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- Doctoral Dissertations and Master's Theses (16)
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Articles 1 - 30 of 71
Full-Text Articles in Engineering
Low Cost Magnetometer Calibration And Distributed Simultaneous Multipoint Ionospheric Measurements From A Sounding Rocket Platform, Joshua W. Milford
Low Cost Magnetometer Calibration And Distributed Simultaneous Multipoint Ionospheric Measurements From A Sounding Rocket Platform, Joshua W. Milford
Doctoral Dissertations and Master's Theses
Low-cost and low-size-weight-and-power (SWaP) magnetometers can provide greater accessibility for distributed simultaneous measurements in the ionosphere, either onboard sounding rockets or on CubeSats. The Space and Atmospheric Instrumentation Laboratory (SAIL) at Embry-Riddle Aeronautical University has launched a multitude of sounding rockets in recent history: one night-time mid-latitude rocket from Wallops Flight Facility in August 2022 and three mid-latitude rockets from White Sands Missile Range during the October 2023 annular solar eclipse. All rockets had a comprehensive suite of instruments for electrodynamics and neutral dynamics measurements. Among this suite was one science-grade three-axis fluxgate magnetometer (Billingsley TFM65VQS / TFM100G2) and up …
Application Of Density Altitude Climatology To General Aviation Impacts, Thomas A. Guinn Ph.D., Daniel J. Halperin Ph.D., Sarah Strazzo Ph.D.
Application Of Density Altitude Climatology To General Aviation Impacts, Thomas A. Guinn Ph.D., Daniel J. Halperin Ph.D., Sarah Strazzo Ph.D.
Journal of Aviation/Aerospace Education & Research
Density altitude (DA) plays a key role in flight safety because it helps pilots anticipate poor aircraft performance when temperatures are warmer than standard. In this study, a 30-year climatology of DA for the conterminous United States was created using the fifth-generation European Centre for Medium-Range Weather Forecasts atmospheric reanalysis of the global climate (ERA5) dataset was applied to four separate DA-based, aircraft-performance, rules-of-thumb for general aviation (GA) flight. The goal was to demonstrate a technique to create educational visualization tools showing the variation of operational flight impacts with both month and location. Four such parameters were chosen to show …
Impact Of Weather Factors On Airport Arrival Rates: Application Of Machine Learning In Air Transportation, Robert W. Maxson, Dothang Truong, Woojin Choi
Impact Of Weather Factors On Airport Arrival Rates: Application Of Machine Learning In Air Transportation, Robert W. Maxson, Dothang Truong, Woojin Choi
Publications
Weather is responsible for approximately 70% of air transportation delays in the National Airspace System, and delays resulting from convective weather alone cost airlines and passengers millions of dollars each year due to delays that could be avoided. This research sought to establish relationships between environmental variables and airport efficiency estimates by data mining archived weather and airport performance data at ten geographically and climatologically different airports. Several meaningful relationships were discovered from six out of ten airports using various machine learning methods within an overarching data mining protocol, and the developed models were tested using historical data.
