This paper identifies key cognitive and human-automation challenges in the integration of Uncrewed Aerial Systems (UAS) and Advanced Air Mobility (AAM) through a thematic review of existing academic and industrial literature. Human Factors considerations in UAS-AAM differ from those in conventional aviation and require greater attention before wide deployment. This research provides a thematic review of cognitive and human-automation challenges, including Level of Automation (LOA), Human Automation Teaming and Trust (HAT2), Situational Awareness and Attention (SAA), Cognitive Overload and Distress (COD), Vigilance and Fatigue (VF), and Human Machine Interface and Interaction (HMI2). By highlighting these challenges, this study provides a foundational understanding to guide human-machine interface design, policy development, and future research in the evolving UAS and AAM landscape.

This paper explores the assessment of the impact of sustainability initiatives in six US small hub airports. A holistic approach with three phases — sustainability planning, implementation and monitoring — was employed to better understand how small hub airports gauge the success and impact of a sustainability initiative before implementation. The study objectives were twofold: (1) to gain an in-depth understanding of sustainability assessment methods and tools, and sustainability metrics and key performance indicators (KPIs) used to assess the impacts of sustainability initiatives in the three phases; and (2) to develop a preliminary sustainability impact assessment framework that incorporates impact assessment from the start of planning of sustainability initiatives. Researchers used multiple case study research methodology. Sustainability planning documents from six small hub airports were gathered and examined, followed by interviews with airport executives and airport planning consultants. The documents were analysed for each individual airport and the interviews were analysed thematically in aggregate. Findings show that the small hub airports studied have adopted sustainability practices in airport planning; however, there is no uniform approach for setting performance metrics and KPIs. Where used, monitoring of performance metrics and assessment of the impacts of sustainability initiatives is not clearly defined. In addition, small hub airport operators face various challenges in assessing the impacts of sustainability initiatives, including lack of a standardised assessment framework and lack of in-house sustainability experts. In addition, these airports operate with limited budgets, leading to human resources and financial constraints, leaving no budget for active monitoring of sustainability initiatives. Based on the findings of the study, researchers developed a framework for assessing the impacts of sustainability initiatives that may be used by airport operators to inform decision making on assessment of the impacts of sustainability initiatives. The proposed framework may be most applicable to small airports such as the ones in this paper. This article is also included in The Business & Management Collection which can be accessed at https://hstalks.com/business/.

Taxi time plays a critical role in airport capacity, aircraft fuel consumption, and emissions. It is defined as the time from touchdown to the gate and from the gate to liftoff. The International Civil Aviation Organization (ICAO) established a standard taxi/ground idle time-in-mode (TIM) of 26 min in the landing and take-off (LTO) cycle for modeling turbine engine aircraft emissions. However, actual taxi times vary significantly across airports. While a simplified standard streamlines emissions modeling, the 26 min assumption may not accurately reflect real-world conditions. While using airport-specific taxi times may not always be practical, hub classifications of U.S. commercial airports may affect taxi time and serve as a compromise between airport-specific taxi times and a simplified standard. Therefore, this study statistically analyzed Federal Aviation Administration (FAA) data from 71 U.S. commercial hub airports to compare reported taxi times with the ICAO’s standard and assess the influence of airport hub classifications. The exploratory findings indicate that the 26 min ICAO taxi/idle TIM does not represent reported taxi times at 70 of the 71 sampled airports. Moreover, total taxi time varied by hub classification: small-hub airports had a mean taxi time of 19.82 min (median: 18 min), medium-hub airports had a mean taxi time of 19.72 min (median: 18.25 min), and large hubs had a mean taxi time of 26.98 min (median: 25.08 min). When hub classifications were ignored, the overall mean taxi time was 23.78 min (median: 22 min), indicating a statistically significant difference between the ICAO’s standard 26 min assumption and the observed taxi times at most airports.

A high number of accidents during helicopter training in the United States (U.S.) highlights the need for research to investigate their causal and contributing factors. In this retrospective study, researchers analyzed helicopter instructional accidents reported in the National Transportation Safety Board (NTSB) Case Analysis and Reporting Online (CAROL) database. The Systems Theoretic Accident Model and Processes (STAMP) and Systems-Theoretic Process Analysis (STPA) methodologies were used to identify hazards and unsafe control actions in helicopter training, using autorotation maneuvers as a case study. Helicopter instructional flights in the U.S. accounted for 299 accidents between 2010 and 2022, with an average accident rate of 4.7 per 100,000 flight hours. Findings indicate that loss of control in flight (27.4%) and hard landings (19.4%) were the most prevalent accident-defining events. Autorotation-related accidents contributed to 27.1% of total cases. This study mapped control structures, identified unsafe control actions, and proposed systemic improvements to enhance safety through regulatory, training, and technological interventions. Recommendations include integrating Evidence-Based training (EBT), Flight Simulation Training Devices (FSTDs), and real-time feedback systems to reduce risks associated with autorotation training. Future research should expand the STAMP-STPA scope to additional operational factors, such as organizational culture and environmental conditions, to improve helicopter training safety.

