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TERRA LUNARIS: Assessment of a Lunar Habitat for Scientific Astronauts, Space Miners, or Space Tourists
Get PDFThis 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 scenarios from different perspectives, offering recommendations tailored to each characteristic group. The findings indicate that the hybrid design of the Terra Lunaris concept—combining fixed and inflatable components—is particularly advantageous for the lunar scenario considered. Additionally, the study suggests that the concept is also a viable option for Mars, although a fully fixed habitat may be slightly preferable in that context
Airport Sustainability: Balancing Operational and Environmental Objectives
No full textSolar power is a frequently used strategy to support green power generation at airports and near airports. Further, all U.S. airports that published ESG reports included solar power as a strategy. Many of these airports utilize solar power to help meet UN SDGs. While solar power provides numerous advantages, in the vicinity of airports it can also present potential risks. This was most recently observed at Amsterdam Schiphol Airport, where nearly half of the panels at a nearby solar farm will be removed due to problems with glare affecting pilots on approach. This research investigates the use of solar power at airports to support UN SDGs and explores when solar may not be appropriate near airports, as well as possible mitigation strategies
Insights from ERAU\u27s Operation of the Pipistrel Velis Electro
No full textThis presentation provides an inside look at Embry-Riddle Aeronautical University’s operational experience with the Pipistrel Velis Electro. Over the past year, I have logged more than 30 flights in the aircraft and had the opportunity to serve as both the initial pilot trained by the delivery team and as an instructor qualifying three additional pilots. This opportunity has offered firsthand insights into the practical challenges and opportunities associated with introducing an electric airplane into a flight training environment. The presentation will focus on the process of adapting established maintenance and operational procedures to support electric aircraft operations to gain operational insight into possible adoption of electric aircraft and fleet integration in the future. Operationally, the Velis Electro offers several advantages that align with ERAU’s sustainability and innovation goals. Its quiet noise levels and impressive climb performance are beneficial for noise-sensitive environments. However, these benefits are balanced by limitations, particularly their constrained endurance and the logistical challenges of operating in a high-traffic environment. These factors required strategic planning to integrate the aircraft into the University’s daily operations and to ensure opportunities to gather information while maintaining a high level of safety. Beyond technical performance, this presentation will share survey feedback from students, instructors, staff, and faculty who experienced flights in the Velis Electro. Ultimately, the goal is to inform how electric aircraft can be incorporated into existing flight programs, offering a foundation for both operational sustainability and continued innovation in flight training
Aviation’s Net-Zero Emission Goals of 2050: U.S. Travelers’ Perspectives
No full textIn 2021, the United States released the Aviation Climate Action Plan, its first roadmap for achieving net-zero aviation emissions by 2050. The plan outlines policies to advance sustainable aviation through collaboration among manufacturers, airlines, fuel providers, air traffic controllers, and airports. Achieving such ambitious goals will require substantial effort. However, while policy actions have been widely discussed, limited attention has been given to public perspectives on the plan, and it remains unclear how U.S. travelers view the net-zero emission goals. This study examined U.S. travelers’ perspectives and intentions regarding aviation’s net-zero emission goals. Specifically, it (1) investigated whether attitudinal, normative, environmental, and policy factors influence the perceived achievability of the 2050 goals; (2) evaluated travelers’ perceptions of goal relevance and their intentions to support these goals; and (3) assessed how these factors shape travelers’ willingness to take voluntary actions that contribute to emission reduction. To address these questions, six predictors—attitudes, subjective norms, government leadership, environmental self-identity, information availability, and perceived relevance—were analyzed for their effects on perceived goal achievability and the intention to fly less. Data were collected from U.S. travelers using convenience sampling and analyzed with structural equation modeling (SEM). Results show that attitudes, subjective norms, government leadership, perceived relevance, and environmental self-identity significantly influenced perceived achievability and intentions to reduce air travel. Further analysis revealed that U.S. travelers were influenced primarily by external factors, with government leadership and information availability emerging as the strongest predictors
Drone Noise, Local Action, and Federal Power
No full textDrones make noise. Of course, drone noise is quite different from traditional aircraft noise. But increasingly residents in neighborhoods across the country are taking notice of the high-pitched buzzing sounds drones emit as they deliver packages and are flown recreationally. While not all are bothered by the buzzing, to some, drone noise is annoying and concerning.
