View source for WE.177

{{Use dmy dates|date=May 2017}}{{Use British English|date=May 2017}}
{{Infobox weapon
|name           = WE.177
|image          = File:WE177 training nuclear bomb at Explosion Museum.jpg
|image_size     = 300px
|alt            = A mostly green coloured bomb around 3 metres long, marked with the word "training" and with 4 fins at the rear
|caption        = WE.177 nuclear bomb (training example) at [[Explosion Museum of Naval Firepower]]
|origin         = United Kingdom<ref name=SotonGlossary/>
|type           = [[Free fall|Free-fall]] [[gravity]] [[Nuclear weapon|nuclear]] [[bomb]]
|is_explosive   = y
|is_UK          = y
|service        = September 1966–1998<ref name=SotonGlossary/><ref name=AWE/><ref name=CDI.org-UKnukes/>
|used_by        = [[Royal Navy]] and [[Royal Air Force]]
|wars           = [[Cold War]]
<!-- Production history -->
|designer       = [[Atomic Weapons Research Establishment]] (AWRE), [[Aldermaston]]<ref name=AWE/>
|design_date    = 
|manufacturer   = [[Atomic Weapons Research Establishment]] (AWRE), [[Aldermaston]]<ref name=AWE/>
|unit_cost      = unknown
|production_date= 
|number         = ~319
|variants       = WE.177A, WE.177B, WE.177C
<!-- General specifications -->
|spec_label     = 
|weight         = '''WE.177A''': {{convert|272|kg|0|lk=on}},<ref name=SotonGlossary/><ref name=CDI.org-UKnukes/><br>'''WE.177B''' and '''WE.177C''': {{convert|457|kg|-1}},<ref name=SotonGlossary/>
|length         = '''WE.177A''': {{convert|112|in|cm|0|lk=on}},<ref name=SotonGlossary/><br>'''WE.177B''' and '''WE.177C''': {{convert|133|in|cm|0}},<ref name=SotonGlossary/>
|part_length    = <!--{{convert|123|cm|in|0}}-->
|width          = 
|height         = 
|diameter       = {{convert|16|in|cm|0}},<ref name=SotonGlossary/>
<!-- Explosive specifications --> 
|filling        = '''WE.177A''': ZA297 primary fission warhead<ref name=SotonGlossary/><br>'''WE.177B''': ZA297 primary fission warhead & PT176 secondary thermonuclear fusion warhead<ref name=SotonGlossary/><br>'''WE.177C''': ZA297 primary fission warhead & PT176 secondary thermonuclear fusion warhead<ref name=SotonGlossary/>
|filling_weight = unknown
|detonation     = 
|yield          = '''WE.177A''': 0.5&nbsp;[[TNT equivalent|kilotons]] or 10&nbsp;kilotons<ref name=SotonGlossary/><br>'''WE.177B''': 450&nbsp;kilotons<ref name=SotonGlossary/><br>'''WE.177C''': 200&nbsp;kilotons<ref name=SotonGlossary/>
|launch_platform=  '''WE.177A''': [[fixed-wing aircraft]], [[helicopter]], [[Ikara (missile)|Ikara missile]]<br>'''WE.177B''': fixed-wing aircraft<br>'''WE.177C''': fixed-wing aircraft
}}
{{Nuclear weapons}}

The '''WE.177''', originally styled as '''WE 177''',<ref name=SotonGlossary/><ref name=AWE/> and sometimes simply as '''WE177''',<ref name=CDI.org-UKnukes/><ref name=OpCORPORATE/> was a series of [[tactical nuclear weapon|tactical]] and [[Strategic nuclear weapon|strategic]] [[nuclear weapon]]s with which the [[Royal Navy]] (RN) and the [[Royal Air Force]] (RAF) were equipped. It was the primary air-dropped nuclear weapon in the [[United Kingdom]] from the late 1960s into the 1990s.

The underlying design was based on the US [[W59]], which the UK had gained as part of their involvement in the [[GAM-87 Skybolt]] program. The RAF was not happy with the [[Nuclear weapons design|primary stage]] of the W59, which was potentially subject to accidental detonation when subject to mechanical shocks. [[Air Ministry]] [[Operational Requirement]] OR.1177<ref name=SotonGlossary/> was issued for a new design using a less sensitive explosive, which was undertaken at the [[Atomic Weapons Research Establishment]] as "Cleo". When Skybolt was cancelled, the UK gained access to the [[UGM-27 Polaris]] missile and its [[W58]] warhead, but they continued development of Cleo as a tactical weapon to replace [[Red Beard (nuclear weapon)|Red Beard]]. A later requirement for a much smaller tactical and anti-submarine weapon for Navy use was filled by using the new primary as a [[boosted fission weapon]].

