The Peacekeeper ICBM was equipped to carry the W87 warhead. The W87 is one of four Lawrence Livermore designed warheads in the US stockpile. On 19 September 2005 the Air Force pulled the final Peacekeeper missile from alert status. Work on the deactivation began in October 2002. Some of the W87 Peacekeeper warheads were redeployed on Minuteman ICBMs under the Safety Enhanced Reentry Vehicle (SERV) program. Each W87 warhead will displace one W62, or three W78 warheads currently deployed on Minuteman. A number of W78 and W87 warheads will be retained as reliability replacements and surveillance assets to support the responsive force.
In March 1986, the first production unit of the W87 warhead for the Peacekeeper intercontinental ballistic missile (ICBM) was completed at the Pantex plant, culminating a four-year advanced development program. Peacekeeper carries 10 independently targetable Mk21 reentry vehicles with W87 warheads. The Peacekeeper came into service in the 1980s, and its warhead was one of the last "new " designs developed by US Department of Energy design agency physicists.
The W87 design is unique for strategic ballistic missile systems in its use of an insensitive high explosive and a fire-resistant pit design; both features help to minimize the possibility of plutonium dispersal in the event of an accident. The enhanced safety design features of the W87 were incorporated early in the development program when the Air Force was considering basing schemes with moveable missiles.
The W87 warhead/Mk21 reentry vehicle (RV) is the leading candidate for a single RV option for the Minuteman III ICBM. It is the most modern and safe U.S. nuclear warhead. It incorporates all "Drell" safety features: Insensitive High Explosive, a Fire Resistant Pit, and an Enhanced Nuclear Detonation Safety.
During 1990 and 1991 the production programs for the Nuclear Depth/Strike Bomb (B90), Follow-on-to-Lance (FOTL), and Small ICBM (W87-1) were terminated because their DOD delivery/platform systems were placed on indefinite hold or terminated.
The US has decided to retire Peacekeeper ICBMs and to deploy a large fraction of its W87 warheads on Minuteman III missiles. To prepare for long-term continuing deployment of the W87, a Life Extension Program for the W87 began in 1995 and modifications are being made to the W87s at Pantex. Formal certification of the refurbished warheads without nuclear testing was an important early test of new capabilities developed under the Stockpile Stewardship Program.
The life extension program on the W87 warhead was authorized by the Nuclear Weapons Council (NWC)
in FY 1994. Livermore's W87 Life Extension Program, begun in late 1994, met all its major milestones.
The program achieved First Production Unit (FPU) in the second quarter of FY 1999. The Major Assembly Release was delivered to the DoD in June 1999. Refurbishment of the W87 ICBM warhead (the design with the most modern safety features in the stockpile) extends the lifetime of the weapon to beyond 2025.
W87 refurbishment activities involve the Pantex, Kansas City, and Y-12 plants. Livermore involved the plants early in the design phase of the SLEP to ensure that the developed design meets performance requirements and can be produced efficiently, cost effectively, and with high quality. Operations at the Y-12 plant have provided the greatest challenge for the W87 SLEP because of the suspension of many operations at that facility. Refurbished W87s are delivered to the Air Force after assembly at the Pantex Plant.
No additional nuclear testing of the W87 is required to assure system reliability. Assessment
of nuclear performance and subsequent certification are based on computer simulation, past nuclear
tests, and new aboveground experiments that address specific physics issues.
The ongoing work at Pantex enhances the structural rigidity of the warhead and is increasing the service life by 30 years. The warhead will be mated to the Minuteman III missile following deactivation of the Peacekeeper missile. The NWC accepted the refurbished W87 as a standard stockpile item in the first quarter of FY 2002. NNSA has completed work on over half of the W87 inventory and the remaining W87 stockpile will be refurbished by the first quarter of FY 2004.
The W87 is being refurbished in order to enhance the structural integrity of the warhead. This includes small modifications to the primary, replacement of some non-nuclear components in the warhead, and refurbishment of some secondary components. The W87 Life Extension Program is the refurbishment of the W87 nuclear warhead to enhance its structural integrity and extend its stockpile life. Several major milestones were met in FY99. The design changes were approved by the DoD Design Review and Acceptance Group in May.
The W87 Life Extension Program is the first major weapon system refurbishment since the 1980s.
