Engineering Commons^™

Molecular Dynamics Model Of Carbon Nanotubes In Epon 862/Detda Polymer, Guttormur Arnar Ingvason

Doctoral Dissertations and Master's Theses

The aerospace industry is interested in increasing the strength while reducing the weight of carbon fiber composite materials. Adding single walled carbon nanotubes (SWCNT) to a polymer matrix can achieve that goal by improving delamination properties of the composite. Due to the complexity of polymer molecules and the curing process, few 3-D Molecular Dynamics simulations of a polymer-SWCNT composite have been run. Our model runs on the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS), with a COMPASS (Condensed phase Optimized Molecular Potential for Atomistic Simulations Studies) potential to represent the interactions between the atoms of the polymer and the SWCNT. This …

Development Of A Hybrid Vehicle Powertrain Test Laboratory, Bennet Samuel Soundarraj

Doctoral Dissertations and Master's Theses

During the last two years, Embry-Riddle Aeronautical University has installed and tested a fully functional eddy-current chassis dynamometer testing facility on campus. An automotive test facility requires a systems engineering approach to install, calibrate and commission a chassis dynamometer. This thesis shows that, the dynamometer test facility was successfully installed, commissioned and documented to safely support the power train development and testing. We can currently test the EcoCAR vehicle and a number of other front-wheel-drive vehicles at our university campus using the eddy current chassis dynamometer.

Investigation Into The Effects Of Wire Mesh On Tensile And Impact Properties Of Fiber Metal Laminates, Shivani A. Rudradat

Doctoral Dissertations and Master's Theses

An investigational study was conducted into the tensile and impact behavior of Fiber Metal Laminates by combining 5052 alumintrm mesh or2024-T3 aluminum sheets,2.47 N (8.9 oz) or 6.67 N (24 az) ShieldStand^® S fiberglass, and Hysol EA 9313 epoxy. Testing was performed under the guidelines of ASTM D3039-00 utilizing an lnstron 8802 Servohydraulic Materials Testing Instrument for tensile tests and ASTM D3763-06 utilizing an Inston 9250 HV Dynatup Impulse Impact Testing System for impact tests. Samples were strained at arate of 2 mrn/min for tensile tests and impacted with enetgies of 10 to 40 J in l0 J increments …

Robust Image-Based Visual Servo Control Of An Uncertain Missile Airframe, Murat Tunca Aygun

Doctoral Dissertations and Master's Theses

A nonlinear vision-based guidance law is presented for a missile-target scenario in the presence of model uncertainty and unknown target evasive maneuvers. To ease the readability of this thesis, detailed explanations of any relevant mathematical tools are provided, including stability definitions, the procedure of Lyapunov-based stability analysis, sliding mode control fundamentals, basics on visual servo control, and other basic nonlinear control tools. To develop the vision-based guidance law, projective geometric relationships are utilized to combine the image kinematics with the missile dynamics in an integrated visual dynamic system. The guidance law is designed using an image-based visual servo control method …

Flying The U-2, Art Saboski

ERAU Prescott Aviation History Program

Learn what it was like to fly the famous U-2, one of history’s most secretive aircraft, from a pilot who has done just that. Art Saboski spent most of his Air Force career flying the U-2; commanding U-2 organizations as well as planning and conducting reconnaissance/intelligence operations. He will give his unique perspectives on the high altitude aircraft, its history, development and current uses today.

The Effects Of Aircraft Certification Rules On General Aviation Accidents, Carolina Lenz Anderson

Doctoral Dissertations and Master's Theses

The purpose of this study was to analyze the frequency of general aviation airplane accidents and accident rates on the basis of aircraft certification to determine whether or not differences in aircraft certification rules had an influence on accidents. In addition, the narrative cause descriptions contained within the accident reports were analyzed to determine whether there were differences in the qualitative data for the different certification categories. The certification categories examined were: Federal Aviation

Regulations Part 23, Civil Air Regulations 3, Light Sport Aircraft, and Experimental-Amateur Built. The accident causes examined were those classified as: Loss of Control, Controlled Flight …

