Overview
The JDAM is not a stand alone weapon, rather it is a "bolt-on" guidance package that converts unguided gravity bombs into Precision-Guided Munitions, or PGMs. The key components of the system consist of a tail section with aerodynamic control surfaces, a (body) strake kit, and a combined inertial guidance system and GPS guidance control unit. It is typically installed by Naval Aviation Ordnancemen or Air Force Munition Systems Specialists shortly before loading onto the delivery aircraft.
JDAM-equipped bombs range from 500 pounds (230 kg) to 2,000 pounds (910 kg). When installed on a bomb, the JDAM kit is given a GBU (Guided Bomb Unit) nomenclature, superseding the Mark 80 or BLU (Bomb, Live Unit) nomenclature of the bomb to which it is attached.
Read more about this topic: Joint Direct Attack Munition