What to do? Noise is an area traditionally left to state and local government control. And given the extent to which perspectives diverge on just how problematic drone noise is, one may reasonably think its regulation should fall to the states or, perhaps better yet, local authorities. But how does this approach fit in with the federal government\u27s well-established authority to regulate aircraft noise and drone operations in general? Based on an article published in the Journal of Air Law and Commerce in 2024, this presentation explores this preemption question and challenges associated with drone noise regulation. Many issues raised by civilian drone operations are overshadowed by debates about the extent of federal preemption. Noise is no exception. This presentation shows that on the noise issue, the Supreme Court and lower courts\u27 precedent favor regulation at the federal level
Improving Erosion Resistance and Revegetation of Wildfire-Altered Soils Using Microbial Induced Calcite Precipitation
Get PDFClimate change is causing wildfires to occur more frequently and with higher intensity. Leading to wide range of impacts on agriculture, infrastructure, and the environment. Wildfires affect soils by burning their organic matter, resulting in an immediate deplete of nutrients and a significant reduction in nitrogen level. Wildfires also alter soils’ physical properties and make them less resistant to erosion which results in debris flows when wildfire are followed by a rainfall event. The reduced activity of microorganisms that aid in nutrient absorption makes the soil less effective in supporting plant life. Microbial Induced Calcite Precipitation (MICP) was found to be a sustainable treatment method for enhancing soil stability and reducing erodibility. MICP employs naturally existing microorganisms to precipitate calcium carbonate, which binds soil particles together. However previous studies mainly focused on using sporosarcina in regular soils, not in post-fire conditions. Further research is necessary to assess its effectiveness in soils affected by wildfires. In this research study, MICP was used to treat burned soil, where the efficacy of the treatment was measured by testing the treated samples for their shear strength, erodibility resistance and plants capacity to support vegetation. Soil samples were collected and burned to simulate wildfire conditions. The soil was mainly sandy, with a small percentage of fines and an organic content of 5-7%. Test results showed that the burned soils had decreased shear strength and erosion resistance compared to unburned natural soil. Shear strength was evaluated using Direct Shear test, erodibility was assessed with an erosion box that was designed for this research, under two different water heights of 37 and 18 cm. The improvement in vegetation recovery plant growth was evaluated based visually on the MICP treatment. For burned samples, the friction angle was reduced from 35- 38° to 23°, and erosion rates increased from 0.21-0.22 mm/sec to 0.87-0.91 mm/sec at a water height of 37 cm, and from 0.23-0.25 mm/sec to 0.79-0.87 mm/sec at an 18 cm water height. MICP treatment resulted in an increase in friction angle up to 36° after one-week treatment, and up to 37° after two- week treatment. After one week of treatment, erosion rates decreased to 0.2-0.23 mm/sec and 0-0.3 mm/sec at water heights of 37 cm and 18 cm, respectively. After two weeks of treatment, erosion decreased to negligible rates at both water heights. These results suggest that the MICP treatment can be considered a sustainable method for stabilizing wildfire-affected soils, improving their shear strength, erosion resistance and vegetation recovery. Future efforts will focus on optimizing the MICP treatment protocol targeted for large-scale sections and field implementation
Retention Rate of the Human Performance Course in Flight Training
