A Comparison of Nonlinear Algorithms to Prevent Pilot-Induced Oscillations Caused by Actuator Rate Limiting
Actuator rate limiting has contributed to Pilot-Induced Oscillations (PIO) on almost every new fly-by-wire aircraft. Actuator rate limiting affected aircraft handling qualities in two ways: it exposed the aircraft's unaugmented flight dynamics and shifted the phase between the pilot input and actuator output. Phase shifting was the primary cause of PIO due to rate limiting. Two proposed solutions both placed a flight control system filter between the pilot command and actuator input. The first, referred to as Feedback-with- Bypass (FWB) and developed by Dr. Lars Rundqwist of SAAB Aircraft, used a low-pass filter to add phase lead to the pilot command. The second, referred to as Derivative- Switching (DS) and developed by Dr. Brad Liebst and Capt. Mike Chapa of AFIT, used the first and second derivatives of the pilot's command to reverse the actuator output in phase with the pilot input during actuator rate limiting. The objective of this study was to compare the ability of these two flight control system filters to prevent PIO during actuator rate limiting, and the filters' effects on aircraft handling qualities.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
An Evaluation and Implementation Guide for Current Groundwater Mass Flux Measurement Practices
Contaminant mass flux is an important parameter needed for decision making at sites with contaminated groundwater. New and potentially better methods for measuring mass flux are emerging. This study looks at the conventional transect method (TM), and the newer passive flux meter (PFM), modified integral pump test (MIPT), and tandem circulating well (TCW) methods. In order to facilitate transfer and application of these innovative technologies, it is essential that potential technology users have access to credible information that addresses technology capabilities, limitations, and costs. This study provides such information on each of the methods by reviewing implementation practices and comparing the costs of applying the methods at 16 standardized "template" sites. The results of the analysis are consolidated into a decision tree that can be used to determine which measurement method would be most effective, from cost and performance standpoints, in meeting management objectives at a given site. The study found that, in general: (1) the point methods (i.e. the TM and PFM) were less expensive to use to characterize smaller areas of contamination while the pumping methods (the MIPT and TCW) would be more economical for larger areas, (2) the pumping methods are not capable of high resolution sampling, which may be required to characterize heterogeneous systems or to design remediations, and (3) when high resolution is required, the PFM is more economical then the TM. Finally, the study demonstrated that, arguably, test results of the newer methods indicate that their accuracy is as good as, or better than, the accuracy of the TM, the currently accepted method.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Flight Test and Handling Qualities Analysis of a Longitudinal Flight Control System Using Multiobjective Techniques
This thesis addresses the application of optimal, multiobjective control theory control theory to flight control design for the approach and landing phase of flight. Five flight control systems were designed using classical, H2, H?, and Mixed H2/H? methods. The MATLAB" MUTOOLS" and AFIT MXTOOLS toolboxes were used to produce the optimal, multiobjective designs. These designs were implemented for flight test on the Calspan VSS I Learjet, simulating the unstable longitudinal dynamics of an F-16 type aircraft. A limited handling qualities investigation was performed. Model following was used in the design phase to meet handling qualities specifications. The designs were successfully implemented and verified on the Calspan Learjet prior to flight test. An unmodeled aircraft mode was discovered just prior to flight test that made three of the designs slightly unstable. However, all of the designs achieved Level II or better Cooper-Harper handling qualities ratings for the landing tasks performed illustrating that the optimal multiobjective methods used can give acceptable or better handling qualities.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Development Document for Proposed Effluent Limitations Guidelines and Standards for Synthetic-Based Drilling Fluids and Other Non-Aqueous Drilling Fluids in the Oil and Gas Extraction Point Source Cat
The U.S. Environmental Protection Agency (EPA) was introduced on December 2, 1970 by President Richard Nixon. The agency is charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress. The EPA's struggle to protect health and the environment is seen through each of its official publications. These publications outline new policies, detail problems with enforcing laws, document the need for new legislation, and describe new tactics to use to solve these issues. This collection of publications ranges from historic documents to reports released in the new millennium, and features works like: Bicycle for a Better Environment, Health Effects of Increasing Sulfur Oxides Emissions Draft, and Women and Environmental Health.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Illustrations And Descriptions Of Telegraphic Apparatus
"Illustrations And Descriptions Of Telegraphic Apparatus" provides a detailed look at the technology of telegraphy, focusing on the apparatus used for transmitting messages across distances. This book offers insights into the ingenuity and innovation of early telecommunications. Authored by Astley C. Terry and William Finn, it presents a visual and descriptive guide to the telegraphic systems of its time.With detailed illustrations and thorough descriptions, the book will appeal to historians of technology, telecommunications enthusiasts, and anyone interested in the evolution of communication systems. It serves as a valuable resource for understanding the foundations of modern communication networks and the inventive spirit behind them.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Computational Modeling of the Dielectric Barrier Discharge Device for Aeronautical Applications
Dielectric Barrier Discharge (DBD) type devices, when used as plasma actuators, have shown significant promise for use in many aeronautical applications. Experimentally, DBD actuator devices have been shown to induce motion in initially still air, and to cause re-attachment of air flow over a wing surface at a high angle of attack. This thesis explores the numerical simulation of the DBD device in both a 1D and 2D environment. Using well established fluid equation techniques, along with the appropriate approximations for the regime under which these devices will be operating, computational results for various conditions and geometries are explored. In order to validate the code, results are compared to analytic or experimental data whenever possible, or matched with other similar numeric simulations to help establish the accuracy of the code. Solutions to Poisson's equation for the potential, electron and ion continuity equations, and the electron energy equation are solved semi-implicitly in a sequential manner.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
