The RAF describes the 225kg Paveway IV as;
It is integrated with Tornado and Typhoon, and will be integrated with the UK’s F-35B’s
NATO air operations in the Balkan’s during the nineties had shown how existing precision tactics were frustrated by bad weather and deliberate obscurants,a MoD report concluded that only 40% of the weapons dropped by RAF Tornado and Harrier aircraft hit their targets.
Much greater precision and control were needed.
The MoD invited expressions of interest for the new Precision Guided Bomb requirement in 2001. Alenia Marconi Systems (AMS) teamed with Boeing and proposed the JDAM with Diamond Back wing kit, Elbit Systems a development of their Lizard system, Leigh Aerosystems with Long Shot, Raytheon with Paveway and Sagem with their AASM.
The MoD shortlisted Alenia Marconi Systems (by then, MBDA) and Raytheon in 2002.
Raytheon Systems Ltd won the contract in June 2003, beating MBDA which had entered the Boeing JDAM. ISD was planned to be 2007. Paveway IV included a control and guidance system derived from work done by Raytheon for the USAF. In their bid, Raytheon emphasised the commonality advantages with other in-service weapons.
The evolution of Paveway IV from Paveway II is shown below.
Although approval was gained for integration on Harrier, Tornado and Typhoon, funding constraints meant only Harrier integration contracts were let. During the development, the Paveway IV Baseline was improved with laser guidance capability as evolved from Enhanced Paveway II Lot 3.
The Approved Cost at Main Gate was £363 million, to include integration with Harrier GR.9. Agreed manufacture quantities at Main Gate were 2,303.
In Service Definition was;
After the development and assessment phase had completed, Paveway IV entered service with the RAF in 2008, having met all KUR’s
- The Over The Target Requirement (OTR) shall be no greater than that which can be achieved using Mk 82 bombs delivered with 15m Circular Error Probable (CEP).
- The user shall be able to achieve the OTR in all weather.
- The user shall be able to achieve the OTR 24-hours a day
- The user shall be able to programme the weapon with new target coordinates in the air prior to release.
- The user shall be able to deliver PGBs from Tornado GR4/4A, Harrier GR9/9A, and Typhoon.
- The user shall be able to achieve the effect at the target without causing greater damage to collateral objects than would be created by a Mk 82 bomb delivered within a CEP of 15m.
- The user shall be able to employ the weapon from Harrier GR9/9A on embarked operations from an Invincible Class Aircraft Carrier (CVS).
- The weapon shall have a 75% probability of successfully completing a mission at any stage during its life
From then, it was used operationally in Afghanistan by Joint Force Harrier. The video shows the ability to re-target after release
Joint Force Harrier was relieved by RAF Tornado’s in June 2009 and by then, Paveway IV integration had been completed on Tornado.
MBDA and QinetiQ conducted trials of a penetrating warhead in a technology demonstrator contract funded by the UK and France in 2010. Although the airframe was representative of a Storm Shadow/SCALP it was reported the technology may be pulled through onto other programmes.
The design was called the Hard and Deeply Buried Target Next Generation Multiple Warhead System, or HARDBUT.
Operational ELLAMY (Libya) saw multiple uses of Paveway IV from RAF Tornado aircraft.
A further batch of Paveway IV were ordered in 2012, worth £25 million.
By 2013, the UK had dropped over one thousand Paveway IV’s and the previously planned improvement roadmap was beginning to be explored further.
SPEAR Capability 1 described three potential improvements; low collateral damage warhead, penetrating warhead and improvements to the existing laser seeker to allow a wider engagement envelope.
A £2.13 million contract was awarded in 2013 to Thales for an Insensitive Munition booster for the Paveway IV’s Aurora fuze.
In 2014, the MoD confirmed the cost of a single Paveway IV was £70k
The first drop of a Paveway IV by a Typhoon was conducted by 1 (Fighter) Squadron in November 2014 at the Cape Wrath range.
Raytheon announced the first (and long delayed by US objections) export of Paveway IV to Saudi Arabia in 2014. The contract was reported to be approximately £150 million for 2,400 units, in the order of £62k each. The order will sustain production at the Raytheon Glenrothes facility for at least two years.
Soon after, Raytheon announced the 4,000th delivery of Paveway IV to the RAF.
The low collateral programme achieved an important milestone with a trial detonation of the warhead, the improved guidance software for better attacking moving targets was also flight trialled.