Get PDFPilots are obliged to accurately assess a situation that poses a risk to flight safety and take the necessary corrective action. The theoretical knowledge in flight training is essential to accomplish this. The objective of the study is to ascertain the retention rate of the human performance (HP) course and to determine the necessity of refresher training. Sixteen questions were prepared for pre- and post-tests about the atmosphere, hypoxia and hyperventilation, barotrauma, and spatial disorientation. After completion of the pre-test, participants were instructed to watch the online training video covering the same HP subjects, and finally, a post-test was administered to evaluate the achievement of the training. Seventy-five percent or higher scores were accepted as successful. Thirty-three pilots participated in this study. The mean score of the post-test was higher than the pre-test (p \u3c 0.001). Sixty-three percent of the pilots were successful in the pre-test, and the success rate increased to 87.9% in the post-test (p = 0.011). This study demonstrated that human performance refresher training will be beneficial to increase the retention rate of essential information in flight physiology and will contribute to aviation safety
Developing Fixed-Bias Langmuir Probes for Multi-Point Constellation Deployments
Get PDFSince their initial development in the early 20th century, electrostatic Langmuir probes have proved invaluable in terrestrial and interplanetary ionospheric sounding applications. When deployed aboard rocket and satellite platforms, these probes yield high-cadence, in-situ measurements of key plasma parameters such as electron density, ion density, and electron temperature. Furthermore, the efficacy of Langmuir probes in characterizing the three-dimensional structure and dynamics of ionospheric plasmas can be augmented by the technique of multi-payload deployments. In this work, we discuss the design, development, and analysis of fixed-bias Langmuir probes constructed for two multi-point science campaigns: the Mars-bound, dual-satellite Escape and Plasma Acceleration and Dynamics Explorers (ESCAPADE) mission and the Sporadic E ElectroDynamics Demonstration (SpEED Demon) sounding rocket (launched on August 24, 2022). We begin with a basic treatment of the relevant background material, including ionosphere fundamentals and Langmuir probe theory. Next, we discuss the development process of the ESCAPADE Langmuir Probe (ELP) suite, highlighting the motivating design principles, instrument hardware, and pre-flight calibration. The process of radiation tolerance assurance for the ELP is considered in further detail; however, as the ESCAPADE satellites have yet to take flight, we follow this discussion with a presentation of data from the SpEED Demon deployable subpayloads, noting potential mechanisms for the density structures and irregularities which were observed during flight. Finally, we conclude with a brief summary and discussion of future work
Robust Spacecraft Autonomy for Deep Space Exploration in Special Euclidean Group SE(3)
Get PDFOver the past half-century, humanity has gained extensive experience conducting manned spaceflight near Earth. Arguably, near Earth could even include the Moon — the most distant destination humans have reached. However, near in this work primarily refers low Earth orbit (LEO). One could argue that we have not truly left Earth since the Apollo, as spacecraft in some LEOs remain subject to atmospheric drag thus emphasizing their continued connection to Earth\u27s immediate environment. Reflecting on this, it becomes clear that humanity has largely remained bound to Earth’s immediate vicinity since the Apollo missions reached the Moon. However, that is set to change. As of this writing, the Artemis II mission is gearing up to launch, carrying astronauts further from Earth than ever before. This milestone alone is a significant achievement, but the ambitious goals of the Artemis program and the Moon-to-Mars campaign bring forward an array of new challenges. For scientists and engineers who are designing these missions, these challenges highlight the complexity and excitement of venturing beyond what we know.
Many of these challenges revolve around autonomy. It is unrealistic to expect a pilot to physically man the joystick of a spacecraft during the vast majority of its mission, and the distances are simply too vast, and speeds too great for human reaction time, regardless of how augmented those human operators may be. Instances of direct human control during interplanetary flight are rare and generally limited to atmospheric reentry or manual override scenarios. When considering objectives such as moving cargo between distant points in space, performing proximity operations and docking in arbitrary orbits, and navigating and landing on celestial bodies without spaceports, communications infrastructure, or landing lights and with unknown surface properties, robust autonomy transitions from a luxury to a mission-critical requirement.
