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Full-Text Articles in Aerospace Engineering

Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano Jul 2026

Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano

Publications

The inner surface pressure of an axisymmetric inlet/isolator model was measured using anodized-aluminum pressure-sensitive paint (PSP) viewing through cast acrylic. Temperaturesensitive paint was utilized to correct for the PSP’s temperature sensitivity. The model was tested under Mach 5.7 flow at 𝑹𝒆 = 7.1 ×106 /m under conventional noise conditions. Transverse jet injection with jet-to-inlet mass-flow ratios up to 0.8 was used to induce unstart in the inlet/isolator. Background-oriented schlieren visualization of the inlet shocks was collected simultaneously with the PSP to determine when the inlet unstarted. Computational fluid dynamics results were used to determine off-wall flow structures and quantify approach …


Meeting The Moment With Ai-Employer Informed Education, Brent Terwilliger, John Faraca May 2026

Meeting The Moment With Ai-Employer Informed Education, Brent Terwilliger, John Faraca

Publications

As artificial intelligence transforms aviation, aerospace, and autonomy-related sectors, higher education must adapt to meet evolving workforce demands. This session shares emerging findings from a nationwide study led by Embry-Riddle Aeronautical University, focused on employer perceptions of AI adoption, responsible use, and workforce preparedness in domains including uncrewed systems, space systems, robotics, and advanced air mobility. Based on a structured survey and follow-up interviews, the presentation explores how organizations are using AI tools, from generative platforms to enterprise systems, and defining effective and inappropriate use in operational contexts. Participants will gain insight into critical concerns (e.g., data privacy, compliance, security, …


Simulation Results Of Spaceborne Ssa Using A Comprehensive Passive Radar Model, Chinmay Gaikwad, Filipe Senra, Thomas Alan Lovell, Hao Peng, Berker Pekoz, Tianyu Yang Jan 2026

Simulation Results Of Spaceborne Ssa Using A Comprehensive Passive Radar Model, Chinmay Gaikwad, Filipe Senra, Thomas Alan Lovell, Hao Peng, Berker Pekoz, Tianyu Yang

Publications

In this paper, a high-fidelity simulation framework is developed to assess the feasibility of tracking space debris using a large low-Earth orbit (LEO) satellite constellation equipped with onboard passive radar sensors. By exploiting illumination from a distributed network of ground-based transmitters, the constellation provides consistent line-of-sight access to debris objects at higher altitudes, enabling angles-only detection and tracking. This approach yields a scalable, automated, and cost-effective architecture for next-generation space surveillance and contributes to more resilient space traffic management. A complete angles-only passive-radar orbit-determination pipeline is introduced and demonstrated. Initial orbital states are generated using a rate-aware constrained admissible-region multiple-hypothesis …


Sustainable Practices For Aircraft Decommissioning And Recycling In A Circular Aviation Economy, Eva Maleviti, Dimitra Papadaki Nov 2025

Sustainable Practices For Aircraft Decommissioning And Recycling In A Circular Aviation Economy, Eva Maleviti, Dimitra Papadaki

Publications

The aviation industry requires a series of actions that will transform its current status, aiming for sustainable operations. Aviation’s end-of-life stream is a pivotal lever for circularity, yet current dismantling and recycling practices leave significant value unrealized. Circular Economy could be considered as a transformational approach to the aviation industry and address its environmental and economic challenges, meeting sustainability principles. This study conducts a PRISMA-guided qualitative systematic review across academic and industry sources to synthesize regulations, technologies, and economics of aircraft decommissioning. It aims to quantify material recovery potential and environmental gains at the aircraft level and assess technology readiness …


Insights On Ai-Supported Uncrewed And Autonomous Systems Education, Brent A. Terwilliger Ph. D, John Faraca Oct 2025

Insights On Ai-Supported Uncrewed And Autonomous Systems Education, Brent A. Terwilliger Ph. D, John Faraca

