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Ballistic impact flash plays a pivotal role in the ignition of fires in military vehicles. Flash duration, geometry, and energy profiles are critical variables in the assessment of ballistic-induced fires. The survivability community has identified a need for a standardized data collection methodology and corresponding valid community verified models. This effort will quantify existing test data and begin the process of producing dynamic models for flash geometry based on projectile and target material properties and impact conditions., The original document contains color images.

This report documents the research that was conducted to explore the unique concept of using crimp imbalance, which is a simple architectural modification achieved during the weaving process, as a potential mechanism to enhance fragmentation and ballistic protection levels of single-ply woven fabrics. It is shown in this report that crimp imbalance (1) can substantially influence the energy absorption levels of single-ply fabrics for select fragment simulating projectile velocities, friction coefficients, and impact angles; (2) can be tailored to controllably delay stress-wave propagations among yarn directions; and (3) can minimize reflections at the yarn crossover regions. This research, through single-ply numerical models, demonstrated that deviations in crimp contents can have significant effects on energy absorptions and projectile residual velocities; in short, optimal levels of crimp imbalance may exist for a specific ballistic threat type., The original document contains color images. All DTIC reproductions will be in black and white.

The dynamic deformation of transparent polymeric materials during the ballistic impact is investigated using a unique high-speed imaging technique. This technique involves the use of two high-speed cameras to record stereo images of a speckle patterned impact area and subsequent photogrammetric analysis. Photogrammetry is an image correlation technique that determines geometric properties, such as the displacement and strain history of a deformation event, by tracking the minute changes in the speckle pattern on the area of interest. These minute changes are then translated into three-dimensional displacement vectors as a function of time. Important mechanical behavior, such as strain or shear angle, can be calculated from the displacement vectors. By combining high-speed photography with photogrammetry, a full-field view on the strain as a function of time is made possible, and the strain can be resolved into components, such as the principle strain and shear strain. To demonstrate the capability of the high-speed photogrammetric technique, impact measurements on two different polymers were performed. A steel spherical projectile with a diameter of 5.54 mm and a weight of 0.692 g was used to impact a rigid polycarbonate (PC) and a flexible poly(urethane urea) (PUU) elastomer. The measurements were carried out at striking velocities between 100 m/s and 200 m/s, below the ballistic limits of both materials. At low impact speeds, the strain histories revealed that PC had a smaller deformation zone than PUU. At high impact speeds, it was observed that PC suffered a permanent strain deformation, whereas the strain in PUU relaxed over time. From these impact experiments, it is demonstrated that high-speed photogrammetry is able to capture the different strain behavior of these two polymers. These real-time strain histories cannot be easily observed quantitatively by other methods., Published in the Proceedings of the American Society for Composites 2009 (24th) Technical Conference, held in Newark, DE on 15-17 September 2009. The original document contains color images.

This report extends the work of Andrew A. Thompson described in the report titled Ballistics Filtering, ARL-TR-4735, published in March 2009, by showing the process of realizing the ideas through a simulation. By providing a concrete example it is hoped other realizations of the ideas can be pursued with a reasonable effort. Ballistic Filtering describes the dynamic equations that can be used to form Extended Kalman Filters (EKF) for the estimation of a projectile's trajectory. The steps associated with initialization and implementing an EKF are demonstrated through a specific task. The performance of an EKF processing Global Positioning System (GPS) observations is compared to the performance of an EKF processing both GPS and axial accelerometer observations., The original document contains color images.

These briefing charts discuss current demand data, government cost/benefit analysis, ballistic depth of penetration and summary. TARDEC and TACOM took up the challenge to develop a tool for decision makers to find the break-even cost for new materials that improve transparent armor performance. The initial Cost-Benefit Methodology for the M114 (HMMWV) Windshield has been extended to the Tactical Fleet Glass. A two-phase, 26 month basic research effort yielded a nanostructured, spinel with > 80% in-line transmittance in the visible range. Ballistic DOP tests comparing commercially available large grained spinel with nanostructured spinel are inprocess at TARDEC., The original document contains color images.

Firearm identification is an intensive and time-consuming process that requires physical interpretation of forensic ballistics evidence. Especially as the level of violent crime involving firearms escalates, the number of firearms to be identified accumulates dramatically. The demand for an automatic firearm identification system arises. This chapter proposes a new, analytic system for automatic firearm identification based on the cartridge and projectile specimens. Not only do we present an approach for capturing and storing the surface image of the spent projectiles at high resolution using line-scan imaging technique for the projectiles database, but we also present a novel and effective FFT-based analysis technique for analyzing and identifying the projectiles.

This paper presents the results of a series of experiments on the condensed phase decomposition and the gas phase combustion of hydrazinium nitroformate (HNF). The experiments include SEM analysis of quenched samples that showed evidence of the formation of a foam layer. FTIR spectrometry and mass spectrometry provide details on species formation during decomposition and combustion. The analysis of the results led to the identification of probable overall reactions in the low pressure regime around 0.1 MPa. It is found that decomposition of HNF takes place through formation of ammonium nitroformate, and through dissociative vaporisation. The gas phase near the surface of burning HNF is expected to contain a large amount of hydrazine, ammonia and nitrogen dioxide (as a decomposition product of nitroform). The primary reaction zone of the HNF flame is then associated with the exothermic reactions of these species. The resulting nitrogen oxide is subsequently reduced to molecular nitrogen in the secondary flame. © 2009 The Combustion Institute.

