The much-anticipated Ground Launched Small Diameter Bomb, or GLSDB, will not arrive in Ukraine until early next year, Reuters reported yesterday. Delays in contracting the system’s production postponed delivery by months. When the GLSDB finally does arrive, however, it will help fill an important gap for Ukraine.
A joint project by Saab and Boeing, development of the GLSDB began years before Russia launched its full-scale invasion of Ukraine. The system marries the GBU-39 Small Diameter Bomb with the M26 rocket motor — both of which are combat-proven, relatively cheap, and abundant in U.S. inventories. This reduces cost and saves time in production.
Reuters first revealed that the Pentagon was considering supplying the GLSDB to Ukraine back in November 2022. At the time, the news agency reported that the system could be delivered as early as the following spring. But the Department of Defense (DoD) did not announce plans to provide the GLSDB to Kyiv until February. Politico then reported that delivery could take up to nine months. A Pentagon official later testified that the GLSDB would “come online this fall.”
In September, however, staffers from the Senate Armed Services Committee told Roll Call that the GLSDB would not be delivered to DoD until December and would then need to be tested. A U.S. Air Force spokesperson said the testing process will be condensed and combined with training for Ukrainian operators.
On Thursday, Reuters confirmed that Boeing, the GLSDB’s prime contractor, plans to deliver the GLSDB to DoD in late December. The system reportedly will then undergo several months of testing before shipment to Ukraine. A Pentagon spokesman said the department then expects to provide the GLDSB to Ukraine “in the early 2024 timeframe after successful verification.” DoD did not sign the contract until March 2023, which further delayed production, Reuters added.
When it eventually reaches the battlefield, the GLSDB will provide Ukraine with a useful long-range precision-strike capability.
At up to 150 kilometers, the GLSDB offers almost double the range of Ukraine’s Western-donated GMLRS rockets, albeit with a smaller warhead. Ukraine can use the GLSDB to strike Russian logistics and command-and-control nodes, airbases, air defense systems, and other high-value targets deep behind the front lines.
The GLSDB is allegedly accurate within 1 meter, using the Small Diameter Bomb’s GPS-aided inertial navigation system for guidance. According to the developers, the GLSDB boasts relatively strong resistance to electronic interference, although Russia has reportedly found some success in jamming GMLRS rockets and guided bombs provided to Ukraine.
The GLSDB is also highly survivable. With integration, it can be launched by Ukraine’s Western-supplied M142 HIMARS and M270 MLRS rocket artillery systems, which Russia has so far proven unable to destroy. It can also be fired by non-traditional launchers, such as from a nondescript shipping container or the back of a pick-up truck.
Perhaps most important, the GLSDB is cost-effective. Ukraine can use the system to strike targets on which it cannot afford to expend Western-donated Storm Shadow, SCALP-EG, or ATACMS missiles, which are far more expensive and in scarce supply.
GLSDB production will take some time to ramp up, however. Initial deliveries will likely be measured in the tens, not the hundreds.
Kyiv would no doubt like to have receive the GLSDB sooner, ideally before its spring-summer counteroffensive petered out. Still, the GLSDB will provide a useful addition to Ukraine’s increasingly diverse arsenal of long-range precision-strike systems.
