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Articles 5491 - 5520 of 5697
Full-Text Articles in Engineering
A Guide For The Consideration Of Composite Material Impacts On Airframe Costs, Jeffrey L. Isom
A Guide For The Consideration Of Composite Material Impacts On Airframe Costs, Jeffrey L. Isom
Theses and Dissertations
This study provides a guide to cost analysts who must consider the impact of composite materials on airframe costs. A literature review was conducted to determine the availability of cost models which incorporate the effect of composites on cost. A number of models are available, but no individual model was found that is applicable for every situation. In order to provide a baseline upon which analysts can compare model results as well as provide guidance in selecting cost drivers, a Delphi survey was conducted. Questionnaire results indicate that composite weight (as a percentage of total weight), composite part complexity, percentage …
A Model For Estimating Aircraft Recoverable Spares Annual Costs, Phillip L. Redding
A Model For Estimating Aircraft Recoverable Spares Annual Costs, Phillip L. Redding
Theses and Dissertations
This thesis covers three objectives: (1) develop a background reference document concerning recoverable spares cost estimating; (2) evaluate a representative sample of existing spares cost models; and (3) use aircraft physical and performance characteristics to develop a model for estimating annual replenishment spares cost. A condemnations cost estimating relationship (CER) was developed first and then both a CER and spreadsheet generated factors which related condemnations to replenishment spares costs were developed. For the condemnations CER, only logarithmic transformations provided statistically acceptable results, and even these models exhibited wide prediction intervals due to large amount of variability in the CER databases …
An Evaluation Of Logistics Support For F-16 Aircraft Owned By Foreign Countries, Paul J. Lyons
An Evaluation Of Logistics Support For F-16 Aircraft Owned By Foreign Countries, Paul J. Lyons
Theses and Dissertations
The purpose of this thesis was to examine the logistics support provided by the United States Air Force (USAF) for F-16 aircraft owned by foreign countries. The research drew from historical trends and personal experiences to examine the ability of the U.S. to provide logistics support for F-16 aircraft owned by U.S. allies. The study found that timely, efficient support of FMS customers possessing F-16 aircraft does not appear to be a principal concern of the USAF logistics system. Complexity of processes, untimely responses, and failure to consider customer needs are common failings on the part of the USAF.
Study On In-Theater Maintenance Support For Poaf F-16, Rui J. Gomes
Study On In-Theater Maintenance Support For Poaf F-16, Rui J. Gomes
Theses and Dissertations
The purpose of this study was to evaluate the capacity to generate a desired level of sorties of the F-16 weapon system. This capacity depends on the maintenance concept and structure, that defines a specific level of in-theater resources available. The theater is intended to reflect Portuguese Air Force logistic operations planned for the F-16, with one operational base and a possible Centralized Intermediate Repair Facility (CIRF), not co-located. The TSAR simulation program and one USAF database was used to perform the evaluation were defined and compared. The study focused on the unscheduled maintenance tasks and repairable items, in particular …
Challenges To United States Tactical Air Force Aircraft Maintenance Personnel: Past, Present And Future, Barbara L. Harris
Challenges To United States Tactical Air Force Aircraft Maintenance Personnel: Past, Present And Future, Barbara L. Harris
Theses and Dissertations
This study assessed the challenges Tactical Air Force (TAF) aircraft maintenance personnel face as a result of the TAF reorganization. The goal was to provide aircraft maintenance managers a basis for evaluating and meeting those challenges. To accomplish this, emphasis was placed on documenting the concepts, events, and conditions which led to changes in military aircraft maintenance from the birth of aviation to the present. Current issues such as the proposed move to two-level maintenance and the formation of the TAF composite and Objective Wings were also addressed. Research was conducted through the review of available historical documents, complemented by …
Inaccurate Data Entry Into The Air Force Maintenance Data Collection System, Jon R. Determan
Inaccurate Data Entry Into The Air Force Maintenance Data Collection System, Jon R. Determan
Theses and Dissertations