Comparison Of Three Angle Of Attack (Aoa) Indicators: A Usability Study, Camilo Jimenez

Doctoral Dissertations and Master's Theses

Angle of Attack (AOA) is an important aeronautical concept used to understand the performance status of an aircraft during different flight stages. The Federal Aviation Administration (FAA) has indicated the importance of developing and encouraging the use of affordable AOA based systems to increase inflight safety. Embry-Riddle Aeronautical University's flight department decided to install AOA indicators in its fleet of Cessna 172S, to increase safety and to help student pilots better understand this important concept. This paper presents a review of AOA, visual display design principles, and usability. This experimental study examined three different AOA indicators provided by the …

Performance Analysis Of Non-Linear Adaptive Control Laws Using Hardware In The Loop Of An Unmanned Aerial System, Brendon Lyons

Doctoral Dissertations and Master's Theses

In practical applications, an Unmanned Aerial System's (UAS) baseline performance is dictated by how well it can follow a given trajectory with limited stress on the actuators. However, these can be insufficient performance metrics when the UAS is allowed to adapt to an unpredicted external influence such as turbulence or actuation failure, while maintaining a satisfactory baseline performance.

In this thesis, different control laws based on the formation flight geometry problem, nonlinear dynamic inversion and an artificial immune system adaptive mechanism , are implemented in hardware-in-the-loop as a precursor for in-flight testing. These controllers are compared based on three performance …

Attitude Dynamics Of Debris Resulting From Upper Stage Fragmentation In Low Earth Orbit, Killian Marie

Doctoral Dissertations and Master's Theses

This thesis addresses the analysis of the attitude dynamics of pieces of space debris that could result from the fragmentation of a spent upper stage in low Earth orbit (LEO).

Up to now only whole objects of axisymmetric shape have been studied with the purpose of estimating their tumbling rates in LEO. Three shapes have been considered to be representative for the purpose of the study: a thin plate, a monocoque shell, an half conical shell and a spherical shell, and it has been assumed that they are fabricated from aluminum alloy. The motion of conducting body in a magnetic …

Observability And Confidence Of Stability And Control Derivatives Determined In Real Time, Alfonso Noriega

Doctoral Dissertations and Master's Theses

Stability and control derivatives of an aircraft were estimated from real flight test data in real time. A higher language block diagram library was developed for this purpose. Parameter identification techniques and requirements were used to detect and rate maneuvers present in the data. These ratings were used to blend newly calculated derivatives with previously known values by means of a Kalman filter. The Kalman filter output was used to identify the health of control surfaces actuators. Statistical and measured data were used to predict the probability that an actuator failure has occurred at any given time during the flight. …

Preliminary Design Of Blade And Disc Fixing For Aerospace Application Using Multi-Disciplinary Approach, Abdulhalim Twahir

Doctoral Dissertations and Master's Theses

The preliminary design phase of a turbine rotor has an important impact on the architecture of a new engine definition, as it sets the technical envelope of the product to be designed. Additionally, preliminary design cycle times are increasingly critical in capturing business opportunities in an ever competitive environment. Improving the accuracy of the preliminary design (pre-detailed design) is also necessary as not only does it significantly reduce the overall development of an engine, but also because any mistakes made at this stage can be extremely hard to rectify.

Previously, typical pre-detail fixing design cycle time was greater due to …

An Ergonomic Evaluation Of Aircraft Pilot Seats, Yolanda Nicole Andrade

Doctoral Dissertations and Master's Theses

Seat comfort has become increasingly important in today's society as we spend more time at consoles, instrument panels, or just online. However, seat comfort is hard to define and difficult to measure. Several measures both objective and subjective were used to evaluate seat comfort in commercially available average pilot seats. Three pilot seats, which had the same material and similar adjustments but different physical attributes, and a universal classroom seat, with different material and no adjustments, were compared by 20 volunteers using subjective and objective measures in a Latin square controlled repeated measures design. A Friedman's test was used to …

Mapping Automotive Like Controls To A General Aviation Aircraft, Christopher G. Carvalho

Doctoral Dissertations and Master's Theses

The purpose of this thesis was to develop fly-by-wire control laws enabling a general aviation aircraft to be flown with automotive controls, i.e. a steering wheel and gas/brake pedals. There was a six speed shifter used to change the flight mode of the aircraft. This essentially allows the pilot to have control over different aspects of the flight profile such as climb/descend or cruise. A highway in the sky was used to aid in the navigation since it is not intuitive to people without flight experience how to navigate from the sky or when to climb and descend.