Hyper-Local Weather Predictions With The Enhanced General Urban Area Microclimate Predictions Tool, Kevin A. Adkins, William Becker, Sricharan Ayyalasomayajula, Steven Lavenstein, Kleoniki Vlachou, David Miller, Marc Compere, Avinash Muthu Krishnan, Nickolas Macchiarella
Hyper-Local Weather Predictions With The Enhanced General Urban Area Microclimate Predictions Tool, Kevin A. Adkins, William Becker, Sricharan Ayyalasomayajula, Steven Lavenstein, Kleoniki Vlachou, David Miller, Marc Compere, Avinash Muthu Krishnan, Nickolas Macchiarella
Publications
This paper presents enhancements to, and the demonstration of, the General Urban area Microclimate Predictions tool (GUMP), which is designed to provide hyper-local weather predictions by combining machine-learning (ML) models and computational fluid dynamic (CFD) simulations. For the further development and demonstration of GUMP, the Embry–Riddle Aeronautical University (ERAU) campus was used as a test environment. Local weather sensors provided data to train ML models, and CFD models of urban- and suburban-like areas of ERAU’s campus were created and iterated through with a wide assortment of inlet wind speed and direction combinations. ML weather sensor predictions were combined with best-fit …
Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo
Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo
Student Works
Aircraft taxiing operations in the aerodrome were identified to consume the most jet fuel apart from the cruise phase of the flight. This was also well supported by various research associating taxi operations at large, congested airports, with high jet fuel consumption, high carbon emissions, and noise pollution. Existing literature recognised the potential to address the environmental issues of aerodrome taxi operations by operating External or Onboard Aircraft Ground Propulsion Systems (AGPS). Designed to power aircraft with sources other than their main engines, external Aircraft Ground Power Systems (AGPS) have shown the potential to significantly cut jet fuel consumption and …
Validated Question Bank For Assessing Pilot Knowledge Of Aviation Weather Appendix: Weather Product Interpretation Questions, Robert Thomas, Cassandra Dommingo, John Kleber, Jackie Mcsorely, Amber Cole, Thomas Guinn, Elizabeth Blickensderfer
Validated Question Bank For Assessing Pilot Knowledge Of Aviation Weather Appendix: Weather Product Interpretation Questions, Robert Thomas, Cassandra Dommingo, John Kleber, Jackie Mcsorely, Amber Cole, Thomas Guinn, Elizabeth Blickensderfer
General Aviation Weather Display Interpretation
This appendix supplements the Thomas et al. (2022) paper titled “Validated Question Bank for Assessing Pilot Knowledge of Aviation Weather ” which validates a set of weather product interpretation questions that can be used to measure a pilot’s understanding of weather. The assessment consists of 15 weather product interpretation topics which can be administered as a single 65-question survey or, as in the Thomas et al. (2022) study, two assessments of 33 and 32 questions each separated by topic. The set of 65 questions can be found in this appendix along with a table which demonstrates how to separate the …
Adaptive-Optimal Control Of Spacecraft Near Asteroids, Madhur Tiwari
Adaptive-Optimal Control Of Spacecraft Near Asteroids, Madhur Tiwari
Doctoral Dissertations and Master's Theses
Spacecraft dynamics and control in the vicinity of an asteroid is a challenging and exciting problem. Currently, trajectory tracking near asteroid requires extensive knowledge about the asteroid and constant human intervention to successfully plan and execute proximity operation. This work aims to reduce human dependency of these missions from a guidance and controls perspective. In this work, adaptive control and model predictive control are implemented to generating and tracking obstacle avoidance trajectories in asteroid’s vicinity.
Specifically, direct adaptive control derived from simple adaptive control is designed with e modification to track user-generated trajectories in the presence of unknown system and …
Applying Human Factors Heuristic Evaluation Tools To Improve Aviation Weather Displays: A Mismatch, John Kleber, Paige Lawton, Beth Blickensderfer
Applying Human Factors Heuristic Evaluation Tools To Improve Aviation Weather Displays: A Mismatch, John Kleber, Paige Lawton, Beth Blickensderfer
General Aviation Weather Display Interpretation
The evaluation of current Heuristic Evaluation Tools for use in assessing Aviation Weather Displays.
Aviation Human-In-The-Loop Simulation: Best Practices For Subjective Performance Measurement, John Kleber, Beth Blickensderfer
Aviation Human-In-The-Loop Simulation: Best Practices For Subjective Performance Measurement, John Kleber, Beth Blickensderfer
Aviation Weather Training Research
Subjective performance measurements are a useful tool for researchers and instructors to evaluate tasks that are difficult to quantify with objective data pulled from a simulator or the physiological data of pilots. Subjective performance measurements are non-intrusive measures typically conducted by human raters. Some recommendations for utilizing subjective measures include reducing the workload of the human raters, concealing the aim of the experiment from participants, utilizing multiple raters to evaluate each participant, providing raters with proper training, developing error-resistant rater forms and, including both subjective and objective measures when possible.