The availability of powerful computers these days increasingly enables the use of CFD for the numerical simulation of explosion phenomena. The BLAST software consists of a compilation of codes for the numerical simulation of the gas dynamics of explosions. Each individual code has been tailored to a specific application. After a brief introduction to the basic structure of the software, its potentials have been demonstrated in an exposition of applications to a variety of explosion problems.

Firearm identification is an intensive and time-consuming process that requires physical interpretation of forensic ballistics evidence. Especially as the level of violent crime involving firearms escalates, the number of firearms to be identified accumulates dramatically. The demand for an automatic firearm identification system arises. This chapter proposes a new, analytic system for automatic firearm identification based on the cartridge and projectile specimens. Not only do we present an approach for capturing and storing the surface image of the spent projectiles at high resolution using line-scan imaging technique for the projectiles database, but we also present a novel and effective FFT-based analysis technique for analyzing and identifying the projectiles.

Various open-literature experimental findings pertaining to the ballistic behavior of glass are used to construct a simple, physically based, high strain-rate, high-pressure, large-strain constitutive model for this material. The basic components of the model are constructed in such a way that the model is suitable for direct incorporation into standard commercial transient non-linear dynamics finite-element based software packages like ANSYS/Autodyn [ANSYS/Autodyn version 11.0, User documentation, Century Dynamics Inc. a subsidiary of ANSYS Inc.; 2007.] or ABAQUS/Explicit [ABAQUS version 6.7, User documentation Dessault systems, 2007.]. To validate the material model, a set of finite element analyses of the Edge-on-Impact (EOI) tests is carried out and the results compared with their experimental counterparts obtained in the recent work of Strassburger et al. [Strassburger E, Patel P, McCauley JW Kovalchick C, Ramesh KT, Templeton DW. High-speed transmission shadowgraphic and dynamic photoelasticity study of stress wave and impact damage propagation in transparent materials and laminates using the edge-on impact method. In: Proceedings of the twenty-third international symposium on ballistics. Spain: April 2007, and Strassburger E, Patel P, McCauley W, Templeton DW. Visualization of wave propagation and impact damage in a polycrystalline transparent ceramic-AlON. In: Proceedings of the twenty-second international symposium on ballistics. Vancouver, Canada: November 2005.]. Overall a good agreement is found between the computational and the experimental results pertaining to: (a) the front-shapes and propagation velocities of the longitudinal and transverse waves generated in the target during impact; (b) the front-shapes and propagation velocities of the coherent-damage zone (a zone surrounding the projectile/target contact surface which consists of numerous micron- and submicron- size cracks); and (c) the formation of crack centers, Published in the International Journal of Impact Engineering v36 p386 401, 2009.

The open-literature material properties for fiber and polymeric matrix, unit-cell microstructural characteristics, atomic-level simulations and unit-cell based finite-element analyses are all used to construct a new continuum-type ballistic material model for 0 deg/90 deg cross-plied highly-oriented polyethylene fiberbased armor-grade composite laminates. The material model is formulated in such a way that it can be readily implemented into commercial finite-element programs like ANSYS/Autodyn [ANSYS/Autodyn version 11.0, User Documentation, Century Dynamics Inc. a subsidiary of ANSYS Inc. (2007)] and ABAQUS/Explicit [ABAQUS version 6.7, User Documentation, Dessault Systems, 2007] as a User Material Subroutine. Model validation included a series of transient non-linear dynamics simulations of the transverse impact of armor-grade composite laminates with two types of projectiles, which are next compared with their experimental counterparts. This comparison revealed that a reasonably good agreement is obtained between the experimental and the computational analyses with respect to: (a) the composite laminates capability, at different areal densities, to defeat the bullets with different impact velocities; (b) post-mortem spatial distribution of damage within the laminates; (c) the temporal evolution of composite armor laminate back-face bulging and delamination; and (d) the existence of three distinct penetration stages (i.e. an initial filament shearing/cutting dominated stage, an intermediate stage characterized by pronounced filament/matrix de-bonding/decohesion and the final stage associated with the extensive back-face delamination and bulging of the armor panel)., Published in the Journal of Composites Part B: Engineering, v40 n6 p468-482, 2009. The original document contains color images.

A new ballistic material model for 0 deg /90 deg cross-plied oriented ultra-high molecular weight (UHMW) polyethylene fiber-based armor-grade composite laminates has been constructed using open-literature data for the fiber and polymeric-matrix material properties and the general experimental/field-test observations regarding the deformation and failure modes in these types of materials. The present model is an extension of our recently developed unit cell-based ballistic material model for the same class of composites (M. Grujicic, G. Arakere, T. He,W.C. Bell, B. A. Cheeseman, C.-F. Yen, and B. Scott, A Ballistic Material Model for Cross-Plied Unidirectional Ultra-High Molecular-Weight Polyethylene Fiber-reinforced Armor-Grade Composites, Mater. Sci. Eng, A 2008, 498(1-2), p 231-241) which was found to be physically sound, but computationally not very efficient. The present model is constructed in such a way that it can be readily integrated into commercial finite element programs like ANSYS/Autodyn (ANSYS/Autodyn version 11.0, User Documentation, Century Dynamics Inc., a subsidiary of ANSYS Inc., 2007), as a User Material Subroutine. To validate the model, a series of transient nonlinear dynamics computational analyses of the transverse impact of armor-grade composite laminates with two types of bullets/projectiles is carried out and the computational results compared with their experimental counterparts., Published in the Journal of Materials Engineering and Performance, v18 n9 p1169-1182, 2009. Supported in part by the U.S. Army/Clemson University Cooperative Agreements Contract nos. W911NF-04-2-0024 and W911NF-06-2-0042. The original document contains color images.

