Note: All specifications are from recent Jane's Information Group publications (Strategic Weapon Systems, Fighting Ships, Naval Weapon Systems, and All the World's Aircraft), except "Throw-weight", and "Yield" which are from the International Institute for Strategic Studies' Military Balance 1995-6, "Locations," and "Number Deployed" are from Arkin and Norris, Bulletin of the Atomic Scientists. Disagreements are footnoted (with hypertext links), as are selected facts in the text.

The entries are listed as follows:

• Sea-Based Strategic Weapons
• Vanguard SSBN
• Trident II D-5 SLBM (British)
• Air-Based Strategic Weapons
• Tornado GR.1/1A
• WE 177 A/B gravity bomb
• Footnotes
• Link to Brief Summary of United Kingdom Arsenal

Vanguard SSBN

• Year Deployed: 1993
• Displacement: 15,900 tons dived¹
• Dimensions: 149.9 meters length, 12.8 meters beam, 12 meters draft
• Propulsion: Nuclear PWR-2 reactor, 1 shaft, pump jet propulsor
• Speed: 25 knots dived
• Missiles: 16 Trident II D-5 SLBMs
• Locations: Faslane Scotland - 4
• Number Deployed: 4 submarines: HMS Vanguard, HMS Victorious, HMS Vigilant, HMS Vengeance
• Primary Contractor: Vickers Shipyard and Engineering Ltd.

The four Vanguard class ballistic missile submarines (SSBNs) will soon carry the sole deterrent force of the United Kingdom. The U.K. eliminated its last land-based nuclear missiles in 1963, and has decided to eliminate its air-based weapons by 1998, leaving only the nuclear armed Vanguard SSBNs.

The Vanguards replace the Resolution class missile submarines, which were commissioned from 1966-9 -- the last of which was decommissioned in 1996. While all four submarines were in service, they maintained an impressive 54% at-sea availability rate. The Resolution class carried modified Polaris A-3 SLBMs. The costly system, designated the A-3TK Chevaline, had British penetration aids and reentry vehicles designed to defeat the limited Soviet anti-ballistic missile (ABM) system around Moscow.²

When looking for a replacement for the Polaris, the U.K. initially wanted to use the Trident C-4 missile, but in 1983 decided to seek the more advanced Trident II D-5. This decision was not only based on the D-5's increased capacity, but also to ensure commonality with the Americans for easier (and cheaper) production and mainenance. The British wanted to avoid the cost associated with the independent Chevaline system and instead use the most current American system, with the only change being British warheads. The leap in capability from early (albeit modifed) Polaris missiles to the Trident II D-5 is considerable -- it has been described as the "Rolls-Royce" of SLBMs.³

Two of the Vanguards have been deployed, with the third scheduled for commissioning in April 1997 and the fourth in March 1999. The Labour government campaigned to cancel the fourth Vanguard in the April 1992 General Elections, but was defeated. The Vanguard design is based on the Trafalgar attack submarine, complete with anechoic coating for improved quieting. The Vanguard has twice the displacement of its predessesor, but a slightly smaller crew, at 132 compared to 149. Like the United States, Britain maintains two crews (called "Port" and "Starboard") for each missile boat.³

The homeport of the Vanguards will be Faslane, on the shore of Gare Loch (Strathclyde, Scotland). The Vanguards are planned to remain in the strategic role until at least 2020.⁴

Trident II D-5 SLBM (UGM-133A) (British)

• Year Deployed (U.K.): 1995
• Dimensions: 13.42 meters length, 2.11 meters diameter⁵
• Weight: 59,090 kilograms⁶
• Propulsion: Three stage solid-fuel
• Throw-weight: 2,800 kilograms
• Range: 12,000 kilometers⁷
• Guidance: Stellar-aided inertial
• Circular Error Probable: 90 meters
• Warhead: 4-6 warheads likely, probably only four, some sub-strategic with 1 warhead (could theorteically carry 14-16 RVs), warhead thought similiar to U.S. W-76, deployed on U.S. Mark 4 bus⁸
• Yield: estimated 100 kilotons⁹
• Locations: 2 Vanguard class Trident SSBNs
• Number Deployed: 32 missiles
• Primary Contractor: Lockheed Missiles and Space Co.

This highly accurate missile was first deployed for the U.S. on its Ohio class SSBNs in 1989. The D-5 is the first SLBM to have a credible hard target kill capability, contradicting the traditional notion that the sea leg's weapons are inaccurate. Though the British version will not be as potent in this role with a 100 kiloton warhead as the 400 U.S. warheads equipped with the 475 kiloton W-88 warhead, its accuracy still provides a credible hard target destruction capability, a first for British ballistic missiles.