An Analysis of Aircraft Handling Quality Data Obtained From Boundary Avoidance Tracking Flight Test Techniques
Cooper-Harper ratings (CHRs) have been used to describe and compare aircraft handling qualities for over 40 years, but are by their very nature, subjective. The subjective and sometimes ambiguous results obtained from qualitative handling quality ratings are inconsistent with the rest of the flight test process, where quantifiable results followed by statistical analysis are the norm. This thesis presents a method for obtaining accurate and consistent flight test data that quantifies the handling qualities of a specific aircraft. The method is demonstrated using both pilot-in-the-loop simulations and flight tests with the NF-16D Variable-Stability In-Flight Simulator Test Aircraft (VISTA). Boundary Avoidance Tracking (BAT), introduced in 2004 by Mr. William Gray III, a test pilot at the US Air Force Test Pilot School (TPS), is used here to provide a novel approach for forcing an increase in pilot workload and tracking performance in order to assess an aircraft's handling qualities. By utilizing BAT with shrinking desired performance boundaries on a point tracking task, pilots are forced to their maximum performance (i.e. minimum error) on the tracking task.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Performance Capability of a Damaged Lighter-Than-Air Vehicle Operation in the Near Space Regime
This study investigates the ability of a high-altitude airship to maintain lift following the compromise of its lifting gas envelope. Accepted engineering principles are applied to develop a model that provides comparative analyses for airship depressurization alternatives following hull compromise. Specifically, maintaining lifting gas envelope overpressure to provide controllability in wind currents while sacrificing some buoyancy is compared with allowing envelope depressurization to occur with the goal of maintaining greater buoyancy as long as possible. The model provides insights to alternatives for recovering a damaged vehicle and its payload. In particular, the analysis demonstrates that maintaining the ability to navigate while forfeiting buoyancy can provide additional down-range maneuver capability. In some cases preserving the airship's hull overpressure for some period of time following compromise, vice allowing a slow depressurization to atmospheric equilibrium, extends the distance a damaged airship can sustain controlled navigation as much as eighty percent. However, the airship will forfeit nearly twenty percent of the altitude it would otherwise preserve by not forcing a constant hull overpressure.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
CFD Analysis of Experimental Wing and Winglet for FalconLAUNCH 8 and the ExFIT Program
Reusable launch vehicles have many benefits over their expendable counterparts. These benefits range from cost reductions to increased functionality of the vehicles. Further research is required in the development of the technology necessary for reusable launch vehicles to come to fruition. The Air Force Institute of Technology's future involvement in the ExFIT program will entail designing and testing of a new wing tip mounted vertical stabilizer in the hypersonic regime. One proposed venue for experimentation is to utilize the United States Air Force Academy's FalconLAUNCH Program which annually designs, builds, and launches a sounding rocket capable of reaching hypersonic speeds. In the Spring of 2010 an experimental wing geometry will be flown on FalconLAUNCH VIII for the ExFIT Program. The following study outlines the Computational Fluid Dynamics analysis used to determine lift and drag characteristics as well as temperature distributions of the wing geometry before testing to produce a successful launch. A majority of this analysis focused on the effects caused by shock waves forming on the winglet and their impact on the lifting characteristics and temperature distribution of the wing. Ultimately a recommendation of a 3o angle of attack is given for the experimental wings on the rocket. At this configuration the lift and drag generated by the experimental wings will be at a minimum allowing for greater stability and speed throughout the flight of the rocket.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Characterizing the Exhaust Plume of the Three-Electrode Micro Pulsed Plasma Thrusters
Three-electrode micro-PPTs are a new version of two electrode micro-PPTs devices. Performance predictions and contamination expectations are essential characteristics needed by satellite designers. In order to focus on thruster specific impulse, thrust and efficiency, measuring the exhaust velocity or impulse bit and propellant consumption rate is essential. While this is not always possible to measure directly, focusing on the ejected mass from the PPT provides significant information allowing determination of these performance statistics. Specifically, focusing on exhaust angle distribution and velocity of the exhaust particles is the emphasis of this work. The results show that the three-electrode micro-PPT is more reliable than two-electrode micro-PPT and the operating energy range from 2 to 4.5 Joule is proper value to operate it. This research also shows that the angle distribution is similar to previous mass deposition distributions and the faster particles have shallower angles than that of slower particles. Finally, the energy did not give appreciable effect on angle and velocity distributions and have the Isp value range from 25 to 36 sec from the average exit velocity.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Medical Devices, Supporting Networks, and Their Vulnerabilities
With the implementation of "one Air Force, one network" under way it is important to look at how the Air Force plans to incorporate the medical field and its unique systems, networks, and mission. The medical field presents distinctive problems not seen in other areas. Open network vulnerabilities in the medical information systems not only pose a problem for the individual, but to the military service also. Possible security holes provide both access to vital military and personal information (end strength numbers, current status of personnel, social security), and a door way into the "network". Intruders now can possibly access command and control systems and other weapon systems. This research provides insight into the current and future information initiatives dealing with the Air Force's medical field and the Department of Defense's approach to system security. This research additionally looks at the laws and regulations dealing with privacy and ethical issues. This purview starts with the recently enacted Healthcare Insurance Portability and Accountability ACT (HIPPA), and concludes with the Laws of Armed Conflict. The research questions were answered through the use of a Case Study and a comprehensive literature review. The medical and network support teams from two Air Force medical facilities were the basis of this study.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Analysis of Bacterial Population and Distribution in the Developing Strata of a Constructed Wetland Used for Chlorinated Ethene Bioremediation