Many believe …

Investigation Of Grid Adaptation To Reduce Computational Efforts For A 2-D Hydrogen-Fueled Dual-Mode Scramjet, Kam Keong Foo

Doctoral Dissertations and Master's Theses

A two-dimensional dual-mode scramjet flowpath is developed and evaluated using the ANSYS Fluent density-based flow solver with various computational grids. Results are obtained for fuel-off, fuel-on non-reacting, and fuel-on reacting cases at different equivalence ratios. A one-step global chemical kinetics hydrogen-air model is used in conjunction with the eddy-dissipation model. Coarse, medium and fine computational grids are used to evaluate grid sensitivity and to investigate a lack of grid independence. Different grid adaptation strategies are performed on the coarse grid in an attempt to emulate the solutions obtained from the finer grids. The goal of this study is to investigate …

Identification Of Causal Paths And Prediction Of Runway Incursion Risk Using Bayesian Belief Networks, Benjamin Jeffry Goodheart

Doctoral Dissertations and Master's Theses

In the U.S. and worldwide, runway incursions are widely acknowledged as a critical concern for aviation safety. However, despite widespread attempts to reduce the frequency of runway incursions, the rate at which these events occur in the U.S. has steadily risen over the past several years. Attempts to analyze runway incursion causation have been made, but these methods are often limited to investigations of discrete events and do not address the dynamic interactions that lead to breaches of runway safety. While the generally static nature of runway incursion research is understandable given that data are often sparsely available, the unmitigated …

Money Laundering Detection Framework To Link The Disparate And Evolving Schemes, Murad Mehmet, Duminda Wijesekera, Miguel F. Buchholtz

Journal of Digital Forensics, Security and Law

Money launderers hide traces of their transactions with the involvement of entities that participate in sophisticated schemes. Money laundering detection requires unraveling concealed connections among multiple but seemingly unrelated human money laundering networks, ties among actors of those schemes, and amounts of funds transferred among those entities. The link among small networks, either financial or social, is the primary factor that facilitates money laundering. Hence, the analysis of relations among money laundering networks is required to present the full structure of complex schemes. We propose a framework that uses sequence matching, case-based analysis, social network analysis, and complex event processing …

Collaborative Audio Transcription And Repair As A Method For Novice Pilots To Learn Approach Briefing Crew Resource Management (Crm) Skills, William A. Tuccio Ph.D.

Doctoral Dissertations and Master's Theses

The growth of aviation in scope, scale, and complexity increases the demands for student learning, including crew resource management (CRM) skills. Instructor facilitated methods have proven effective for CRM skill learning. This study investigated a method of collaborative audio transcription and repair based learning (CTRBL) offering the potential for reduced demand upon instructor resources for CRM learning. The theorybased CTRBL method was used in this study as a way for novice pilots to learn the CRM skill of conducting a crew approach briefing with a focus on risk mitigation. Learning methods used to develop the CTRBL method were drawn from …

The Effects Of Ethical Leadership And Organizational Safety Culture On Safety Outcomes, David Ronald Freiwald

Doctoral Dissertations and Master's Theses

This dissertation investigated the relationship among ethical leadership, an ethical workplace climate, safety culture, safety behaviors, and measured safety outcomes of workers in the high reliability organizations of aviation and healthcare. The primary objective was to develop a model linking these factors and assess their fit within the model. A secondary objective was to examine differences between the two populations. In this study, a 101-item instrument was used to collect and analyze employee responses on ten factors comprising the model. Structural equation modeling – path analysis was used for testing and evaluating relations using a combination of statistical analysis and …