Glass impact experiments were designed at three different scales--0.22-cal, 0.375-cal, and 0.50-cal--named after the diameter of the bullets. Four experimental series were conducted at the three scale sizes: 1) Lexan-only experiments; 2) monoblock glass experiments; 3) single impact bonded glass experiments, and 4) multi-hit experiments. The experiments were conducted to obtain residual velocity as a function of impact (striking) velocity, including sufficient partial penetrations to calculate a V50. The Vs - Vr data were fit to the Lambert equation, Eqn. (5), to obtain another estimate of V50. Eroded lengths of the bullets were also measured. The objective of the experiments was to investigate whether a time dependency exists in glass damage/failure for ballistic experiments, and if so, try to quantify this dependency. No scale effect was observed in experimental results for the Lexan-only experiments. But a variety of scale effects were observed in the glass impact experiments, suggesting that there exists a time dependency to failure that is important within the timeframe of ballistic events.

Combustion Joining of refractory materials has great potential for low cost, rapid fabrication of composites, esp. for some materials that are difficult or impossible to join using more conventional techniques: Rapid combustion reactions provide a unique set of conditions for synthesizing functionally graded layers: short reaction times (1 10 s) allow the desired functionally graded material structure to be maintained Demonstrated the concept for joining of SiC-Al-alloy using a combustionbased approach Need to determine optimum reaction layer composition and heat-treatment conditions to form various phases: - Ti3SiC2 (ductile), Si(Al)CO, TiC-SiC-Al New press set-up /die design implemented to produce optimized materials for sub-scale ballistic tests., The original document contains color images.

A joint effort between the Georgia Tech Research Institute and the Army Research Lab successfully used a combination of numerical and experimental results to demonstrate the performance of a guidance actuator for a supersonic projectile. The use of computational and experimental approaches greatly enhanced the understanding of how the actuators worked as well enabled the program to be completed for a lower cost than if either the modelling or the experiments had been neglected. Wind tunnel experiments were used with computational fluid dynamics results to provide aerodynamic coefficients for six-degree of freedom (6-DOF) simulations. The 6-DOF simulations were used to predict the performance of the projectile in the range, thus ensuring that good range data were acquired and reducing the necessary number of set-up rounds. It was found that there were cases where experimental methods were necessary, although the modelling provided the researchers with a greater detail of flow interactions and provided forces that were difficult to measure., Published in the Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, v223 p341-355, 2009.

The U.S. Army Research Laboratory (ARL) is interested in assessing the performance of different magnesium alloys. The ARL and the Joining and Welding Research Institute (JWRI) conducted a joint effort to develop and evaluate advanced powder metallurgy magnesium alloys AZ31B and AMX602 (Mg-6Al-0.5Mn-2Ca/mass%) sheets. JWRI performed the mechanical and metallurgical analysis, while ARL performed the ballistic analysis. The thin gauge magnesium alloy sheets were ballistically evaluated against the 0.22-cal fragment simulating projectile (FSP). The powder magnesium alloys' mechanical properties and ballistic performance are compared to the conventionally processed AZ31B-H24., See also ADM002300. Presented at the Minerals, Metals and Materials Annual Meeting and Exhibition (138th) (TMS 2009) held in San Francisco, California on February 15-19, 2009. Sponsored in part by the Navy.

This paper describes properties, processing, and performance of Al-Zn-Mg alloy 7020 for armor and commercial applications. Comparisons are made with alternative aluminum armors' chemistry, properties, levels of strength and ductility, weld properties, and resistance to stress and exfoliation corrosion. The advantages for development and optimization of alloy 7020 for vehicle armor or welded structures are identified to be: (1) low thermal sensitivity of the microstructure and mechanical properties to deleterious effects from reheat or solution-treatment and air-quench, (2) low Zn-Mg alloy and production costs, (3) adequate thick-plate strength and ductility for ballistic protection, and (4) high levels of weld strength and ductility in the natural or artificial aged condition. Concerns include: (1) optimizing thickness-dependent combinations of strength, toughness, and armor-threat-protection; and (2) optimizing processing and manufacturing techniques for mechanical properties and durability against stress and exfoliation corrosion., See also ADM002300. Presented at the Minerals, Metals and Materials Annual Meeting and Exhibition (138th)(TMS 2009) Held in San Francisco, California on 15-19 February 2009. Published in the Proceedings of the Minerals, Metals and Materials Annual Meeting and Exhibition (138th)(TMS 2009), p3-9. 2009.