Legacy deep-space guidance, control and navigation (GN&C) methods, which rely heavily on ground-based sequencing schemes, are intolerant to unplanned events or off-nominal scenarios. Some examples of these include the Mars Climate Orbiter, which plunged to its destruction due to human error, specifically a confusion between SI and imperial units; the loss of Israel\u27s Beresheet lander due to a loss of communications with ground stations and a lack of onboard autonomy; the near-loss of the CAPSTONE mission due to a stuck thruster and an inability to perform onboard fault detection and isolation; the recent loss of the ispace HAKUTO-R lander due it misidentifying a faulty sensor that was actually providing correct elevation data, leading to it hovering thousands of feet above the lunar surface until fuel was depleted and it plunged to its destruction. What these missions have in common is that all of them could have been spared these hardships if the spacecraft had been equipped with more robust onboard autonomy and the ability to make its own decisions in the absence of valid commands from ground stations.
Implementing this capability, however, presents several significant technical challenges. Computational limitations of flight-proven systems and the challenge of developing and proving more capable, radiation-hardened equipment are significant bottlenecks. Equally important, however, is the development of theoretical methodology that can handle the numerous constraints of real spaceflight. One approach begins by considering the special Euclidean group SE(3). SE(3) is a smooth manifold and Lie group representing the space of 3-dimensional rigid-body transformations, comprising of a semidriect product of SO3 (rotations) and (translations). This formulation is especially advantageous during scenarios in which there is an unavoidable nonlinear coupling between translational and rotational motion. Examples of these scenarios are vehicles experiencing solar radiation pressure, gravity gradient torques, and relative motion problems such as rendezvous, proximity operations, and docking. SE(3)\u27s use of rotation matrices avoids the singularities of Euler angles and the unwinding issues associated with quaternion representations.
Recent work has explored these benefits within the geometric mechanics framework, demonstrating that robust filtering is possible using an unscented Kalman filter (UKF) on SE(3) and its tangent bundle \TSE. Furthermore, a novel filtering method in the field of rigid body dynamics, the discriminative Kalman filter (DKF), has also been developed on SE(3), and extended to include discriminative methods using the unscented transform, called the discriminative unscented Kalman filter (DUKF). It has been demonstrated in simulations that these methods are effective for spacecraft GN&C even in the presence of large measurement and process noise. This has been taken a step further - in the estimation of not only of states, but of parameters such as mass properties and moments of inertia, and even components of dynamical environments such as gravitational parameters and nonspherical elements.
As these methods have been developed over the last five years, simplifying assumptions have been relaxed, and an increasing degree of realism has been worked into the simulations. This has provided a necessary bridge between theory and application as we prepare to test some of the methods discussed herein on flight hardware - namely JAXA\u27s HTV-X spacecraft and the Dragon XL deep space logistics vehicle. Both of these vehicles must consider of not only mass property uncertainties, but also the changing values of those mass properties. Circumstances such as fuel depletion, slosh dynamics, and oscillations of solar panels and antennae may cause the controller currently used in this field to become unstable. To address these and other challenges, an extension of a Morse-Lyapunov controller to consider tracking control, changing mass properties, and even thermal loads is demonstrated herein.
This thesis introduces a framework for the implementation of autonomous guidance, navigation, and control for spacecraft systems in the presence of broad state and parameter uncertainties. It introduces a methodology for the estimation of states, parameters, and even dynamic environments, and a method for simultaneous control of all six degrees of freedom even in the presence of those uncertainties. This work does not claim universality, but rather provides a robust set of tools applicable across a wide range of realistic scenarios. A skilled engineer may apply these tools to achieve the results they seek with only some gain tuning, a set of broad yet realistic assumptions, and a solid understanding of their measurement model
How Does Climate Change Affect the Bird Migration Season and Number of Bird Strikes?
Get PDFWhile it is wildly accepted that climate change has led to a shift in bird migration seasons and patterns, how does this change affect the occurrence of strikes between birds and aircraft? Analysing bird strike data from the FAA\u27s Wildlife Strike Database and average annual temperature variations in the United States, we seek to find out if climate change has had an impact on bird strikes between 1990 and 2015 using multiple linear regression. Understanding the wider effects of climate change on the daily operation of aircraft would highlight if there were a need to update wildlife hazard management methods, with an end goal of promoting safety, reducing financial loss and environmental protection