Most weather-related accidents in General Aviation (GA) can be attributed to incorrect situation assessment and decision-making. The FAA’s Weather Technology in the Cockpit (WTIC) Program sponsors research to address these human factors challenges, which include introducing and evaluating new weather-related cockpit displays, mobile technologies, and applications by industry. In this session, a moderated panel will discuss ongoing WTIC-sponsored research projects being performed at different universities, aimed at understanding and addressing weather-related, GA issues. The projects relate to the (1) use of extended reality (XR) to enhance student pilot learning, (2) development of speech recognition technology to automate the pilot report (PIREP) submission process, and (3) assessment of pilot sensemaking and weather information usage in low altitude operations. The results of this collective work demonstrate ongoing and safety-focused research intended to support GA pilots through multiple stages of their flying experience.

A pilot weather report (PIREP) is a firsthand report of actual meteorological phenomena encountered by an aircraft in flight or on the ground. In general aviation (GA), PIREPs are a critical method of communicating weather information with pilots, controllers, and forecasters. However, GA pilots may find submitting PIREPs a cumbersome, manually intensive, and latent process. Automation of the radio PIREP submission process could lead to an increase in the quantity and quality (i.e., accuracy, timeliness, and usefulness) of GA PIREPs. This paper discusses the development and evaluation of a three-tier system to automatically convert spoken PIREPs to coded PIREPs using speech recognition, machine learning (ML), and natural-language-processing techniques. Specifically, this paper describes 1) the development, evaluation, and limitations of a trained commercial-of-the-shelf speech recognition system to generate text transcriptions of the spoken PIREPs, 2) an ML-based Named Entity Recognition model for segregating and labeling information from PIREP transcriptions, and 3) a final deterministic encoder to generate PIREP codes. If implemented in practice, this approach could significantly reduce interferences associated with submitting PIREPs, increase the number of PIREP submissions, improve the quality of PIREPs, and ultimately make flying safer for GA pilots.

Interactions with subject matter experts during student design activities is an idea embraced by many faculty as a crucial component of a design course. However, the process of involving experts is challenging and takes a significant amount time in a semester that is already packed with other course requirements and activities. Furthermore, meaningful interactions between students and experts requires that students be trained on interaction etiquette, preparation for interactions, and on responsible conduct of research. With other priorities demanding student and faculty time, organizing and conducting interactions between experts and students in design courses may be difficult to achieve. Research to understand the value of expert interactions may inform educators as to the pedagogical value, and provide support for including these activities in design courses. Graduate and undergraduate engineering and technology students from across the United States compete annually in the Airport Cooperative Research Program (ACRP) Design Competition, a national airport design competition. The competition requires a design submittal in one of four competition categories: airport environmental interactions, airport management and planning, airport operation and maintenance, and runway safety/runway incursions/runway excursions. One of the six competition goals is to inspire undergraduate and graduate students to develop solutions for real-world challenges facing airports and the National Airspace System (NAS). The competition rubric consists of a total of 130 points allocated to different sections with 12 points allocated for interactions with experts. These 12 points are divided equally for contacts with airport operators and with industry experts. It is important that these interactions occur prior, or during the design process, and not only at the end of the design package development. By analyzing the winning design packages, the researchers seek to understand the contributions of expert interactions before and during the design process, especially those that informed design choices, as reported by the student teams and their faculty advisors. The competition publishes the winning design proposals on the ACRP website. The 35 first-, second-, and third-place design packages from 2017 to 2020 were collected and analyzed using quantitative and qualitative research methods. From this data, themes are identified and specific examples are collected. The bias is reduced by the use of multiple researchers examining the student design proposals, and then comparing the results. Differences are documented and research team discuss the results to develop a consensus view. The authors are experienced in this design competition as faculty advisor and student team members. In addition to research results, a guide to interactions, how to find experts and engage them, and suggestions of the types of questions to ask are provided. A study of the perceptions of the contributions of interactions with experts in a design course may enhance understanding of the value that these interactions have on the educational experiences of students in design courses. Consequently, understanding the value of the interactions provides educators incentive to include expert interactions in design courses.

