Paveway IV versus GBU-12

[Simon Cornes]

I’m after some technical assistance on the difference between these two bombs. 
 

From what I can tell the RAF PWIV came in two versions, the original then an updated version with GPS as well as laser quidance. 
 

Reskit do a 1/32 GBU-12 but not PWIV. Is the original PWIV the same as a GBU-12 and when did the enhanced PWIV enter service?

 

Id be grateful for a bit of clarification please!

Thanks

 

[CT7567]

2 hours ago, Simon Cornes said:

I’m after some technical assistance on the difference between these two bombs. 
 

From what I can tell the RAF PWIV came in two versions, the original then an updated version with GPS as well as laser quidance. 
 

Reskit do a 1/32 GBU-12 but not PWIV. Is the original PWIV the same as a GBU-12 and when did the enhanced PWIV enter service?

 

Id be grateful for a bit of clarification please!

Thanks

 

Not an expert on the RAF nomenclature which I know differs somewhat from the labels used in US service (and no guarantee which Resikit may follow), but generally speaking;

 

GBU-12 = Paveway II laser guidance kit on a Mk 82 500 lb bomb

 

GBU-49 or "Enhanced" GBU-12 (sometimes unofficially 'EGBU-12') = Paveway II kit with additional GPS guidance option added, notable for modelers by addition of dual GPS antennae (truncated cylinders) on opposite sides of the nose section, and an external conduit running from nose to tail.

 

 

Paveway IV (not adopted for US service) is similarly a GBU-12/Mk 82 update with dual-guidance GPS or laser and other enhancements. Notable differences from GBU-49/EGBU-12 are the shape and length of the 'conduit' on the nose section, and a new 'saddle' section between the bomb body and pylon:

 

[Julien]

Not sure if this helps but RAF Waepon

 

 

This was displayed by the Dutch AF

 

[Simon Cornes]

So it looks as though the PWIV has the large saddle and the conduit along the side is larger and extends further forward than in the Enhanced US version so that the GPS sensors have to go on the top and bottom of the PWIV but can fit on the side of the Enhanced GBU ? 

 

Julien - That Dutch bomb is different again - much chunkier conduit compared to US GBU-49 and the 'saddle' is not as defined as the one on the RAF PWIV !!
 

Any idea when the RAF started using the PWIV ? Did they ever use the GBU prior to PWIV ? I have an idea that the PWII is also available as a 500lb bomb so I don’t know if the RAF ever used that - I know they used the 1,000 lb version of the PWII.

[Steve McArthur]

GBU-12 has kind of become the generic term for a 500lb LGB with the Paveway style seeker and pop-out fins.  There are really a slew of different weapons that GBU-12 can refer to.  Another thing that made things confused was Raytheon trademarked Paveway^TM. Now both Raytheon and Lockheed Martin market weapons kits that use laser + GPS guidance with Lockheed licensing the name Paveway from Raytheon. Both Raytheon and Lockheed have also produced the basic LGB seeker kits that are functionally identical even if they have detail differences. 

 

Originally the GBU-12 was part of the original Paveway laser guided weapons project during Vietnam.  Paveway II added the popup fins on on the tail where Paveway I used fixed fins and the seeker was modified to make manufacturing cheaper.  The GBU-12 designation gains extra letters at the end to indicate which combination of seeker and fin kit was used for the assembled weapon.  Paveway II all use a common tail kit all the 500 lb weapsons so the designation differences are all in the seaker variants. 

 

GBU-12/B Paveway I LGB with Mk 82 warhead (first operational model)

GBU-12A/B Paveway I with long wing kit

GBU-12B/B -12C/B -12D/B - Paveway II laser only. I'm not sure what the differences are here, (maybe manufacturer?)

GBU-12F/B - Lockheed Dual Mode LGB + GPS marketed as Paveway II Dual Mode Plus. (I'm not sure this is still in production)

GBU-22/B - Paveway III seeker with Mk 82 warhead. 

GBU-49/B - Originally EGBU-12, Raytheon Enhanced Paveway II dual mode LGB + GPS.

