This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Variable yield" – news · newspapers · books · scholar · JSTOR(September 2009) (Learn how and when to remove this message)
Variable yield, or dial-a-yield, is an option available on most modern nuclear weapons. It allows the operator to specify a weapon's yield, or explosive power, allowing a single design to be used in different situations. For example, the Mod-10 B61 bomb had selectable explosive yields of 0.3, 5, 10 or 80 kilotons, depending on how the ground crew set a dial inside the casing when it was loaded onto an aircraft.
Variable yield technology has existed since at least the late 1950s. Examples of variable yield weapons include the B61 nuclear bomb family, B83, B43, W80, W85, and WE177A warheads.
Most modern nuclear weapons are Teller–Ulam design type thermonuclear weapons, with a fission primary stage and a fusion secondary stage which is collapsed by the energy from the primary. These offer at least three methods to vary yield:
Varying primary yield by boosting with fusion, using small amounts of deuterium / tritium (DT) gas inside the primary fission bomb to increase its yield by supplying additional neutrons from DT fusion at the beginning of the fission process. Typically, the gas is injected a few seconds before detonation and the amount used can be preset – e.g., zero, 25%, 50%, or all of the gas.
Changing the primary yield by varying the timing or use of external neutron initiators (ENIs).[1] These are small particle accelerators that cause a brief fusion reaction by accelerating deuterium into a tritium target (or potentially vice versa), producing a short pulse of energetic neutrons. Precise timing of the ENI pulse as the nuclear primary's pit is collapsing can significantly affect yield, and the rate of neutron injection can also be controlled.
Shutting down the thermonuclear secondary, either by firing the primary at low enough yield that it does not compress the secondary sufficiently to ignite, or by blocking energy transport inside the warhead briefly as the primary is firing using shutters or a similar mechanism. If the primary's energy starts to disperse through the radiation case before being focused on the secondary then the secondary will likely never detonate.
All current British nuclear warheads incorporate variable yield technology as standard.[2]
Variableyield, or dial-a-yield, is an option available on most modern nuclear weapons. It allows the operator to specify a weapon's yield, or explosive...
is a variable-yield thermonuclear gravity bomb developed by the United States in the late 1970s that entered service in 1983. With a maximum yield of 1...
nuclear weapons, but larger ones are still very powerful, and some variable-yield warheads serve in both roles. For example, the W89 200 kiloton warhead...
The explosive yield of a nuclear weapon is the amount of energy released such as blast, thermal, and nuclear radiation, when that particular nuclear weapon...
low-to-intermediate yield strategic and tactical nuclear weapon featuring a two-stage radiation implosion design. The B61 is of the variableyield ("dial-a-yield" in...
The B43 was a United States air-dropped variableyield thermonuclear weapon used by a wide variety of fighter bomber and bomber aircraft. The B43 was developed...
ballistic missile (ICBM). The announcement stated the warhead had a variableyield "the explosive power of which is adjustable from tens kiloton to hundreds...
like a large bomber or naval base. However, yields can overlap, and many weapons such as the variableyield B61 nuclear bomb which could be used at low...
Yield management is a variable pricing strategy, based on understanding, anticipating and influencing consumer behavior in order to maximize revenue or...
variableyield, whereby the explosive energy of the device may be varied between a low setting for use in shallow or coastal waters, and a high yield...
and instead features a plastic guard of some sort. The W80-0 has a variableyield of 5 or 150 kilotons. 367 W80-0 warheads were produced. The AGM-86 ALCM...
was a variableyield fission weapon using a levitated pit and an implosion design using 92 high explosive lenses. The weapon had multiple yields of 8,...
(350 kg). The B90's yield has been described at both 200 kilotons of TNT (840 TJ) and "low kt". This may indicate a variableyield weapon. The B90 was...
In agriculture, the yield is a measurement of the amount of a crop grown, or product such as wool, meat or milk produced, per unit area of land. The seed...
use of an external neutron source allows more flexibility, such as variableyields. The usual design is based on a combination of beryllium-9 and polonium-210...
by a mechanical timer and had a variableyield equivalent to between 10 tons and 1 kt of TNT. A field non-variableyield version of the W54 nuclear device...
The TN 90 was a variableyield thermonuclear warhead developed by France for the Hadès tactical missile, designed to replace the AN 51/Pluton system. Development...
August 2007, six AGM-129 ACM cruise missiles, each loaded with a W80-1 variableyield nuclear warhead, were mistakenly loaded onto a United States Air Force...
seven-minute flight-time (which makes launch on warning much harder), variableyield warhead of 5-50 kt, and range of 1,800 km (1,100 mi), allowed this weapon...
A random variable (also called random quantity, aleatory variable, or stochastic variable) is a mathematical formalization of a quantity or object which...
In road transport, a yield or give way sign indicates that merging drivers must prepare to stop if necessary to let a driver on another approach proceed...
Global Information