Chlorinated hydrocarbons and their degradation products are among of the most common organic groundwater contaminates in the United States. These compounds attack the central nervous system in animals and can affect the photosynthesis of plants. These compounds are also resistant to degradation in the environment and, because of this, pose a risk to any ecosystem in which they are present. This study identified the dominant microbial species in a constructed treatment wetland at Wright-Patterson AFB, Dayton, Ohio using 16S rRNA gene sequence analysis. Samples were taken from three different depths and during each of the four seasons. These samples were compared with similar samples taken from an uncontaminated, control site located at Valle Greene wetland in Beavercreek, Ohio. The intent of the study was to measure differences between the microbial community of the treatment wetland and the control wetland. It was hypothesized that the bacteria found to degrade the materials in the lab would be present in the treatment wetland and has a higher population than a wetland free of contaminants. This hypothesis would help support the idea that the natural attenuation of chlorinated hydrocarbons is due primarily to biological factors.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Modern Airships
Modern airships by design are capable of short-take off and landings (STOL), and vertical take-off and landings (VTOL). This VTOL capability enables the airship to land practically anywhere, independent of most infrastructure support. This ability would allow deploying heavy forces to be picked up at their home-station and transported directly to a location directed by the Combatant Commander, bypassing the labor intensive and time consuming portions of the deployment process. The challenge facing DoD is determining if this type of transport is feasible and acceptable for military use. DoD has already sponsored two studies on two very different airship designs, thus demonstrating DoD is interested in the airship heavy transport concept. This monograph highlights some of the findings from those studies and looks at historically proven uses of airships and some contemporary uses as well. Contemporary transports, the deployment process, and the associated challenges for deployments are also discussed. Together this information is used to assess feasibility and acceptability of airships as heavy transports. This monograph concludes with a positive assessment for the airship and recommendations for how DoD should proceed toward the use of airships in the not too distant future.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Flapping Wing Micro Air Vehicle Wing Manufacture and Force Testing
Numerous wing manufacturing techniques have been developed by various universities for research on Flapping Wing Micro Air Vehicles. Minimal attention though is given to repeatability of wing aerodynamics and dynamic response, which is crucial to avoid asymmetric flapping. Thus the focus of this research becomes twofold. First, repeatable wing manufacturing techniques are developed to ensure flapping wings have similar aerodynamic and dynamic characteristics. For this purpose, four wing designs were selected to not only test the aerodynamics of the different designs, but to also validate manufacturing techniques. The various wing designs are assessed using two methods: dynamic and aerodynamic data. Dynamic data, specifically the wing's structural dynamic response, is measured using a 3D laser vibrometer. From this vibration data, the wings natural frequency modes can be determined which should correlate strongly within the various wing designs if the manufacturing techniques are repeatable. Next, using a piezoelectric flapping actuator, the four wing designs are flapped with force data collected. This data is then used to determine the aerodynamic characteristics of each wing. From the two methods of wing evaluation, it was found that the wings manufactured using a three-layer carbon layup showed greater structural dynamic modal repeatability as compared to one-layer carbon wings. Additionally, Wing Design 3 flapped with the most efficiency with a significantly higher lift to drag ratio as compared to the other wing designs. From this research, the wing manufacturing techniques are quantitatively shown to be repeatable while an optimal wing design based on the maximum lift-to-drag ratio is found which can be used for future research.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Optimized Dual Expander Aerospike Rocket
Research at the Air Force Institute of Technology (AFIT) focused on designing a cryogenic dual-expander aerospike nozzle (DEAN) upper stage rocket engine to produce 50,000 pounds-force (222.4 kilo-Newtons) vacuum thrust, 464 seconds of vacuum specific impulse and a thrust-to-weight ratio of 106.5. The use of dual expander cycles improves engine reliability, maximizes efficiency, and eliminates some catastrophic failure modes. An upper stage engine with an aerospike nozzle is shorter and lighter than an equivalent performing conventional bell nozzle upper stage engine. Previous research focused on first developing a feasible closed DEAN design model and secondly expanding the model to support parametric trade and optimization studies. The current research effort used previous research as a foundation to create a reliable system level modeling tool to estimate performance, engine weight, and geometry for the DEAN concept. The model incorporated the Numerical Propulsion System Simulation (NPSS璽„[) software by NASA, Two-Dimensional Kinetics '04 (TDK'04璽„[) by Software and Engineering Associates, Inc, and ModelCenterTM by Phoenix Integration. Research obtained a new DEAN design point meeting physical and reusability design constraints from model trade and optimization studies. The new design has a vacuum thrust and a thrust-to-weight ratio of 50,161 lbf (223.1 kN) and 142.2, respectively. Furthermore, the new design has a vacuum specific impulse of 430.6 seconds, failing to meet the vacuum specific impulse design goal by 33.4 seconds or 7.3%. The model used common metals, alloys, and ceramics to improve near-term anufacturability of the DEAN. Current research laid a pathway for further research to find the optimum DEAN design point meeting all the design goals including vacuum specific impulse.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Tailored Systems Architecture for Design of Space Science and Technology Missions Using DoDAF V2.0
The use of systems architecture, following a set of integrated descriptions from an architecture framework, has been well codified in Department of Defense acquisition and systems engineering. However, in the Space Science and Technology (S and T) community, this guidance and practice is not commonly adopted. This paper outlines an approach to leverage the changes made in DoD Architecture Framework 2.0 (DoDAF2.0), and the renewed emphasis on data and support to acquisition decision analysis. After decomposing the Space S and T design lifecycle into phases, design milestones and activities using process models, a set of DoDAF prescribed and Fit-for-Purpose views are constructed into a reference implementation of a system architecture. This approach attempts to make DoDAF2.0 more relevant and integrated with S and T missions and the decisions that are encountered.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Optimal Dynamic Soaring for Full Size Sailplanes