Three versions were produced, A, B and C. The first to be produced was the {{convert|450|ktTNT|lk=in}} WE.177B, which entered service with the RAF at [[RAF Cottesmore]] in September 1966. Further deliveries were delayed by the need to complete the warheads for the Polaris A3T. The Navy did not begin to receive its ~10&nbsp;kt (42 TJ) WE.177As until 1969. The 190&nbsp;kt (800 TJ) C models for the RAF followed.

All versions could be delivered by [[fixed-wing aircraft]] and could be [[parachute]] retarded. The WE.177A, in [[anti-submarine]] mode, could also be carried by [[helicopter]]s.

The Navy weapons were retired by 1992, and all other weapons with the RAF were retired by 1998. When it was finally withdrawn in 1998, the WE.177 had been in service longer than any other British nuclear weapon. The WE.177 was the last [[Nuclear weapon|nuclear]] [[bomb]] in service with the Royal Air Force, and the last tactical nuclear weapon deployed by the UK.

==History==
In May 1960, Prime Minister [[Harold Macmillan]] signed an agreement with [[Dwight D. Eisenhower|President Eisenhower]] to purchase 144 [[GAM-87 Skybolt|AGM-48 Skybolt]] missiles for the UKs [[V bomber]] force.  Along with the missiles, the UK would receive the design of the Skybolt's [[W59]] warhead, which was much smaller and lighter than even the smallest UK designs of the era.  The UK version would be known by the codename RE.179.

The W59 primary (fission elements) used a [[polymer-bonded explosive]] codenamed PBX-9404. The British considered this to be unsafe, due to the potential for mechanical shocks to set off the PBX. Since the late 1950s, they had been working on their own primary design, originally 'Octopus', and then 'Super Octopus', that used more explosive and less [[fissile material]], and was shock-insensitive as well.  They proposed adapting the Super Octopus design for use in RE.179, calling the new version 'Cleo'.  Cleo designs were tested underground at the [[Nevada Test Site]] in 1962.<ref name=AWE/> The secondary (fusion elements) of RE.179 remained identical to the W59's, and were known as 'Simon' in WE.177B, and as 'Reggie' in the ET.317 version for [[UGM-27 Polaris|UK Polaris]].

At the time, the UK's only [[tactical nuclear weapon]] was [[Red Beard (nuclear weapon)|Red Beard]], a relatively large weapon of {{convert|2000|lb|-2|lk=on}} weight.  While work continued on Cleo, it was decided to adapt it as a weapon of its own to replace Red Beard,<ref name=CDI.org-UKnukes/> as the 'Improved Kiloton Weapon'.  The adapted version of the primary, now the only part of the physics package, became 'Katie'.  Katie would be used in a new bomb casing to produce WE.177A, replacing Red Beard with a weapon of roughly 1/3 the weight, and much smaller size.  WE.177A would also be used by the [[Royal Navy]], both for surface attack, as well as a [[nuclear depth bomb]],<ref name=OpCORPORATE/> or NDB.

When [[GAM-87 Skybolt|AGM-48 Skybolt]] was cancelled, part of the resulting [[Nassau Agreement]] was the replacement of Skybolt with the [[UGM-27 Polaris|Polaris missile]].  Polaris A3T used its own warhead design, [[W58]].  The W58 was also rejected by the British because it also used PBX-9404 in its primary.  The UK solution was to adapt their RE.179 for the UK Polaris, and assigned the codename ET.317.  The need for ET.317 warheads for UK Polaris was urgent, and development of the Improved Kiloton Bomb was temporarily halted until the Polaris warhead programme was completed.

To fill the gap until Polaris entered service, it was necessary to provide RAF [[strategic bomber]]s with a suitable weapon that would allow them to penetrate [[Warsaw Pact]] defences at low-level, minimising attrition from [[Anti-aircraft warfare|air defences]].  WE.177 was adapted to produce a high-yield interim strategic weapon for the five-year period, while the Polaris submarine force was building.  Halting work on the original WE.177, now known as the 'A' model, a new version that used the [[W59]] secondary, codenamed Simon, matched with a modified 'Katie B' primary created WE.177B.  This version required a lengthened bomb casing, and was somewhat longer and heavier than WE.177A.

[[File:WE.177A sectioned operational round at Old Sarum-3646px.JPG|thumb|Rare WE.177A sectioned<ref name=NWI-photo2/> instructional example of an operational round, one of only two in existence, seen here at Boscombe Down Aviation Collection.<ref name=Boscombe/>]]

During the [[Chevaline]] program, the number of warheads on each Polaris missile was reduced from three to two.  These now-redundant third warheads were adapted into the new WE.177C.  This conversion consisted of removing the original primary, and replacing them with Katie A from the WE.177As.  The new [[warhead]] was placed in existing WE.177B casings, and then [[ballast]]ed to have identical weight and ballistics as the WE.177B.