An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii
An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii
Doctoral Dissertations and Master's Theses
The purpose of this dissertation was to bridge the existing literature gap of outdated contextual factor (CF) research through examination and determination of current General Aviation (GA) Title 14 Code of Federal Regulations (CFR) Part 91 visual flight rules (VFR)-into-instrument meteorological condition (IMC) contextual factors. Contextual factors are a multifaceted arrangement of pertinent events or occurrences contributing to pilot accidents in weather-related decision-making errors. A total of 46 contextual factors were identified and examined from the reviewed research literature. The study examined and determined the presence of the 46 contextual factors, frequencies, and manifestations in the GA VFR-into-IMC Aviation Accident …
Optimization Of Spacecraft Formations About Lagrange Points For The Next Generation Space Weather Prediction Mission, Roberto Cuéllar Rangel
Optimization Of Spacecraft Formations About Lagrange Points For The Next Generation Space Weather Prediction Mission, Roberto Cuéllar Rangel
Doctoral Dissertations and Master's Theses
This thesis’s work serves as proof of concept for the Next Generation Space Weather Prediction Mission, a multi-spacecraft mission at various libration points whose objective is to forecast Space Weather hazards with a 12day warning time. This thesis deals with the design and control of orbits of spacecraft formations at different libration points. The systems studied are SunEarth, SunVenus, SunMercury, and SunMars. The orbit design and formation keeping control of the spacecraft are solved simultaneously using an optimization software called DIDO. Initial conditions are obtained through two different strategies. The first one, by placing the spacecraft in a tetrahedral formation …
An Aviation Weather Preflight Decision Support Tool To Improve Ga Pilots Preflight And Inflight Performance, Jayde M. King
An Aviation Weather Preflight Decision Support Tool To Improve Ga Pilots Preflight And Inflight Performance, Jayde M. King
Doctoral Dissertations and Master's Theses
Low hour, inexperienced General Aviation (GA) pilots account for the majority of weather-related incidents, which often result in fatalities. Previous research identifies poor preflight planning practices and a lack of aviation weather knowledge as key contributing factors to the high novice private pilot accident and fatality rate. Research invested into resolving these issues often attempt to introduce new inflight weather technology to assist pilots with weather avoidance. However, these interventions usually result in pilots using the information to strategically navigate closer to degraded weather conditions (Beringer & Ball, 2004; Burgess & Thomas, 2004). Therefore, the purpose of this study was …
Assessing If Motivation Impacts General Aviation Pilots’ Persistence In Varying Weather Conditions, Sabrina Woods
Assessing If Motivation Impacts General Aviation Pilots’ Persistence In Varying Weather Conditions, Sabrina Woods
Doctoral Dissertations and Master's Theses
Continued flight under visual flight rules into instrument meteorological conditions is the predominant cause for fatal accidents by percentage, for general aviation aircraft operations. It is possible that a pilot’s motivation or reason for flying will override other safer, more logical courses of action when a hazard presents itself. The decision appears to stem from a willingness to persist in a course of action despite factors that indicate an alternate and safer course is warranted. This research addresses what is currently presumed about the decision to continue flying under visual flight rules into instrument conditions and marries those ideas with …
Development Of A Sensor Suite For Atmospheric Boundary Layer Measurement With A Small Multirotor Unmanned Aerial System, Kevin A. Adkins, Christopher J. Swinford, Peter D. Wambolt, Gordon Bease
Development Of A Sensor Suite For Atmospheric Boundary Layer Measurement With A Small Multirotor Unmanned Aerial System, Kevin A. Adkins, Christopher J. Swinford, Peter D. Wambolt, Gordon Bease