This research investigated the data collection environment under the Core Automated Maintenance System (CAMS), a computerized information system used in the Air Force's aircraft maintenance complexes. The research measured maintenance personnel's perception of the nature, extent, and causes of data inaccuracies occurring in the CAMS data collection environment. The nature was differentiated as being either intentional or accidental. Maintenance personnel felt that difficulty in entering information into CAMS accounted for the largest percentage of intentional errors and that insufficient training on CAMS accounted for the largest percentage of accidental errors. A comparison of this research to the results of earlier …
An Evaluation Of The Implementation Of Two-Levels Of Maintenance At Strategic Air Command Intercontinental Ballistic Missile Bases, Alan H. Russell
An Evaluation Of The Implementation Of Two-Levels Of Maintenance At Strategic Air Command Intercontinental Ballistic Missile Bases, Alan H. Russell
Theses and Dissertations
As a result of the 1979 Defense Management Review, Headquarters, Strategic Air Command has initiated programs of alternative levels of maintenance in order to trim excess costs. This study investigates the suitability of the SAC program which changed selected base-level strategic missile maintenance tasks from three to two-levels of maintenance. Using an opinion oriented questionnaire, this research surveyed a sample of missile maintenance personnel on their perceptions of the SAC program which implemented an alternative to intermediate-level maintenance. Analysis of survey results show respondents tended to believe the SAC program has not added benefit to their mission effectiveness. Other studies …
An Exploratory Application Of Neural Networks To The Sortie Generation Forecasting Problem, James M. Dagg
An Exploratory Application Of Neural Networks To The Sortie Generation Forecasting Problem, James M. Dagg
Theses and Dissertations
This exploratory study assesses the accuracy of backpropagation neural networks in predicting sortie generations, given pre-specified levels of air base resources. Single hidden layer networks and two-way interaction regression metamodels were fitted to simulated data previously generated by way of a factional design for ten factors at two levels, and subsequently tested (cross-validated) via an independent testing sample. It was determined that regression metamodels were generally superior in predicting unseen cases, while their network counterparts exhibited far better goodness-of-fit characteristics. The research consistently emphasizes that goodness-of-fit in no way necessarily implies goodness-of-prediction, in that different non-equivalent statistical measures are required …
Development Of An Operationally-Oriented Measure Of Sustainability, Moira D. Williams
Development Of An Operationally-Oriented Measure Of Sustainability, Moira D. Williams
Theses and Dissertations
This thesis proposes a framework for evaluating sustainability in the Air Force and for determining an appropriate measure of effectiveness that is both meaningful in a military sense and useful in planning and programming decisions. Following a literature review of organizational performance measures and strategy formulation, Michael Porter's Competitive Analysis model for strategy selection was presented. This model was then used to evaluate case studies in which organizations faced strategic decisions and to suggest measures by which these organizations could determine their effectiveness. The model was then shown to be applicable to the Air Force, and recommendations on implementing such …
Desert Express: An Analysis On Improved Customer Service, Thomas C. Thalheim
Desert Express: An Analysis On Improved Customer Service, Thomas C. Thalheim
Theses and Dissertations
Operation Desert Shield/Storm provided an opportunity to test the planning for U.S. forces to operate in a low intensity conflict. Both operations provided the opportunity for the logistics community to observe how the support forces provided the required supplies to the forward combat forces. In response to customers' requests, the U.S. Transportation Command created Desert Express, a daily package express flight from Charleston, SC to Saudi Arabia. The research question addresses the how and why Desert Express came about. Additional investigative questions cover the following: mission objectives, planners' and customers' expectations, system performance, and implications on the Defense Transportation System. …
A Comparison Of The Air Force, Army, And Navy Test And Evaluation Reliability And Maintainability Data Base Systems, Donald L. Scantlan Jr.
A Comparison Of The Air Force, Army, And Navy Test And Evaluation Reliability And Maintainability Data Base Systems, Donald L. Scantlan Jr.
