JDAM

The Joint Direct Attack Munition, universally known by its acronym JDAM, is an American guidance kit, built chiefly by Boeing, that bolts onto the tail and body of an existing unguided gravity bomb and adds GPS-aided inertial guidance and movable tail fins, converting an ordinary dumb bomb into a precision-guided weapon capable of striking a fixed target accurately in poor weather or at night when laser-guided bombs relying on a clear line of sight could not. Entering United States military service in the late 1990s, the JDAM kit was designed to be relatively inexpensive compared with a dedicated stand-off guided missile, letting air forces upgrade large existing stockpiles of general-purpose bombs rather than replacing them outright, and it saw its first extensive combat use during the 1999 NATO air campaign over Kosovo and Serbia. JDAM-equipped bombs have since become one of the most widely used categories of precision-guided munitions in American and allied air operations, valued for combining GPS-guided accuracy with the lower cost and simpler logistics of converting existing bomb stocks rather than building an entirely new guided weapon.