Jump to content

Ground Launched Small Diameter Bomb

From Alfawiki
Boeing and Saab Group (joint development)
Company typeJoint venture / collaboration
IndustryDefense, Military technology
Founded2023
ProductsGround Launched Small Diameter Bomb (GLSDB)

Ground Launched Small Diameter Bomb

The Ground Launched Small Diameter Bomb (GLSDB) is a munition jointly developed by Boeing and the Saab Group that adapts Boeing's GBU-39 Small Diameter Bomb (SDB)—initially designed for aerial deployment—for launch from terrestrial platforms. This system integrates the SDB with the M26 rocket, allowing it to be fired from ground-based missile launchers such as the M270 Multiple Launch Rocket System and M142 HIMARS.

Production of the GLSDB commenced in 2023, with its inaugural operational use occurring in 2024 during the Russian invasion of Ukraine. However, its effectiveness in combat was reportedly limited due to Russian electromagnetic warfare measures and shortcomings in operational tactics, techniques, and procedures.

Design

Boeing collaborated with Saab to engineer an "inter-stage adapter" that links the Small Diameter Bomb (SDB) to an M26 rocket.[1][2] The Norwegian-Finnish firm Nammo, responsible for the booster rocket, and Norway’s Nordic Shelter, which supplies launchers, also contribute technical expertise.[3][4][5] A significant benefit of utilizing the M26 rocket is the extensive existing inventory. Production of these rockets ended in 2001 after manufacturing 506,718 units.[6] By 2004, the total inventory stood at 439,194 rockets. However, by 2007, efforts were underway to destroy them.[7] The original M26 warhead did not comply with the Convention on Cluster Munitions—which the United States has not ratified.[3]

While capable of launching from MLRS or HIMARS platforms, the GLSDB also features its own launcher that resembles a standard 20-foot (6.1 m) shipping container, enhancing concealment and enabling decoy deployment to complicate enemy targeting.[8][9] Upon launch, the rocket motor propels the bomb to sufficient altitude and velocity before the SDB separates and deploys wings, enabling it to glide toward its target.[1] The GLSDB's warhead carries roughly one-third less explosive material than the existing M31 rocket, varying by type,[10] approximately 16 kg (35 lb) compared to 23 kg (51 lb).Cite error: The opening <ref> tag is malformed or has a bad name[11] Unlike typical MLRS rockets that follow ballistic trajectories, the rocket-launched SDB can ascend to altitude and glide along a programmed flight path.[12][1] MLRS units can fire up to twelve M26 rockets simultaneously, whereas HIMARS launchers accommodate six at once.[13]

In February 2015, Boeing and Saab Group successfully completed three GLSDB test firings. Distinct from traditional artillery systems, GLSDB offers full 360-degree engagement capability at both high and low attack angles. It can maneuver around terrain features to strike targets behind mountains or even reverse course to hit objectives located behind the launch point. Its operational range extends up to 150 km (93 mi), including targets situated as far as 70 km (43 mi) behind the firing position.Cite error: The opening <ref> tag is malformed or has a bad nameCite error: The opening <ref> tag is malformed or has a bad name The weapon system can be configured for airburst detonation or delayed impact for penetrating hardened targets.[2]

During a demonstration in 2017, the GLSDB successfully engaged a moving target at 100 km (62 mi) distance. After separation at altitude, the bomb employed a semi-active laser (SAL) seeker to locate and strike the target.[14] Prior testing validated its capability against targets moving at speeds up to 50 miles per hour (80 km/h).Cite error: The opening <ref> tag is malformed or has a bad name

The precise cost of GLSDB remains undisclosed; however, the SDB component alone costs approximately $40,000 to the U.S. military,[15][16] while the M26 rocket is sourced from obsolete stockpiles. The expenses attributed to the "inter-stage adapter," launcher-container development, and other Boeing and Saab production costs have not been publicly revealed.[17] For context, an individual M31 rocket is estimated around $500,000,[10] though this figure may reflect export pricing rather than U.S. Army procurement costs.[18] According to U.S. Army budgeting data for 2023, each GMLRS round costs approximately $168,000.[19][20] GLSDB is being proposed as a long-range alternative for Ukraine in lieu of 300 km (190 mi) ATACMS missiles,[21][22] which exceed $1 million per unit in estimated cost.[23] Another long-range option includes 250 km (160 mi) Storm Shadow missiles,[24] priced at about £2 million ($2.5 million) each in fiscal year 2023.[25] The United Kingdom has committed to supplying these missiles to Ukraine.[26] The development objective was to provide less affluent nations with precision strike capabilities comparable to those of more technologically advanced air forces.[13]

