W59

Last updated
W59
Mark 5 warhead.png
The Mark 5 Reentry Vehicle [lower-alpha 1] that housed the W59 warhead
Type Nuclear warhead
Service history
In service1962 to 1969
Used byUnited States
Production history
Designer Los Alamos National Laboratory
Specifications
Mass550 pounds (250 kg)
Length47.8 inches (121 cm)
Width16.3 inches (41 cm)

Detonation
mechanism
Contact, airburst
Blast yield800 kilotonnes of TNT (3,300 TJ)

The W59 was an American thermonuclear warhead used on some Minuteman I ICBM missiles from 1962 to 1969, and planned to be used on the cancelled GAM-87 Skybolt air-launched ballistic missile.

Contents

History

Minuteman application

Development of the Minuteman I ICBM was authorized in February 1958 and by March, the study of possible warhead for the new ICBM was completed. In April, the XW-56 warhead designed by Lawrence Radiation Laboratory (now Lawrence Livermore National Laboratory) was approved for development. This program required considerable effort and was accompanied by funding issues. [1]

Though the intermediate details and dates remain classified, at some point during or before December 1960, a second Minuteman warhead was authorized with a planned first production date of July 1962 and a full scale production date of December 1962. [2] In March 1961, the XW-59 nomenclature was accepted for this warhead. [3]

Firing set components would be off-the-shelf items repackaged for the special shape required for the role. The warhead would contain no electrical power, with an externally powered rotary chopper[ definition needed ] provided to charge the weapon's X-unit. An inertial switch would be provided to prevent weapon arming before it experienced its launch environment. In December 1960, it was decided to use the environmental sensing device (ESD) from the XW-56 in the XW-59. [2]

In January 1961, the Mark 5 reentry vehicle (RV) joint working group, already assigned the task of mating the XW-56 to the Mark 5 were also given the task of fitting the XW-59 to the RV. In May, a second working group for the Mark 11 RV was formed. The plan was to introduce the Mark 11 into service in January 1963 with the eventual replacement of all Mark 5 RVs with Mark 11s. [4]

In May 1961 it was noted that the weapon's RV and fuzing system would be developed by Avco while Sandia National Laboratories would be responsible for the firing set, external initiators, ESD and housing and mounting structures. The warhead would also be compatible with the Skybolt application and that all electrical components, except the external initiators, were already in production. Safety was assured by not having any source of power in the warhead, the use of ESDs, and that two firing signals in the correct order had to be received to detonate the weapon. [5]

Flight tests of the weapon were conducted in late 1961 and the Mark 59 Mod 0 warhead was design released in December 1961. Though the Minuteman missile's operational availability date was pushed from July to September 1962, the warhead's first production date remained unchanged and the first warhead was delivered on schedule in June 1962. [6]

The final development report for the Mark 59 Mod 0 noted that the warhead met all the design specification, with some still classified exceptions. [7]

A total of 150 W59 warheads were produced from June 1962 to July 1963. All warheads were retired by June 1969. [8]

Skybolt application

Search for a suitable warhead for the Skybolt missile began in March 1960. The requirements included a first production date of July 1963 and that the weapon could be made in large numbers. In April 1960 a study group met to determine a suitable design compatible with Skybolt. [9] The operational deployment date was scheduled for July 1963. [10]

During this study group, it was determined that the XW-56-derived ESD used in the XW-59 would be unsuitable for the Skybolt application due to the requirement for free-fall drop delivery option. [11] In March 1961, the Skybolt joint working group met and concluded the initial July 1963 deployment date was unrealistic as flight tests of the weapon had still not been conducted. [12] Further, due to the need for a special ESD, the XW-59 warhead for Skybolt was renamed the XW-59-X1. [13]

As the production date for Skybolt began to slip, first flight tests were scheduled for December 1963. Sandia objected to the planned program of only two flights, wanting eight to twelve test flights instead. In August 1961, first production date for Skybolt was rescheduled to April 1964 at Sandia's request. [14]

In December 1962, all effort on the XW-59-X1 was halted, and in March 1963 the Skybolt program and its warhead were cancelled. [15]

Design

The W59 was 16.3 inches (41 cm) in diameter and 47.8 inches (121 cm) long, and it weighed 550 pounds (250 kg). [8] From official documents, it had a design yield of 800 kilotonnes of TNT (3,300 TJ). [lower-alpha 2] The weapon had both contact and airburst fuzing modes. [17]

The W59 was one of five nuclear weapon designs identified by researcher Chuck Hansen as using the common design Tsetse primary. Hansen's research indicates that the Tsetse primary was used in the US B43 nuclear bomb, W44 nuclear warhead, W50 nuclear warhead, B57 nuclear bomb, and W59. [18]