While sustainable aviation research has primarily focused on the airline industry, aircraft manufacturing, and airport responsibilities, the aircraft maintenance, repair, and overhaul (MRO) industry’s contribution to achieving sustainable aviation goals has been overlooked. This study examines the approaches to corporate sustainability practices used by aircraft MRO companies worldwide. The methodology used to investigate the sustainability actions of major MRO companies globally was mainly based on observational data gathered from multiple data sources, such as environmental, social, and governance (ESG) and investor relations documents. Four companies out of the 13 major MRO companies whose sustainability reports were found are examined as a case study analysis. Each MRO company adopted different definitions and practices of sustainability. The findings show that the aircraft MRO sustainability definition varies among the major companies studied, but some commonalities can be used to develop a proposed definition. The authors propose that aircraft MRO sustainability be defined as the ability to conduct MRO business that positively affects all stakeholders while emphasizing safety, quality, and integrity values, using technology and innovation to make growth, and constantly stabilizing and/or diminishing the impact on the environment. This study contributes to the understanding of sustainable aviation by highlighting the role of MRO companies in achieving sustainable goals.

Objective Helicopter air ambulance (HAA) services are essential to air medical transport in the United States. However, HAA accidents, incidents, and fatalities have been a reason for concern for HAA operations. This article analyzes the numbers, proportions, contributing or causal factors, and defining events of HAA accidents in the United States from 2010 to 2021. Methods The National Transportation Safety Board final investigation reports, defining events, findings, and summary data were analyzed for 83 HAA accidents in the United States from 2010 to 2021. The 2 proportions test was used to compare the proportions of fatal HAA accidents between 2010-2015 and 2016-2021. Results The data show that 21/47 (45%) of HAA accidents in 2010-2015 and 6/36 (17%) in 2016-2021 were fatal, representing a significant (P < .01) reduction in the proportion of fatal accidents in 2016-2021 from 2010-2015 time period. VFR encounter IMC events accounted for 9/47 (19%) of HAA accidents in 2010-2015 and 1/36 (3%) accident in 2016-2021, representing a significant (P < .05) reduction in VFR encounter IMC accidents. Conclusion There was a statistically significant decrease in the proportion of fatal HAA accidents from 2010-2015 to 2016-2021, which may be attributable to the changes in the regulatory framework, training protocols, safety awareness initiatives, and technological advancements to address HAA safety.

Hydrogen-fueled aircraft are a promising innovation for a sustainable future in aviation. While hydrogen aircraft design has been widely studied, research on airport requirements for new infrastructure associated with hydrogen-fueled aircraft and its integration with existing facilities is scarce. This study analyzes the current body of knowledge and identifies the planning challenges which need to be overcome to enable the operation of hydrogen flights at airports. An investigation of the preparation of seven major international airports for hydrogen-powered flights finds that, although there is commitment, airports are not currently prepared for hydrogen-based flights. Major adjustments are required across airport sites, covering land use plans, airside development, utility infrastructure development, and safety, security, and training. Developments are also required across the wider aviation industry, including equipment updates, such as for refueling and ground support, and supportive policy and regulations for hydrogen-powered aircraft. The next 5–10 years is identified from the review as a critical time period for airports, given that the first commercial hydrogen-powered flight is likely to depart in 2026 and that the next generation of short-range hydrogen-powered aircraft is predicted to enter service between 2030 and 2035.

As a result of the tremendous boost in computational power, the current prevalence of large bodies of data, and the growing power of data-driven algorithms, natural language processing (NLP) has recently experienced rapid progressions in multitudinous domains, one of which is aviation. In this study, we explore the current standing of NLP in aviation from the perspective of both research and industry. We identify safety reports analyses, aviation maintenance, and air traffic control as the three main focus areas of NLP research in aviation. We also list currently available NLP software and how they have been used in the aviation industry. Finally, we shed a spotlight on some of the existing challenges posed by the aviation domain on standard NLP techniques, discuss the current corresponding research efforts, and put forward our recommended research direction.

Aircraft operations statistics have typically received significant attention from U.S. airport owners and operators and state, local, and federal agencies. Accurate operational data is beneficial in assessing airports' performance efficiency and impact on the environment, but operational statistics at nontowered general aviation airports are, for the most part, limited or not available. However, the increasing availability and economy of capturing and processing Automatic Dependent Surveillance-Broadcast (ADS-B) data shows promise for improving accessibility to a wide variety of information about the aircraft operating in the vicinity of these airports. Using machine learning technology, specific operational details can be decoded from ADS-B data. This paper aims to develop a reliable and economical method for general aviation aircraft flight phase identification, thereby leading to improved noise and emissions models, which are foundational to addressing many public concerns related to airports.