Dynamic soaring is a unique flying technique designed to allow air vehicles to extractenergy from horizontal wind shears. Dynamic soaring has been used by seabirds like theAlbatross to fly hundreds of kilometers a day across the ocean. Small hobby radio controlledsailplanes have also used this technique to achieve sustained speeds of over 200 miles per hourfrom just a simple hand toss. Dynamic soaring, however, has never before been studied for useon full size aircraft. The primary goal of this research was to prove or disprove the viability ofdynamic soaring for enhancing a full size aircraft's total energy by using a manned sailplane as ademonstration air vehicle. The results of this study will have a direct impact on the sport ofsoaring, as well as the design of the next generation of large, sailplane-like, robotic planetaryexplorers for the National Aeronautics and Space Administration (NASA).This research began with a point mass optimization study of an L-23 Super Blaniksailplane. The primary goal of this study was to develop and analyze optimal dynamic soaringtrajectories. A prototype 6 degrees of freedom (DOF) flight simulator was then developed. Thissimulator helped to validate the dynamic soaring aircraft equations of motion derived for thisresearch and built operational simulator development experience.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Characterizing and Controlling the Effects of Differential Drag on Satellite Formations
The ability to fly satellites in close formations represents a capability that could revolutionize the way satellite missions are designed in the future. This study examines three of the primary formation flying designs and characterizes the affect that an anomalous satellite with a slightly different cross-sectional area would have on the stability of the formation. Following the characterization of the effects, a controller is implemented to mitigate the cross-sectional area differences between the satellites. With the addition of a straightforward controller, small cross-sectional area differences can be mitigated and corrected such that the satellites will remain in close proximity and in some cases the formation will remain stable.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Spacecraft Charging at Geosynchronous Altitudes
Spacecraft charging threatens to disable spacecraft components and adversely impact any satellite function. Electrostatic charge, and especially discharge, can hinder the proper operation of, or destroy, spacecraft components, thereby rendering the spacecraft ineffective or inoperative (Prokopenko and Laframboise, 1980:4125). The level of charging is dependent on the particle energy (speed) distribution. Current spacecraft design and materials provide limited protection against the dangers of electrostatic discharge, and active measures such as beam emission are also employed. The goal of this thesis is to investigate the kappa distribution as an alternative to the Maxwellian distribution as a method of predicting the onset of significant spacecraft charging by extending the research of Lai and Della-Rose (2001). Their work demonstrated the existence of critical (electron) temperatures above which the onset of significant spacecraft charging occurs. Below this critical temperature, significant charging does not occur (Lai and Della-Rose, 2001:927). Space plasmas are known to exhibit non-Maxwellian distributions at high (> 10 keV) energies (Vasyliunas, 1968:2840), and this knowledge provides the motivation for extending the work of Lai and Della-Rose to the kappa distribution. Solving the current balance equation is central to this area of research. Data from Los Alamos National Laboratory scientific instruments onboard geosynchronous satellites were analyzed to determine the efficacy of the kappa approach. However, the results of this thesis suggest that the kappa distribution, though superior to the Maxwellian at modeling high-energy particles (electrons), may be no better at determining charging onset.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Flight Dynamic Response of HALE Aircraft to KC-135 Flowfield
This research effort examines the static affects of a KC-135 flowfield on a flexible winged Sensorcraft model. The KC-135 flowfield data is generated by a vortex lattice code and integrated into Sensorcraft model for analysis. Building on previous research, a refueling situation was modeled to note the effects of the Sensorcraft at varying locations within the flowfield. The Sensorcraft model was analyzed for both rigid and flexible wings as a means of comparision. Flowfield locations of interest were determined and trimmed conditions were computed for each flowfield location.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Modeling a Field Application of In Situ Bioremediation of Perchlorate-Contaminated Groundwater Using Horizontal Flow Treatment Wells
Perchlorate contaminated groundwater is rapidly becoming a significant environmental remediation issue for the Department of Defense. In this study, an existing numerical model that simulates the operation of a Horizontal Flow Treatment Well (HFTW) system to effect the in situ biodegradation of perchlorate through the addition of an electron donor is modified to include a submodel that describes bioclogging. Bioclogging restricts flow out of the HFTW due to the accumulation of biomass directly adjacent to the well. The modified model is then applied to an existing perchlorate contaminated site that will be used for an evaluation of the HFTW technology. Simulations were conducted to determine the impact of altering various engineered parameters on HFTW performance. Simulation results indicate that higher time averaged electron donor concentrations and HFTW pumping rates lead to more perchlorate degradation in terms of total mass of perchlorate removed.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Impact of Parameter Accuracy on Aircraft Structural Integrity Estimates
The USAF initiated the Aircraft Structural Integrity Program (ASIP) over 40 years ago because of catastrophic, unanticipated, in-flight fatigue failures of in-service aircraft. In essence, ASIP is the management tool for the USAF to safely manage the fleet from initial operating capability through the design service goal and beyond. Since ASIP's inception, the USAF has not had a single catastrophic structural failure. The primary analysis tool to determine the fatigue life of a structural component in ASIP is linear elastic fracture mechanics (LEFM). In this effort, nine LEFM parameters were identified that affect the fatigue life: initial flaw assumption, boundary correction factor, load interaction models, crack growth rate data, stress intensity factor, threshold stress intensity factor, yield stress, and critical stress intensity factor.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
AMC's Hydrogen Future
The purpose of this research is to compare the costs associated with the transition to hydrogen aircraft for Air Mobility Command (AMC) to the costs of continuing using JP-8. Using current technology, air mobility aircraft can be designed to use liquid hydrogen instead of JP-8. This transformation will be capital intensive. A model was built that converted current AMC JP-8 usage to liquid hydrogen usage and calculated the costs of the infrastructure for that transition.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Cooperative Unmanned Aerial Surveillance Control System Architecture