Unlike conventional artillery rounds that travel along predictable ballistic paths from launch point to impact zone, GLSDB’s winged design and guidance system enable it to navigate around obstacles and evade air defenses by adjusting its flight path—even allowing it to approach targets from behind.[27][1] Additionally, as a gliding munition, it produces a minimal IR signature, diminishing vulnerability to IR homing missiles such as MANPADS.[28]

Use in combat

On 3 February 2023, the United States government revealed a new aid package for Ukraine amid the 2022 Russian invasion of Ukraine. This assistance included the GLSDB, a weapon capable of being launched from existing Ukraine-operated HIMARS or MLRS systems—or alternatively from its dedicated launcher—to strike Russian positions beyond the reach of GMLRS munitions. The GLSDB effectively extends Ukraine’s strike range nearly twofold compared to previous capabilities, reaching up to 150 km (93 mi) versus the 85 km (53 mi) maximum range offered by GMLRS.

The weapon system entered its "initial mass production phase" during 2023. By 30 January 2024, Politico reported that deployment of these missiles could commence as early as the next day. Subsequently, on 14 February 2024, Russian media circulated footage believed to show GLSDB tail remnants discovered near Kreminna, Luhansk Oblast. Later, on 26 March 2024, a GLSDB was utilized to target a residence in Chernyanka, Kherson, identified as a base for Russian UAV operators. Additionally, by February 2025, Ukrainian forces had employed the GLSDB to destroy a Russian 2S9 Nona 120 mm mortar and severely damage another in Zaporizhzhia.

In April 2024, a U.S. defense official commented on the weapon’s battlefield effectiveness as underwhelming. Factors such as Russian electronic jamming and shortcomings in Ukrainian tactics, techniques, and procedures contributed to its limited success. However, it was unclear if this evaluation specifically referred to the GLSDB or possibly other systems like the APKWS II or undisclosed munitions. The Under Secretary of Defense for Acquisition and Sustainment, William LaPlante, acknowledged that the weapon's production and testing were expedited under pressing circumstances and cited multiple challenges including tactical doctrine and electromagnetic interference.

Since November 2023, the Ukrainian Air Force has employed air-dropped GBU-39 Small Diameter Bombs, which have demonstrated resilience against jamming efforts and achieved an accuracy rate approaching 90 percent. In contrast to the ground-launched GLSDB variant—which faced effectiveness issues due to Russian electronic warfare—the air-launched version’s smaller size and launch method make it more difficult to intercept. This compactness allows it to potentially strike targets before Russian jamming can take effect. Notably, the GLSDB follows a "parabolic flight path" similar to artillery fire that can be detected via radar.

By 13 March 2025, amid shortages of ATACMS missiles, the United States resumed supplying Ukraine with GLSDB units featuring enhanced reinforced connections designed to counter electronic jamming. These upgraded munitions are capable of speeds up to Mach 5 and maintain a maximum range of approximately 150 kilometers.

Current users

Prospective users

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 Cite error: Invalid <ref> tag; no text was provided for refs named defensenews
  2. ↑ 2.0 2.1 Cite error: Invalid <ref> tag; no text was provided for refs named Newdick 2022
  3. ↑ 3.0 3.1 Cite error: Invalid <ref> tag; no text was provided for refs named Whitney 2015
  4. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Shephard 2021
  5. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Selinger 2022
  6. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Marine Corps Gazette
  7. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Monitor 2020
  8. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Detsch 2023
  9. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Hardie-Bowmn
  10. ↑ 10.0 10.1 Cite error: Invalid <ref> tag; no text was provided for refs named Korshak 2023
  11. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named General Dynamics Ordnance and Tactical Systems 2021
  12. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named shep
  13. ↑ 13.0 13.1 Cite error: Invalid <ref> tag; no text was provided for refs named Axe 2023
  14. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named areuro
  15. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named reuta
  16. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Trevithick 2020
  17. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Dyson 2019
  18. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Defense Express 2022
  19. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Altman 2022
  20. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Parsons 2022
  21. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Yahoo 062223
  22. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Gould 2023
  23. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Cancian 2022
  24. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named British Pounds to US Dollars Exchange Rate 2023
  25. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Sabbagh 2023
  26. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Reuters 2023
  27. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Chuck Hill's CG Blog 2022
  28. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Bisht 2023
Retrieved from "https://www.alfawiki.org/index.php?title=Ground_Launched_Small_Diameter_Bomb&oldid=76972"