Publications

Artificial Intelligence (AI) related technology is reshaping the educational experience in programs focused on uncrewed and autonomous systems, aviation, robotics, and aerospace, with growing implications for workforce readiness and cross-sector innovation. Early survey data, capturing student, educator, and employer perspectives, reveals that AI-supported tools are notably changing student engagement, communication, and skills development. Initial indications underscores the importance of AI proficiency and technological familiarity in hiring and workforce development, particularly in technical and operational roles. Key areas of focus include the use of AI to strengthen outreach and interactivity; enrich instruction through intelligent simulations; inform curricular improvements using data analytics; …


Terra Lunaris: Assessment Of A Lunar Habitat For Scientific Astronauts, Space Miners, Or Space Tourists, Dirk Schumann, Robert A. Goehlich Sep 2025

Terra Lunaris: Assessment Of A Lunar Habitat For Scientific Astronauts, Space Miners, Or Space Tourists, Dirk Schumann, Robert A. Goehlich

Publications

This conceptual paper explores ground- based habitable space modules for various applications. The Terra Lunaris concept serves as the baseline and is evaluated in comparison to existing and theoretical studies in this field. Terra Lunaris is a compact hybrid habitat that expands to offer nearly four times its transport volume by combining rigid modules with an inflatable shell. With most interior elements pre-installed and foldable, setup time and complexity are minimized. The design integrates technical zones, living quarters, and shared spaces, while also supporting psychological well-being under extreme conditions. The paper provides both qualitative and quantitative analyses of lunar habitation …


Flight Crew And Aviation Sustainability, Eva Maleviti Feb 2025

Flight Crew And Aviation Sustainability, Eva Maleviti

Publications

Sustainable Development

The concept of sustainable development was defined in the World Commission on Environment and Development’s (WCED) 1987 Brundtland Report ‘’Our Common Future’’. The Brundtland Commission aimed to help world nations towards sustainable development. Then, sustainable development became an essential concept in the vocabulary of politicians, practitioners, and planners.


The Future Of Aviation: Becoming An Evtol Pilot – Faa’S New Regulations Open Up Career Opportunities, Sarah Nilsson Jan 2025

The Future Of Aviation: Becoming An Evtol Pilot – Faa’S New Regulations Open Up Career Opportunities, Sarah Nilsson

Publications

As the aviation industry stands on the brink of a revolutionary change, aspiring pilots are increasingly drawn to the exciting prospect of flying electric Vertical Takeoff and Landing (eVTOL) aircraft. The allure of this cutting-edge technology has many asking: “How does one become an eVTOL pilot in the United States?” This question opens up a cascade of inquiries about the future of flight training, the certification process and the transition for existing pilots into this new realm of aviation like:

• What will the flight training curriculum look like for eVTOL aircraft?

• Who will be the pioneering Certified Flight …


Hydrogen Standards And Aviation Sustainability, Eva Maleviti, Evan Stamoulis, Elen Paraschi Jan 2025

Hydrogen Standards And Aviation Sustainability, Eva Maleviti, Evan Stamoulis, Elen Paraschi

Publications

Standards from ISO, SAE, and ASTM are essential for certification, safety, and sustainability validation.


Hydrogen Readiness In Aviation & Challenges- Technology Meets Regulation And Market Demand, Eva Maleviti Jan 2025

Hydrogen Readiness In Aviation & Challenges- Technology Meets Regulation And Market Demand, Eva Maleviti

Publications

Where technology meets regulation and market demand.


An Operational Field Study: A Comparison Of Piloting Uncrewed Underwater Vehicles And Uncrewed Aircraft Systems, David Thirtyacre, Joseph Cerreta, Pete Miller, Kimberly Luthi, Jolee Thirtyacre Jan 2025

An Operational Field Study: A Comparison Of Piloting Uncrewed Underwater Vehicles And Uncrewed Aircraft Systems, David Thirtyacre, Joseph Cerreta, Pete Miller, Kimberly Luthi, Jolee Thirtyacre

