Boeing’s GBU-39 Small Diameter Bomb Phase I (SDB-I) is a specially shaped 250-pound bomb. Its thin and pointed shape gives it extra punch against buildings and hardened targets, its pop-out wings give it very good glide range, and its JDAM-like GPS/INS guidance kit gives it precision. Raytheon’s GBU-53 SDB-II bombs added the ability to strike moving targets.
While there have been true stories of “cement bombs” designed to lower collateral damage, “Focused Lethality Munitions” take a higher-tech tack. This Small Diameter Bomb variant changes the bomb’s casing and internal fill, in order to produce more devastating effects within a smaller area. A carbon-fiber bomb body disintegrates instead of fragmenting, which adds explosive force nearby but largely removes shrapnel issues beyond. Inside, metal particles turn the explosive material into short-range projectiles. The result is especially useful in urban areas, in situations where friendly elements are close to the impact zone, and in campaigns fought using contemporary American counter-insurgency doctrine. Publicly-announced orders have included: