Sandia News

Nuclear weapons engineering

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W76-0 and W88 Systems Engineering (2138) collaborated with Fire and Aerosol Sciences (1532) to successfully perform a test at the Cross Wind Test Facility to assess the W76-0 arming, fuzing, and firing subsystem in a simulated, fully-engulfing hydrocarbon fuel fire. Temperature and pressure data, video, and computed tomography were used to determine the state of critical components and integrity of the exclusion region to ensure confidence that nuclear safety would not be affected by the defined environment. (1500, 2100) NW

The prediction of the effect of short-pulsed neutron radiation has been extended to circuit-level. The program to develop qualification alternatives to the Sandia Pulsed Reactor achieved a major milestone by creating a model that predicts the response of a weapon-representative silicon circuit to short-pulsed neutron radiation like that formerly produced by the retired Sandia Pulsed Reactor. In comparing these predictions to validation data, the model was shown to capture major features of the circuit response, including the onset of non-linear threshold behavior as the neutron fluence increases, which have important implications for quantifying margins and uncertainties for silicon analog circuits. (1300, 1100, 1400, 1700) NW

On Aug. 20, 2010, Sandia and dignitaries from Congress and the NNSA celebrated the grand opening of the new Ion Beam Laboratory. This state-of-the-art facility houses a unique set of tools to perform basic and applied nuclear research and address an array of national security needs, including certifying nuclear weapons components. The construction project met its schedule and its success is due to the high degree of cooperation between the Radiation-Solid Integrations Department, Facilities, Purchasing, Security, ES&H, the Summit and Henderson construction teams, and the Sandia Site Office. (1100) NW

Because of concerns over environmental lead, legislated requirements and industry standards are replacing lead-tin solders with lead-free solders in future component designs and in replacements and retrofits. To support this effort, the Materials Science Center and the Engineering Sciences Center collaborated to develop, validate, and exercise a solder lifetime model that captures the thermomechanical response of lead-free solder joints in stockpile components. The model has been successfully used to support lead-free solder materials selection for stockpile component designs. (1800, 1500) NW

A new Power-free Gas Sampler (PGS) was developed and qualified for use on the B61 weapon. The PGS is being used at the Pantex Plant to collect surveillance gas samples during the B61 disassembly and inspection process, replacing the electrically powered Phoenix cart. The PGS operates off compressed air and does not require house power. This allows it to be used even when lightning warnings have been issued, resulting in a considerable improvement in the Pantex throughput. (1800, 2100, 00400) NW

Sandia researchers conducted a 90-day feasibility study for the Office of the Secretary of Defense of a common arming, fuzing, and firing (AF&F) system for the W78/Mk12A and W88/Mk5 warheads, with excursions of the AF&F for high-surety warheads and the W87/Mk21 system. The study found that significant levels of AF&F commonality are possible with existing system architectures that support use in the Mk5, Mk12A, and Mk21 re-entry systems and enable modernization goals for the future stockpile. (500, 2100, 2500, 2600, 2900, 5300) NW

NNSA authorization to commence with dismantlement activities for the B53 bomb was approved in September 2010. Sandia significantly contributed technical information and evaluation for the safe design of the B53 dismantlement process and special tooling. This significant Level II milestone accomplishment involved several years of activity. Sandia is the design agency for the B53 non-nuclear components. The B53, a bomb weighing approximately 10,000 pounds, was introduced in the nuclear weapon stockpile during the 1960s and was retired during the 1990s. (2100, 400, 1800)

NW On Sept. 30, 2010, Sandia completed the Cycle 15 (FY10) Annual Assessment with the release of Laboratory Director Paul Hommert’s letter to the secretaries of energy and defense and to the chair of the Nuclear Weapons Council. Issues addressed in the assessment this year included the need for the B61 Life Extension Program, neutron generator production workload, the need to transform our stockpile evaluation approach and the Kansas City Responsive Infrastructure and Sourcing activity. The work conducted for this year’s assessment involved hundreds of Sandians across the Laboratories. (2200)

NW A new approach to manufacturing thermal batteries was developed and is being transferred to an external supplier to support production of new battery designs for future weapon systems. A new binder technology was developed to allow spray coating of thin-film battery materials to replace conventional pressed powder pellets. Benefits of the new approach include significantly reduced weight and volume, lower manufacturing costs, and flexibility in form factor. The binder is low-cost and also has potential utility in lithium-ion and other commercial battery applications. (2500) NW

The Weapon Intern Program graduated its 12th class in August 2010, for a total of 242 graduates (154 Sandians and 88 non-Sandians) since its inception in FY99. The 11-month, full-time program assists in the transfer of decades of nuclear weapon-related knowledge and experience. FY10 participants included staff from Sandia/New Mexico and California, the US Air Force, the Air Force Nuclear Weapons Center, Los Alamos National Laboratory, NNSA, Honeywell/Kansas City Plant, Pantex, and Y-12. (2900, 200, 1200) NW

On Sept. 21, 2010, a B52-H successfully released an air-launched cruise missile carrying the new W80-1 JTA8 design. This first JTA8, produced in September 2009, replaced the 27-year-old JTA1R design for the W80-1. The instrumentation in the JTA8 has a higher sampling rate and fidelity than the JTA1R, which will allow more data to be collected and provide more surveillance information for both Sandia and Lawrence Livermore National Laboratory. It also addressed sunset technologies that had impacted the JTA1R, while decreasing production unit costs. (2900, 8200) NW

