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ADDITIVE MANUFACTURING OF JACKET WATER PUMP IMPELLER FOR USCG CUTTER EMERGENCY DIESEL GENERATOR
Get PDFThis project aimed to reverse engineer an impeller for an obsolete, cast iron centrifugal jacket water pump currently operating on the U.S. Coast Guard’s (USCG) 270-foot cutters’ emergency diesel generators. This project’s scope represented the first phase in delivering a certifiable, working centrifugal pump comprised of an additively manufactured impeller in 316L stainless steel material. In producing this part, a global, certifiable process utilizing additive manufacturing and organic USCG and U.S. Navy resources was developed, first by analyzing the pump’s failure mechanisms, the impeller’s structure via ANSYS Mechanical software, and the pump assembly’s fluid flow via ANSYS CFX software. The U.S. Coast Guard-provided impeller design was then modified to facilitate the additive manufacturing and post-machining processes and provided to Protolabs, who subsequently produced and heat treated two new, to-scale 316L stainless steel impeller blanks and accompanying tensile specimen sets. An impeller blank was post-machined at NPS, which was a critical juncture in preparing for the next phase of this project. The finished impeller will be balanced and assembled with other provided and procured components, and then the assembled pump will be tested and compared to expected performance data. Upon the satisfactory test, a new viable spare pump will be delivered to the USCG for subsequent testing and then implementation on operational assets.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant, United States Coast GuardU.S. Coast GuardCAMR
ANALYZING THE HISTORICAL COMPLAINTS REGARDING HOUSEHOLD GOODS AND THE DEPARTMENT OF DEFENSE’S REMEDY
Get PDFThe frequent permanent change of station (PCS) that military members undergo every few years requires the movement of the members’ household goods. The Government Accountability Office, among other government entities, researched the movement of household goods and determined it needs more oversight by the Department of Defense (DOD). In response, the DOD approved a new contract to ensure better oversight of household goods for military members, which is in effect in 2024. This thesis systematically analyzed comments in the services’ trade publications to investigate if the current contract is likely to address customers’ concerns. The results show Gaps 1 and 2 are the most prevalent customer service gaps with moving goods in the PCS process. I recommend the DOD monitor the communication within the new system by utilizing customer feedback and monitor the upgraded technology behind the new claims process.Distribution Statement A. Approved for public release: Distribution is unlimited.Captain, United States Marine Corp
ADAPTIVE ACQUISITION FRAMEWORK: EFFECTIVENESS OF THE MIDDLE TIER OF ACQUISITION PATHWAY
Get PDFThe Adaptive Acquisition Framework (AAF) was created to provide the warfighter with innovative technologies and new capabilities at the speed of relevance. While the AAF has six pathways, the middle tier of acquisition (MTA) pathway focuses on delivering rapid capabilities through rapid prototyping or fielding. However, due to the pathway's infancy, how effective it is at delivering its objective needs to be clarified. This limited the research and analysis to MTA rapid prototyping (MTRP) as the primary focus. The initial metric to measure effectiveness was to conduct a statistical analysis of all completed MTRP programs from the Defense Acquisition Visibility Environment (DAVE) in a pass/fail capacity. Through hypothesis testing and a sample size of 55 programs, the findings concluded that the probability of a system being transitioned/restructured would fall between 71.2% (39/55) and 92.2% (50/55). Additionally, the analysis tried to form a correlation between programs reported on by the Government Accountability Office (GAO) and those found in DAVE to identify trends, factors, or inconsistencies that could influence success, but to no avail. However, DAVE proved ineffective at providing enough information to evaluate effectiveness at this level. It is recommended that a case study be performed against two programs of similar nature, one considered a success vs. a failure, to determine best practices for gauging effectiveness.Distribution Statement A. Approved for public release: Distribution is unlimited.Civilian, Department of the NavyCivilian, Department of the Nav
THE EFFECT OF TROPICAL CYCLONE PASSAGE ON UNDERSEA ACOUSTIC PARAMETERS IN THE EAST CHINA SEA