==Deployment and usage==
[[File:We177 science museum.jpg|thumb|A WE.177B or C training round for ground instructional purposes.  Externally identical to operational rounds, but manufactured in [[steel]] rather than [[aluminium alloy]], and [[Inert munition|inert]]; i.e., does not contain any [[fissile material]]s, explosives, or other hazardous components. The red canister contains the cable required to connect the weapon to the aircraft systems.  The white 'X's cover cartridge-operated ejection ports, and signify that as an inert round, explosive charges are not installed.  'Live' WE.177 bombs had a two inch wide orange band around the circumference of the nose.<ref name=Nuclear-Weapons.info-photo/>]]

Type A, B and C weapons were carried by strike aircraft, including the [[Avro Vulcan]],<ref name=AWE/> [[de Havilland Sea Vixen]], [[Blackburn Buccaneer]],<ref name=AWE/> [[SEPECAT Jaguar]],<ref name=AWE/> and [[Panavia Tornado]].<ref name=AWE/><ref name=CDI.org-UKnukes/>  The [[British Aerospace Sea Harrier|Royal Navy Sea Harrier]]<ref name=AWE/><ref name=OpCORPORATE/> carried only WE.177A, slung beneath the [[starboard]] wing.  The B and C models were too large for this aircraft.  At one time, eight Tornado [[List of Royal Air Force aircraft squadrons|squadrons]] were nuclear capable.

Three paint schemes are known to have been used on WE.177; overall white with red and yellow bands (early paint scheme from the 1960s),<ref name=CDI.org-photo/> and overall green with red details<ref name=AWE/><ref name=Nuclear-Weapons.info-photo/> (later paint scheme from the mid-1970s onwards).<ref name=Skomer/>  The drill weapon used for loading and flight drills was Oxford blue. This was so that a live round could easily be identified, but service procedures required all training rounds to be treated and handled as if they were live. The training rounds even returned the correct indications to the carrying aircraft systems if they were 'armed' in flight. Most of the examples of WE.177 training rounds in museums have been re-painted in green, presumably to look like the original live rounds — an example re-painted green is located on the ground underneath the port wing of the Tornado at the [[Midland Air Museum]].

As with all British [[thermonuclear weapon]]s, the [[tritium]] gas used in the bomb core was purchased from the United States as part of the [[1958 US–UK Mutual Defence Agreement]]; that permitted the US to obtain UK weapons-grade [[plutonium]], in exchange for [[enriched uranium]], tritium, and other specialised material uneconomical to produce in the UK in the very small quantities required. An industrial plant codenamed ''Candle'' located adjacent to the [[Chapelcross nuclear power station]], near the town of [[Annan, Dumfries and Galloway|Annan]], [[Dumfries and Galloway]], Scotland, was built to recover tritium from time-expired service weapons returned for routine maintenance or servicing. It was then recycled after removal of tritium decay products. All boosted fission weapons use tritium, which decays with time, reducing the designed fission yield by approx 4.4% per year.  Reduction in the fission yield of a primary will reduce the thermonuclear [[Nuclear weapon yield|nuclear yield]] by a similar proportion, or even lead to the [[thermonuclear fusion]] stage failing to ignite (known as a "[[Fizzle (nuclear explosion)|fizzle]]"). To maintain optimum yield, all versions of WE.177 required routine maintenance about every three years.  
Normal servicing was carried out by specialist teams of RAF Armourers.

[[File:WE.177 safety keys.jpg|thumb|WE.177 safety and arming keys.  The large white plastic part is the tool used to remove the protective cover from the lock.]]

Part of the safety and arming system on the WE.177 series was a simple key-operated Strike Enable Facility; using a cylindrical barrel key similar to those used on vending or gaming machines.  By agreement with the owners of the lock's design rights, the key profile for each and every live weapon was unique, and would not be used for any other purpose.  The profile for the training rounds was also not used elsewhere, but all training rounds used the same profile.  The physical safety characteristics of WE.177 were probably comparable to similar US weapons, e.g. using the concept of being 'one-point-safe'. The safety and arming system was more sophisticated than on a conventional shell or bomb.  The WE.177 safety and arming system had ''three'' safety breaks (which varied according to delivery mode) in the arming chain, whereas a conventional weapon only requires two.

The casing of WE.177 was unusually robust, and complicated, for a British air-dropped bomb; made necessary by the requirement for the [[laydown delivery]]<ref name=CDI.org-UKnukes/> options.  The stresses from the opening of the drogue parachutes (3 for the A version, 4 for the heavier B/C variants) were particularly severe at the speed anticipated for the [[BAC TSR-2]], the requirement stating a dropping speed of from [[Mach number]] M&nbsp;0.75 to M&nbsp;1.15, at a height of {{convert|50|ft|0}} for TSR-2; and M&nbsp;0.75 to M&nbsp;0.95 for the [[Blackburn Buccaneer]].  This, together with the 'slap down' of the tail on impact required a strong, well-engineered bomb casing to ensure the enclosed warhead remained intact.<ref name="multiref1"/>

