649 research outputs found

    Paper Session III-B - Space Exploration Initiative Logistics Support - Lessons from the DoD

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    A mission as complex as the Space Exploration Initiative (SEI) cannot succeed without adhering to sound principles in the planning, development, and execution of logistics support for the exploration crews and their mission equipment. While much attention will focus upon the development of reliable, robust, heavy lift launch vehicles, and scientific, technological breakthroughs for SEI, of equal concern is the supportability and sustainability of systems designed for mission operations and crew life support on the lunar and Martian surfaces

    Examining EXPRESS with Simulation

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    The Execution and Prioritization of Repair Support System (EXPRESS) is a database tool used by the Air Force to prioritize depot maintenance of reparable spare parts to maximize responsiveness to warfighter need. Many studies have examined individual portions of EXPRESS, though few have examined it as an entire system. This effort proposes a modeling approach for examining the overall system behavior of EXPRESS using discrete event simulation. The emphasis of the model is to be flexible enough to provide useful insight into system performance, while also remaining open-ended enough to provide a foundation for future expansion and analysis. A case study involving three reparable parts managed by EXPRESS, based on 6 months of real world data, focuses on total Mission Capability (MICAP) hours as a measure of responsiveness to customer need. The model is validated using data on actual MICAP hours for the modeled period. The case study simulation is then used to study the impact on responsiveness and repair behavior resulting from running EXPRESS less frequently. Output data points to increases in total MICAP hours and variance in repair workload as run frequency decreases. The conclusion is that running EXPRESS less frequently negatively impacts system performance for both the maintenance and warfighter communitie

    Examining the EXPRESS Supportability Module: Implementing an Autoregressive Distributed Lag Approach with Air Force Maintenance Data

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    Launched in 1996, EXPRESS (Execution and Prioritization of Repairs Support System) is a program integral to the Air Force reparable supply chain. Daily, EXPRESS relies on a number of data sources and individual modules like the Supportability Module to determine which necessary repairs can and should be made. The Supportability Module examines the prioritized list of repairs and checks four constraints in order to decide whether each repair can be made given current resources. According to the logic of the module, a single constraint failure means that subsequent resource checks are not made before evaluating the next repair. Unfortunately, this leads to missing observations in the EXPRESS data table, ultimately masking potential resource issues and possibly contributing to extended mission capability issues. In this study, a time series analysis via explanatory autoregressive distributed lag (ARDL) models was conducted using EXPRESS and MICAP (mission capability) data to examine possible connections between missing constraint values in the EXPRESS table and future MICAPs. These models suggested that up to 0.793 MICAP days are added for each additional parts failure missing in the EXPRESS table. Additionally, the presence of significant relationships between the EXPRESS and MICAP data over time suggest that maintainers examining trends in the EXPRESS data could feasibly reduce future MICAPs. As a byproduct of this study, the potential for the use of time series models with maintenance data was explored. Model diagnostics suggest that maintenance data is too volatile and noisy for regression-based methods and that stochastic methods or simulation may prove more useful

    Evaluation of the HARDMAN comparability methodology for manpower, personnel and training

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    The methodology evaluation and recommendation are part of an effort to improve Hardware versus Manpower (HARDMAN) methodology for projecting manpower, personnel, and training (MPT) to support new acquisition. Several different validity tests are employed to evaluate the methodology. The methodology conforms fairly well with both the MPT user needs and other accepted manpower modeling techniques. Audits of three completed HARDMAN applications reveal only a small number of potential problem areas compared to the total number of issues investigated. The reliability study results conform well with the problem areas uncovered through the audits. The results of the accuracy studies suggest that the manpower life-cycle cost component is only marginally sensitive to changes in other related cost variables. Even with some minor problems, the methodology seem sound and has good near term utility to the Army. Recommendations are provided to firm up the problem areas revealed through the evaluation

    Implication of FORCEnet on coalition forces

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    The coalition navies of Australia, Canada, New Zealand, United Kingdom and the United States (AUSCANNZUKUS) are in a period of transformation. They are stepping out of the Industrial Age of warfare and into the Informational Age of warfare. Network Centric Warfare (NCW) is the emerging theory to accomplish this undertaking. NCW describes "the combination of strategies, emerging tactics, techniques, and procedures, and organizations that a fully or even partially networked force can employ to create a decisive war fighting advantage." 1 This theory is turned into a concept through Network Centric Operations (NCO) and implemented through the FORCEnet operational construct and architectural framework. The coalition navies are moving in a direction to develop and leverage information more effectively and efficiently. This will lead to an informational advantage that can be used as a combat multiplier to shape and control the environment, so as to dissuade, deter, and decisively defeat any enemy. This analysis was comprised of defining three TTCP AG-6 provided vignettes into ARENA model that captured Coalition ESG configurations at various FORCEnet levels. The results of the analysis demonstrated that enhanced FORCEnet capabilities such as FORCEnet Levels 2 and 4 would satisfy the capability gap for a needed network-centric ESG force that can effectively counter insurgency operations in Maritime warfare. Furthermore, the participating allied navies in the Coalition ESG should pursue acquisition strategies to upgrade their ship platforms in accordance with our recommendation which indicates that FORCEnet Level 2 is the best value.http://archive.org/details/implicationoffor109456926N