Get PDFThis research examines the impact of tropical cyclone passage on undersea acoustic parameters in the East China Sea using 222 historical tropical cyclone tracks and seven acoustic parameters from 1979 to 2010 (i.e., the global warming period). Data from the Fleet Numerical Meteorology and Oceanography Center’s Climate Forecast System Reanalysis ocean dataset and Joint Typhoon Warning Center’s Western North Pacific Ocean Best Track Data were analyzed. The acoustic parameters include in-layer gradient, surface duct cutoff frequency, sonic layer depth, below layer gradient, deep sound channel axis, deep sound channel strength, and critical depth. Results show that all acoustic parameters, with the exception of below layer gradient, experience a response to tropical cyclone passage that is correlated with storm intensity. Furthermore, the most significant anomalous acoustic response occurs in the summer months, and is most drastic with super typhoon passage. Ultimately, recognition of the effect of tropical cyclone passage on the water column will allow for more accurate ocean predictions, to include underwater acoustics, in an operationally relevant region.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant Commander, United States Nav
DECISION-MAKING ON STRATEGIES FOR LIFE EXTENSION OF SHIPS IN THE BRAZILIAN NAVY USING A TECHNO-ECONOMIC ANALYSIS APPROACH
Get PDFThis research presents a techno-economic methodology to support decision-making in extending the service life of ships in the Brazilian Navy. Addressing the dual challenge of operating an aging fleet within budgetary constraints, the proposed framework combines technical assessments with economic considerations. This integrated approach merges reliability principles and probability failure predictions to technically assess ship condition with a cost-benefit analysis to evaluate economic viability, ensuring decisions are both technically sound and economically justified. The potential of the proposed methodology is illustrated through a case study involving a ship within the Brazilian Navy fleet. Three life extension options (reuse, refurbishment and replacement) are analyzed based on available data. The findings recommend adopting the “reuse” strategy.Distribution Statement A. Approved for public release: Distribution is unlimited.Capitão de Corveta, Brazilian Nav
A COMPARATIVE ANALYSIS ON USING LOW EARTH ORBIT AND GEOSYNCHRONOUS ORBIT SATELLITE COMMUNICATION SYSTEMS TO SUPPORT TELEMEDICAL NETWORKS IN AUSTERE ENVIRONMENTS
Get PDFIn austere environments, satellite communication is the only practical option for telemedical backhaul. Supporting telemedical applications over low earth orbit (LEO) and geosynchronous orbit (GEO) satellite communications links requires a detailed analysis of how the characteristics of these links impact telemedical applications. This thesis aims to show if the characteristics of LEO or GEO satellite communications are better suited to support telemedicine in an austere environment. This is done by comparing the performance of medical application traffic over LEO, GEO, and terrestrial internet service provider links to show how different link characteristics impact network traffic. Terrestrial internet service provider links are used as a baseline for comparison because most applications perform optimally on high-speed terrestrial communication links. The analysis uses objective data to show that non-interactive and non-delay tolerant applications perform better on a GEO link, while interactive non-delay tolerant, interactive delay-tolerant traffic, and non-interactive delay tolerant traffic all perform better on LEO links. This work reveals that the protocol stack for telemedical applications can be selected or designed to optimize performance over LEO satellite communication links, but GEO links add latency impacts to interactive communication that cannot be mitigated.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant Commander, United States Navy711 HPW/FMUS, Wright-Patterson AFB, OH 4543
A COMPARISON OF SUCCESS RATES IN NAVAL AIR TRAINING BETWEEN STUDENTS WITH AND WITHOUT PRIOR FLIGHT EXPERIENCE