Apart from the laydown delivery requirement, the weapon was also required to be used in a '[[Descent (aeronautics)#Dives|dive]] [[Toss bombing|toss]]' mode; from both the TSR-2 (WE.177A/B), and the RAF version of the [[Hawker Siddeley P.1154]] (WE.177A).  This involved releasing the weapon after a dive from {{convert|35000|ft|-3}}, with weapon release at between {{convert|15000|ft|-2}} and {{convert|10000|ft|-2}}, and, for the TSR-2, at speeds from Mach&nbsp;0.80 to Mach&nbsp;2.05.{{citation needed|date=October 2013}}

Intended clearance by 1970 for other types of aircraft and delivery methods included:
{|class=wikitable
|+aircraft and delivery methods
|-
!aircraft!!version!!delivery methods
|-
|[[Handley Page Victor]] Mk.2||WE.177A/B||[[Laydown delivery|laydown]], [[Ballistics|ballistic]], retarded
|-
|[[Avro Vulcan]]<ref name=AWE/>||WE.177A/B||laydown, ballistic, retarded
|-
|[[Vickers Valiant]] Mks: B.1, P.R., K.1., P.R.K.1||WE.177A||laydown, ballistic, retarded
|-
|[[BAC TSR-2]]<ref name=AWE/>||WE.177A/B||laydown, ballistic, retarded, [[wiktionary:loft#Verb|loft]], [[Descent (aeronautics)#Dives|dive]] [[Toss bombing|toss]]
|-
|[[English Electric Canberra]] Mk.B.15 & B.16||WE.177A||laydown, ballistic, retarded, loft
|-
|[[Blackburn Buccaneer]] Mk.2<ref name=AWE/>||WE.177A||laydown, loft, retarded
|-
|[[Sea Vixen]] Mk.2||WE.177A||laydown, loft, retarded
|-
|[[Westland Wasp]]||WE.177A||[[depth charge]]
|-
|[[Westland Lynx]] HAS.1||WE.177A||depth charge
|-
|[[Westland Wessex]] HAS.3||WE.177A||depth charge
|-
|[[Westland Wessex]] HUS||WE.177A||depth charge
|-
|[[Hawker Siddeley Nimrod]]||WE.177A||depth charge
|}
Later, the following aircraft were armed with WE.177:
{|class=wikitable
|+aircraft and delivery methods (later)
|-
!aircraft!!version!!delivery methods
|-
|[[Blackburn Buccaneer]] Mk.2<ref name=AWE/>||WE.177A/B/C||[[Laydown delivery|laydown]], [[wiktionary:loft#Verb|loft]], retarded
|-
|[[Panavia Tornado]] GR.1, GR.1A, GR.4, GR.4A<ref name=AWE/><ref name=CDI.org-UKnukes/>||WE.177A/B/C||loft
|-
|[[SEPECAT Jaguar]]<ref name=AWE/>||WE.177A||laydown, loft, retarded
|-
|[[British Aerospace Sea Harrier|BAe Sea Harrier FRS1]]<ref name=AWE/><ref name=OpCORPORATE/>||WE.177A||laydown, loft, retarded
|}

==Versions==
===WE.177A===
[[File:WE177A-profile png.png|thumb|WE.177A]]
[[File:ASROC-Ikara-LAMPS-MPA.GIF|thumb|The addition of a nuclear option to Ikara. This was never implemented as fitment was cancelled in 1966 before clearance.]]
'''WE.177A''' weighed {{convert|272|kg|0|lk=on}},<ref name=CDI.org-UKnukes/> and had a [[variable yield]] of 10 kt (42 TJ) or 0.5 kt (2 TJ).  It was known to the [[British Armed Forces]] as 'Bomb, Aircraft, HE 600lb MC'.<ref name=OpCORPORATE/>  'MC' (Medium Capacity) referred to a nuclear weapon in the [[kiloton]] range.  The suffix 'HC' (High Capacity) referred to a weapon in the [[TNT equivalent|megaton]] range, although there were some anomalies.

The 0.5&nbsp;kt yield was used only in the [[nuclear depth bomb]] role for detonation above {{convert|130|ft|0}} in shallow coastal waters, or in [[ocean]]ic deep waters to limit damage to nearby shipping.  The full 10&nbsp;kt yield was used below {{convert|130|ft|0}} in deep oceanic waters where no shipping was at risk. The full 10&nbsp;kt yield was also used by [[fixed-wing aircraft]] for surface attack.<ref name=CDI.org-UKnukes/> It had [[air burst]], ground burst or [[laydown delivery]] options.<ref name=CDI.org-UKnukes/>

Although this variant matched the original Improved Kiloton Weapon concept with an added nuclear depth bomb function, and was identified as the A model, it was not the first to be deployed, due to the more pressing needs for the strategic B models.<ref name=AWE/>  At least forty-three were deployed aboard [[Royal Navy]] surface vessels of [[frigate]] size and larger; for use by embarked [[helicopter]]s as an [[anti-submarine]] nuclear depth bomb,<ref name=OpCORPORATE/> starting in 1971.    Helicopter-delivered nuclear depth bombs were not always immediately available, due to fuel-state, other taskings, or expended weapons load.

