third method, namely the application of additional guidance heads to standard bombs or missile projectiles, which, once launched over a specified area of jammer activity, can target it themselves. Jammers must operate continuously to be effective. Thus, they are vulnerable to being hit by this new weapon, and only their constant protection, e.g., by Pantsir-S1 systems, can provide them with a chance for further activity.

As reported by The Warzone, Americans experimented with such a module for the GBU-39/B Small Diameter Bombs (SDB) in 2020, where the used bombs included an additional guidance module weighing about 1.9 kg.

Since the GLSDB missiles are essentially an SDB bomb mounted on a rocket engine, the creation of an anti-jamming variant in the short term is very likely. Similarly, adding such capabilities to JDAM/ER bombs should not be very difficult either.