International Journal of Aviation, Aeronautics, and Aerospace
Small unmanned aerial systems (sUAS) are increasingly being used to conduct atmospheric research. Because of the dynamic nature and inhomogeneity of the atmospheric boundary layer (ABL), the ability of instrumented sUAS to make on-demand 3-dimensional high-resolution spatial measurements of atmospheric parameters makes them particularly suited to ABL investigations. Both fixed-wing and multirotor sUAS have been used for ABL investigations. Most investigations to date have included in-situ measurement of thermodynamic quantities such as temperature, pressure and humidity. When wind has been measured, a variety of strategies have been used. Two of the most popular techniques have been deducing wind from inertial …
A Proposed Taxonomy For General Aviation Pilot Weather Education And Training, John M. Lanicci, Thomas A. Guinn, Jayde M. King, Beth Blickensderfer, Robert Thomas, Yolanda Ortiz
A Proposed Taxonomy For General Aviation Pilot Weather Education And Training, John M. Lanicci, Thomas A. Guinn, Jayde M. King, Beth Blickensderfer, Robert Thomas, Yolanda Ortiz
Journal of Aviation/Aerospace Education & Research
As General Aviation (GA) safety continues to remain a focus of the aviation community, GA pilot weather education and training continues to be an active area of interest within the research community. This study introduces a taxonomy for organizing GA pilot weather education and training materials that was originally conceived as part of the FAA’s Weather Technology In the Cockpit research program. The taxonomy is built upon three main knowledge categories, or tiers:1) Weather Phenomena (which includes hazards); 2) Weather Hazard Products; and 3) Weather Hazard Product Sources and their Application. The concept behind the categorization is to link knowledge …
How Airport Construction Will Evolve With The Increased Effects Of Climate Change, Xavier M. Ashley
How Airport Construction Will Evolve With The Increased Effects Of Climate Change, Xavier M. Ashley
Beyond: Undergraduate Research Journal
This report addressed the effects rising global temperatures resulting from climate change have had on flight operations in their entirety. The research objective was to discover what methods could enhance climate adaptation in airport construction, as higher mean-surface temperatures have an increasingly negative effect on aircraft performance. The findings would primarily be of interest to the Federal Aviation Administration (FAA) Primary Office presiding over the planning and development of airports. Overall, the report provided a comprehensive analysis of global warming’s effects on aviation, including the implications of degraded aircraft performance and sea-level rise for coastal airports. Additionally, it examined comparative …
Aviation Weather Products In General Aviation : Interpretability And Usability Research Trends, Jacqueline Mcsorley, Jayde King, Beth Blickensderfer
Aviation Weather Products In General Aviation : Interpretability And Usability Research Trends, Jacqueline Mcsorley, Jayde King, Beth Blickensderfer
General Aviation Weather Display Interpretation
- Introduction
- Current Study
- Trends
- Summary
- Conclusion
Exploring Perceived Usability And Interpretability Of Aviation Weather Products Among Ga Pilots, Jackie Mcsorley, Jayde King, Beth Blickensderfer
Exploring Perceived Usability And Interpretability Of Aviation Weather Products Among Ga Pilots, Jackie Mcsorley, Jayde King, Beth Blickensderfer
General Aviation Weather Display Interpretation
- Introduction
- Results
- Discussion
- Current Investigations
Efficacy Of The Localized Aviation Mos Program In Ceiling Flight Category Forecasts, Douglas D. Boyd, Thomas A. Guinn, Thomas A. Guinn
Efficacy Of The Localized Aviation Mos Program In Ceiling Flight Category Forecasts, Douglas D. Boyd, Thomas A. Guinn, Thomas A. Guinn
Publications