Intelligence, surveillance and reconnaissance (ISR) is a high-demand Department of Defense mission performed by unmanned aircraft systems (UAS) at the tactical and theater levels. Coordinating UAS aircraft through cooperative control offers the advantages of persistence, distributed and adaptable sensor coverage, and reduced revisit time on points of interest. The purpose of this thesis is to apply systems engineering principals to the problem of developing a flexible, common control system for cooperative UAS surveillance at the tactical level. The AFIT team developed a concept of operations (CONOPS) encompassing various users and surveillance tasks. The team then used the scenarios in the CONOPS to build a conceptual architecture.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Multimission Aircraft Design Study, Payload
It is proposed that a Multi-Mission Aircraft (MMA) be prepared to combine some or all the functions of the aging AWACS, JSTARS, RIVET JOINT, COMPASS CALL, and ABCCC fleet. Three different thesis studies have been developed by three Air Force Institute of Technology GSE students to show the feasibility of replacing the current aging fleet with one or more MMA platforms. This is the thesis in which the payload issues have been examined. Within this thesis, two different alternative architectures, which are One Tail Number and Different Tail Numbers including nine different configurations, have been considered. Estimated payload characteristics of these alternatives have been compared to those of Boeing 767-400ER, which is the aircraft selected as the baseline for MMA platform. Reduced life cycle cost, increased measure of aircraft specifications, and minimum risk are the main objectives pursued by means of several systems engineering and aircraft design methodologies.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Using Statistical Process Control Methods to Classify Pilot Mental Workload
The problem of classifying pilot mental workload is important to the United States Air Force. Pilots are more subject to errors and G-induced loss of consciousness during periods of mental overload and task saturation. Often the result is the loss of aircraft, and in extreme cases, the loss of the pilot's life. Current research efforts use different psychophysiological features to classify pilot mental workload. These include cardiac, ocular, respiratory, and brain activity measures. The focus of this effort is to apply statistical process control methodology on different psychophysiological features in an attempt to classify pilot mental workload. The control charts track these features throughout the flight, and classify a segment as high workload if the measurements of these features are greater than predefined control limits. We find that certain control charts prove to be effective workload classifiers and maintain high classification accuracies when applied to other flight data.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Closely Supervised Reactive Control of an Uninhabited Aerial Vehicle
Currently, control of an uninhabited aerial vehicle (UAV) in flight is accomplished by manual control of a prior prescription of waypoints. The use of waypoints requires knowledge of vehicle position from either an Internal Navigation System (INS) or by using the Global Positioning System (GPS). This thesis proposes an alternative control method that incorporates some of the beneficial aspect of both fully manual and fully autonomous operation. Utilizing an on-board camera, an operator can control an uninhabited aerial vehicle by manually choosing desired targets of interest. The flight path of the uninhabited vehicle is determined autonomously from the camera gimbal angles. Specifically, the camera azimuth angle and elevation angle are transformed by an autopilot, providing commands to the aircraft. In this shared control operation, the operator of the payload (i.e. camera), has close supervision of the aircraft.The aircraft using an on-board computer is given autonomous control of aircraft flight, reducing personnel requirements.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Chromate Content Bias Versus Overspray Particle Size in Three Aircraft Primer Paints
The United States Air Force relies on the corrosion inhibiting properties of chromate-containing primer paints to protect the aluminum skin of its aircraft. Hexavalent chromium (Cr6+)--the ingredient responsible for the corrosion inhibiting characteristics of these primers--is a known human carcinogen. The concentration of Cr6+ in different particle sizes of paint overspray is important to understand health implications to painters as well as filtration efficiency. Previous research indicates disproportionately less Cr6+ content in smaller particles collected in the overspray of solvent-based epoxy-polyamide paint primers (MIL-P-2377G). This research explores the possibility of a particle size bias in the Cr6+ content of three commonly used aircraft primers: solvent-based epoxy-polyamide, water-based epoxy-polyamide (MIL-PRF-85582C), and solvent-based polyurethane (TT-P-2760A).This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
A Comparative Analysis of Singe-State-to-Orbit Rocket and Air-Breathing Vehicles
This study compares and contrasts the performance of a variety of rocket and airbreathing, single-stage-to-orbit, reusable launch vehicles. Fuels considered include bi-propellant and tri-propellant combinations of hydrogen and hydrocarbon fuels. Astrox Corporation's HySIDE code was used to model the vehicles and predict their characteristics and performance. Vehicle empty mass, wetted area and growth rates were used as figures of merit to predict the total cost trends of a vehicle system as well as the system's practicality. Results were compared to those of two-stage-to-orbit reusable launch systems using similar modeling methods. The study found that single-stage-to-orbit vehicles using scramjet airbreathing propulsion outperform rocket systems. Findings also demonstrate the benefits of using hydrocarbon fuel in the early phases of ascent to reduce the size and mass of launch vehicles.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Manufacturing and Evaluation of a Biologically Inspired Engineered MAV Wing Compared to the Manduca Sexta Wing Under Simulated Flapping Conditions
In recent years, researchers have expressed a vested interest in the concepts surrounding flapping wing micro air vehicles(FWMAVs) that are capable of both range and complex maneuvering. Most research in this arena has found itself concentrated on topics such as flapping dynamics and the associated fluid-structure interactions inherent in the motion, however there still remains myriad questions concerning the structural qualities intrinsic to the wings themselves. Using nature as the template for design, FWMAV wings were constructed using carbon fiber and Kapton and tested under simplifled flapping conditions by analyzing `frozen' digital images of the deformed wing by methods of photogrammetry.This flapping motion was achieved via the design and construction of a flapper that emulates several of the kinematic features that can be seen in naturally occurring flyers. The response to this motion was then compared to the inspiring specimen's wings, the North American Hawkmoth (Manduca Sexta), under the same flapping conditions in order to identify some of the key features that nature has deemed necessary for successful flight.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