The W87, as is the case with every other weapon in the stockpile, has important components made at Y-12. And, as a complex precision machine, it must undergo periodic surveillance and maintenance to keep it in optimum working condition. An LEP, like the W87, results from findings and observations made during routine S&M activities and may involve modifications to one or more components to enhance safety and extend the weapon system 's shelf life.
In addition to introducing new technologies for the W87 LEP, required machine tools and material processes were restarted after almost a decade of disuse. Further, new requirements for electronically capturing manufacturing and inspection data to support certification without nuclear testing launched an effort to network machine tools on the factory floor. This secure network is being expanded under the auspices of the Stockpile Readiness Campaign. SRC also is including electronic data capture capabilities among its criteria in selecting and deploying new equipment and technologies.
The test regime, or stockpile surveillance, includes periodic flight testing of instrumented test models of a given weapon -- as close to the real thing possible -- called Joint Test Assemblies, or JTAs. Although a W87 JTA goes through routine, periodic testing, Lawrence Livermore National Laboratory was interested in having flight test instrumentation that was not as intrusive into their parts as the existing JTAs. The concern with the conventional JTA-type flight tests is that it doesn't have the physics package critical parts. There is some instrumentation in there that is supposed to have the same mass properties as the real part. It's supposed to act like the real weapon, but it's not the real thing, so there's always the question, 'Is this reality?' The closer tests can get to the real thing with elements like mass distribution, the more confidence there is in the test data.
In a relatively new program supporting the W87 nuclear weapon, a Sandia team is designing so-called Enhanced Fidelity Instrumentation, or EFI, to provide more reliable data during W87 test flights. Compared to existing instrumentation, EFI is much smaller and holds the potential to provide more detailed information. In May 1998, the first flight of an EFI-configured W87 was conducted from Vandenberg Air Force Base. The payload, carried atop a Peacekeeper missile, performed nominally.
Weaponeers want to fly their parts as pristinely as possible. In other words, the driver behind the EFI program is the desire to have a telemetry package that occupies much less volume and thus causes much less perturbation on the system during testing than is currently the case.
The first EFI test flight, FTU-12 (flight test unit 12), conducted in coordination with the Stockpile Life Extension Program, carried out a wide range of flight characteristic measurements during the unit's arcing flight down the Pacific range. FTU-12, incorporated gyros, magnetometers, accelerometers, vibration sensors, pressure transducers, and other instruments, all far smaller than similar instruments carried in W87's traditional JTAs. The instruments gave weapon designers a highly detailed picture of how the weapon actually flies along its trajectory and what happens to it as it separates from the launch vehicle, spins up, and reenters the atmosphere.
In support of the May 1998 Peacekeeper flight test, Sandia performed mass properties measurements on two Mk21/W87 Joint Test Assemblies containing full charges of insensitive high explosives. Because this quantity of explosives is not normally allowed on the California site, extensive preparation that included ES&H, transportation, security, and project personnel was required. The shipment of the units, the mass properties measurements, and related activities all were successfully accomplished, with the flight test units delivered on time to Vandenberg AFB.
Enhanced Fidelity Instrumentation (EFI) enabled a new W87 Instrumented High Fidelity (IHF) flight test vehicle in 1999. This vehicle retains War Reserve (WR) similitude while incorporating a full suite of instrumentation allowing performance to be scored without perturbing vehicle dynamics. Analysis using data from a W87 IHF development test confirmed acceptable performance during second roll encounter -- a flight regime that had not been broadly understood.
Sandia developed the first Distributed Telemetry system scheduled to be flown on an Mk21/W87 flight test in early 1999. Traditionally, some weapon system components in flight tests were replaced by the telemetry instrumentation. The new architecture subdivides telemetry functions and circuitry into smaller modules, which can be distributed throughout the test vehicle in unused spaces, so that weapon components don't need to be removed. This enhances the ability to assess stockpile reliability and safety.
To get the highest possible fidelity in these tests, most weapon systems -- including the W87 -- now fly "high fidelity" test articles. These units carry no instrumentation. During flight, they are monitored using off-board sensors like radar and visual tracking. Tests incorporating these so-called hi-fi articles have yielded useful results, but there's only so much you can learn via remote sensing.
In 2000 the Laboratory's activities were directed toward final certification of the restockpiled weapons, which was expected in 2001. In summer 2000, the Lab finished a final set of ground tests. The Lab also flight-tested production verification units aboard a Peacekeeper missile launched in March 2000.