In November 2014, RAF Tornado’s were withdrawn from Afghanistan.
The P1Eb Typhoon enhancement package included integration of Paveway IV and other improvements onto Tranche 2 aircraft. This was completed for six wing pylon carriage through the full flight envelope. This work also included requalification for more demanding flight envelopes on the Tornado.
Another replenishment contract was announced in July 2015, this time for £40 million
It was widely reported that this was due to swapping production slots with Saudi Arabia.
In the same month, the MoD awarded three and a half year £27 million contracts to Raytheon to develop, qualify and manufacture a Tactical Penetrator Warhead for the Paveway IV. This will allow a penetrating warhead weapon to be carried internally on the F-35B, an important and extremely valuable capability.
The warhead itself will be produced by Rheinmetall Italia, like the existing Paveway IV warhead.
The F-35 programme confirmed the first release of Paveway IV in September 2015, it will be integrated for both internal and external carriage on the UK’s F-35B fleet.
Paveway IV has seen extensive use in Iraq and Syria in operations against ISIS as part of Operation SHADER, including release from both Tornado and Typhoon where it has emerged as the principle air to ground weapon of the RAF’s manned fighter fleet, used much more frequently than Dual Mode Brimstone.
|Hellfire||GBU-12||Brimstone||Paveway IV||Paveway IV|
These figures were updated in September 2016 with the publication of the Parliamentary Defence Select Committee Report on Operations Against Daesh.
Paveway IV has proven to be an extremely effective, reliable and versatile weapon, development of a number of enhancements continues.
Paveway IV Capabilities
Paveway IV consists of four main components, nose, tail, warhead and a hardback (spine) that connects the three.
The Thales Aurora Multi-Event Hard Target Fuze (MEHTF) assembly is highly capable, and safe. Two seconds before impact it confirms with the guidance system to confirm it is has been released, is on the course and not being jammed. Without this positive confirmation, the fuze will not arm and weapon detonates.
The fuze can air burst (at variable heights), detonate upon impact or after impact. The post impact detonation mode allows the bomb to detonate on the inside of buildings or buried targets, after penetrating the wall for example.
Guidance is a dual mode system that uses both anti-jamming GPS/INS and semi-active laser (SAL). This system is evolved from the RAF’s Enhanced Paveway II bomb. GPS positioning information is provided by the Selective Availability Anti-Spoofing Module (SAASM)
The warhead is the IM compliant 225kg Mk82 from Lockheed Martin, initially manufactured by Societa Esplosivi Industriali (SEI) in Italy, now Rheinmetall Italia. The fill is PBXN-109 and the assembled warhead was extensively tested for IM compliance, including fast cook-off, slow cook-off, bullet and fragmentation impacts.
The low collateral warhead has been tested but the focus now seems to be on the penetrator warhead. Being able to achieve the same penetrative capability as the Enhanced Paveway III in a weapon a quarter of the size would be an impressive improvement. It uses a hardened steel penetrating rod surrounded by a discarding shroud.
In the second production lot, the existing GPS guidance unit was improved. In order for the Paveway IV to better attack moving targets, up to 70mph, a number of software improvements have been progressively implemented with trials completed in 2014. Enhanced anti-GPS jamming capability has also been developed.
A wing was always envisaged as part of the development path of Paveway IV although it does not appear to of a high priority at the minute. One of the original options was a Leigh Aerosystems/Lockheed Martin LongShot wing kit but there are other options available now.
The RAF also has in service the Enhanced Paveway III Dual Mode Laser guided Bomb (BLU-109 penetrating warhead). This is a larger weapon (1,130kg) is used infrequently and combines GPS, inertial and laser guidance. EPW III was recently used by a Tornado GR.4 in the operation against ISIS, the video below shows a pair of them being used against an underground bunker complex
The smaller Enhanced Paveway II, weighing in at 545kg, is also in service although the Paveway IV is to replace it.
Paveway II and Enhanced Paveway II is currently cleared for Tornado and Typhoon
Paveway III Enhanced Paveway III is currently cleared for Tornado only.
The MoD has expressed an interest to integrate Paveway IV on the new Protector RPAS.
The new multi store’s launcher being developed will allow two Paveway IV (or three Brimstone) to be carried per stores pylon. This will allow Typhoon to carry 12 Paveway IV whilst still retaining a full air-air missile load.