Historical evidence indicates that these weapons shared a reliability problem, which Hansen attributes to miscalculation of the reaction cross section of tritium in fusion reactions. The weapons were not tested as extensively as some prior models due to the 1958 to 1961 test moratorium, and the reliability problem was discovered and fixed after the moratorium ended. This problem was apparently shared by the Python primary designs. [18]

See also

Notes

  1. Not to be confused with the Mark 5 reentry body (RB) used by the US Navy.
  2. The report states that the 550 lb (250 kg) warhead for Minuteman has a yield of 800 kilotonnes of TNT (3,300 TJ) and the 600 lb (270 kg) warhead had a yield of 1,200 kilotonnes of TNT (5,000 TJ). [16] The W59 is the only 550lb warhead for Minuteman. [8]

Related Research Articles

<span class="mw-page-title-main">GAM-87 Skybolt</span> Air-launched ballistic missile Air-to-surface missile

The Douglas GAM-87 Skybolt was a hypersonic air-launched ballistic missile (ALBM) developed by the United States during the late 1950s. The basic concept was to allow US strategic bombers to launch their weapons from well outside the range of Soviet defenses, as much as 1,000 miles (1,600 km) from their targets. To do this in an air-launched form, a lightweight thermonuclear warhead was needed. Initially, the W47 from the Polaris missile was selected, but it was later replaced by the W59 from the Minuteman missile.

<span class="mw-page-title-main">LGM-30 Minuteman</span> American ICBM, in service

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<span class="mw-page-title-main">Multiple independently targetable reentry vehicle</span> Ballistic missile payload containing multiple warheads which are independently targetable

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Red Snow was a British thermonuclear weapon, based on the US W28 design used in the B28 thermonuclear bomb and AGM-28 Hound Dog missile. The US W28 had yields of 70, 350, 1,100 and 1,450 kilotonnes of TNT and while Red Snow yields are still classified, declassified British documents indicate the existence of "kiloton Red Snow" and "megaton Red Snow" variants of the weapon, suggesting similar yield options, while other sources have suggested a yield of approximately 1 megatonne of TNT (4.2 PJ).

<span class="mw-page-title-main">B53 nuclear bomb</span> American high-yield nuclear gravity bomb

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<span class="mw-page-title-main">B28 nuclear bomb</span> Nuclear bomb

The B28, originally Mark 28, was a thermonuclear bomb carried by U.S. tactical fighter bombers, attack aircraft and bomber aircraft. From 1962 to 1972 under the NATO nuclear weapons sharing program, American B28s also equipped six Europe-based Canadian CF-104 squadrons known as the RCAF Nuclear Strike Force. It was also supplied for delivery by UK-based Royal Air Force Valiant and Canberra aircraft assigned to NATO under the command of SACEUR. In addition, certain U.S. Navy carrier based attack aircraft such as the A3D Skywarrior, A4D Skyhawk, and A3J Vigilante were equipped to carry the B28.

<span class="mw-page-title-main">B41 nuclear bomb</span> American high-yield thermonuclear weapon

The B-41 was a thermonuclear weapon deployed by the United States Strategic Air Command in the early 1960s. It was the most powerful nuclear bomb ever developed by the United States, with a maximum yield of 25 megatons of TNT. A top secret document, states “The US has stockpiled bombs of 9 MT and 23 MT...” which would likely be referring to the B-41's actual yield(s). The B-41 was the only three-stage thermonuclear weapon fielded by the U.S.

<span class="mw-page-title-main">W54</span> Nuclear warhead used by the US

The W54 was a tactical nuclear warhead developed by the United States in the late 1950s. The weapon is notable for being the smallest nuclear weapon in both weight and yield to have entered US service. It was a compact implosion device containing plutonium-239 as its fissile material, and in its various versions and mods it had a yield of 10 to 1,000 tons of TNT.

<span class="mw-page-title-main">Medium Atomic Demolition Munition</span>

Medium Atomic Demolition Munition (MADM) was a tactical nuclear weapon developed by the United States during the Cold War. It was an atomic demolition munition (ADM), a combat engineering device for demolition of structures and for battlefield shaping. The device contained a W45 warhead with an estimated yield of 0.5 to 15 kilotonnes of TNT. Each MADM weighed 391 pounds (177 kg) in its transportation container. They were deployed between 1962 and 1986.

