An earlier effort to adapt a Small Diameter Bomb for ground launch involved modifying Boeing’s GBU-39/B with a solid booster, leading to the development of the GLSDB in collaboration with Raytheon and Saab. However, in combat operations over Ukraine, the system was found to be vulnerable to Russian electronic warfare countermeasures.
GBU-53/B brings major guidance upgrades over its predecessor
Unlike its predecessor, the GBU-53/B features a significantly more advanced guidance system. The original GBU-39/B Small Diameter Bomb relies primarily on satellite and inertial navigation, with only a specific subvariant incorporating a semi-active homing system. Since this lightweight bomb depends entirely on precision, electronic warfare disruptions can greatly diminish its effectiveness.