An Evaluation of Formic Acid as an Electron Donor For Palladium Catalyzed Destruction of Nitroaromatic Compounds
The Department of Defense is responsible for over 2,000 hazardous waste sites containing nitroaromatic compounds (NACs) such as 2,4,6-TNT, 2,4- and 2,6-DNT that resulted from the production and use of munitions throughout the nation and world. NACs are typically persistent in natural environments, though they can be oxidized or reduced under engineered conditions. NACs and their reduction products are toxic chemicals and suspected human carcinogens. Both TNT and 2,4-DNT are listed as priority pollutants by the U.S. EPA. This study investigates the effectiveness of using a palladium (Pd) catalyst in concert with formic acid as an electron donor to reduce NACs. If the reduction reaction is rapid and complete, without producing hazardous daughter products, the process may have application as an in situ treatment technology to remediate NAC-contaminated groundwater. In this study, formic acid was added into NAC-contaminated water flowing through a laboratory column filled with Pd catalyst. Experimental results using 2,4-DNT as a model NAC indicate reduction rates are dependent on pH, formic acid concentrations, and NAC concentrations.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Application of Functionally Graded Materials in Aircraft Structures
A Functionally Graded Material (FGM) is a material which has a continuous variation of material properties through-the-thickness. This thesis will explore analysis of FGM flat plates and shell panels, and use FGM's unique characteristics to retrofit a cracked exhaust wash structure. FGMs are first characterized as flat plates under pressure and thermal loading. Next, FGM shell panels are characterized under thermal loading. Conclusions drawn from FGM characterization are used to develop a patch to retrofit a cracked aircraft exhaust wash structure. The exhaust wash structure is first analyzed to provide a baseline and then several FGM patches are evaluated on their ability to reduce stress and deflection. Finally, an exhaust wash panel made of FGM is analyzed.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Optimal Re-Entry Trajectory Terminal State Due to Variations in Waypoint Locations
The Air Force's Prompt Global Reach concept describes the desire to have a capability to reach any target within a 9000 nautical mile radius within two hours of launch. To meet this objective, much effort is being devoted to hypersonics and re-entry vehicles. Given the limited maneuverability of hypersonic vehicles, computational modeling is used to generate trajectories before launch to strike intended targets. In addition to endpoint (target) constraints, additional waypoints may constrain the trajectory. This research finds the optimal trajectory which satisfies the endpoint and waypoint constraints, and then investigates where else the vehicle can go while still meeting the mission objectives and the penalty for making such maneuvers. The result of this research is a direct numerical solution technique for mapping the sensitivity of the terminal state as a function of additional waypoint location. Multiple cases are presented including a simple endpoint-to-endpoint scenario and a waypoint included scenario, with a Gauss pseudospectral solver as the direct numerical solver.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Waste Vegetable Oil as an Alternative Fuel for Diesel Vehicles
Alternative fuels have become a hot topic in the news as the cost of oil remains volatile. Questions of whether acquiring alternative fuels are worth the cost, logistics, and political implications are being asked. A possible solution may be currently thrown away by Wright Patterson Air Force Base's (WPAFB) dining establishments in the form of waste vegetable oil (WVO). This study investigated the benefits and costs of pursuing the installation of a WVO to Straight Vegetable Oil fuel processing center and using the fuel to power some of the base's diesel vehicles. A pilot program was fielded utilizing the Wright Patterson Club for WVO and the Recycling Center for processing and use. From the pilot program, data was extrapolated to determine the total cost and payback period to operate the system. The benefits of reducing spills and emissions were also realized.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Experimental Methods to Characterize Nonlinear Vibration of Flapping Wing Micro Air Vehicles
For urban combat reconnaissance, the flapping wing micro air vehicle concept is ideal because of its low speed and miniature size, which are both conducive to indoor operations. The focus of this research is the development of experimental methods best suited for the vibration testing of the wing structure of a flapping wing micro air vehicle. This study utilizes the similarity of a beam resonating at its first bending mode to actual wing flapping motion. While computational finite element analysis based on linear vibration theory is employed for preliminary beam sizing, an emphasis is placed on experimental measurement of the nonlinear vibration characteristics introduced as a result of large movement. Beam specimens fabricated from 2024-T3 aluminum alloy and IM7/5250-4 carbon epoxy were examined using a high speed optical system and a scanning laser vibrometer configured in both three and one dimensions, respectively.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Organic Army Unmanned Aircraft Systems
Although Unmanned Aircraft Systems (UASs) are proliferating in the joint operational environment at an astonishing rate, they are meeting only a fraction of the demand. The USAF's failure to meet this insatiable demand for armed intelligence, surveillance, and reconnaissance (ISR) caused the Army to develop their own "organic" UAS capability. Does it make sense to spend $1.02B to create an aircraft capable of ranging the entire joint operations area, yet control it at the Army division level? This paper argues it is not in the best interest of the joint fight and it recommends alternative solutions for the Army's integration of "theater-capable" UASs. The research paper analyzes five contentious issues in a problem-solution format based on the USAF's MQ-1B Predator and the Army's planned MQ-1C Sky Warrior unmanned systems. The five issues include centralized versus organic control, rated pilots versus operators, airspace control methods, service interdependence, and deployment footprint. This research paper paints a picture of the current environment by looking at the situation from both the USAF and Army perspectives. This situation is not conducive to effective joint operations, and it will continue to deteriorate as the Army brings high altitude UASs online. This paper finds that the Army's decentralized, low altitude system composed primarily of rotary-wing assets historically coexisted underneath the Air Force's centrally controlled fixed-wing system. But the addition of more capable UASs, like Sky Warrior, brought the Army system up into the USAF system--where the two systems are no longer capable of providing an environment conducive to joint operations.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Whole Spacecraft Vibration Isolation