<span class="mw-page-title-main">W78</span> American thermonuclear warhead

The W78 is an American thermonuclear warhead with an estimated yield of 335–350 kilotonnes of TNT (1,400–1,460 TJ), deployed on the LGM-30G Minuteman III intercontinental ballistic missile (ICBM) and housed in the Mark 12A reentry vehicle. Minuteman III initially carried the older W62 warhead with a yield of 170 kilotonnes of TNT (710 TJ), but starting in December 1979 and ending in February 1982, some W62 were replaced with the W78. It is publicly estimated that 1083 warheads were manufactured.

<span class="mw-page-title-main">W50 (nuclear warhead)</span> Nuclear weapon

The W50 was an American thermonuclear warhead deployed on the MGM-31 Pershing theater ballistic missile. Initially developed for the LIM-49 Nike Zeus anti-ballistic missile, this application was cancelled before deployment. The W50 was developed by Los Alamos National Laboratory. The W50 was manufactured from 1963 through 1965, with a total of 280 being produced. They were retired from service starting in 1973 with the last units retired in 1991.

<span class="mw-page-title-main">W87</span> American thermonuclear missile warhead

The W87 is an American thermonuclear missile warhead formerly deployed on the LGM-118A Peacekeeper ("MX") ICBM. 50 MX missiles were built, each carrying up to 10 W87 warheads in multiple independently targetable reentry vehicles (MIRV), and were deployed from 1986 to 2005. Starting in 2007, 250 of the W87 warheads from retired Peacekeeper missiles were retrofitted onto much older Minuteman III missiles, with one warhead per missile.

<span class="mw-page-title-main">W49</span> US thermonuclear warhead of the 1950s and 60s

The W49 was an American thermonuclear warhead, used on the Thor, Atlas, Jupiter, and Titan I ballistic missile systems. W49 warheads were manufactured starting in 1958 and were in service until 1965, with a few warheads being retained until 1975.

<span class="mw-page-title-main">W62</span> American thermonuclear warhead designed in the late 1960s

The W62 was an American thermonuclear warhead designed in the 1960s and manufactured from March 1970 to June 1976. Used on some Minuteman III ICBMs, it was partially replaced by the W78 starting in December 1979, and fully replaced by W87 warheads removed from MX Peacekeeper missiles and retired in 2010.

<span class="mw-page-title-main">W56</span> American thermonuclear warhead designed in the late 1950s/early 1960s

The W56 was an American thermonuclear warhead produced starting in 1963 which saw service until 1993, on the Minuteman I and II ICBMs.

<span class="mw-page-title-main">W58</span> Nuclear weapon

The W58 was an American thermonuclear warhead used on the Polaris A-3 submarine-launched ballistic missile. Three W58 warheads were fitted as multiple warheads on each Polaris A-3 missile.

The W67 was an American thermonuclear warhead developed from June 1966 but then cancelled prior to any production or service use approximately 18 months later.

ET.317 was a thermonuclear weapon of the British Royal Navy, developed for the UK version of the UGM-27 Polaris missile.

W60 may refer to:

References

  1. History of the Mk 59 Warhead (Report). Sandia National Labs., Albuquerque, NM (USA). 1968. p. 7. Archived from the original on 2021-12-01. Retrieved 2021-11-06.
  2. 1 2 History of the Mk 59 Warhead, p. 8.
  3. History of the Mk 59 Warhead, p. 5.
  4. History of the Mk 59 Warhead, p. 9.
  5. History of the Mk 59 Warhead, p. 10.
  6. History of the Mk 59 Warhead, p. 13-14.
  7. History of the Mk 59 Warhead, p. 14.
  8. 1 2 3 Sublette, Carey (12 June 2020). "Complete List of All U.S. Nuclear Weapons". Nuclear weapon archive. Archived from the original on 2009-02-27. Retrieved 2021-11-05.
  9. History of the Mk 59 Warhead, p. 17-8.
  10. History of the Mk 59 Warhead, p. 18-19.
  11. History of the Mk 59 Warhead, p. 18.
  12. History of the Mk 59 Warhead, p. 19.
  13. History of the Mk 59 Warhead, p. 6.
  14. History of the Mk 59 Warhead, p. 21.
  15. History of the Mk 59 Warhead, p. 22.
  16. DCI Briefing to Joint Chiefs of Staff (PDF) (Report). 1963-07-30. p. 20. Archived (PDF) from the original on 2021-11-06. Retrieved 2021-11-06.
  17. History of the Mk 59 Warhead, p. 16.
  18. 1 2 Hansen, Chuck (2001-03-01). "Beware the Old Story". Bulletin of the Atomic Scientists. 57 (2): 52–55. doi:10.2968/057002015. ISSN   0096-3402. Archived from the original on 2021-11-06. Retrieved 2021-11-06.