Publications

and operations, the ability to cross-train personnel in both Uncrewed Underwater Vehicles and Small Uncrewed Aircraft System operations has become a focal point for efficiency and workforce optimization. This study presents a comparative analysis of the operational and human factor considerations involved in piloting mini UUV and sUASs, highlighting the key similarities and differences in control methods, environmental influences, navigation, emergency procedures, and situational awareness. A qualitative experimental field study was conducted between July 2024 and October 2024, involving real-world deployments of both systems in maritime and aerial environments. Findings indicated that while UUV and sUAS operators relied on remote …


Factors Contributing To Fatalities In Helicopter Emergency Medical Service Accidents, Jenna Korentsides, Joseph R. Keebler, Mihhail Berezovski, Alex Chaparro Jan 2025

Factors Contributing To Fatalities In Helicopter Emergency Medical Service Accidents, Jenna Korentsides, Joseph R. Keebler, Mihhail Berezovski, Alex Chaparro

Publications

INTRODUCTION: T his study aimed to update and reinforce previous research on helicopter emergency medical service accidents in the United States. By investigating predictors of fatalities after helicopter emergency medical service crashes through the application of machine learning techniques, we updated existing data sets and sought to uncover patterns that traditional analysis might not reveal.

METHODS: Using the National Transportation Safety Board database, the authors analyzed a dataset of 267 helicopter emergency medical service accidents between 1991–2022. We first calculated fatalities odds ratios for each condition. We then plotted geospatial locations of all reported accidents. Finally, we used XGBoost regression …


Investigation Of A Busemann Intake At Negative Angle Of Attack, Mark E. Noftz, Andrew N. Bustard, Nicholas J. Bisek, Thomas J. Juliano, Joseph S. Jewell Jan 2025

Investigation Of A Busemann Intake At Negative Angle Of Attack, Mark E. Noftz, Andrew N. Bustard, Nicholas J. Bisek, Thomas J. Juliano, Joseph S. Jewell

Publications

A high-speed, shape-transitioned, inward-turning intake was tested in Purdue’s Boeing/AFOSR Mach 6 Quiet Tunnel. The inlet model, called the Indiana Inlet (INlet), had a total contraction ratio of 4.68:1 and a design point of Mach 6 at 0° angle of attack. The model was outfitted with a suite of high-frequency pressure transducers, and the external flowfield was imaged with high-speed schlieren photography. The INlet was tested under low freestream disturbance levels for a variety of freestream unit Reynolds numbers and at-4° angle of attack. An unsteady shockwave near the leading edge of the inlet forebody, indicative of boundary layer separation, …


The Future Of Flying: An Exploration Of New Aircraft Design And Energy Required To Support Advanced Air Mobility – Part 3, Sarah Nilsson Nov 2024

The Future Of Flying: An Exploration Of New Aircraft Design And Energy Required To Support Advanced Air Mobility – Part 3, Sarah Nilsson

Publications

Lecture exploring new aircraft design and energy required to support advanced air mobility.


The Future Of Flying: An Exploration Of New Aircraft Design And Energy Required To Support Advanced Air Mobility – Part 2, Sarah Nilsson Nov 2024

The Future Of Flying: An Exploration Of New Aircraft Design And Energy Required To Support Advanced Air Mobility – Part 2, Sarah Nilsson

Publications

Lecture exploring new aircraft design and energy required to support advanced air mobility.


The Future Of Flying: An Exploration Of New Aircraft Design And Energy Required To Support Advanced Air Mobility – Part 1, Sarah Nilsson Nov 2024

The Future Of Flying: An Exploration Of New Aircraft Design And Energy Required To Support Advanced Air Mobility – Part 1, Sarah Nilsson

Publications

Lecture exploring new aircraft design and energy required to support advanced air mobility.