The National Transportation Safety Board (NTSB) found that weather-related accidents involving GA aircraft that encountered poor visibility have the highest fatality rate among all types of accidents (NTSB, 2017). Pilot reports (PIREPs) are reports made by pilots concerning the weather conditions they experience during flight. PIREPs are one of the most important sources that provide in situ observations that can be used by pilots and others to avoid weather hazards. The Federal Aviation Administration (FAA) recommends pilots to submit at least one PIREP on each flight, regardless of whether the encountered weather is good or bad or match weather forecasts (NTSB, 2017). However, GA pilots submitted relatively fewer PIREPs compared to the volume of air traffic in the United States. Casner (2010) surveyed 189 GA pilots to examine 15 hypothesized factors that might influence the number of PIREPs submitted annually. The study reported that many pilots lack awareness of the importance of all PIREPs and usually do not feel that they have had enough training that focused on PIREP submission and weather conditions recognition. Pilots that felt they were “often too busy to file a PIREP” were also found to “tend to submit them less often” (Casner, 2010, p. 362). In addition, prior research funded through PEGASAS with the FAA Weather Technology in the Cockpit (WTIC) program office identified many barriers in the PIREP submission process that often lead to ‘No PIREP submission’. Examples of these barriers include not knowing how/where to submit a PIREP, not being aware of the importance of the PIREP, not getting training on PIREP submission, not being familiar with PIREP format, not knowing what to say to submit a PIREP, not being confident of weather assessment, and not having time to submit PIREP. The research team also found that there are trust-related gaps among GA pilots that affect PIREP submission. In an effort to reduce pilot workload and increase report accuracy, timeliness, and usefulness, we are seeking longerterm methods to automate PIREP submissions and thus reduce the need for hands-on communication. In particular, automated speech recognition technology represents a viable option for converting spoken phrases into text, which can then be used to create coded PIREPs. If implemented in GA, this approach could significantly reduce task interference associated with submitting PIREPs and make flying safer for pilots. The current research is part of a larger research project that aims to collect demographics, spoken PIREPs, and trustrelated PIREP information from GA pilots in order to develop such novel approaches to PIREP submissions. In this paper, we focus on and present the parts of the trust section that address PIREP submission. In contrast to Casner (2010), who examined submission factors and attempted to correlate pilot responses to these questions to their reported number of PIREPs, our survey asked trust questions related to PIREP submission and dissemination and to sources of PIREP information, in addition to an open-ended question. A Qualtrics® questionnaire was administered via the internet to various aviation organizations/communities, e.g., University Aviation Association (UAA), Aircraft Owners and Pilots Association (AOPA), Alaska Airmen Association, and Curt Lewis & Associates. In this survey, pilots were presented with custom visual representations of weather situations and asked to provide audio PIREP responses for each weather condition show. They were also asked to answer a set of trustrelated questions related to GA pilot perception and use of PIREPs. In total, 464 pilots across the United States participated. The research team collected 316 audio responses by the end of the study. The trust questions were answered by 161 participants. Overall, the majority of respondents (74%) reported being confident in knowing what to say over the radio when submitting a PIREP. A majority of participants (60%) reported that they submit fewer than five PIREPs per year. Six themes emerged from pilots’ responses when asked to comment on anything else related to PIREPs. These themes helped provide insight into pilot responses to other questions. Results from this study can inform training protocols and the development in next-generation technologies to support PIREP submission, and may ultimately contribute to improved safety for GA operations.

This study explores the techno-economic analysis of producing Camelina-derived Hydroprocessed Renewable Jet (HRJ) fuel in Montana using the hydro-deoxygenation (HDO) pathway. The HDO method requires added hydrogen and increases cost. The estimated breakeven price of Camelina-derived HRJ fuel generated from the HDO reaction follows the UOP Honeywell procedure. Oilseed cultivation, lipid extraction, and HRJ fuel production were evaluated to estimate the HRJ fuel breakeven price. In an extraction facility with annual processing capacity of 3000 Mg, the breakeven price of Camelina oil was $0.35 per liter over a 20-year operating period and $0.34 per liter over a 30-year period. For a 20-year operating period, the deterministic breakeven price of HRJ fuel was $0.87 per liter with a commercial hydrogen and $1.01 per liter when the plant generated its own hydrogen supply; a 30-year operating period had $0.02 per liter savings. The sensitivity analysis indicates a breakeven price between $0.87 and $1.44 per liter in a facility with an on-site hydrogen plant, and between $0.75 and $1.26 per liter when purchasing hydrogen. An additional $0.02 per liter of capital investment cost is incurred to produce HRJ fuel instead of renewable diesel. Depending on the fuel product, investors would have a capital cost penalty of $0.13 to $0.15 per liter for producing hydrogen on-site.