Get PDFTo help ensure that Naval Air Training is efficiently producing pilots capable of meeting the needs of the U.S. Navy, Marine Corps, and Coast Guard, we conduct a statistical analysis on Student Naval Aviators with prior civilian flight experience in comparison to those who do not have any prior flight experience. Some Student Naval Aviators have received pilot training prior to reporting to Naval Air Training, which ranges from just a few hours of instruction to over 2,000 flight hours. Naval Air Training Command believes that students with prior flight experience perform better than those without prior flight experience in the first phase of training, Primary, but not in Advanced, the later phases of training. Our analysis focuses specifically on comparing performance in Advanced phases of training to ensure that Student Naval Aviators are being selected for aircraft within their piloting capabilities. Using data from March of 2020 to January of 2024, we analyze and quantify the performance of students with prior flight training in comparison to students without prior flight training throughout Primary and Advanced phases of the Naval Air Training. Our analysis employs various statistical tests and models including survival functions, linear models, regression trees, and random forests. We find that Student Naval Aviators with prior flight experience excel in Primary, but performance varies depending on which Advanced phase they were selected for.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
Communication Device Radiating Purely Dipole Structure
Get PDFThe invention relates to a communication device radiating a purely dipole structure. The communication device included a metallic sphere having a central axis and electrical wiring wound azimuthally around the central axis of the metallic sphere so that an electric current density of the electric wiring is proportional to a sine of a spherical elevation angle of the metallic sphere
CORROSION CONTROL ON THE LVC GRID — PERSISTENT AUGMENTED AND VIRTUAL ENVIRONMENTS IN SUPPORT OF AIRCRAFT MAINTENANCE
Get PDFIncludes Supplementary MaterialThe intricacy of aircraft systems of systems demands further innovation in aviation maintenance, repair, and overhaul (MRO). Like the jump from physical visual display boards on the walls of maintenance control to desktop networked management tools, the introduction of a persistent augmented and virtual environment (PAVE) to aid MRO operations presents the next major milestone. This work proposes MRO on Deck, an expansion of the “smart hangar” framework using a PAVE approach with digital twins and live, virtual, and constructive simulation components to support aviation logistics. As a proof of concept, we designed and developed an example tool that used the underlying PAVE and measured the usability of the tool in the context of visual inspections and aircraft corrosion control. The prototype demonstrated how a combination of several technological approaches, enriched with superior data visualization and intuitive user interaction, can support multiple stakeholders across aviation logistics. The proof of concept informed development operations for the F/A-18 Tracking Corrosion and Assessment Tool (FATCAT). FATCAT seeks to integrate augmented reality as a human interface for future artificial-intelligence enhanced maintenance job aids. The usability study showed the feasibility of adopting tools like FATCAT for operational maintenance in the not-too-distant future.Distribution Statement A. Approved for public release: Distribution is unlimited.Major, United States Marine CorpsNIWC-
THE 2003 OCCUPATION OF IRAQ: AN EXAMINATION OF THE INTELLIGENCE-DECISION-MAKER RELATIONSHIP
Get PDFIn March 2003, coalition forces invaded Iraq, overthrew the Ba’athist regime, and removed Saddam Hussein. Rather than quickly withdrawing its forces as planned, the United States became entangled for two decades as identity-based violence surged and Iraqi institutions dissolved. This thesis investigates how decision-makers failed to anticipate and plan for the disintegration of Iraqi society and institutions, questioning whether the root cause stemmed from intelligence failures. By examining pre-war intelligence reports and military plans, as well as post-conflict decision-making, this thesis finds that while intelligence gaps existed, the larger problem was the failure of intelligence to drive operations. This failure reflected shortcomings in the relationship between the intelligence personnel and decision-makers, which contributed to an environment where decision-makers made key plans and decisions despite intelligence gaps and contrary to intelligence reporting. The post-war conditions in Iraq demonstrate the disastrous consequences when decision-makers disregard intelligence and when intelligence personnel fail to persuade them to listen.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisLieutenant, United States Nav