Small Diameter Bomb

The Small Diameter Bomb (SDB) Program is a key Air Force initiative under the Missile Procurement appropriation, focused on the acquisition and sustainment of precision-guided munitions to enhance operational effectiveness across a range of platforms. The primary objective of the SDB program is to provide increased kills per sortie, enabling current and future aircraft to engage multiple targets with precision and reduced collateral damage. The program supports both procurement and integration efforts, ensuring compatibility with a variety of aircraft including the F-15E, F-22A, F-16C/D, F-35A, B-1, A-10, B-52, B-21, MQ-9, and AC-130W/J.

SDB Increment I (GBU-39/B) is the foundational element of the program, designed to address specific warfighter requirements such as multiple kills per pass, adverse weather capability, precision engagement of fixed and stationary targets, and minimized munitions footprint. The SDB I system leverages the BRU-61 carriage, which allows for the release of four bombs per station, increasing the aircraft's payload efficiency. The program also emphasizes reduced susceptibility to countermeasures and supports both standoff and close air support missions. Integration has been completed on several platforms, with ongoing efforts for additional aircraft.

GBU-39A/B Focused Lethality Munition (FLM) is a variant of SDB I, specifically developed to minimize collateral damage. Its carbon fiber warhead case disintegrates upon detonation, reducing fragmentation and the risk to nearby personnel and property. This variant is particularly suited for urban or sensitive environments where precision and low collateral effects are critical. The FLM supports operational flexibility for commanders requiring tailored effects in complex scenarios.

GBU-39B/B Laser SDB introduces a laser-guided capability to the baseline SDB I, allowing for engagement of moving or relocatable targets. This 250-pound class weapon features deployable wings for extended standoff range, a dual-mode seeker (laser and GPS), and a Height-Of-Burst fuze for selectable weapons effects. The Laser SDB enhances the Air Force's ability to conduct dynamic targeting and supports missions requiring rapid response to emerging threats.

BRU-61 Carriage System is integral to the SDB program, providing the interface and release mechanism for the bombs. The system comes in two variants, BRU-61/A and BRU-61B/A, differing in power supply and voltage conversion capabilities to accommodate various aircraft electrical architectures. The carriage system ensures reliable communication between the aircraft and the munitions, supporting mission flexibility and rapid reconfiguration.

Funding for the SDB program in FY 2026 supports the procurement of SDB Increment I weapons, BRU-61 carriage systems, operational flight program updates, production testing, and integration efforts. It also addresses obsolescence and diminishing manufacturing sources through studies, bridge buys, and qualification activities. The program invests in digital acquisition practices, information management, and security infrastructure upgrades to sustain and evolve capabilities. Contractor services, logistics support, and government operational costs are included to ensure program continuity and responsiveness to changing inventory objectives.