This report results from a contract tasking Lund Institute of Technology as follows: A high quality spray in cross-flow rig will be assembled. Our objectives are to build an atmospheric pressure channel with a length/wetted diameter ratio around 30 for a well developer air flow. We will inject water with Weber numbers in the range 50 - 300. Ballistic imaging will be applied to the jet core, while PIV/LDA will be used to describe the air flow. PDA will be applied to the dilute region of the spray and high-speed shadowgraphy will be used to observe the overall spray behavior. The data to be acquired include upstream dynamics of the air (images of velocity and vorticity via PIV and statistical moments via LDA), breakup dynamics (primary breakup and droplet characterization) of the jet in the near field (via ballistic imaging), droplet sizes and fluxes via PDA, and overall jet behavior via fast-framing shadowgraphy. The fast framing camera will be used in the event that oscillations in the core are imposed upon the free stream. A detailed database over a rage of Weber and Reynolds numbers, suitable for model validation, will be prepared and presented in several publications. If possible (if it can be fitted), an aerated injector, as used by AFRL, will also be evaluated. While operation with water at atmospheric pressure is not the same as operation with real fuels at realistic pressures, this work will produce a complete database that can be used to develop better understanding. Tests of more realistic systems can follow in coming years. Currently the only fully functional ballistic imaging system for spray studies is located at Lund., Prepared in cooperation with Sandia National Laboratories, Livermore, CA. Sponsored in part by Army Research Office (ARO), contract no. DAAD19-02-1-0221. The original document contains color images.

The purpose of this study is to develop a survival model of blast-induced traumatic brain injury (BI-TBI) in swine. Two air guns have been constructed, each having different lengths, air chamber volumes and barrel diameters. Using a digital ballistics chronometer the air velocity was measured over a series of firings at different controlled pressures in the air chambers. Calibration curves from both air guns show linear and reproducible results through a range of firing pressures. Behavioral/learning/memory testing has been developed which will detect cognitive and behavioral changes for up to 2 months following BI-TBI. To date swine have received BI-TBI with the air guns of two different sizes and were recovered for 7 days post injury. BI-TBI with the larger gun caused initial pain requiring analgesia and reduced weight gain compared to injury generated with the smaller gun. Brains will be examined for molecular markers of injury. Histology and immunocytochemistry will evaluate cytoarchitecture, degenerating neurons and morphology. When completed this swine model BI-TBI will provide a needed tool for use in developing treatment and rehabilitation of traumatic head injuries as well as improvements in military protective body armor., The original document contains color images.

Fragmentation is a key damage mechanism determining ballistic impact performance of ceramic armors as well as reliability of gun barrels. This program, which was sponsored by the Army Research Office, focuses on the relation between defect populations and fragment-size distributions via robust physics-based numerical simulations. The originality of the present simulations lies in the capability of dealing with fragmentation of large and heterogeneous structures. The understanding of how the microstructure acts on the global macroscopic response is our main concern. Defects are strategically placed during the design of a material or a structure in order to optimize the geometrical (shape and size) or velocity characteristics of fragments., Prepared in cooperation with Ecole Polytechnique Federale of Lausanne. The original document contains color images.

The Collaborative Australian Ballistics Research code, Casbar, is a simulation tool for the analysis of the interior ballistics of guns. The code solves a two-phase, axisymmetric form of the governing equations for the flow of gas and particulates in the gun, and accommodates multiple projectiles within the simulation. Casbar is also suitable for investigating intermediate ballistics, and can alternatively be used as a general compressible flow solver. Casbar supports user-customised types of deterred or undeterred propellant grain, flexible definition of initial conditions and ignition sources, and various constitutive submodels for simulating interphase drag and intergranular stress. This document, the Casbar User's Guide, explains the use of the code and available options, and provides a worked example with corresponding input files., The original document contains color images.

The U.S. Army Research Laboratory (ARL) was directed to investigate various ways to expand current steel armor plate production as the large military demand for armor plate exceeded the current production capacity at U.S. steel facilities for quench and tempered high-hard armor (HHA) steel plate. The solution was to expand the availability of HHA steels under the current HHA military specification (MIL-DTL-46100) to include a new class of air-quenched, auto-tempered steels that do not use existing water quench and temper facilities. Allegheny Technologies Incorporated (ATI) developed an auto-tempered steel alloy, ATI 500-MIL (trademark of ATI Properties, Inc.), that has physical and mechanical properties that meet the current HHA specification. ARL procured sufficient amounts of ATI 500-MIL plate to allow acceptance testing and subsequent certification of ATI 500-MIL plate as complying with the First Article requirements of the newly revised MIL-DTL-46100E specification. This report documents the development of ATI 500-MIL plate and subsequent ballistic testing and inclusion into the specification as Class-2 auto-tempered HHA steel., The original document contains color images.

Ballistic tests were carried out on the relatively new titanium alloy Ti-5A1-5V-5Mo-3Cr (Ti-5553), which was subjected to two heat treatment conditions. The two heat treatments provided high-strength plates which were solution treated and aged (STA) and high toughness plates that were beta-annealed, slow cooled and aged (BASCA). The ~13.9-mm-thick plates were evaluated for V50 using 0.50-cal. FSP and 0.30-cal. AP M2 projectiles. The results were benchmarked against MIL-DTL- 46077F and MIL-A-46077 D for weldable titanium alloy armor plate (Ti-6Al-4V). The BASCA plates exceeded the requirement for the 0.30-cal. AP M2 by 3.2% but fell short of the Ti-6A1-4V performance against the 0.50-cal. FSP projectiles by 11.3%. The STA plates exceeded the Ti-6A1-4V mil-spec requirement by 8.7% and 11.7% for the 0.30-cal. AP M2 and 0.50-cal. FSP projectiles, respectively., The original document contains color images.