    Quantification of Mandatory Sustainment Requirements

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    To emphasize the importance of sustainment, the DoD Joint Requirements Oversight Council addressed sustained Materiel readiness and established a mandatory Key Performance Parameter (KPP) for Materiel Availability; it also established supporting Key System Attributes (KSAs) for Materiel Reliability and Ownership Cost (Chairman of the Joint Chiefs of Staff Manual (CJCSM) 3170.01C, 2007). Current guidance requires two numbers: a threshold value and an objective value (Chairman of the Joint Chiefs of Staff Manual (CJCSM) 3170.01C, 2007). No distinction is made between the approaches in establishing these values for major system acquisitions, versus smaller, modification-focused efforts for existing systems. The Joint Staff proposed guidance to assist in determining these values for major acquisition programs, but the guidance has yet to be tested on modification contracts. To assess its applicability, we performed a case study of a recent acquisition program under consideration by Air Mobility Command. We sought to apply the principles put forth in this draft guide prepared by the Office of the Secretary of Defense in Collaboration with the Joint Staff. This research seeks to assist the combat developer and program manager to develop an objective, standard, repeatable method for quantifying the mandatory Materiel Availability KPP and the associated Materiel Reliability KSA values established by the Joint Requirements Oversight Council

    Foundations of Supply Chain Management for Space Application

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    Supply Chain Management (SCM) is a key piece of the framework for America's space technology investment as the National Aeronautics and Space Administration (NASA), the aerospace industry, and international partners embark on a bold new vision of human and robotic space exploration beyond Low-Earth-Orbit (LEO). This type of investment is driven by the Agency's need for cost efficient operational support associated with, processing and operating space vehicles and address many of the biggest operational challenge including extremely tight funding profiles, seamless program-to-program transition activities and the reduction of the time gap with human spaceflight capabilities in the post-Shuttle era. An investment of this magnitude is a multiyear task and must include new patterns of thought within the engineering community to respect the importance of SCM and the integration of the material and information flow. Experience within the Department of Defense and commercial sectors which has shown that support cost reductions and or avoidances of upwards to 35% over business as usual are achievable. It is SCM that will ultimately bring the solar system within the economic sphere of our society

    How Should Life Support Be Modeled and Simulated?

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    Why do most space life support research groups build and investigate large models for systems simulation? The need for them seems accepted, but are we asking the right questions and solving the real problems? The modeling results leave many questions unanswered. How then should space life support be modeled and simulated? Life support system research and development uses modeling and simulation to study dynamic behavior as part of systems engineering and analysis. It is used to size material flows and buffers and plan contingent operations. A DoD sponsored study used the systems engineering approach to define a set of best practices for modeling and simulation. These best practices describe a systems engineering process of developing and validating requirements, defining and analyzing the model concept, and designing and testing the model. Other general principles for modeling and simulation are presented. Some specific additional advice includes performing a static analysis before developing a dynamic simulation, applying the mass and energy conservation laws, modeling on the appropriate system level, using simplified subsystem representations, designing the model to solve a specific problem, and testing the model on several different problems. Modeling and simulation is necessary in life support design but many problems are outside its scope

    NASA Space Exploration Logistics Workshop Proceedings

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    As NASA has embarked on a new Vision for Space Exploration, there is new energy and focus around the area of manned space exploration. These activities encompass the design of new vehicles such as the Crew Exploration Vehicle (CEV) and Crew Launch Vehicle (CLV) and the identification of commercial opportunities for space transportation services, as well as continued operations of the Space Shuttle and the International Space Station. Reaching the Moon and eventually Mars with a mix of both robotic and human explorers for short term missions is a formidable challenge in itself. How to achieve this in a safe, efficient and long-term sustainable way is yet another question. The challenge is not only one of vehicle design, launch, and operations but also one of space logistics. Oftentimes, logistical issues are not given enough consideration upfront, in relation to the large share of operating budgets they consume. In this context, a group of 54 experts in space logistics met for a two-day workshop to discuss the following key questions: 1. What is the current state-of the art in space logistics, in terms of architectures, concepts, technologies as well as enabling processes? 2. What are the main challenges for space logistics for future human exploration of the Moon and Mars, at the intersection of engineering and space operations? 3. What lessons can be drawn from past successes and failures in human space flight logistics? 4. What lessons and connections do we see from terrestrial analogies as well as activities in other areas, such as U.S. military logistics? 5. What key advances are required to enable long-term success in the context of a future interplanetary supply chain? These proceedings summarize the outcomes of the workshop, reference particular presentations, panels and breakout sessions, and record specific observations that should help guide future efforts

    SIMULATING CONSUMABLE ORDER FULFILLMENT VIA ADDITIVE MANUFACTURING TECHNOLOGIES

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    Operational availability of naval aircraft through material readiness is critical to ensuring combat power. Supportability of aircraft is a crucial aspect of readiness, influenced by several factors including access to 9B Cognizance Code (COG) aviation consumable repair parts at various supply echelons. Rapidly evolving additive manufacturing (AM) technologies are transforming supply chain dynamics and the traditional aircraft supportability construct. As of June 2022, there are 595 AM assets within the Navy’s inventory—all for research and development purposes. This report simulates 9B COG aviation consumable fulfillment strategies within the U.S. Indo-Pacific sustainment network for a three-year span, inclusive of traditional supply support avenues and a developed set of user-variable capability inputs. Simulated probabilistic demand configurations are modeled from historical trends that exploit a heuristic methodology to assign a “printability” score to each 9B COG requirement, accounting for uncertainty, machine failure rates, and other continuous characteristics of the simulated orders. The results measure simulated lead time across diverse planning horizons in both current and varied operationalized AM sustainment network configurations. This research indicates a measurable lead time reduction of approximately 10% across all 9B order lead times when AM is employed as an order fulfillment source for only 0.5% of orders.NPS Naval Research ProgramThis project was funded in part by the NPS Naval Research Program.Lieutenant Commander, United States NavyApproved for public release. Distribution is unlimited
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