Fighters Pilot Helmet Design For 5th Generation Aircraft, Ian R. Mcandrew, Katherine A. Moran, Andrew Little

Publications

Fighter pilots’ helmets have become more complex and heavier resulting in long term implications to pilots musculoskeletal systems as they fly and experience high g-load. Current research has identified design changes to the helmet to accommodate the ancillary items fitted to assist pilots but at the expense of comfort and additional loading. Its manufacturing requirements and adaptations to offer bespoke solutions are addressed to allow for training and operational usage. To produce the next generation of helmets that reduce long-term injuries, from g-loads and asymmetrical ancillaries requires individual considerations, unique manufacturing requirements and the ability to support with service spares …

Multi-Stage Axial Compressor With Counter-Rotation, Vinod Gehlot, Magdy S. Attia, Divyam Garg

Publications

A multi-stage axial compressor incorporating a counter-rota­tional movement is provided with a series of rotors mounted along and driven by a driveshaft, and a geared counter-rotat­ing outer casing. A planetary gear system is assembled along a static casing, which can be assembled as a forward or aft casing for the compressor. The bearings of the planetary gear system typically will be aligned concentrically with a center rotor drum assembly mounted along the single driveshaft. The counter-rotating drum assembly will be assembled over the rotor drum assembly and will be engaged by the forward and aft casings so as to provide …

Biofuel From Microalgae – A Review On The Current Status And Future Trends, Rajee Olaganathan, May Zaw Htet, Lim Yan Ling, Sek Hui Yun

Publications

The constant reliance on fossil fuel energy resources is unsustainable, due to both depleting world reserves and increasing green house gas emissions associated with their use and thus there are dynamic research at the global level envisioned at developing alternative renewable and potentially carbon neutral solid, liquid and gaseous biofuels as alternative energy resources. The contemporary knowledge and technology predictions have proved that among the third generation biofuels especially those derived from microalgae are considered the best reasonable alternative energy resource compared to undeniable drawbacks of first and second generation biofuels. Moreover, its efficiency to sequester carbon from the atmosphere …

Geometric And Pattern Recognition Combined Algorithms Applied To Digital Image Processing In Aerial Search And Rescue Applications, Jamil Efren Anaguano Correa

Doctoral Dissertations and Master's Theses

The difficult task of generating an automated target detection system from aerial imagery can be achieved through different approaches. However, the robustness of any machine vision system lays on the implementation of vision algorithms. By combining geometric and pattern recognition algorithms, a more effective machine vision scheme is developed. Three modules-Color Identification (CIM), Color Matching (CMM), and Pattern Recognition (PRM)- work as main filters to process images and predict the location of targets based on a set templates. Multiple target detection is also accomplished by implementing a hide and seek method where all matching objects are scanned individually and isolated …

Public Perception Of Unmanned Aerial Systems (Uas): A Survey Of Public Knowledge Regarding Roles, Capabilities, And Safety While Operating Within The National Airspace System (Nas), Dennis Vincenzi, David Ison, Dahai Liu

Publications

A variety of challenges to the successful assimilation of Unmanned Aircraft Systems (UASs) into the National Airspace System (NAS) exists. Aside from technical and legislative challenges, another setback has recently surfaced when the FAA suspended its selection process for UAS test sites due to privacy concerns. This new obstacle has the potential to further delay UAS integration. Very little literature or coverage of UAS domestic operations and accidents have been published and made available to the public at large. As a result, the public has very little information upon which to form any realistic or reasonable opinions concerning the integration …

Fluid-Structure Interaction And Multidisciplinary Design Analysis Optimization Of Composite Wind Turbine Blade, Naishadh G. Vasjaliya

Doctoral Dissertations and Master's Theses

A multidisciplinary design analysis optimization (MDAO) process is defined for a composite wind turbine blade to optimize its aerodynamic and structural performance by developing a fluid-structural interaction (FSI) system. The objectives are to maximize aerodynamic efficiency and structural robustness while reducing blade mass and total cost. In the previous research, a MDO process of a composite wind turbine blade has been pioneered as an effective process to develop structurally optimized blade design. Present MDAO process is defined in conjunction with structural and aerodynamic performance of the blade which is divided into three steps and the design variables considered are related …