A further quantity of WE.177As were procured for the [[Fleet Air Arm]]'s (FAA) fixed-wing strike aircraft.  When the Navy's large [[aircraft carrier]]s were decommissioned, around twenty warheads were transferred to the Royal Air Force. The remaining weapons assigned to the Royal Navy were retired in 1992.

The WE.177A was in service not only with the Royal Navy but also on the Royal Air Force bombers and attack aircraft.

===WE.177B===
[[File:WE177B-profile png.png|thumb|WE.177B & C]]
'''WE.177B''' weighed {{convert|457|kg|0}}, with a fixed yield of 450 kt (1900 TJ).  Although it weighed in excess of 1000&nbsp;lb, it was known in RAF Service as the 'Bomb, Aircraft, HE 950lb MC',{{citation needed|date=October 2013}} to differentiate it from the conventional 'Bomb, Aircraft, 1000 lb GP HE', which gave rise to its popular name '950'.  WE.177B had airburst, impact, or laydown options.

Numbers built are still uncertain, but reliable sources put the figure at fifty-three (53), and all were retired by August 1998.<ref name=AWE/>  When Polaris became operational, the Vulcan force continued in a sub-strategic tactical role with these and other bombs assigned to the [[NATO]] [[SACEUR]].  With the retirement of the Vulcans, WE.177B was carried by successor aircraft, including the [[Panavia Tornado]].<ref name=AWE/>

===WE.177C===
'''WE.177C''' weighed {{convert|457|kg|0}}, with a fixed yield of 190 kt (800 TJ).

WE.177C was deployed only in [[RAF Germany]]; in the tactical strike role, and used initially by the [[Sepecat Jaguar|Jaguar]],<ref name=AWE/> and later by the Tornado.<ref name=AWE/><ref name=CDI.org-UKnukes/>  It was deployed probably from the early 1970s, after deployment of [[Chevaline]] had begun.  WE.177C was retired by August 1998.<ref name=AWE/>

{|class=wikitable
!variant!!weight!!length!!estimated yield!!operational<br>(years)!!estimated<br>number
|-
!WE.177A
|{{convert|282|kg|0|abbr=on|lk=on}}<ref name=CDI.org-UKnukes/>||{{convert|112|in|cm|0|abbr=on|lk=on}}||0.5 kt, or 10 kt||1969–1992||~107
|-
!WE.177B
|{{convert|457|kg|0|abbr=on}}||{{convert|133|in|cm|0|abbr=on}}||450 kt||1966–1995||~53
|-
!WE.177C
|{{convert|457|kg|0|abbr=on}}||{{convert|133|in|cm|0|abbr=on}}||200 kt||~1980–1998||~159
|-
!total
| || || || 
!~319
|}

==Further development proposals==
[[File:177 Tie.jpg|thumb|Detail of the official WE.177 project [[Necktie|tie]].  The WE.177 project was denied a project tie for many years, because the project code was, unusually, itself classified.  The symbols represent [[atom]]s: [[hydrogen]], above two atoms of [[nitrogen]]; [[atomic number]]s 1, 7, and 7, respectively.]]

There were several proposals to adapt WE.177A for other delivery systems.  Among them were proposals to re-engineer the WE.177A warhead into two submarine-launched heavyweight torpedoes, which received some attention.  The [[Mark 24 Tigerfish|Mk.24N Tigerfish]] nuclear-armed torpedo had approved project status for some years, but was eventually shelved.  Its raison d'être was to overcome the performance shortcomings of the Tigerfish torpedo, and especially its failure to meet the dive-depth requirements needed to counter deep-diving Soviet SSNs and SSBNs that had outstripped western torpedo performance.<ref name="PRO. DEFE 24/389 E42"/>  There was also a proposal endorsed by Flag Officer Submarines (FOSM), the Royal Navy's professional head of the Submarine Service, to use the WE.177A warhead in another torpedo, the shallow-running unguided [[British 21 inch torpedo#21 inch Mark VIII|Mk.8 torpedo]] of [[World War II]] vintage.<ref name="PRO. DEFE 24/389 E42"/>  A Mk.8 torpedo was chosen to sink the Argentinian warship [[ARA General Belgrano|General Belgrano]], because it was of proven reliability, unlike the unreliable Tigerfish.  This proposal did not gain approved project status, although its raison d'être was similar to that for Tigerfish, and intended to counter extended delays in Tigerfish development.  FOSM's proposal stated that a 10&nbsp;kt nuclear detonation at the Mk.8 torpedo's running depth of approximately {{convert|40|ft|0}} would destroy a deep-diving SSN at {{convert|2000|ft|0}} depth.