(1) Background: Flying in instrument meteorological conditions (IMC) carries an elevated risk of fatal outcome for general aviation (GA) pilots. For the typical GA flight, aerodrome-specific forecasts (Terminal Aerodrome Forecast (TAF), Localized Aviation Model Output Statistics Program (LAMP)) assist the airman in pre-determining whether a flight can be safely undertaken. While LAMP forecasts are more prevalent at GA-frequented aerodromes, the Federal Aviation Administration (FAA) recommends that this tool be used as supplementary to the TAF only. Herein, the predictive accuracy of LAMP for ceiling flight categories of visual flight rules (VFR) and instrument flight rules (IFR) was determined. (2) Methods: …
Combined Report: Aviation Weather Knowledge Assessment & General Aviation (Ga) Pilots’ Interpretation Of Weather Products, Beth Blickensderfer, John Lanicci, Thomas A. Guinn, Robert Thomas, Jennifer E. Thropp, Jayde King, Yolanda Ortiz, Jessica Cruit, Nicholas Defilippis, Krijn Berendschot, Jacqueline Mcsorley, John Kleber
Combined Report: Aviation Weather Knowledge Assessment & General Aviation (Ga) Pilots’ Interpretation Of Weather Products, Beth Blickensderfer, John Lanicci, Thomas A. Guinn, Robert Thomas, Jennifer E. Thropp, Jayde King, Yolanda Ortiz, Jessica Cruit, Nicholas Defilippis, Krijn Berendschot, Jacqueline Mcsorley, John Kleber
General Aviation Weather Display Interpretation
Prior research has indicated that general aviation (GA) pilots may lack adequate knowledge of aviation weather concepts and skill at interpreting aviation weather displays. Therefore, the purpose of the current project was to develop and validate a comprehensive set of aviation weather knowledge and interpretation multiple-choice questions, and in turn, to use the questions to assess pilot understanding of aviation weather concepts and displays. An interdisciplinary research team that included two meteorologists, one Gold Seal Certificated Flight Instructor (CFI), a human factors psychologist, and several human factors graduate students performed this research.
Preflight Weather Worksheet, Embry-Riddle Aeronautical University
Preflight Weather Worksheet, Embry-Riddle Aeronautical University
Weather Training Modules
Preflight Weather Worksheet
- Big Picture
- Hazards
- Visibility
Usability Analysis Of Convective Sigmets, Jackie Mcsorley, Beth Blickensderfer
Usability Analysis Of Convective Sigmets, Jackie Mcsorley, Beth Blickensderfer
General Aviation Weather Display Interpretation
- Introduction
- Methods
- Results
○ Interface Analysis: System Usability Scale
○ Workload Analysis: NASA-TLX
- Discussion
- Current Investigations
Aviation Weather Products In General Aviation: Interpretability And Usability Research Trends, Jacqueline Mcsorley, Jayde King, Beth Blickensderfer
Aviation Weather Products In General Aviation: Interpretability And Usability Research Trends, Jacqueline Mcsorley, Jayde King, Beth Blickensderfer
General Aviation Weather Display Interpretation
As a result of advances in weather forecasting and technology, today’s General Aviation (GA) pilots have access to a wealth of aviation weather information. During pre-flight planning, GA pilots may access weather radar images, satellite pictures, winds, and forecast maps. During flight, pilots can access in-cockpit weather displays, as well as, handheld portable weather devices. Despite the increasing advancement and accessibility of weather displays, there is limited research addressing the interpretability of both in-cockpit and preflight weather displays. This is particularly concerning considering that preflight planning and poor product interpretability have been cited as possible contributing factors for GA weather …
Uas Flight Operations In Complex Terrain: Assessing The Agricultural Impact From Hurricane Maria In The Central Mountainous Region Of Puerto Rico, Kevin Adkins
Publications
Hurricane Maria struck Puerto Rico in September 2017 as a Category 4 storm causing major damage to infrastructure, agriculture and natural ecosystems, as well as the loss of many lives. Among the crops hardest hit was coffee, one of the most important crops in Puerto Rico. As a perennial system, coffee takes various production forms along a gradient from high shade/biodiversity coffee farms to low shade coffee monocultures and therefore offers an ideal means for the study of resistance and resilience of an agroecosystem to weather and climate disturbance. During the summer of 2018, 14 impacted farms across the production …