The Department of Defense has identified launch vibration isolation as a major research interest. Reducing the loads a satellite experiences during launch will greatly enhance the reliability, lifetime, and payload to structure ratio. DoD satellite programs stand to benefit significantly from advances in vibration isolation technology. This study explores potential hybrid vibration isolation control designs versus passive designs. A simple lumped mass dynamic model of a satellite and a representative launch vehicle was designed using Simulink. The analysis focuses on the various sources of transient launch accelerations such as aero-acoustic loads, separation events, wind gusts, and motor induced vibration. The passive vibration suppression design reduced axial "bounce" modes. Further reductions were made possible with an added active controller. The results of modeling indicate that as much as a 90 percent improvement in loads on the satellite were recognized from the combination of active and passive vibration control techniques. The model also explored the response of a sub-component of the satellite payload. For passive isolation the sub-component remained near its low baseline level of response, but for hybrid isolation the sub-component is exposed to greater levels of loading as a function of passive isolation frequency.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Critical Technologies for Building the Space Elevator
Into Space Using a Thread and a Laser - Blue DartWhat did the world think when Sputnik was launched? The United States clearly thought it needed to take up the challenge. Twelve years later, when Neil Armstrong set foot on the moon the world was breathless. That sort of imagination and hard work combined to make the United States' space program the premier exploration effort of the 20th century. The next great impossible task is to make space access affordable. Building a space elevator will generate the largest improvement in cost and capacity of any new space access technology. Space exploration is now a second rate topic. The media is more interested in stories about Britney Spears' latest folly or in reporting how many casualties occurred in Iraq or Afghanistan today. What will it take to reignite the public thirst for space exploration that everyone felt in 1969? Unfortunately the reasons for scaling back space exploration are too easy. It's too expensive. It doesn't offer enough benefits. It's a waste of time. Most reasons have their roots in the difficulty of getting to space in the first place. To cap it off, rockets are horribly inefficient in terms of fuel and weight. About 95% of what is on the launch pad is spent accelerating the remaining 5% into orbit. Subtract the structure of the rocket, and you can put a payload of 1-2% of launch weight into orbit. All that fuel costs a lot of money and rocket reusability has never been cheap or easy. A much more efficient concept is to have a tether stretching from the Earth out into space that electric vehicles climb and descend.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Cycle Performance of a Pulse Detontation Engine With Supercritical Fuel Injection
Pulse detonation engines (PDE) rely on rapid ignition and formation of detonation waves. Because hydrocarbon fuels are composed typically of long carbon chains that must be reduced in the combustion process, it would be beneficial to create such reduction prior to injection of fuel into the engine. This study focused on PDE operation enhancements using dual detonation tube, concentric-counter-flow heat exchangers to elevate the fuel temperature up to supercritical temperatures. Variation of several operating parameters included fuel type (JP-8, JP-7, JP-10, RP-1, JP-900, and S-8), ignition delay, frequency, internal spiral length, and purge fraction.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Should the Air Force Consider Investments in Renewable Energy a Weapon System?
The world is faced with an energy supply and demand challenge that greatly impacts the U.S. Air Force's ability to organize, equip, and train for today and tomorrow's war. For several decades the United States and its military became accustomed to relatively steady and cheap energy based upon petroleum. That model has been shattered during the past 5 years as a barrel of oil approached and passed an all time high of $112/barrel. The Air Force spent over $1.1 billion to operate its 166 installations in 2006. This paper looks at renewable energy sources such as solar, wind, and geothermal technology available today that could potentially reduce the cost of operating each base. These renewable sources of energy could also stabilize base operating costs so they don't fluctuate with each change of the world oil market.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Suppression of Pilot-Induced Oscillation
The purpose of this simulation study and flight test was to attempt to eliminate oscillatory departures and/or pilot-induced oscillations (PIOs) by means of selectively attenuating pilot command in the oscillatory frequency range. While rate limiting is a major contributor to many PIOs, this study examined both rate limiting and system time delay PIO events. A more broad approach to eliminating oscillatory departures and PIOs will assist pilots in maintaining aircraft control and therefore save both lives and aircraft. This simulation study was conducted at the Air Force Institute of Technology (AFIT), Wright-Patterson AFB, Ohio, and at the United States Air Force Test Pilot School (USAF TPS), Edwards AFB, California. The flight test project was flown in the USAF NF-16D Variable Stability In-flight Simulator Test Aircraft (VISTA) aircraft (S/N 86-0048) at Edwards AFB, CA. This aircraft was maintained and operated by the Veridian Engineering, Flight Research Group, Buffalo, New York.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
China's Space Program and Its Implications for the United States
China became a serious member of the spacefaring community in 1985 and in response, the U.S. developed agreements to limit the economic impact on U.S. space programs and to control the spread of related technology. China charges less for a space launch than a U.S. firm does and so an economic threat to the livelihood of U.S. space industries exists. The precarious U.S. launch industry is already challenged by Arianespace. The U.S. is also concerned about transferring technology to China from U.S. satellite manufacturers. The technology involved in mating satellites to boosters, measuring stress on the satellite at launch, and the development of apogee kick motors is all transferable to missile technology and may aid China in its intercontinental ballistic missile programs. Not only has China been improving its own programs, it has also sold missiles and technologies to other countries such as Iran, Iraq, Pakistan, and India. To foster the growing relationship between China and the U.S., clear policies and agreements are needed that match our national security interests with economic reality.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Employment of Unmanned Aircraft Systems for Canadian Forces Anti-Submarine Warfare
