Joint Direct Attack Munition ( JDAM)

Joint Direct Attack Munition ( JDAM). It was contracted to Boeing . it  is a guidance device that converts unguided bombs, to  "smart" munitions. JDAM-equipped bombs are guided by an integrated inertial guidance system coupled to a Global Positioning System (GPS) receiver, giving them a published range of up to 15 nautical miles (28 km). JDAM-equipped bombs range from 500 pounds (227 kg) to 2,000 pounds (907 kg).[1] 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. JDAM is a surface to air weapon


  Sourse : Boeing.com



   The 'JDAM''  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.

                                       SPECIFICATIONS

        Length:    (JDAM and warhead) GBU-31 (v) 2/B: 152.7 inches (387.9 centimeters); GBU-31 (v) 4/B: 148.6 inches (377.4 centimeters); GBU-32 (v) 2/B: 119.5 inches (303.5 centimeters); GBU-38/B: 92.64 inches.

        Weight: (JDAM and warhead) GBU-31 (v) 2/B: 2,036 pounds (925.4 kilograms); GBU-31 (v) 4/B: 2,115 pounds (961.4 kilograms); GBU-32 (v) 2/B: 1,013 pounds (460.5 kilograms); GBU-38/B: 590 pounds.

       Maximum range: Up to 15 nautical miles (28 km)

       Wingspan: GBU-31: 25 inches (63.5 centimeters); GBU-32: 19.6 ins. (49.8 centimeters).

GBU  laser seeker

Here are some components of the JDAM

       Accuracy Specified 13 meters; Realized around 7 meters

Guidance is facilitated through a tail control system and a GPS-aided inertial navigation system (INS). The navigation system is initialized by transfer alignment from the aircraft that provides position and velocity vectors from the aircraft systems. Once released from the aircraft, the JDAM autonomously navigates to the designated target coordinates. Target coordinates can be loaded into the aircraft before takeoff, manually altered by the aircrew in flight prior to weapon release, or entered by a datalink from onboard targeting equipment, such as the LITENING II or "Sniper" targeting pods. In its most accurate mode, the JDAM system will provide a minimum weapon accuracy CEP of five meters or less when a GPS signal is available. If the GPS signal is jammed or lost, the JDAM can still achieve a 30-meter CEP or less for free flight times up to 100 seconds.

  

                                       SOURCES: WIKIPEDIA, BOEING.COM