Theses and Dissertations
This study was conducted to create a single source document which could be used by test and evaluation personnel involved in joint programs for translating reliability and maintainability terms. The comparison begins by describing the forms, data elements, and data items, as collected by the Air Force's System Effectiveness Data System, the Army's Reliability, Availability, Maintainability Logistics System, and the Navy's Maintenance and Material Management, Maintenance Data System. The Findings paragraph is a stand-alone document which could serve as a translating dictionary for reliability and maintainability data elements between the different service's data systems. Upon the conclusion of this study, …
A Study Of Pilot Attitudes Regarding The Impact On Mission Effectiveness Of Using New Cockpit Automation Technologies To Replace The Navigator/Weapon System Officer/Electronic Warfare Officer, William K. Starr, Donald A. Welch
A Study Of Pilot Attitudes Regarding The Impact On Mission Effectiveness Of Using New Cockpit Automation Technologies To Replace The Navigator/Weapon System Officer/Electronic Warfare Officer, William K. Starr, Donald A. Welch
Theses and Dissertations
This study analyzed the self-reported survey responses of 404 Air Force pilots concerning their perceptions of using advanced cockpit technologies to replace the Navigator, Weapon System Officer, and Electronic Warfare Officer (Nav/WSO/EWO) and the impact of advanced cockpit technologies on combat mission effectiveness. The first objective of this study was to compare, by aircraft type, the mission effectiveness factors that are always critical and almost always critical to the success of a combat mission. The second objective was to examine, from the pilot's point of view, the Nav/WSO/EWO's contribution (NAVCRIT) to enhancing the combat mission effectiveness factors. The third objective …
Life Cycle Costs Of The C-130 Electrical Power System Upgrade, Theodore D. Seymour
Life Cycle Costs Of The C-130 Electrical Power System Upgrade, Theodore D. Seymour
Theses and Dissertations
This research investigated the life cycle costs of three alternative electrical power systems for a planned electrical system upgrade to the C-130 transport aircraft. Research identified the contractors as (1) Sundstrand, (2) Westinghouse, and (3) Leland. The literature review included discussions on the C-130, electrical power systems and the proposed alternatives, and the elements of life cycle cost analysis. In the discussion on supportability issues, this research evaluated changes in mission capable rates and the needed fleet size to perform the current mission. In estimating Operating and Support costs, this research used the analogy approach. Analogies were based on expert …
Efficient Aircrew Scheduling In An Operational Test And Evaluation Organization, Charles P. Modrich
Efficient Aircrew Scheduling In An Operational Test And Evaluation Organization, Charles P. Modrich
Theses and Dissertations
The original intent of this research was to locate or develop tools which would improve the efficiency of the aircrew scheduling process in the 4950 Test Wing. However, late in the research it became apparent that several factors observed by the researcher complicate the implementation of more efficient methods. Therefore, the focus of the research became the documentation of those factors. A case study methodology was used in answering the investigative questions. This was an exploratory study conducted in a field setting environment. Direct observation and the use of structural interviews with scheduling personnel were the methods of data collection. …
An Analysis Of Total Quality Management In Aeronautical Systems Division, Mark D. Caudle
An Analysis Of Total Quality Management In Aeronautical Systems Division, Mark D. Caudle
Theses and Dissertations
This study investigated the major schools of thought on various aspects of quality management and quality improvement. Areas covered included definitions of waste and quality, views on the cost of quality, tools and techniques used for quality improvement, and management philosophies and frameworks for continuous improvement. In addition, this study analyzed the structure and training content of the current Total Quality Management program at Aeronautical Systems Division (ASD). Pre- and post-test surveys on employee attitudes toward organizational effective were analyzed from the Advanced Cruise Missile System Program Office (SPO), the F-15 SPO, and the ASD Deputy Chief of Staff for …
Model Identification And Control System Design For The Lambda Unmanned Research Vehicle, Gerald A. Swift
Model Identification And Control System Design For The Lambda Unmanned Research Vehicle, Gerald A. Swift
Theses and Dissertations
Research for this thesis centered on the Lambda Unmanned Research Vehicle (URV), an asset of the Flight Dynamics Directorate, Wright Laboratory Patterson AFB. The following tasks were accomplished: (1) a linear, state-space, small perturbation model was developed for both the longitudinal and lateral directional dynamics of the vehicles, and (2) pitch rate roll rate, and yaw rate flight controllers were designed using classical and multivariable feedback methods. The parameters of the linear, state space, small perturbation model were estimated from actual flight test data. Digital Datcom was first used to estimate stability and control derivatives from the vehicle's geometry. Maximum …
A Microcomputer Program For Estimating Production Costs Of Injection Molded Plastic Structures, Kyle F. Byard
A Microcomputer Program For Estimating Production Costs Of Injection Molded Plastic Structures, Kyle F. Byard
Theses and Dissertations
The job of estimating the production costs of injection molded thermoplastic structures requires designers and analysts to produce detailed preliminary drawings and consult machinists with expertise in mold production. Interviews with injection molding experts produced a scale of part complexity and associated range of labor hours for mold production. This scale is incorporated into a cost estimating methodology which allows the analyst to estimate the cost of the structure without the aid of technicians. The resulting cost model for the injection molding process is then programmed into an interactive Pascal computer program for ease of use and documentation.
Higher-Order Thickness Expansions For Cylindrical Shells, Randy A. Smith
Higher-Order Thickness Expansions For Cylindrical Shells, Randy A. Smith
Theses and Dissertations
Eight variations of higher-order transverse shear deformation (HTSD) theory were developed for composite shells. Three attributes were varied to produce the eight variations. These attributes include the order of the thickness expansions used to approximate the shell shape factors and the assumed linear displacement field and the nonlinearity of transverse shear strain. Several cylindrical shell problems were investigated using SHELL, a finite- element code with a 36 degree of freedom cylindrical shell element. MACSYMA, a symbolic manipulation code, was used to formulate the element independent stiffness arrays for each variation of the theory. When all nonlinear strain- displacement terms for …
An Analysis Of Base Level Environmental Organizations, John F. Akers Jr.
