The weapon is a guidance kit based on the existing Enhanced Paveway II Enhanced Computer Control Group (ECCG) added to a modified Mk 82 general-purpose bomb with increased penetration performance. The new ECCG contains a Height of Burst (HOB) sensor enabling air burst fusing options, and a SAASM (Selective Availability Anti Spoofing Module) compliant GPS receiver. It can be launched either IMU (Inertial Measurement Unit) only, given sufficiently good Transfer Alignment, or using GPS guidance. Terminal laser guidance is available in either navigation mode.
The Paveway IV entered service with the Royal Air Force in 2008. It has yet to be accepted into service with the United States, which has pursued the development of the Laser-JDAM and dual mode Small-Diameter Bomb (SDB).
The Paveway IV's first export sale was to the Royal Saudi Air Force in a deal worth approximately £150 million (US $247 million). The deal had been delayed for several years by the U.S. State Department which had to authorise the bomb's sale due to its use of American components. A contract was signed in December 2013 with Congressional approval given two months later, with deliveries to begin within 18 months.
The Paveway IV was first used operationally by the Royal Air Force during Operation Herrick in Afghanistan. It was later used operationally during Operation Ellamy in Libya, and Operation Shader in Iraq and Syria. In December 2015, the Royal Air Force began strike operations in Syria as part of Operation Shader, and deployed Paveway IV operationally from its Eurofighter Typhoons for the first time.
Paveway IVs were also used in the Saudi Arabian-led intervention in Yemen. In 2015 for a period export licences were withheld over concern about how they might be used in Yemen, but after some assurances were made exports were resumed. The sales are being investigated by the Committees on Arms Export Controls.
Raytheon UK is conducting preparatory work to equip the Paveway IV with a bunker-busting warhead as part of the Selective Precision Effects At Range (Spear) Capability 1 program. The compact penetrator has the same outer mold line and mass of the regular Paveway IV and uses a discarding shroud design. A penetrating 500 lb Paveway IV would replace the RAF's previous 2,000 lb Paveway III bunker buster. The penetrating version of the Paveway IV will enter service on the Typhoon in early 2019. Raytheon claims the new warhead has the performance of the BLU-109 penetrating bomb, despite being one-quarter of its weight. In December 2016, the Obama administration blocked a transfer of Paveway IV bombs to Saudi Arabia because of concerns about civilian casualties which officials put down to poor targeting.
On 19 June 2015, a Royal Air Force test pilot released two inert Paveway IV laser-guided bombs from a Lockheed Martin F-35 Lightning II during trials in the United States. This marked the first successful firing of a non-US munition during the F-35's development programme. Paveway IV is a future candidate for integration on the aircraft, and will be used operationally by both the Royal Air Force and the Royal Navy when the F-35 enters service with both arms.
Britain is transferring Paveway IV precision guided bombs originally earmarked for the Royal Air Force to Saudi Arabia to enable the Gulf state to build stocks of the weapon being used against targets in Yemen and Syria, sources here said.