A briefing on ballistic protection technology for tents and mobile shelters, including the MPBS(Modular Ballistic Protection System)., Presented at the Bi-Annual DOD JOCOTAS Meeting with Rigid & Soft Wall Shelter Industry & Indoor & Outdoor Exhibition (6th) held in Panama City Beach, FL on 2-4 Nov 2009. The original document contains color images.

This thesis investigates the use of porous materials in a multi-layered armor concept. The prototype layered structure consists of an initial high-strength material to slow down the projectile and cause significant plastic deformation, followed by an orthotropic wave-spreading layer to spread shock waves laterally away from the axis of penetration and subsequently attenuate the shock waves by using a porous material to convert kinetic energy into internal energy. Based on the above armor concept, composite plates consisted of an alumina (Al203)-based ceramic, Dyneema(trademark) and porous foams were constructed and tested against conventional armor steel of equivalent areal density. This study used two commercially available porous materials, one based on aluminum metal and one a rigid polyurethane foam. This study also investigated the effect of porous initial density of the polymeric foam on ballistic. The author developed a P-alpha compaction model for the chosen porous materials for use in AUTODYN(trademark) simulations to describe their dynamic compaction during an impact event. The author also conducted a ballistic trial to validate the performance of the armor laminate against numerical simulations. Based on the results of this study, the porous layer has proven to be a good shock attenuator. The porous material efficiently delays the shock wave propagation and attenuates the amplitude by absorbing the kinetic energy through compaction of the material. The current research has also proven that the material layering sequence is fundamentally correct and has its merits., The original document contains color images.

Recent congressional and media inquiries have highlighted questions regarding the protection provided to today's Marine Corps. The purpose of this research is to analyze the current Family of Ballistic Protective Systems (FBPS) Acquisition Strategy of the United States Marine Corps. The FBPS consists of individual protective items such as ballistic vests, individual armor plating, helmets, and eye and ear protection. Currently, the Marine Corps adheres to the (Department of Defense) DoD policy to use one-year appropriations to finance the procurement and sustainment of these items. Critics of the policy believe a separate three-year appropriation specific to the acquisition of these individual components better serves the customer and the acquisition process delineated in the DoD Instructions. The research examined current government regulations, policy environment, and acquisition precedents. Additionally, the research compared a previous FBPS acquisition to a theoretical procurement under three-year appropriations. The research determined that the three-year obligation period of procurement funding better serves the acquisition process. Furthermore, three-year appropriations provide a better value for the Marine Corps in terms of cost savings and a better product. Finally, the research provides specific recommendations for the Marine Corps in the area of future procurements in the FBPS., The original document contains color images.

Vacuum-assisted resin transfer molding is a promising, affordable technique for producing composite integral armor (CIA) and thick-section composites for U.S. Army-relevant applications. Among several constituents, the CIA uses S2-glass/epoxy and/or S2-glass/vinyl ester composites in its construction. The S2-glass-reinforced composite provides ballistic protection and load bearing due to the flexural loading caused from vehicle movement over various terrains. The S2-glass-reinforced composite is subjected to different levels of delamination when impacted by projectiles. The present study focuses on the repair of S2- glass/epoxy composites subjected to a clean perforation type of ballistic impact scenario and post-repair flexural response of the composite panels. Simple repair solutions involving the use of different plugs reinforcing the damage (12.7-, 25.4-, and 38.1-mm [0.5-, 1-, and 1.5-in] clean perforations) have been implemented in S2-glass/vinyl ester laminates. Static and fatigue tests were conducted under flexural loading. The effects of implementing the repair strategies on the flexure performance have been reported., The original document contains color images.

During an Army research program in the mid-1980s, fireresistant diesel fuel that self extinguished when ignited by an explosive projectile was developed. Chemically, this fire resistant fuel (FRF) was a stable mixture of diesel fuel, 10 percent water, and an emulsifier. The Army FRF program ended in 1987 without fielding this fire resistant fuel formulation. There were both technical and logistical reasons for this. Unconventional warfare experienced in Iraq and Afghanistan involving use of Improvised Explosive Devices (IED) has led the Army to restart the FRF program in an attempt to counter the increasing threat of fuel fires. Efforts are now underway to develop new Fire Resistant Fuel to reduce and/or eliminate both the initial mist fireball and any residual pool burning. Vehicle operation and environmental conditions commonly cause the temperature of the fuel in the vehicles to rise above its flash point, thus making it more susceptible to being ignited. This elevated fuel temperature, when combined with an ignition source such as a ballistic penetration near the fuel tank or fuel line, significantly increases the potential for a catastrophic fuel fire. This paper will discuss some of the aspects and limitations of developing a fire resistant fuel water emulsion and how the use of JP-8, as intended by the single fuel forward concept, affects this development., Presented at NDIA's Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), 17 - 22 August 2009,Troy, Michigan, USA, The original document contains color images.