Urban Flow And Small Unmanned Aerial System Operations In The Built Environment, Kevin A. Adkins
Urban Flow And Small Unmanned Aerial System Operations In The Built Environment, Kevin A. Adkins
International Journal of Aviation, Aeronautics, and Aerospace
The Federal Aviation Administration (FAA) has put forth a set of regulations (Part 107) that govern small unmanned aerial system (sUAS) operations. These regulations restrict unmanned aircraft (UA) from flying over people and their operation to within visual line of sight (VLOS). However, as new applications for unmanned aerial systems (UAS) are discovered, their capabilities improve, and regulations evolve, there is an increasing desire to undertake urban operations, such as urban air mobility, package delivery, infrastructure inspection, and surveillance. This built environment poses new weather hazards that include enhanced wind shear and turbulence. The smaller physical dimensions, lower mass and …
On Atmospheric Lapse Rates, Nihad E. Daidzic
On Atmospheric Lapse Rates, Nihad E. Daidzic
International Journal of Aviation, Aeronautics, and Aerospace
We have derived and summarized and most important atmospheric temperature lapse rates. ALRs essentially govern vertical atmospheric air stability and creation of some cloud types. The sensitivity analysis of various atmospheric lapse rates and their dependence on actual ideal-gas air properties and gravitational attraction was conducted for the first time to the best of our knowledge. SALR, which has DALR as the upper asymptote, showed steepest decrease at around 9 degrees Celsius then flattening out and apparently approaching another asymptotic solution which has not been investigated as it falls outside of the terrestrial temperature range. ISA lapse rates are adopted …
A New Model For Lifting Condensation Levels Estimation, Nihad E. Daidzic Ph.D., Sc.D.
A New Model For Lifting Condensation Levels Estimation, Nihad E. Daidzic Ph.D., Sc.D.
International Journal of Aviation, Aeronautics, and Aerospace
Knowledge of and the ability to predict lifting condensation levels (LCL) is important ingredient in weather predictions, cloud formation, planetary albedo and Earth’s energy balance. It is also essential topic in aviation safety and flight operations. In this article, we derive a new model of LCL and compare it to some older commonly-used models. This includes also the recently published Romps’ (2017) model. The new model presented here includes dependence, however weak, of the surface atmospheric pressure and the specific humidity on the LCL height and temperature. Such is not the case with widely used models and expressions by Espy …
Challenges For Flight Instructors Teaching Weather Information, Robert Thomas, Thomas A. Guinn
Challenges For Flight Instructors Teaching Weather Information, Robert Thomas, Thomas A. Guinn
Aviation Weather Training Research
- Flight Instructors face a challenge when teaching/learning weather information
- Multiple overlapping resources for aviation weather
- AC takes longer timeframe to update –problem for quick updates of information
Assessing Ga Pilots' Preflight Weather Planning Mental Models, Yolanda Ortiz, Beth Blickensderfer, Thomas A. Guinn
Assessing Ga Pilots' Preflight Weather Planning Mental Models, Yolanda Ortiz, Beth Blickensderfer, Thomas A. Guinn
General Aviation Weather Display Interpretation
Purpose, To assess GA Pilots' ability to:
- Obtain the Appropriate Weather Information
- Interpret the Data
- Apply the Information to a Given Flight Route
Interpreting Aviation Weather Products: Follow-Up Study With Aopa Members, Beth Blickensderfer, Thomas A. Guinn, Thomas Bob, Jayde King, Yolanda Ortiz, Nick Defilippis, Quirijn Berendschot, Jacqueline Mcsorley
Interpreting Aviation Weather Products: Follow-Up Study With Aopa Members, Beth Blickensderfer, Thomas A. Guinn, Thomas Bob, Jayde King, Yolanda Ortiz, Nick Defilippis, Quirijn Berendschot, Jacqueline Mcsorley
General Aviation Weather Display Interpretation
Purpose
- Use the questions we developed in Phase I
- Include pilots that are more representative of GA (age, flight hours/experience); Collaborate with AOPA
- Examine: Knowledge about aviation weather products; Differences between levels of flight certificate and/or ratings