Vertiport Ventures: Assessing Operational Feasibility For Evtol Integration In São Paulo’S Helipad And Heliport Infrastructure, Peter E. O'Reilly, Ramy A. Rahimi, Jorge Luiz Rosa Marques, Marco Aurélio Feitosa De A. L. Babadopulos1 Jul 2024

Vertiport Ventures: Assessing Operational Feasibility For Evtol Integration In São Paulo’S Helipad And Heliport Infrastructure, Peter E. O'Reilly, Ramy A. Rahimi, Jorge Luiz Rosa Marques, Marco Aurélio Feitosa De A. L. Babadopulos1

Publications

The objective of this study is to assess the operational viability of introducing Electric Vertical Take-Of and Landing (eVTOL) vehicles in São Paulo and its metropolitan area, utilizing existing helipads and helicopter infrastructure. eVTOL aircraft, capable of vertical take-of and landing like helicopters, difer from traditional helicopters in their propulsion systems, with eVTOLs typically featuring multiple smaller electric motor-driven propulsion units instead of internal combustion engines and mechanical transmissions (Schuchardt et al. 2023). The study specifcally targets eVTOLs with the capacity to transport a minimum of four passengers and one pilot for distances of at least 50 km. Appendix provides …


Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto Mar 2024

Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto

Publications

Highly diverse agroecosystems are increasingly of interest as the realization of farms’ invaluable ecosystem services grows. Simultaneously there has been an increased use of uncrewed aerial systems (UAS) in remote sensing as drones offer a finer spatial resolution and faster revisit rate than traditional satellites. With the combined utility of UAS and the attention on agroecosystems, there exists an opportunity to assess UAS practicality in highly biodiverse settings. In this study, we utilized UAS to collect fine-resolution 10-band multispectral imagery of coffee agroecosystems in Puerto Rico. We created land cover maps through a pixel-based supervised classification of each farm and …


Immersive Framework For Designing Trajectories Using Augmented Reality, Joseph Anderson, Leo Materne, Karis Cooks, Michelle Aros, Jaia Huggins, Jesika Geliga-Torres, Kamden Kuykendall, David Canales, Barbara Chaparro Jan 2024

Immersive Framework For Designing Trajectories Using Augmented Reality, Joseph Anderson, Leo Materne, Karis Cooks, Michelle Aros, Jaia Huggins, Jesika Geliga-Torres, Kamden Kuykendall, David Canales, Barbara Chaparro

Publications

The intuitive interaction capabilities of augmented reality make it ideal for solving complex 3D problems that require complex spatial representations, which is key for astrodynamics and space mission planning. By implementing common and complex orbital mechanics algorithms in augmented reality, a hands-on method for designing orbit solutions and spacecraft missions is created. This effort explores the aforementioned implementation with the Microsoft Hololens 2 as well as its applications in industry and academia. Furthermore, a human-centered design process and study are utilized to ensure the tool is user-friendly while maintaining accuracy and applicability to higher-fidelity problems.


On Progress In Exploring Controlled Viscous Limit-Cycle Oscillations In Modified Glauert Airfoil, Ethan Deweese, Lap Nguyen, Erik Vataker, William Mackunis, Vladimir Golubev, Ron Efrati, Oksana Stalnov Jan 2024

On Progress In Exploring Controlled Viscous Limit-Cycle Oscillations In Modified Glauert Airfoil, Ethan Deweese, Lap Nguyen, Erik Vataker, William Mackunis, Vladimir Golubev, Ron Efrati, Oksana Stalnov

Publications

The paper reports on the progress in the development of a novel robust, nonlinear flow control technology that employs an array of synthetic-jet actuators (SJAs) embedded in 2-DOF, elastically mounted, optimized Modified Glauert (MG) airfoil design in order to control limit cycle oscillations (LCO) at low subsonic flow regimes. The focus here is on the conceptual design of the wind energy harvesting system that employs, e.g., a piezoelectric device to extract energy from plunging LCO, with the closed-loop controller being capable to sustain the required LCO amplitudes over a wide range of wind speeds. The current high-fidelity studies first include …


Experimental Environmental Profiles And Sloshing Dynamics Aboard Zero-G Aircraft, Pedro J. Llanos, Sathya Gangadharan, Kevin Crosby Jan 2024