The planned M4-Minus version of the [[Ikara (missile)|Ikara]] was also intended to have a nuclear depth charge option as an alternative to its intended payload of a [[Mark 44 torpedo|Mark 44]] or [[Sting Ray torpedo#Design|NAST 7511]] torpedo.  However, this was cancelled in 1966.  The M4-Minus project was apparently cancelled altogether sometime later.

==Falklands War==
{{main|British nuclear weapons and the Falklands War}}
During the [[Cold War]], WE.177A bombs, generally intended for use as [[depth charge]]s (though able to be delivered in any operational mode by the [[Sea Harrier]] FRS1),<ref>Although the Sea Harrier's pilot was able to select both the 'low' and 'high' yield depth charge modes, the aircraft was never cleared for this mode of delivery</ref> were routinely carried on some [[Royal Navy]] warships,<ref name=OpCORPORATE/> and the associated [[Royal Fleet Auxiliary]] (RFA) replenishment ships.  They were kept in containers that were designed to float if they ended up in the sea. In 1982, with the outbreak of the [[Falklands War]], some of these vessels were urgently assigned to the [[Falklands War#British task force|Naval Task Force]], and began to steam south with their nuclear weapons still on board.<ref name=OpCORPORATE/> The [[Ministry of Defence (United Kingdom)|Ministry of Defence]] (MoD) has said that, en route, the bombs were offloaded from escort vessels {{HMS|Broadsword|F88|2}}, {{HMS|Brilliant|F90|2}}, {{HMS|Coventry|D118|2}} and {{HMS|Sheffield|D80|2}}; and were stored in the better-protected deep magazines aboard {{HMS|Hermes|R12|2}} and {{HMS|Invincible|R05|2}}; and the fleet replenishment ships ''[[RFA Fort Austin (A386)|Fort Austin]]'', ''[[RFA Regent (A486)|Regent]]'', ''[[RFA Resource (A480)|Resource]]'', and ''[[RFA Fort Grange (A385)|Fort Grange]]'' who were accompanying the Task Force.  ''Coventry'' and ''Sheffield'' were both later destroyed by enemy action near the [[Falkland Islands]].<ref name=OpCORPORATE/>

The MoD assert that the ships carrying nuclear depth bombs did not enter Falkland Islands territorial waters, or any other areas subject to the [[Treaty of Tlatelolco]]<ref name=OpCORPORATE/> (that established the Latin America Nuclear Weapons Free Zone), to which the UK was a signatory.  The MoD assert that the Task Force [[Commander-in-Chief]] was given instructions on deployment of his forces to avoid any breach of the treaty.<ref name=OpCORPORATE/>  They also state that all the nuclear weapons were returned to the UK aboard the Royal Fleet Auxiliaries ''Fort Austin'' and ''Resource'' on 29 June and 20 July 1982 respectively, after the end of the Falklands War.<ref name=OpCORPORATE/>

==Retirement==
The total number of all versions of WE.177 was between 200 and 250.<ref name=TNAdeclassified/>  All Royal Navy WE.177A weapons were retired in 1992.  WE.177s were planned to remain operational until 2007, however in 1995 the government announced that all WE.177s would be withdrawn by 1998.<ref name=AI>{{cite magazine |date=July 2005 |title=Big Bangs For a Buck |magazine=AIR International |publisher=Key Publishing Ltd.}}</ref> This was achieved by August 1998.<ref name=AWE/> A planned replacement, the standoff Tactical Air-to-Surface Missile (TASM), had been cancelled in October 1993.<ref>{{cite news |last=Bellamy |first=Christopher |date=19 October 1993 |title=Missile system 'no longer needed'; Christopher Bellamy looks at the reasons behind cancellation of the TASM project |url=https://www.independent.co.uk/news/uk/politics/missile-system-no-longer-needed-christopher-bellamy-looks-at-the-reasons-behind-cancellation-of-the-1511708.html |work=The Independent |location=London |access-date=2020-06-14 }}</ref> Shortlisted options for this project were Boeing's [[AGM-69 SRAM|SRAM]], the Lockheed [[AQM-127 SLAT|SLAT]], and Aerospatiale's [[Air-Sol Moyenne Portée|ASMP]].<ref name=AI />

[[Trident missile#Trident II .28D5.29 UGM-133A|Trident D5]] is the [[Nuclear weapons and the United Kingdom|UK's sole remaining nuclear weapons delivery system]] (see {{sclass|Vanguard|submarine|1}}), believed armed with a strategic warhead also usable in the sub-strategic role formerly performed by WE.177.