At the successful conclusion of a three-year testing and evaluation program a Major Assembly Release (MAR) authorized on Jan. 24, 2001, the unconditional use of the Alt 342 W87 Life Extension Program (LEP) warhead by the Air Force.
A group of California Weapon Interns successfully designed, built, and launched a highly instrumented W87 warhead -- Instrumentation Development Flight (IDF) 3 -- in June 2002. IDF-3, while also serving as a real-world weapon-training project for the interns, allowed Sandia to test some 10 different experimental technologies, including a broadband transmitter, a wireless system bus, a distributed transmitter, and two separate attitude and trajectory measurement systems. IDF-3 contained the first LIGA micro-system to fly on a warhead in a true test flight environment. A LIGA (German acronym for an X-ray lithography-based manufacturing process) spring enabled the development of an Environmental Sensing Device (ESD) that can accurately sense low levels of acceleration. The motion of the ESD spring and sense mass is fluid damped to assure smooth, long-term operation. This robust device is designed to play a key role in nuclear weapon safety architectures that use environmental sensing as part of their nuclear safety theme. Prototypes have been built and successfully tested.
A new high-G shock test method using the Sandia rocket sled track was invented, developed, and qualified in 2002 by Sandia for assessing weapons component subassemblies for survivability in penetration environments. The test capability enables Sandia to respond quickly and less expensively to future weapon requirements. Both W87 and B83 subsystems have been tested against the simulated hard target penetration shock delivered by this novel test method. A second method to test full systems impacting concrete targets under controlled impact conditions is under development.
A two-page spread in the 31 July 1995 issue of US News and World Report entitled "Shockwave," documented the annihilation and destruction that would be caused by a nuclear attack or a nuclear bomb going off. In this article is an illustration of the W-87 warhead.
In late 2004 the National Nuclear Security Administration (NNSA) completed the first leg of an ambitious program to ensure that the nation's aging nuclear weapons stockpile is capable of meeting national defense requirements without producing new warheads or conducting underground nuclear tests.
NNSA has successfully completed a life extension refurbishment program for the W87 nuclear warhead. The last W87 warhead to be refurbished rolled off the assembly line at the Pantex Plant after undergoing an extensive rebuild. The purpose of the W87 Life Extension Program (LEP) refurbishment is to extend the warhead's life by 30 years and to provide structural enhancements.
The W87 is an integral part of the nation's strategic defense. Completion of this important life extension program assures the continued safety and reliability of this vital part of the strategic nuclear deterrent.
The W87 LEP was the first refurbishment program conducted by the NNSA's nuclear weapons complex, and the first program since the early 1990s that featured full utilization of the production complex. NNSA sites that participated in the work included the Pantex Plant, the Y-12 National Security Complex, the Kansas City Plant, the Los Alamos National Laboratory, the Sandia National Laboratories, and the Lawrence Livermore National Laboratory.
The SERV program modifies the Minuteman III (MMIII) Reentry System (RS) to accept the Peacekeeper MK21 warhead, thus keeping the newest and safest warhead in the inventory. The MK21 will be deployed on MM III prior to the phase out of the MK12 warhead which is being driven by the pending decertification of this warhead by the Department of Energy (DOE). The SERV will modify the RS to accommodate differences in electrical and mechanical interfaces, system software, support equipment, and trainers along with nuclear surety and human intent certification. Test articles will be developed to support development and qualification testing, flight testing, systems integration, and weapon system-level testing. This document is for the RDT&E phase of SERV. The production phase is budgeted under Modification # 5911, PE 0101213F. The first SERV modification of an operational ICBM was accomplished in October 2006.
On 09 January 2009 the Air Force modified a cost plus incentive fee contract with Northrop Grumman Space Technology, Clearfield, Utah for $36,959,911. The contract will provide the Minuteman III Safety Enhanced Reentry Vehicle full rate production option. At this time, the entire amount has been obligated. 526 ICBMSG/PKE, Hill Air Force Base, Utah is the contracting activity (F42610-98-C-0001).
By early 2010 the Air Force began Full Rate Production 2 of the Safety Enhanced Reentry Vehicle program. In January 2010 the USAF completed an internal Mk21 Fuze Refurbishment Assessment Team analysis. The government has aggressively screened existing Mk21 fuzes to ensure the maximum potential number of usable assets for the warfighter. This latest assessment will provide the final refurbishment strategy to meet the warfighter's needs for the most reliable, capable and safest warhead in the inventory.
Join the GlobalSecurity.org mailing list