Experimental Environmental Profiles And Sloshing Dynamics Aboard Zero-G Aircraft, Pedro J. Llanos, Sathya Gangadharan, Kevin Crosby

Publications

This study presents the results of a parabolic flight experiment to study the sloshing dynamics of the magneto-active propellant management device experiment. This device utilizes a magnetoactive membrane and magnets located external to the tank to effectively damp the liquid free surface motion. This research work establishes a benchmark with sloshing analytical formulation and sensor calibration methods that can be used to characterize future research parabolic flights while providing important environmental profiles measured during flight, such as accelerations, pitch angle, velocity, temperature, total volatile content, carbon dioxide, relative humidity, magnetic field, and radiation. Correlation between these flight variables and the …


Experimental Analysis Of The Integrated High-Lift Propulsor, Robert W. Deters, Byron Ward, Shreyas Narsipur Jan 2024

Experimental Analysis Of The Integrated High-Lift Propulsor, Robert W. Deters, Byron Ward, Shreyas Narsipur

Publications

Wind tunnel testing was conducted to evaluate the performance of the Integrated High Lift Propulsor (IHLP), a novel Distributed Electric Propulsion (DEP) system. The IHLP integrates traditional Krueger flap/slat elements with a Distributed Electric Propulsion design, enhancing high lift performance and cruise efficiency compared to conventional pylon-mounted DEP configurations. Starting from a baseline configuration determined from pretest Computational Fluid Dynamics (CFD) analyses, a parametric study was performed to determine the influence on the aerodynamic characteristics (���� , ����, and ����). The study involved variations in flap settings, slat angles, overlap, propeller tilt, and propeller position. The impact of Reynolds number, …


Dynamics Of A 3-D Inlet/Isolator Measured With Fast Pressure-Sensitive Paint, Andrew N. Bustard, Mark E. Noftz, Mitsugu Hasegawa, Hirotaka Sakaue, Joseph S. Jewell, Nicholas J. Bisek, Thomas J. Juliano Jan 2024

Dynamics Of A 3-D Inlet/Isolator Measured With Fast Pressure-Sensitive Paint, Andrew N. Bustard, Mark E. Noftz, Mitsugu Hasegawa, Hirotaka Sakaue, Joseph S. Jewell, Nicholas J. Bisek, Thomas J. Juliano

Publications

Fast pressure-sensitive paint (PSP) was applied to an inlet/isolator designed using the Osculating Internal Waverider Inlet with Parallel Streamlines (OIWPS) method. The dorsal isolator surface pressure was measured using anodized-aluminum PSP through transparent cast acrylic that makes up the ventral portion of the isolator. Temperature-sensitive paint was utilized to correct for the PSP’s temperature sensitivity. The model was tested under Mach 5.7 flow at Re = 8.5 ×106 /m and 10.2 ×106 /m in the AFOSR–Notre Dame Large Mach-6 Quiet Tunnel (ANDLM6QT) under conventional noise conditions. Flow phenomena, such as shocks originating in the inlet and flow separation at the …


Fundamentals Of Sustainability, Eva Maleviti Jan 2024

Fundamentals Of Sustainability, Eva Maleviti

Publications

Fundamentals of Sustainable Aviation is the frst textbook to survey the critical feld of sustainability within the aviation industry. Taking a systems thinking approach, it presents the foundational principles of sustainability and methodically applies them to diferent aviation sectors. Opening with the basics of sustainability, emphasising the Sustainable Development Goals, the book then considers the environmental, economic and social dimensions of aviation. The following chapters apply these insights to aviation design, supply chains, operations, maintenance and facilities. The fnal chapter examines the concept of resilience in sustainable aviation. Overall, the textbook shows how future sustainability can be achieved by making …


Flying To Net Zero With Sustainable Atos; Changing Cultures​, Eva Maleviti Nov 2023

Flying To Net Zero With Sustainable Atos; Changing Cultures​, Eva Maleviti

Publications

What is Sustainability?

  • World Commission on Environment and Development’s (WCED) 1987 Brundtland Report ‘’Our Common Future’’.
  • Help world nations towards sustainable development.