The Tritium Thermoelectric Generator (TTG) team demonstrated a functional prototype milliwatt generator. This milestone is the result of a significant engineering effort including end-to-end subcomponent simulation, prototyping, and testing. Project scientists characterized materials and manufacturing processes key to meeting TTG requirements. Component maturation is on an aggressive schedule and risks are reduced through a combination of engineering development, performance and environmental testing, materials characterization, and multiphysics simulations involving personnel from various centers across Sandia and other NNSA sites. (2500, 8200, 1500, 8100, 8300, 8600, 1800) NW

The W80-1 JTA8 joint test assembly had its first successful flight on an Air Force Air-Launched Cruise Missile (ALCM) at the Utah Test and Training Range in September 2010. The JTA8 is a new instrumentation system designed to provide data to assess the performance and reliability of the W80-1 warhead. All indications show that the JTA8 reached target as intended and all analysis indicates this to be a successful test for both the DoD and NNSA. (8200, 8100, 2900, 0400) NW, IHNS

On July 23, 2010, the 500th Arming and Fuzing Subsystem (AFS) was accepted by NNSA through the Quality Assurance Inspection Procedure. Sandia’s Radar Fuzing Department provides design and management support for this key component of the Navy’s W76-1 Arming, Fuzing and Firing (AF&F) system manufactured by Honeywell’s Kansas City Plant. The AFS is a highly integrated assembly that performs the missile interface, programmer, re-entry sensor, data multiplexer, and radar functions for the AF&F. (5300 1700, 400) NW

Sandia’s Stockpile Evaluation Program tested eight W76-1 laboratory samples at the Weapon Evaluation Test Laboratory (WETL), providing critical data for system assessment and for Pantex and Kansas City production. Also, data from the first four W76-1 surveillance flight tests were analyzed, providing verification that the system operates through space flight environments. In addition, the first W76-1 United Kingdom trials test was performed at WETL, providing qualification data critical to the UK implementation of the W76-1. (2900, 2100) NW

Always/Never: The Quest for Safety, Control & Survivability is a first-person documentary film about the use, control, detonation safety, and survivability of US nuclear weapons with an emphasis on the contributions of the DOE/NNSA nuclear weapon laboratories from 1945 to 1991. Exploring the historical interaction between technology, military operations, and national policy has never before been told in this detail. This video represents approximately five years of dedicated effort by Sandia’s Video Services Department, led by producer Dan Curry, and sponsored by Div. 1000 VP Steve Rottler. (1000, 2000, 3600) NW

Bootstrap Uncertainty Analysis is a new tool that allows system-level reliability uncertainty to be quantified routinely. This is an enhancement to assessment that will be used internally as a decision tool. It can be used to optimize the allocation of surveillance resources. It will allow surveillance to understand the value and risk associated with performing additional or fewer tests. The tool has been deployed using MATLAB and allows the user to specify hypothetical sample sizes and failure rates to assess the impact on system-level uncertainty. (0400, 2900) NW

The W62 dismantlement program safely and securely retired the 1970s-era warheads, taking apart the last unit in August 2010, a full year ahead of schedule. Lawrence Livermore and Sandia designed the W62 warhead for the Air Force Minuteman III intercontinental ballistic missile. The dismantlement process includes four steps: retiring a weapon from service; returning it to NNSA’s Pantex Plant; physically separating the high explosives from the special nuclear material; and processing the material and components. (8200, 2900) NW

The initial draft of the B61 Life Extension Program (LEP) System-level Nuclear Safety Specification (NS) and Fault Tree for Option 2C was completed Sept. 24, 2010. The initial NS includes the safety theme, conceptual implementation, assertions, initial derived requirements, and rationale. The NS also captures derived interface requirements with Los Alamos National Laboratory. By having this early Phase 6.2 safety framework at the system level, the LEP is positioned to provide early requirement definition to subsystems and components, resulting in earlier design definition, hardware, and more time to improve designs. (0400) NW

Haptic Environment for Realization and Analysis (HERA) software enables 3-D stereoscopic visualization, dynamic sectioning, hide/show, fly-through capabilities, and virtual reality (VR) simulations of ProEngineer models. HERA is Sandia-subsidized and available for use by the Sandia design community via PC. It facilitates design error-proofing and training assembly/disassembly technicians. VR simulations using the B61- 3,4,10, -7,-11, W76-1, W78, and W88 models were accomplished using integrated wireless gloves, head-tracking and head-mounted display. Future applications include the B61 Life Extension Program and Accident Response Group. (0400) NW (6500) ECIS, IHNS

Each citation is followed by the center numbers of centers that contributed most directly to the effort described. An acronym after each accomplishment indicates which of Sandia’s strategic management units (SMUs) or strategic management groups (SMGs) the work most directly supported.

The SMG/SMU acronyms are:

  • NW: Nuclear Weapons SMG & SMU
  • DS & A: Defense Systems & Assessments SMU
  • IHNS: International, Homeland, and Nuclear Security SMU
  • ECIS: Energy, Climate, and Infrastructure SMU
  • IES: Integrated Enabling Services SMU
  • WFO: Work for Others