The penetration behavior of Kevlar fabric intercalated with dry particles and shear thickening fluids (STF), highly concentrated fluid-particle suspensions, is presented. In particular, the role of particle hardness is explored by comparing fabric treatments containing SiO2 particles, which are significantly harder than Kevlar, to treatments containing softer poly(methyl methacrylate) (PMMA) particles. The fabric testing includes yarn pull-out, quasi-static spike puncture, and ballistic penetration resistance, performed on single fabric layers. It was found that both dry particle and STF treatments resulted in improvements in fabric properties relative to neat or poly(ethylene glycol) (PEG) treated fabrics. On comparison of treatments with different particle hardness, the SiO2 materials performed better in all tests than comparable PMMA materials, although the SiO2 treatments caused yarn failure in pull-out testing, reducing the total pull-out energy. In addition, resistance to yarn pull-out was found to be substantially higher for STF-treated fabrics than for dry particle treated fabrics. However, both dry particle addition and STF treatments exhibited comparable enhancements in puncture and ballistic resistance. These observations suggest that viscous stress transfer, friction, and physical entrainment of hard particles into filaments contribute to the demonstrated improvements in the properties of protective fabrics treated with shear thickening fluids., Published in ACS Applied Materials and Interfaces, v1 n11 p2602-2612, 25 Nov 2009; published online 3 Nov 2009. Prepared in collaboration with Materials Division, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD. The original document contains color images. All DTIC reproductions will be in black and white.

An efficient method was needed to perform ballistic testing using the 0.22-cal. fragment-simulating projectiles (FSP) at low subsonic velocities in order to evaluate very thin lightweight composite and metallic materials at around 1 lb/ft2 areal density. This technical note outlines the custom gun system developed to enable this ballistic testing., The original document contains color images. Project No. 1L162618AH80.

A test method was used to develop a process to emplace a refractory metal liner inside a gun tube as a part of an effort at the U.S. Army Research Laboratory to develop an autofrettage gun barrel application. The process consisted of filling the liner with an elastomeric material and then slipping this arrangement into the gun tube. The ends of the liner were plugged with plastic disks, and pressure was applied to the elastomeric material by a load frame. A test fixture was developed to facilitate containment and alignment of the gun barrel during testing. The fixture is described in this report, and preliminary data is provided to show the utility of the fixture., The original document contains color images.

USES OF NDE AND HEALTH MONITORING: *Health Monitoring during normal vehicle usage, before battle use or damage and performed at certain time intervals. * Determination of the severity, identification, and location of ballistic impacts to the armor while the vehicle is being used in battle. An active NDE system could tell the commander of any vulnerabilities and or what areas need repair to stay in battle. * Communication to neighboring forces integrity of armor and or severity of impacts. * Assessment of armor integrity between missions. This would be done at the depot level and would involve NDE and health monitoring to test for any armor defects or flaws as well as internal damage that could lead to armor failure. * There is a need for system integration at the armor level., Presented at NDIA's Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), held in Troy, MI, on 17-22 Aug 2009. Document consists entirely of briefing charts.

This TOP describes procedures for determining the deviation of the line of sight (LOS) of a sighting system (integrated), or gun/turret drive with respect to initial alignment with a target, without external inputs, as a function of time. Level and canted vehicle orientations are investigated to determine if any interaction exists between azimuth and elevation. The reader is referred to TOP 3-2-836 (0) Combat Vehicle Fire Control Systems - Overview Document or International Test Operations Procedure (ITOP) 3-2-836 (0) Combat Vehicle Fire Control Systems - Overview Document., The original document contains color images. This TOP supersedes ITOP 3-2-836(2.2.2), dtd 27 Jun 1985.

This document describes the procedures for determining the coincidence window of a tank fire control system. The coincidence window is defined as the limits around exact sight/gun alignment within which the gun is permitted to fire (omitting the offsets imposed by a ballistic solution). Typically, a combat vehicle implements the coincidence windows based on the current alignment (static) and in some cases additionally the future alignment (dynamic) of the sight and gun. Procedures for determining coincidence window performance (with and without gunner input) against the tank's coincidence window and a standard test window of 0.3 mrad x 0.3 mrad are included. The reader is referred to TOP 3-2-836 (0) Combat Vehicle Fire Control Systems - Overview Document or International Test Operations Procedure (ITOP) 3-2-836 (0) Combat Vehicle Fire Control Systems - Overview Document., The original document contains color images. This TOP supersedes IToP 3-2-836(2.2.3), dated 29 Jun 1995.

The U.S. Army Research Laboratory maintains capabilities for both external (ground-based, i.e., spark range) and onboard sensor system (telemetry- and recorder-based) methodologies for obtaining free-flight motion measurements of projectiles. These two methodologies were developed independently and until recently had been applied in projectile development programs without a thorough consideration of their synergistic interrelationship. Such a consideration is presented herein as a means for appropriating the benefits of each in a unified manner, thus making better use of available time and resources. A brief description of the two methodologies, their development histories, and their strengths and limitations is made. Complementary aspects are identified that can contribute to projectile development by accelerating progress, mitigating risks, and reducing costs. Future areas of instrumentation and technique advancement are cited that will positively impact the evolution of the complementary roles of ground- and telemetry-based methodologies., The original document contains color images.

The initial work statement targeted quantifying the hot working conditions experienced by titanium during friction stir welding/processing (FSW/P). Of particular interest was the identification of the hot working conditions (i.e. strain rate, strain, and temperature) required to refine the grains in the weld zone or nugget. Using a kinematic approach toward modeling of the FSW/P, the instantaneous shear strain rate encountered by the material entering the rotation plug around the weld tool is estimated to be in the range of 103 to 106 s-l at strains levels in excess of 50. A similar level of grain refinement has been reported in metal chips formed during cutting operations where the shear strain rate is estimated to be in the range of 103 to 106 s-l, but at strain levels less than 5. Both these processes are predicted to instantaneously impart strain rates on the order of ballistic impact on the metal. In contrast grain refinement has also been reported in equal channel angular extrusion (ECAE) where the grain size reduction has been correlated with the increasing amount of strain achieved by multi passes at quasi-static strain rates. The motivation for this study is furthering our understanding of the mechanics responsible for grain refinement as influenced by ballistic level sheer strain rate and/or shear strain., The original document contains color images. All DTIC reproductions will be in black and white.