Currently, more than 30 nations are developing or manufacturing more than 250 models of Unmanned Aircraft Systems (UAS). Dramatic increases in UAS platform performance and payload capacity in recent medium and high altitude, long-endurance designs permitted customers to add more systems and capabilities to their UAS design requirements. These advances resulted in UAS platform capabilities that meet or exceed legacy manned fixed wing Intelligence Surveillance and Reconnaissance (ISR) and maritime surveillance platform capabilities. Employment of Medium-Altitude, Long-Endurance (MALE) and High-Altitude, Long Endurance (HALE) UAS in the anti-submarine warfare (ASW) role is rapidly becoming feasible through emerging technologies and expanded payload capacities, the most significant of which are secure high-bandwidth Beyond Line of Sight (BLOS) satellite datalink communications, miniature light-weight sonobuoys, and real-time shore-based acoustic processing. As a result, UAS may be a technically feasible future Canadian Forces (CF) ASW capability as a complementary or stand-alone alternative to manned fixed-wing and rotary-wing maritime ASW platforms.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Characterization Of Chlorinated Solvent Degradation in a Constructed Wetland
Widespread chlorinated ethene contamination of aquifers coupled with high costs of current treatment technologies demand innovative remediation solutions. Wetlands, maintaining anaerobic and aerobic zones promoting the complete degradation of chlorinated ethenes such as Tetrachloroethylene (PCE), could be the answer. This thesis characterized the chlorinated solvent contamination levels in three strata of an upward flow constructed wetland. Analysis of samples was accomplished by purge-and-trap gas chromatography. Water quality parameters, Dissolved Oxygen (DO), Oxidation Reduction Potential (ORP), pH, Conductivity, and Temperature, were also measured in monitoring wells with a water monitoring sonde. After removing data outliers caused by short-circuiting flow, PCE concentrations declined from an average of 32.59 ?簣 0.699 ppb (?簣 95% confidence interval) in the inflow stream to an average of 0.171 ?簣 0.807 ppb in the upper layer (a 99.3% reduction).This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Analysis of Bacterial Population and Distribution in the Developing Strata of a Constructed Wetland Used for Chlorinated Ethene Bioremediation
Chlorinated hydrocarbons and their degradation products are among of the most common organic groundwater contaminates in the United States. These compounds attack the central nervous system in animals and can affect the photosynthesis of plants. These compounds are also resistant to degradation in the environment and, because of this, pose a risk to any ecosystem in which they are present. This study identified the dominant microbial species in a constructed treatment wetland at Wright-Patterson AFB, Dayton, Ohio using 16S rRNA gene sequence analysis. Samples were taken from three different depths and during each of the four seasons. These samples were compared with similar samples taken from an uncontaminated, control site located at Valle Greene wetland in Beavercreek, Ohio. The intent of the study was to measure differences between the microbial community of the treatment wetland and the control wetland. It was hypothesized that the bacteria found to degrade the materials in the lab would be present in the treatment wetland and has a higher population than a wetland free of contaminants. This hypothesis would help support the idea that the natural attenuation of chlorinated hydrocarbons is due primarily to biological factors.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Optimization of Hybrid-Electric Propulsion Systems for Small Remotely-Piloted Aircraft
Small electric-powered remotely-piloted aircraft (RPA) used by today's warfighters for intelligence, surveillance, and reconnaissance (ISR) missions lack desired endurance and loiter times, while the acoustics and thermal signatures of those configured with internal combustion engines (ICE) may make them unpractical for ISR. Outfitting RPA with parallel hybrid-electric propulsion systems (H-EPS) would meet the military's needs by combining the advantages of both systems while reducing fuel consumption and environmental impacts. An analysis tool was created, using constrained static optimization, to size the H-EPS components. Based on the RPA's required power and velocity for the endurance phase, an electric motor (EM) can be designed or selected and matched with a commercial off-the-shelf (COTS) propeller for maximum efficiency. The ICE is then sized for the RPA's required power and velocity for the cruise phase.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Optimal Dynamic Soaring for Full Size Sailplanes
Dynamic soaring is a unique flying technique designed to allow air vehicles to extractenergy from horizontal wind shears. Dynamic soaring has been used by seabirds like theAlbatross to fly hundreds of kilometers a day across the ocean. Small hobby radio controlledsailplanes have also used this technique to achieve sustained speeds of over 200 miles per hourfrom just a simple hand toss. Dynamic soaring, however, has never before been studied for useon full size aircraft. The primary goal of this research was to prove or disprove the viability ofdynamic soaring for enhancing a full size aircraft's total energy by using a manned sailplane as ademonstration air vehicle. The results of this study will have a direct impact on the sport ofsoaring, as well as the design of the next generation of large, sailplane-like, robotic planetaryexplorers for the National Aeronautics and Space Administration (NASA).This research began with a point mass optimization study of an L-23 Super Blaniksailplane. The primary goal of this study was to develop and analyze optimal dynamic soaringtrajectories. A prototype 6 degrees of freedom (DOF) flight simulator was then developed. Thissimulator helped to validate the dynamic soaring aircraft equations of motion derived for thisresearch and built operational simulator development experience.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
An Evaluation of Formic Acid as an Electron Donor For Palladium Catalyzed Destruction of Nitroaromatic Compounds
The Department of Defense is responsible for over 2,000 hazardous waste sites containing nitroaromatic compounds (NACs) such as 2,4,6-TNT, 2,4- and 2,6-DNT that resulted from the production and use of munitions throughout the nation and world. NACs are typically persistent in natural environments, though they can be oxidized or reduced under engineered conditions. NACs and their reduction products are toxic chemicals and suspected human carcinogens. Both TNT and 2,4-DNT are listed as priority pollutants by the U.S. EPA. This study investigates the effectiveness of using a palladium (Pd) catalyst in concert with formic acid as an electron donor to reduce NACs. If the reduction reaction is rapid and complete, without producing hazardous daughter products, the process may have application as an in situ treatment technology to remediate NAC-contaminated groundwater. In this study, formic acid was added into NAC-contaminated water flowing through a laboratory column filled with Pd catalyst. Experimental results using 2,4-DNT as a model NAC indicate reduction rates are dependent on pH, formic acid concentrations, and NAC concentrations.This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