The U.K. D-5 missiles will be identical to those used by the U.S. -- there will be a communal pool of D-5s at the Trident submarine base at King's Bay, Georgia, with about 70 missiles allocated to Britain. Upon commission, British submarines will load their missiles at King's Bay, then sail to Britain's Royal Naval Armament Depot (RNAD) at Coulport to load the warheads. This high level of nuclear cooperation is indicative of the enduring "special relationship" between the U.S. and U.K.¹¹

Though the British Ministry of Defense has stated that the warheads are of British design, it appears that they are very close copies of the American W76 warhead, with much of the design shared and duplicated. Official British statements confirm that most of the warhead costs were "incurred in the U.S." This sharing of information and perhaps design information has been a hallmark of the U.S.-UK special nuclear relationship, although the procedures have recently been challanged as being contrary to the spirit of the Nuclear-Nonproliferation Treaty (NPT). Article I of the NPT forbids transfer of nuclear weapons to "any recipient whatsoever." However, in practical terms, these allegations have not resonated with either the public or policymakers.¹²

The U.K. has announced that it will not outfit its D-5's to their full capability (the U.S. currently loads 8 warheads per missile, and the missile is capable of carrying 12 MIRVs.) In fact, the Ministry of Defense has announced that no more than 96 warheads will be carried on each patrolling submarine. This corresponds to a maximum loading of 6 warheads per missile. There is additional capacity in the D-5 system should the world strategic climate change. Britain could conceivably upload the missiles to the current American standard of eight warheads on each missile, for 128 warheads per boat, but at the moment, it is more likely to deploy only 48-64, for three or four MIRVs per missile. Given the elimination of British air-delivered tactical nuclear weapons, some D-5s will carry only 1 warhead to assume the sub-strategic role. Lower yields for tactical missions could be achieved by using only the first fission stage of the weapon..¹⁰

The British will likely procure three boat loads of warheads, the same as was done for the four boat Poseidon force. Assuming a "standard" 10% for spares and five warheads per missile, that would make for an eventual British nuclear arsenal of about 275 warheads.

Tornado GR.1/1A

• Year Deployed: 1982
• Dimensions: 16.72 meters length, 5.95 meters height, 13.91 meters wingspan (fully spread), 8.60 meters wingspan (fully swept)
• Weight: Empty - 14,091 kilograms, Maximum takeoff - 28,000+ kilograms¹³
• Propulsion: Two Turbo-Union RB199-34R turbofans
• Maximum Speed: Mach 2.2¹⁴
• Range: 1,390 kilometers (hi-lo-lo-hi flight profile)
• Weapon Load: 9,000+ kilograms¹⁵
• Maximum Loadout: 2 WE 177 A/B nuclear gravity bombs, two 27 millimeter cannons, also wide range of conventional air-to-air and air-to-ground munitions
• Locations: (Nuclear-capable squadrons), RAF Marham - ~26, RAF Lossiemouth - ~26, RAF Bruggen (Germany) - ~52
• Number Deployed: (Nuclear capable) 96
• Primary Contractor: Panavia

The Tornado is a twin-engine, two-seater, all-weather fighter-bomber jointly designed and produced for the United Kingdom, Germany, and Italy. The Tornado was designed with a truly multirole airframe capable of close air support/battlefield interdiction, interdiction/counter air strike, air superiority, interception/air defense, naval strike, and reconaisance. Design was completed in 1972, however, the first British version did not become operational until 1982.¹⁶

The Tornado is the descendant of the larger V bombers (Valient, Victor, and Vulcan) which were produced in the 1950s. The last of these in the nuclear role, the Vulcan, retired in 1982, with the Tornado assuming its nuclear delivery role. The first Tornados modified to carry nuclear weapons were based in Germany in 1984. Each Tornado GR.1/1A could carry two WE 117 A/B nuclear bombs. Today there are four nuclear-capable squadrons.

The British GR.1/1A ground attack version, the variant which the nuclear bombs are allocated to, is optomized for low level attacks. The GR.1A is actually a tactical reconnaisance variant, but retains the ability to carry nucear weapons. The ADV (air defense variant) which includes the ADV.2 and ADV.3 is not nuclear-capable.