This briefing looks at the use of fuzzy logic in non-destructive identification techniques. The method is based on the fact different impacting materials will generate different impact acoustic waves., Presented at The 2009 World Congress in Computer Science, Computer Engineering, and Applied Computing,in Las Vegas, NV on 13-16 Jul 2009. Prepared in collaboration with US Army RDECOM-TARDECE, Warren, MI. The original document contains color images.

X-ray computed tomography (XCT) is an important nondestructive evaluation technique for revealing the spatial distribution of ballistically induced damage in ceramics. The level of detection and resolution of damage depends on the size of the sample and the parameters of the XCT approach (e.g., focal spot size, magnification, etc.). Previous and ongoing work in this area includes assessment of ballistically induced damage in both individual ceramic targets and ceramic armor panels. Ballistic damage in an encapsulated ceramic armor panel with a metal backing has been scanned and extensively evaluated using XCT two- and three-dimensional (3-D) analysis. The purpose of using XCT evaluation in this study was to better characterize and understand all of the detectable damage. This information can be used to correlate damage features and types with the physical processes of damage initiation and growth. XCT scans and analyses of damage in the panel will be shown and discussed. This will include virtual 3-D solid visualizations and some quantitative analysis of damage features., The original document contains color images.

The dominant materials solution used for ballistic transparency protection of armored tactical platforms in commercial and military applications is low cost glass backed by polycarbonate. Due to the high cost of testing transparent ceramics, a modelling approach has been undertaken in parallel with ballistic testing to validate armor designs based on a transparent magnesium aluminate spinel, MgAl2O4, striking-ply backed by polycarbonate. Finite element modelling is used to predict unsuccessful designs and reduce number of laminate configurations in experimental testing. The purpose of this report is to demonstrate the importance of modeling tools in advancing ceramic transparent armor materials to fielded applications. The effect of various shape defects, located at various locations on the surface and in the interior of spinel hard face of the laminate target, on the failure of the transparent material will compared with relative available experimental data and they be discussed in detail., Published in the Proceedings of the International Symposium on Ballistics (24th) held in New Orleans, LA on 22-26 September 2008 v2 p760-767. The original document contains color images.

The present investigation is a continuation of our previous study on the ability of the phenomenological Johnson-Holmquist model to predict the observed damage induced by spheres of tungsten carbide (WC) striking confined cylinders of silicon carbide (SiC) at velocities between 63 m/s to 500 m/s. In this study, the WC was modeled using the Johnson-Cook plasticity model along with a principal stress failure criterion calibrated with recently available experimental data. Johnson-Holmquist model parameters along with modifications incorporated to brittle damage models included in AUTODYN tensile crack softening and stochastic failure were varied to study their influence on the simulated crack patterns. Comparisons with the cracking from the simulations and the experimentally observed damage are described and ongoing efforts to improve the numerical results are discussed., Presented at the International Symposium on Ballistics (23rd), held in Tarragona, Spain, on 16-20 Apr 2007. Published in the proceedings of the conference, v2 p1039-1047, 2008. The original document contains color images.

Lumped-parameter interior ballistics (IB) codes have had limited success in simulating the IB of mortars due to the complex nature of the firing event. Only near the end of the firing event does the mortar conform to the conventional ballistics model for which lumped-parameter codes were designed. Modified lumped-parameter models are capable of simulating some key mortar variables. There are significant pressure waves developed in mortars, which are due in part to the nonuniform discharge of combustion products from the flashtube. The mortar IB cycle is not only time dependant but is also very spatially complex. These pressure waves cannot be adequately represented in a one-dimensional IB model. Plans to modify the Army?s two- or three-dimensional IB code ARL-NGEN3 for mortar simulations are discussed. However, conventional NGEN modeling approaches cannot capture the nonuniform discharge of combustion products from the flashtube as shown in experiments. An improvement in gas generation tables and work on a two-phase turbulence model of a primer and black powder pellets with a velocity profile based on the one-dimensional turbulence modeling approach are presented. Plans for coupling this primer model to the ARL-NGEN3 code for mortars are discussed., The original document contains color images.

Traditionally, the interior ballistic (IB) modeling of mortars has been difficult to achieve because a mortar projectile contains certain energetic components internal to the tail boom. After ignition, high pressure generated by the igniter causes the canister to burst and release hot gases and burning particles into the larger chamber called the launch tube. Subsequently, any external charges ignite and produce gases which accelerate the projectile. A recent advancement to the IBHVG2 code allows the modeling of this high-low (HILO) configuration. This HILO feature comes with the introduction of two new parameters into the IBHVG2 model, essentially gas-phase and solid-phase discharge coefficients governing flow between the two chambers. The large-caliber gun community focuses on the impact of seven IB input variables (charge weight, force, propellant diameter, burning rate coefficient and exponent, covolume, and projectile weight) on the peak chamber pressure and projectile exit velocity. A sensitivity study on these input variables was performed on the high and low canister over a small range of the nominal value. The HILO feature was also examined for a 120-mm mortar. Uncertainty associated with the two new free parameters necessitated a wider range of investigation of said parameters., The original document contains color images. Prepared in collaboration with American Systems, Aberdeen, MD.