==Preserved examples==
[[File:We177 science museum.jpg|thumb|WE.177 training round at the [[Science Museum, London|Science Museum]], London]]
[[File:RAF Museum Cosford - DSC08456.JPG|thumb|Two WE.177 training rounds at the [[Royal Air Force Museum Cosford]]]]
[[File:Hack Green Secret Nuclear Bunker objects 05.JPG|thumb|WE.177 training round at [[Hack Green Secret Nuclear Bunker]]]]
Two inert WE.177A operational rounds are on display:
*Boscombe Down Aviation Collection at [[Old Sarum Airfield]] (sectioned);
*Former [[Atomic Weapons Research Establishment]] (AWRE) laboratories at [[Orford Ness]].The body of the item is marked AWRE/6/79 / HGYC and QV 06 79 / REF. No. 76D/00, which literally translates to "Atomic Weapons Research Establishment June 1979 / Hythorn Green Youth Club June 1979 Reference / Judgment No. 76 D00".The paint is white with orange and yellow stripes.

In addition, a number of WE.177 training rounds were donated to museums in the United Kingdom and one in the United States.  Examples are on display at:
*[[Eden Camp Museum]]
*[[Explosion! Museum of Naval Firepower]]
*[[Farnborough Air Sciences Trust]] (two units)
*[[Fleet Air Arm Museum]], [[RNAS Yeovilton (HMS Heron)|RNAS Yeovilton]], [[Somerset]], [[England]]
*[[Hack Green Secret Nuclear Bunker]]
*[[Imperial War Museum Duxford]] (two units)
*[[Imperial War Museum North]]
*[[Midland Air Museum]]
*[[National Atomic Museum]] in [[Albuquerque, New Mexico]], US
*[[North East Land, Sea and Air Museums]] in [[Sunderland]]
*[[RAF Marham]] Aviation Heritage Centre
*[[RAF Regiment]] Heritage Centre at [[RAF Honington]]
*[[Royal Air Force Museum Cosford]] (two units)
*[[Science Museum, London]]
*[[Vulcan Restoration Trust]], [[Southend Airport]]
*[[Yorkshire Air Museum]]
*RAF Museum Laarbruch Weeze, Germany

==See also==
*[[Yellow Sun (nuclear weapon)]]
*[[Nuclear weapons and the United Kingdom]]

==References==
===Citations===
{{Reflist|refs=
<ref name=SotonGlossary>{{cite report|author=Dr Richard Moore|author-link=Richard Moore (academic)|date=March 2004|title=UK Nuclear History, Working Paper, Number: 1; The Real Meaning of the Words: a Pedantic Glossary of British Nuclear Weapons|url=http://nuclear-weapons.info/Working_Paper_No_1.pdf <!-- Dead link:
 http://www.mcis.Soton.ac.uk/Site_Files/pdf/nuclear_history/Working_Paper_No_1.pdf -->|format=pdf|work=[[Mountbatten Centre for International Studies]] (MCIS)|publisher=[[University of Southampton]]}} http://nuclear-weapons.info/Working_Paper_No_1.pdf</ref>