17 Sustainable Development Goals

  • The start of all industries are the 17 SDGs
  • Aviation can address the 15 SDGs
  • Net zero target suggest reduction of aviation emissions up to 21.2 Gt CO2


Sustainable Atos - Flying To Net Zero, Eva Maleviti, Bettina Mrusek Apr 2023

Sustainable Atos - Flying To Net Zero, Eva Maleviti, Bettina Mrusek

Publications

Pathways to Net Zero- Targets

Improve fuel-efficiency by an average of 2% per year - 2020 to 2030

Reduction in total carbon dioxide emissions to net-zero by 2050.

After 2026 carbon allowances will be zero for EU.


Adaptive Modified Rise-Based Quadrotor Trajectory Tracking With Actuator Uncertainty Compensation, Emmanuel Ogbanje Ijoga, William Mackunis, Krishna Bhavithavya Kidambi, Madhur Tiwari Mar 2023

Adaptive Modified Rise-Based Quadrotor Trajectory Tracking With Actuator Uncertainty Compensation, Emmanuel Ogbanje Ijoga, William Mackunis, Krishna Bhavithavya Kidambi, Madhur Tiwari

Publications

This paper presents an adaptive robust nonlinear control method, which achieves reliable trajectory tracking control for a quadrotor unmanned aerial vehicle in the presence of gyroscopic effects, rotor dynamics, and external disturbances. Through novel mathematical manipulation in the error system development, the quadrotor dynamics are expressed in a control-oriented form, which explicitly incorporates the uncertainty in the gyroscopic term and control actuation term. An adaptive robust nonlinear control law is then designed to stabilize both the position and attitude loops of the quadrotor system. A rigorous Lyapunov-based analysis is utilized to prove asymptotic trajectory tracking, where the region of convergence …


Air Traffic Management Principles: A Case Study On How To Create A Sustainable System, Eva Maleviti Jan 2023

Air Traffic Management Principles: A Case Study On How To Create A Sustainable System, Eva Maleviti

Publications

BEYOND ENVIRONMENTAL SUSTAINABILITY

  • Emissions, SAF, CORSIA, Design
  • Economic growth and development
  • Sustainability should go beyond environment
  • Non-technology approaches for sustainability and Net-Zero targets
  • What about social sustainability and people?

In the total share of aviation emissions (1GT CO2) 3% is 3Mt CO2. Small share but very significant contribution.


Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek Jan 2023

Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek

Publications

The design of an inward-turning, high-speed, three-dimensional streamline traced intake is presented from osculating axisymmetric theory. To satisfy the osculating intake design criteria, a stitched Busemann diffuser and Internal Conical Flow-A solution is used as the basic isentropic compressive streamline. This new contour provides efficient compression, high flow uniformity, and straight leading edge shocks of equal strength. Additionally, a novel method for constructing the inlet cowl is presented. The combined process leads to a new method of high-speed intake design. A generic shape-transitioned intake is constructed and named the Indiana Inlet for the Indiana universities that contributed to the project. …


A Machine Learning Approach Towards Analyzing Impact Of Surface Weather On Expect Departure Clearance Times In Aviation, Dothag Truong, Shlok Misra, Godfrey V. D'Souza Nov 2022

A Machine Learning Approach Towards Analyzing Impact Of Surface Weather On Expect Departure Clearance Times In Aviation, Dothag Truong, Shlok Misra, Godfrey V. D'Souza

Publications

Commercial air travel in the United States has grown significantly in the past decade. While the reasons for air traffic delays can vary, the weather is the largest cause of flight cancellations and delays in the United States. Air Traffic Control centers utilize Traffic Management Initiatives such as Ground Stops and Expect Departure Clearance Times (EDCT) to manage traffic into and out of affected airports. Airline dispatchers and pilots monitor EDCTs to adjust flight blocks and flight schedules to reduce the impact on the airline’s operating network. The use of time-series data mining can be used to assess and quantify …