Analysis Of Fatal General Aviation Accidents Occurring From Loss Of Control On Approach And Landing, Brittnee Nicholle Branham

Doctoral Dissertations and Master's Theses

According to the National Transportation Safety Board (NTSB), loss of control in-flight is the greatest cause of general aviation accidents. The purpose of this study was to determine the most frequently occurring probable causes and contributing factors from loss of control in-flight. This study used the Pareto principle and methodology developed by the General Aviation Joint Steering Committee to analyze accidents retrieved from the NTSB's Aviation Accident Database. The results showed that 73% of the accidents contained the contributing factor of "PILOT - Failure to maintain airspeed" across the three categories of reciprocating engine aircraft, turbine engine aircraft, and experimental-amateur …

Privacy And Unmanned Aerial Systems Integration In The National Aerospace System: Navigating Fourth Amendment Concerns, Dennis Vincenzi, David Ison, Dahai Liu

Publications

A variety of challenges to the successful assimilation of UASs into the National Airspace System (NAS) currently exist. Technical issues and human factors related hurdles have brought forth a range of research efforts to help to mitigate or resolve these challenges. Regulations and legislation play a significant role in controlling or restricting the use of UASs in the NAS. Currently there appears to be a contraposition of sentiment between the Federal Aviation Administration and Congress on the inclusion of UASs in the NAS. Congress has called for the adoption of UAS operations in the NAS by 2015 yet the FAA …

Computing Radiation Exchange, Jonathan L. Nutzati Fontaine

Doctoral Dissertations and Master's Theses

A computational tool to simulate thermal radiation between surfaces is developed. The output is verified against cases for which the analytical solutions are available. The tool can be used as a stand-alone program, or as an interactive module for CFD. In such an application the module would augment other heat transfer boundary conditions. The tool is demonstrated by post-processing surface temperature field data from a supersonic CFD calculation. The result is a net thermal radiation surface data field - the black body radiative effluxes as functions of temperature, less the integrated influxes multiplied by their geometric view factors from other …

Aviation Weather And Decision Making: A Human Factors Perspective, Beth Blickensderfer, Jessica Cruit, Michael Vincent

Aviation Weather Training Research

• A History of Decision Making Research
• Pilot Decision Making
• Future Research Directions

The Effects Of Angle-Of-Attack Indication On Aircraft Control In The Event Of An Airspeed Indicator Malfunction, Claas Tido Boesser

Doctoral Dissertations and Master's Theses

Analysis of accident data by the Federal Aviation Administration, the National Transportation Safety Board, and other sources show that loss of control is the leading cause of aircraft accidents. Further evaluation of the data indicates that the majority of loss of control accidents are caused by the aircraft stalling. In response to these data, the Federal Aviation Administration and the General Aviation Joint Steering Committee emphasize the importance of stall and angle-of-attack awareness during flight. The high-profile crash of Air France Flight 447, in which pilots failed to recover from a self-induced stall, reinforced concerns over the need for improved …

A Descriptive Analysis Of Public Comments Submitted In Response To Notice Of Proposed Rules On Air Carrier Pilot Qualification, Amy Chaffee Doolittle

Doctoral Dissertations and Master's Theses

In 2009, the crash of Colgan Flight 3407 in Buffalo, NY raised concerns regarding the adequacy of current pilot qualification standards for entering air carrier operations. In response, the U.S. Congress enacted Public Law 111-216, which requires a pilot to hold an Airline Transport Pilot (ATP) certificate in order to be qualified as a flight crewmember under 14 CFR, part 121, and also allows the Federal Aviation Administration (FAA) to modify the requirements to obtain an ATP certificate. In February 2012, the FAA issued a Notice of Proposed Rulemaking (NPRM) outlining these requirements and calling for public comments on the …