W68
Encyclopedia
The W68 warhead was the warhead
used on the UGM-73 Poseidon
SLBM missile. It was developed in the late 1960s at Lawrence Livermore National Laboratory
.
, the Mk 3 Reentry Vehicle must be much smaller than other US RVs [which are mostly 22 inches (558.8 mm) diameter and mostly 72 inches (1,828.8 mm) long sized].
The W68 had a design yield
of 40-50 kilotons.
s with 16 missiles each, for a total of 656 deployed missiles, at a density of about 10 warheads per missile.
used in the W68
led to decomposition of the explosive, separating the binder
and plasticizer
, which then caused deterioration of the detonators. This required the whole production run to be retired or remanufactured with LX-10 and LX-10-1 as new explosives from November 1978 through 1983; about 2,000 units were retired starting in 1977 rather than rebuilt.
The remaining 3,200 warheads remained in service longer, with the last units were retired in 1991.
Warhead
The term warhead refers to the explosive material and detonator that is delivered by a missile, rocket, or torpedo.- Etymology :During the early development of naval torpedoes, they could be equipped with an inert payload that was intended for use during training, test firing and exercises. This...
used on the UGM-73 Poseidon
UGM-73 Poseidon
The Poseidon missile was the second US Navy ballistic missile system, powered by a two-stage solid fuel rocket. It succeeded the Polaris missile beginning in 1972, bringing major advances in warheads and accuracy...
SLBM missile. It was developed in the late 1960s at Lawrence Livermore National Laboratory
Lawrence Livermore National Laboratory
The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...
.
Specifications
The W68 weighs 367 pounds (166.5 kg). The warhead's dimensions are not publicly known, however to fit the maximum load of 14 within the roughly 65 inches (1,651 mm) Poseidon payload fairingPayload fairing
Payload fairing is one of the main components of a launch vehicle. The fairing protects the payload during the ascent against the impact of the atmosphere . More recently, an additional function is to maintain the cleanroom environment for precision instruments.Outside the atmosphere the fairing is...
, the Mk 3 Reentry Vehicle must be much smaller than other US RVs [which are mostly 22 inches (558.8 mm) diameter and mostly 72 inches (1,828.8 mm) long sized].
The W68 had a design yield
Nuclear weapon yield
The explosive yield of a nuclear weapon is the amount of energy discharged when a nuclear weapon is detonated, expressed usually in the equivalent mass of trinitrotoluene , either in kilotons or megatons , but sometimes also in terajoules...
of 40-50 kilotons.
Production and deployment
A total of 5,250 W68 warheads were produced, the single largest production run of any American nuclear weapon model. It was manufactured starting in June 1970 and ending in June 1975. Each Poseidon missile could carry up to 14 warheads; at the peak deployment, there were 41 US Poseidon submarineSubmarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s with 16 missiles each, for a total of 656 deployed missiles, at a density of about 10 warheads per missile.
Safety issues and later service
Aging of the LX-09 Plastic Bonded ExplosivePolymer-bonded explosive
A polymer-bonded explosive, also called PBX or plastic-bonded explosive, is an explosive material in which explosive powder is bound together in a matrix using small quantities of a synthetic polymer...
used in the W68
led to decomposition of the explosive, separating the binder
Binder (material)
-See also:*Adhesive or Glue*Cement*Paint...
and plasticizer
Plasticizer
Plasticizers or dispersants are additives that increase the plasticity or fluidity of the material to which they are added; these include plastics, cement, concrete, wallboard, and clay. Although the same compounds are often used for both plastics and concretes the desired effects and results are...
, which then caused deterioration of the detonators. This required the whole production run to be retired or remanufactured with LX-10 and LX-10-1 as new explosives from November 1978 through 1983; about 2,000 units were retired starting in 1977 rather than rebuilt.
The remaining 3,200 warheads remained in service longer, with the last units were retired in 1991.