Paveway IV - RAF/Saudi only weapon manufactured by Raytheon

 

After JDAM came out there ended up being two parallel developments, one added laser seekers to JDAM and the other adding GPS to Paveway guidance kits.  For a period the Paveway bombs with GPS added were known as EGBU-12 but that has been mostly dropped. Lockheed has a Dual Model LGB (GPS+Laser) that as far as I can tell was only been sold to the US Navy (GBU-12F/B). I think photos with the GPS antennas on the sides of the seeker are this weapon. It appears that it was a limited production run or it was dropped in favor of the GBU-49. It looks like Lockheed has a current production LGB only version marketed as Paveway II Plus   

 

GBU-49 was originally referred to EGBU-12 but looks like it was redesignated GBU-49 for production. This is the bomb with GPS antennas top and bottom of the seeker and the conduit running down the starboard side.  There seemed to be variants with a zig-zag in the side conduit, but I've only seen this in photos of trade show models.  The conduit is to allow the bomb's computer to connect to the aircraft's weapon's system to receive target coordinates before release.  This connection is at the aft end of the aircraft pylon aft of the bomb shackles.  A basic LGB doesn't need this information, so no conduit and just about any plane that can drop a Mk 82 can drop a LGB, but you need a more sophisticated aircraft to talk to GPS guided weapons. 

 

Now for the RAF.

In the 80's and specifically Desert Storm the RAF used a Paveway II kit on a British 1000lb General Purpose bomb. The UK bombs were shorter and  fatter than the equivalent US 1000lb bomb, so it always looked to me like they mated the 2000lb GBU-10 fin kits to the UK 1000 lb.  But I've seen this arrangement in use all the way up to weapons trials for the Eurofighter.  AFAIK the RAF never fitted LGB kits to anything but the 1000lb GP bomb.

 

Paveway IV is unique to UK & Saudi Arabia.  Wikipedia claims 2008 for service entry. Everything about it seems to be unique. Since the UK didn't use the Mk 80 series they purchase full up weapon rounds. For the USA the warheads are purchased in separate buys from the guidance kits. The USA was probably still dropping bombs made during Vietnam over Iraq. Paveway IV uses a Mk 82 shaped warhead, but it's not technically a Mk 82. The explosive is one the RAF specified that the USA does not use and the weapon casing is different to provide better hard target penetration than the standard Mk 82. The conduit is integrated into the hardback that the sway braces press against. 

 

For more of a history:

https://www.designation-systems.net/dusrm/app5/paveway-1.html

https://www.designation-systems.net/dusrm/app5/paveway-2.html

[Simon Cornes]

Wow Steve, that is very comprehensive, thank you!

 

Simon

[Steve McArthur]

2 minutes ago, Simon Cornes said:

Wow Steve, that is very comprehensive, thank you!

 

Simon

A similar question came up a year ago and I fell down a rabbit hole looking into guided weapons history.  

[Simon Cornes]

🤣🤣🤣

[Steve McArthur]

Go look for photos and find more things to fit in the narrative.  It looks like the RAF was using dual mode seekers before Paveway IV. 

 

A Royal Air Force Typhoon takes off for Libya from Gioia del Colle, southern Italy. 25 May 2011

As RAF Typhoon aircraft play a greater part in deliberate targeting operations, where targets are pre-planned, more are carrying four of the 1000lb Enhanced Paveway II bombs. The aircraft's ability to use its Litening III targeting pod to direct the highly accurate bombs means that a single Typhoon can have a devastating effect on Qadhafi regime targets.

 

[Muzz]

Not forgetting the RAF also employed Paveway III (Similar in appearance to the GBU-24 but a different weapon) on the Tornado and Harrier force.

 

I believe the PW IV has always been dual mode, the PW II in RAF service started out life as laser only before the enhanced version was developed.

[Steve McArthur]

On 10/2/2023 at 6:15 PM, Muzz said:

Not forgetting the RAF also employed Paveway III (Similar in appearance to the GBU-24 but a different weapon) on the Tornado and Harrier force.

 

I believe the PW IV has always been dual mode, the PW II in RAF service started out life as laser only before the enhanced version was developed.

Paveway II and Paveway III originally referred to 2nd and 3rd generations of laser guidance seekers that covered a wide range of warheads, seekers and tail kits.  These laser only systems were later "enhanced" with GPS and sometimes completely redesigned while still using  Paveway II and Paveway III names in their marketing.

 

Paveway IV^TM is the name of the specific 500 lb GPS enhanced LGB sold to the RAF and Saudi Arabia.  There are no 1000lb or 2000lb Paveway IVs.

[Slater]

In US service there was originally intended to be a GBU-22 (Paveway III version with a Mk 82 warhead and a BSU-82 AFG plus a WGU-12 GCU). However, at the time it was a case of mating a $50,000 GCU with a $500 warhead, and USAF determined that the expensive GCU's and AFG's were better reserved for Mk 84 and BLU-109 warheads.