<ref name=AWE>{{cite web|url=http://www.AWE.co.uk/main_site/about_awe/history/timeline/1966/index.html|archive-url=https://web.archive.org/web/20070928010055/http://www.awe.co.uk/main_site/about_awe/history/timeline/1966/index.html|url-status=dead|archive-date=28 September 2007|title=Atomic Weapons Establishment > About AWE > History > WE.177 free-fall bomb enters service|website=AWE.co.uk|publisher=[[Atomic Weapons Establishment]] (AWE)|location=[[Burghfield]]|access-date=26 December 2010|df=dmy-all}}</ref>
<ref name=Nuclear-Weapons.info-photo>{{cite web|url=http://Nuclear-Weapons.info/images/069-storage-container-prep-live-round.png|title=Photograph of RAF Armourers with a live WE.177 (B or C) nuclear bomb, and its associated WE.155 storage and transport container|format=png image|website=Nuclear-Weapons.info|publisher=[[Brian Burnell]]'s guide to British nuclear weapon projects|access-date=22 May 2017}}</ref>
<ref name=CDI.org-UKnukes>{{cite web|url=http://www.CDI.org/issues/nukef&f/database/uknukes.html|title=Nuclear Weapons Database: United Kingdom arsenal|website=CDI.org|publisher=[[Center for Defense Information]] (CDI), [[Washington, D.C.]]|date=2 January 1997|url-status=dead|archive-url=https://web.archive.org/web/20111106201137/http://www.cdi.org/issues/nukef%26f/database/uknukes.html|archive-date=6 November 2011|access-date=28 July 2018|df=dmy-all}}</ref>
<ref name="PRO. DEFE 24/389 E42">[[Public Record Office]] (PRO), London. DEFE 24/389 E 42 Annex Appendix 1, June 1969.</ref>
<ref name=OpCORPORATE>{{cite report|url=http://www.MoD.uk/NR/rdonlyres/4625B8A4-C533-4DAD-9FA5-0BFEE58F8D69/0/op_corporate1982_nuclear_weapons.pdf|title=Operation CORPORATE 1982 - the carriage of nuclear weapons by the Task Group assembled for the Falklands campaign|work=[[CBRN]] Policy|publisher=United Kingdom [[Ministry of Defence (United Kingdom)|Ministry of Defence]]|archive-url=http://webarchive.nationalarchives.gov.uk/20121026065214/http://www.mod.uk/NR/rdonlyres/4625B8A4-C533-4DAD-9FA5-0BFEE58F8D69/0/op_corporate1982_nuclear_weapons.pdf|archive-date=26 October 2012}}</ref>
<ref name=CDI.org-photo>{{cite web|url=http://www.CDI.org/issues/nukef&f/database/we177.jpg|title=Black and white photograph of a live WE.177 nuclear bomb in early white colour scheme, on a trolley|format=jpg image|website=CDI.org|publisher=[[Center for Defense Information]] (CDI), [[Washington, D.C.]]|url-status=dead|archive-url=https://web.archive.org/web/20120214082541/http://www.cdi.org/issues/nukef%26f/database/we177.jpg|archive-date=14 February 2012|access-date=9 February 2016|df=dmy-all}}</ref>
<ref name=Skomer>{{cite web|url=http://www.Skomer.u-net.com/projects/images/we177.jpg|title=Colour photograph of a training version of the WE.177 nuclear bomb, re-painted in hi-gloss green. Original training versions (of all models) were painted blue.|format=jpg image|website=Skomer.u-net.com|publisher=Skomer|url-status=dead|archive-url=https://web.archive.org/web/20120204040609/http://www.skomer.u-net.com/projects/images/we177.jpg|archive-date=4 February 2012}}</ref>
<ref name=NWI-photo2>{{cite web|url=http://Nuclear-Weapons.info/images/we177-sectional-2.png|title=engineering drawing depicting colour-coded two-dimensional sectional views of the WE.177A and WE.177B/C|format=png image|website=Nuclear-Weapons.info|publisher=[[Brian Burnell]]'s guide to British nuclear weapon projects|access-date=22 May 2017}}</ref>
<ref name=Boscombe>{{cite web|url=http://BoscombeDownAviationCollection.co.uk/index_files/Page289.htm|title=Exhibits|website=BoscombeDownAviationCollection.co.uk|publisher=[[Boscombe Down Aviation Collection]] — [[Old Sarum Airfield]], [[Salisbury]]}}</ref>
<ref name="multiref1">[[Public Record Office]] (PRO), London. TNA AIR 2/17328 E3A p1</ref>
<ref name=TNAdeclassified>Various declassified files available at [[The National Archives (United Kingdom)|The National Archives]] (TNA), [[Kew]], London.</ref>
}}

==Bibliography==
* Leitch, Andy. "V-Force Arsenal: Weapons for the Valiant, Victor and Vulcan". ''[[Air Enthusiast]]'' No. 107, September/October 2003. pp.&nbsp;52–59. {{ISSN|0143-5450}}

===Further reading===
*{{cite book|author1=Wayne D. Cocroft|author2=Roger J.C. Thomas|editor=P.S. Barnwell|year=2003|title=Cold War : building for nuclear confrontation, 1946-1989|location=[[Swindon]]|publisher=[[English Heritage]]|isbn=1-873592-69-8}} — outdated and accuracy now suspect.
*{{cite web|author=Carey Sublette|author-link=Carey Sublette|title=Britain's Nuclear Weapons; history of the British nuclear arsenal|url=http://NuclearWeaponArchive.org/Uk/UKArsenalDev.html|date=30 April 2002|website=NuclearWeaponArchive.org|publisher=The Nuclear Weapon Archive; A Guide to Nuclear Weapons|access-date=25 May 2017}} — outdated and accuracy now disputed.
*[[Richard Moore (academic)|Dr Richard Moore]]; A Glossary of Nuclear Weapons; 'Prospero' – Journal of the [[British Rocket Oral History Programme]] (BROHP); Spring 2004; a visiting fellow at the [[University of Southampton]].
*[[Dr.John R. Walker]]; A History of the United Kingdom's WE 177 Nuclear Weapons Programme; The British American Security Information Council (BASIC); March 2019.

==External links==
{{commons category}}
*[https://web.archive.org/web/20110927115430/http://www.century20war.co.uk/page11.html Photo of WE177 after sled-testing in December 1965] — at century20war.co.uk
*[http://Nuclear-Weapons.info/vw.htm#WE.177 WE.177] — at Nuclear-Weapons.info, [[Brian Burnell]]'s guide to British nuclear weapon projects
*[https://web.archive.org/web/20141103114601/http://www.skomer.u-net.com/ Skomer.u-net.com]

{{Naval Service (British)}}
{{Royal Air Force}}
{{UKColdWarProjects}}
{{Strategic nuclear weapon systems of the United Kingdom}}
{{Nuclear technology}}
{{Weapons}}

[[Category:Cold War weapons of the United Kingdom]]
[[Category:Nuclear bombs of the United Kingdom]]
[[Category:Tactical nuclear weapons]]
[[Category:Depth charges]]
[[Category:Military equipment introduced in the 1960s]]