An Analysis Of Base Level Environmental Organizations, John F. Akers Jr.
Theses and Dissertations
The purpose of this thesis was to try and determine if there was one type of environmental organization which was truly so much more effective than the others that all bases should have it, or if the decision of which type of environmental organization to have should be left entirely to the bases. In addition, I hoped to discover the advantages and disadvantages of each type of organizational structure. I feel that knowing these advantages and disadvantages will greatly aid those individuals making the decisions on environmental organizational structure. In completing this study I turned to the only place the …
The Operation Of Military Family Housing As A Business Enterprise. A Case Study At Langley Air Force Base, Virginia, Michael T. Ray
The Operation Of Military Family Housing As A Business Enterprise. A Case Study At Langley Air Force Base, Virginia, Michael T. Ray
Theses and Dissertations
The focus of this research was to determine the feasibility of operating Military Family Housing (MFH) as a business enterprise, based on rental income. A case study of the Langley AFB Military Family Housing operation during FY 90 was used to determine if housing allowances forfeited by residents of base housing would provide sufficient rental income for the annual operations, maintenance and capital improvement of the MFH assets. It further compared the descriptive data from Langley AFB, Virginia, to USAF averages to determine if the findings at Langley were generalizable across the Air Force. The case study showed that Basic …
Evaluation Of Managerial Challenges Created By Acceleration Of The Installation Restoration Program, Robert L. Vinson Iii
Evaluation Of Managerial Challenges Created By Acceleration Of The Installation Restoration Program, Robert L. Vinson Iii
Theses and Dissertations
This study investigates the distribution of managerial tasks related to the Installation Restoration Program (IRP). Initiated in 1986, the IRP is the DoD program to identify and clean-up hazardous waste sites. Study areas include current distribution of managerial tasks, changes in task distribution needed to accelerate the program, and potential resource constraints. Additionally, the study considers how acceleration of Army and Navy restoration programs could impact the Air Force IRP. The study reveals IRP management is heavily centralized at MAJCOM with most technical work being performed through contracts with service centers. Individual bases have little direct involvement in the program. …
Industrial Wastewater Management Practices In Air Force Logistics Command, Patrick J. Smith
Industrial Wastewater Management Practices In Air Force Logistics Command, Patrick J. Smith
Theses and Dissertations
The selection of a model plant was based upon criteria established by a review of current literature. The criteria were permit compliance, plant performance, and the adoption of pollution prevention as a corporate environmental philosophy. In this study, private sector firms were examined to identify the best industrial wastewater management practices using a Total Quality Management (TQM) tool called benchmarking. The data gathering process consisted a survey of water pollution control organizations, and a survey of benchmark candidates. The purpose of surveying water pollution control organizations was to objectively identify possible benchmark candidates. A questionnaire was then used to gather …
Applying The Theory Of Constraints To A Base Civil Engineering Operations Branch, Bryan K. Zachmeier
Applying The Theory Of Constraints To A Base Civil Engineering Operations Branch, Bryan K. Zachmeier
Theses and Dissertations
The purpose of this thesis is to introduce the Civil Engineering manager to the Theory of Constraints management philosophy and to show how to apply this process of ongoing improvement to the Operations Branch. One of the reasons for the success of Theory of Constraints in commercial firms is that it provides all levels of management the ability to find simple solutions for bridging the gap between local and global issues. This 'bridge' is built by clearly defining the goal of the organization and using performance measurements capable of predicting the effect of local decisions and actions on the goal. …
A Comparative Analysis Of Three Water Treatment Programs For Cooling Tower Systems, Jeffry W. Shea
A Comparative Analysis Of Three Water Treatment Programs For Cooling Tower Systems, Jeffry W. Shea
Theses and Dissertations
This study investigated the cost and effectiveness of three cooling tower water treatment programs. The programs studied were an acid program developed at WPAFB, a commercial solubilizer program manufactured by Lombardi, Inc, and a crystal modifier program developed by Dias, Inc. The experiment ran for 60 days at which time cost and effectiveness data were collected. Cost comparison was evaluated on the basis of tower performance in MBtu. The costs considered in this experiment were water costs, sewer costs, and chemical costs. All costs were recorded and totaled, then divided by the tower's performance. The effectiveness of each treatment method …
Impacts Of Biomonitoring Requirements On Dod Wastewater Treatment Facilities, James R. Brady
Impacts Of Biomonitoring Requirements On Dod Wastewater Treatment Facilities, James R. Brady