There are many models of ballistics trajectories. The high-resolution 6-degree-of-freedom (6-DOF) models require many computations and a small time increment. The modified point mass models ignore the spinning of the round to reduce the computational requirements. Selecting a model to use for ballistics estimation or tracking requires tradeoffs between system accuracy and computation expense. The purpose of this report is to present reduced state models (simpler than the 6-DOF model) that can be used to model the trajectories using an extended Kalman filter. These filters can be used to enhance the performance of smart munitions., The original document contains color images.

As technological advances continue to be made in the commercial sectors of portable and wireless communication products, additional advancements in battery technology have also been made. These advancements have allowed for the rapid growth of a large variety of commercially available batteries which have the capability to meet or even exceed the current power and size requirements for numerous ballistic telemetry systems. The replacement of a custom built battery with a commercial-off-the-shelf (COTS) battery would provide immediate advantages such as lower cost, shorter lead times, and higher availability. The overall objective of this report is to provide ballistic telemetry systems engineers and designers with a description of several low-cost, readily available COTS alternatives to traditional custom-made power sources., The original document contains color images.

Since 1995, the United States has provided North Korea with over $1.2 billion in assistance, about 60% of which has paid for food aid and about 40% for energy assistance. U.S. aid fell significantly in the mid-2000s, bottoming out at zero in 2006. The Bush Administration resumed energy aid in the fall of 2007, after progress was made in the Six-Party Talks over North Koreas nuclear program. The Six-Party Talks involve North Korea, the United States, China, South Korea, Japan, and Russia. The United States and other countries began providing heavy fuel oil (HFO) in return for Pyongyang freezing and disabling its plutonium-based nuclear facilities in Yongbyon. By the second week of December 2008, the United States had provided all of the 200,000 MT of HFO it had promised under this "Phase Two" of the Six-Party Talks process. Russia completed its promised shipments of energy aid in January 2009. China and South Korea appeared to be calibrating their Six-Party-related assistance to progress in disabling Yongbyon. North Korea's failed satellite launch on April 5, 2009, which used ballistic missile-related technology, led to U.N. Security Council condemnation. In response, North Korea said it would abandon the Six-Party Talks, would restart its nuclear facilities and asked international and U.S. inspectors to leave the country. The United States had been providing technical assistance to North Korea to help in the nuclear disablement process. In 2008, Congress took legislative steps to legally enable the President to give expanded assistance for this purpose. In its FY2009 Supplemental Appropriations budget request, the Obama Administration has asked for over $150 million for North Korea-related energy and denuclearization assistance. This money would supplement existing resources in the event of a breakthrough with North Korea. In separate committee actions, House and Senate appropriators denied these requests., CRS Report for Congress.

The main goal of this project is to develop a systematic mathematical theory for the robust real time feedback control and stochastic analysis of unsteady transonic aerodynamics of helicopter rotor blades, supersonic ballistic projectiles and propagation of blast waves in the presence of adverse external disturbances. The proposed work builds upon similar scientific advances by the principal investigator in the context of incompressible fluid dynamics, magneto-hydrodynamics and combustion models during the past two decades under ONR, DARPA and ARO sponsorship. The gas dynamic models to be used in the research will be either the Euler equations or the quasi- linear unsteady potential equations. These nonlinear hyperbolic or elliptic-hyperbolic type mixed equations are subjected to additive and multiplicative external disturbances modeled as Gaussian, Poisson and Levy type noise forces. Main results to be expected are mathematical characterization of entropy solutions for stochastic hyperbolic systems of conservation laws, state estimation and feedback control analysis as well as assessment of the impact of noise in controlled and uncontrolled aerodynamic flows of the above type. The outcomes of this research will be expected to impact a number of other subjects of importance to the Army such as combustion control and multiphase fluid dynamics. Random free stream velocities and boundary conditions will be incorporated in to the deterministic aerodynamic code developed by the principal investigator for supersonic cones at angle of attack and also in the a new code to be developed for the stochastic transonic small disturbance equation to gain further insights in to the theoretical work. A unique aspect of this research is the close interactions and connections.

Interest in periodic cellular metals has been driven by the structural and thermal management application potential of cellular metal sandwich structures. The research conducted in this program has led to the development of lattice structures which can be configured in the form of various core topologies of sandwich panels with high specific stiffness and strengths amenable for use in multifunctional applications (e.g. thermal dissipation, ballistic resistance). The applications of these lattice structures have been paced by two synergistic developments: the emergence of a micromechanics based approach for topology design, and scalable methods for the affordable manufacture of optimal lattices from high performance engineering materials., The original document contains color images. All DTIC reproductions will be in black and white.

Certain types of structures and materials, such as engineered multi-scale systems and comminuted zones in failed ceramics, may be modeled using continuum theories incorporating additional kinematic degrees of freedom beyond the scope of classical continuum theories. If such material systems are to be subjected to high strain rate loads, such as those resulting from ballistic impact or blast, it will be necessary to develop models capable of describing transient stress wave propagation through these media. Such a model is formulated, solved, and applied to the impact between two bodies and to a two-layer bar or strip subjected to an instantaneously applied stress. Results from these examples suggest that the model parameters, and therefore constitutive properties and geometries, may be tuned to reduce and control the transmission of stress through these bodies., The original document contains color images. Published in International Journal of Solids and Structures, v46 p1218-1228, 2009.