A mid-life upgrade is ongoing in the Tornado GR.1 fleet, installing improved electronic warfare equipment, better low-level navigation aids, and improved computers, among others. The first improved Tornados, which will be redesignated GR.4, were sheduled for completion by the end of 1996, with upgrades continuing through 1997. These enhancements are designed to keep the Tornado flying well into the 21st century.¹⁷

WE177A/B Gravity Bomb

• Year Deployed: 1966¹⁸
• Dimensions: Unknown
• Weight: A variant - 272 kilograms, B variant - 431 kilograms¹⁹
• Circular Error Probable: Unknown
• Yield: variable (10 kiloton low setting, WE 177 A - 200 kiloton maximum, WE 177 B - 400 kiloton maximum)
• Locations: Assumed deployed at nuclear-capable Tornado airbases, RAF Marham, RAF Lossiemouth, and RAF Bruggen (Germany)
• Number Deployed: 100 weapons
• Primary Contractor: Multiple

The WE 177 is Britain's nuclear gravity bomb. It entered service in 1966, replacing the Red Beard tactical bomb, and the Yellow Sun strategic bomb. There were appromixmately 25 bombs of the C variant of the WE 177, which could be used for maritime strikes or as an air-delivered depth charge, but all were retired in mid-1992. Like the U.S. and Russia, who had removed their tactical nuclear weapons from ships in late 1991, Britain followed suit, also announcing that it would destroy all naval tactical nuclear weapons.

The design lineage of the WE 177 is unclear. It seems most likelt that it is a derivative of the U.S. B57 and B61 bombs, though other sources state it is entirly of British manufacture (however, with only four bomb tests in the design period betweeen 1962 and 1965, this is unlikely.) The A variant is likely based on the low-yield U.S. B-57 fission bomb, while the B variant is likely based on the higher yield U.S. B61 fusion bomb. Most of the WE 177s were built between 1966 and 1982, with an estimated 25 year shelf life. Both variants are parachute retarded for low altitude or laydown delivery (where the bomb parachutes to the ground and detonates after a preset delay in order for the aircraft to escape the blast.)²⁰

In 1991 the RAF announced it would cut its aging WE 177 stockpile in half, and in 1995 it announced it would eliminate them altogether by the end of 1998. There are approximately 100 WE 177 A/B bombs remaining.²¹

¹ Vanuguard displacement is 16,000 tons according to Robert Norris, Andrew Burrows, and Richard Fieldhouse, Nuclear Weapons Databook: British, French, and Chinese Nuclear Weapons (Boulder; Westview Press - National Resources Defense Council, 1994), p. 166.

² Joshua Handler and William Arkin, Nuclear Warships and Naval Nuclear Weapons: A Complete Inventory, Neptune Papers, No. 2 (Washington, DC: Greenpeace and Institute for Policy Stdies, 1988), p. 25.

³ Colin McInnes, Trident: the Only Option? (London: Brasseys Defence Publishers, 1986), p. xi.

⁴ Jane's Fighting Ships 1996-7, (London: Jane's Information Group, 1996), p. 756.

⁵ Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 166.

⁶ D-5 dimentions also listed as 13.6 meters length, 2.18 meters diameter in Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 168.

⁷ D-5 weight also listed as about 57,700 kilograms in Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 168.

⁸ D-5 range is also listed as 11,000 kilometers with reduced payload, 7,400 kilometers with maximum payload of 14-16 RVs (not planned for British D-5's) in Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 169.

⁹ Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 169.

¹⁰ International Institute of Strategic Studies, Military Balance 1995-6 (London: IISS, 1995), p. 288.

¹¹ IISS, Military Balance 1996-7, p. 72 and Arkin and Norrics, "Nuclear Notebook" Bulletin of the Atomic Scientists (November 1996), p. 64.

¹² Arkin and Norris, "Nuclear Notebook" Bulletin of the Atomic Scientists (November 1996), p. 64.

¹³ British-American Security Information Council, The U.K. Trident Program: Secrecy and Dependence in the 1990s (Washington, DC: BASIC, September 1993), p. 33.

¹⁴ Tornado weight empty listed as 12,700 kilograms and maximum as 27,273 kilograms in Norris, Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 157.

¹⁵ Mach 2.2 figure for Tornado speed is clean configuration at altitude, both Jane's and IISS list Mach .92 as level speed with external stores (which would include nuclear weapons), IISS, Military Balance, 1995-6, p. 289, listed as Mach 1.1 maximum speed at sea level in Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 158.

¹⁶ Tornado maximum payload listed as only 6800 kilograms as opposed to 9,000+ in IISS, Military Balance, 1995-6, p.289.

¹⁷ Jane's All the World's Aircraft 1990-1 (United Kingdom, Jane's Information Group, 1990), p. 138.

¹⁸ Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 159.

¹⁹ Information not listed in Jane's, no WE-177 entry. Specifications from Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 129.

²⁰ Information not listed in Jane's, no WE-177 entry. Specifications from Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, p. 129.

²¹ Norris, Burrows, and Fieldhouse, British, French, and Chinese Nuclear Weapons, pp. 60, 129.

²² David Fairhall, "RAF's Stock of Nuclear Bombs Will Be Withdrawn by 1998." The Guardian, 5 April 1995.