Theses and Dissertations
Legislative emphasis on reducing the toxicity of wastewater effluent has resulted in increasingly sophisticated methods of determining toxicity. The purpose of this research project is to assess the impacts on DoD wastewater treatment facilities of one new monitoring method, biomonitoring. Biomonitoring has impacted DoD wastewater treatment facilities, however not to the degree anticipated. For bases that have been impacted, cost of contracting the tests is the primary problem associated with biomonitoring. Many bases have not been impacted because wastewater reuse has negated the need for discharge permits, and the inherent monitoring requirements. Bases subject to biomonitoring should assess water reuse …
An Expert System Solution For The Quantitative Condition Assessment Of Electrical Distribution Systems In The United States Air Force, David O. Paine
An Expert System Solution For The Quantitative Condition Assessment Of Electrical Distribution Systems In The United States Air Force, David O. Paine
Theses and Dissertations
Faced with a rapidly decreasing budget, the Air Force is in need of a method to objectively evaluate its aging utility infrastructure assets. This objective evaluation could be used to compare similar facility infrastructure systems for identification of possible problem areas and prioritization of major repair projects. This thesis developed a component model which can be used to objectively evaluate a typical electrical distribution system. The Delphi process was used to gather expert opinions regarding three areas: (1) the critical components which should be included in the model, (2) the relative importance of each selected critical component, and (3) the …
Investigation Of Advanced Aircraft Performance Measures Of Merit Including New Agility Metrics, Bruce A. Fox
Investigation Of Advanced Aircraft Performance Measures Of Merit Including New Agility Metrics, Bruce A. Fox
Theses and Dissertations
Advanced aircraft performance measures of merit have been proposed and individually analyzed by various researchers. These metrics have been consolidated into a single computer code as part of this research effort. This code was used to study the relationships between the advanced metrics, aircraft design metrics and an aircraft's trajectory performance. The study found a linear relationship existed between the advanced metrics and the design metrics. This relationship was used to quantify the required levels of the advanced metrics which would give desired changes in trajectory performance. The results showed that advanced metrics could be applied only to very specific …
Analysis Of Department Of Defense Organic Depot Maintenance Capacity Management And Facility Utilization Factors, Marlies Dewoody
Analysis Of Department Of Defense Organic Depot Maintenance Capacity Management And Facility Utilization Factors, Marlies Dewoody
Theses and Dissertations
This study investigated the effects of mandated depot capacity utilization rates on throughput, inventory, and operating expense. The measures of merit analyzed were work in process inventories, leadtime, and throughput. Since the services do not use a common computer system to track/compute capacity data, a computer simulation provided the data used to meet the research objectives. The simulation modeled a serially interdependent system subject to statistical fluctuations. Variability in the system was reduced by reducing the spread around the processing time mean. Buffer inventories were placed in front of each process to protect the process from variability. Constrained systems were …
Determining Production Capability In Aircraft Maintenance: A Regression Analysis, Charles R. Jung
Determining Production Capability In Aircraft Maintenance: A Regression Analysis, Charles R. Jung
Theses and Dissertations
This research analyzed twenty-three maintenance constraint and three production output performance measures for nine SAC aircraft systems. SAS System for Elementary Statistical Analysis is used to analyze twenty-one months of ex post facto maintenance data. Correlation analysis is used to identify maintenance constraints that assist in explaining aircraft maintenance production capability. Forward stepwise regression is used to build predictive models of maintenance production capability for each of the nine aircraft systems. The twenty-three maintenance constraint measures are regressed against three productivity output measures: Mission Capable Rate, Total Not Mission Capable Supply Rate and Total Not Mission Capable Maintenance Rate. The …
An Analysis Of Measures Used To Evaluate The Air Force Critical Item Program, Robert R. Lee
An Analysis Of Measures Used To Evaluate The Air Force Critical Item Program, Robert R. Lee
Theses and Dissertations
The purpose of this study was to evaluate the potential of two measures, percent defects and cycle time, to measure the overall performance of the Air Force Critical Item Program (CIP). The need for such study was generated from the current absence of any measurement system available to evaluate the CIP. This research used these two measures with actual data, evaluated the correlation between aircraft availability and percent defects and cycle time, and analyzed management perceptions addressing the usefulness of these measures for field use. Performance of this analysis resulted in support for these measures by over two thirds of …