 

The basic GBU-12 has changed little over 40+ years. There have been some improvements to the fuzebolt/clamp ring design and newer CCG's and GCU's have been introduced over the decades. The Mk 82 and Paveway IV warheads are quite similar externally, but the PWIV has no nose fuze well or charging well. It is also supposedly made from a better grade of steel than the Mk 82. I note that PWIW warheads are also individually serial numbered. 

 

 

[Selwyn]

I know it looks very  similar but The only thing common between GBU12 and PWIV is the tail unit and bomb lugs. Everything else is different.  The warhead is not even a Mk 82/BLU-111 type.

 

Selwyn

[Slater]

To me, the Mk 82 and PWIV warheads look outwardly similar in overall shape and I believe the PWIV was designed that way to use the standard MXU-650 airfoil group. Even the forward adapters look similar, although there may be minor differences. The guidance fins and wing assembly even have the same orange rectangle marking that says "FOR USE ON MK 82" although I don't know why UK weapons would need that particular marking. Maybe it was cheaper to not put a change in the drawing? I give the PWIV the nod in overall appearance, though. The paint job and markings look carefully applied in contrast to the average Mk 82. 

[Slater]

Part of a soon-to-be-scrapped batch of PWIV parts:

 

[Simon Cornes]

My original query arose because the Trumpeter Harrier GR.7 kit includes GBU-12 bombs and I wondered how that compared to the PWIV. I now know a lot more as a consequence of replies to this thread and looking at photos of the two bombs so the PWIV is quite different in detail compared to the GBU. The most noticeable things to me are the ‘saddle’ on the PWIV, the conduit that only covers the guidance unit and the GPS receivers on the top and bottom of the PWIV compared to the receivers on the sides of the GBU. But that’s quite a lot of differences!

[Slater]

The PWIV's WGU-56 also has airburst antennas integrated into the front of the GCU, but I think those would be pretty much invisible on a model kit version anyway.

Edited October 7, 2023 by Slater

[Selwyn]

17 minutes ago, Slater said:

Part of a soon-to-be-scrapped batch of PWIV parts:

 

The British 1000lb  PW II (UK) used GBU 10 fins and a modified GBU10 tail unit which stll had the GBU10 markings on them,

 

Selwyn

[Slater]

At my depot we've seen the No 120 (?) tails. Always thought that the UK's green looked so much nicer than the US Olive Drab.

[Selwyn]

4 minutes ago, Slater said:

At my depot we've seen the No 120 (?) tails. Always thought that the UK's green looked so much nicer than the US Olive Drab.

 

4 minutes ago, Slater said:

At my depot we've seen the No 120 (?) tails. Always thought that the UK's green looked so much nicer than the US Olive Drab.

The 120 tail was the GBU10 tail (painted OD)  with a slightly  cone shaped adaptor section to fit the UK 1000lb bomb (GBU 10 is iIIRC  18" diameter, the UK 1000lb 16.5" diameter) inside was fitted with  the UK 114 tail unit arming system so you could use British fuzes. The added adaptor bit was painted UK Deep Bronze Green.

 

Selwyn

[Slater]

The RAF personnel that come over for inspections/stock checks are always a pleasant bunch to work with. Although to the untrained American ear, those with Scottish accents can be a challenge

[NealParkes]

Hi. 
You can get a 1/32 PWIV from Jet Passion. 

 

https://www.scalemates.com/kits/jet-passion-32033-paveway-iv-gps-ins-laser-guided-bomb--1504556

 

 

[Simon Cornes]

Thank you Neal, that is pretty much where I started. I’ve also spoken to Reskit because, surprise surprise, they do two versions of GBU-12 but not the PWIV. Hopefully they will do one before to long!

[nigelshipp]

On 10/7/2023 at 8:13 PM, NealParkes said:

Hi. 
You can get a 1/32 PWIV from Jet Passion. 

 

https://www.scalemates.com/kits/jet-passion-32033-paveway-iv-gps-ins-laser-guided-bomb--1504556

 

 

Jet Passion make lovely detailed stuff and  I'm the UK contact for Jet Passion and they're sold via our group Tornado Sig. £13 a pair in 32

Edited October 9, 2023 by nigelshipp
spelling

[Julien]

On 03/10/2023 at 00:15, Muzz said:

Not forgetting the RAF also employed Paveway III (Similar in appearance to the GBU-24 but a different weapon) on the Tornado and Harrier force.

 

I believe the PW IV has always been dual mode, the PW II in RAF service started out life as laser only before the enhanced version was developed.

You can just see a Paveway III in the background here of the PW IV