End-around taxiways (EAT) have been implemented at four major U.S. airports to increase the safety and throughput of parallel runway systems. This paper proposes two new runway and taxiway choices that become possible because of EATs. Instead of using the inboard runway to take off, the departing aircraft could use the outboard runway and use the EAT as the taxi-out path. A discrete-event stochastic simulation model simulates the operations of four different runway and taxiway choices. Two experiments compare the performance of the four choices on average taxi times, average fuel consumption per taxi, and number of runway crossings. In general, the results indicate that using the outboard runway to take off and the EAT as a taxi-out path would yield benefits in both taxi-in and taxi-out performance, as well as enhancing runway safety. Using the outboard runway to land and the EAT as a taxi-in path would yield benefit in taxi-out performance and runway safety at the expense of a longer taxi-in time. Concerns related to using the EAT as the taxi-out path, as well as potential future research topics, are discussed.

Airports have economic, environmental, and social impacts on communities. Many of these impacts are influenced by airport management decisions. Airport sustainability may be thought of as having four primary areas: environmental, economic, operational, and social. The objective of this study is to understand better the adoption of social sustainability practices in small hub airport planning in the United States. The small hub airports in this study participated in the Federal Aviation Administration Airport Improvement Program for sustainability planning and have published their sustainability plans as either standalone sustainability management plans or integrated sustainable master plans. Plans from the six airports were gathered and examined as part of an exploratory case study analysis. The findings show that small hub airports do not use the same framework or select the same practices for social sustainability. Social sustainability practices for these six small hub airports focus on four stakeholder categories: passengers and travelers, employees, communities and local businesses, and concessionaires and tenants.

Improving operational sustainability may help U.S. general aviation (GA) airports improve overall sustainable development without substantial financial inputs. An exploratory multiple-case study of five GA airports was conducted to explore the current understandings of airport operational sustainability among U.S. GA airports. Based on findings, a new definition of airport operational sustainability for U.S. GA airports was developed. A set of performance metrics for measuring operational sustainability in U.S. GA airports was identified. The new definition may help GA airports to develop sustainable management plans, and may help airports in other categories to expand their sustainability perspectives. The metrics identified in this study may be used to measure progress to the sustainable development, identify problems, and set performance goals or targets for airports.

Brazil is the largest country in Latin America and has a considerable amount of air traffic volume domestically and internationally. Wildlife strikes are an increasing safety and economic concern for aviation operations in Brazil. The Brazilian Aeronautical Accidents Investigation and Prevention Center (CENIPA) has published annual reports summarizing the results of analyses of the data in a national level since 2009. The goal of this study was to supplement the CENIPA's annual reports with information derived from the analysis of wildlife strikes to aviation, during 2011-2016, from the three busiest international commercial airports in Brazil: Guarulhos, Brasília, and Galeão. A set of descriptive analysis was conducted to present the overall characteristics of wildlife strikes at and around those three airports. In addition, statistical comparison of wildlife strikes with different factors was conducted. Analysis of these data indicated an increasing trend of wildlife strikes from 2011 to 2016. Results also indicated that the majority of the damaging strikes occurred during the departure phases of flight at the studied airports. The distributions of wildlife-strikes per phase of flight, per quarter of the year, per type of operator, and per period of the day are presented in this paper. Results indicated that, during the period studied, most strikes in Guarulhos occurred during the first, and in Brasília and Galeão during the second quarter of the year, respectively. Findings suggested that the risk of a damaging strike is higher at dawn in Guarulhos and Galeão, and during the day in Brasília. Findings of this study could facilitate the integration of Safety Management Systems (SMS) and wildlife hazard management programs (WHMP) by airport operators and air carriers. Additionally, current findings may inform the development of national policies and standards in Brazil as well as the future integrated research and management efforts to mitigate wildlife strikes.

The number of annual aircraft operations (take-offs and landings) is a significant concern to both airport owners and operators and to governmental agencies because operations data are one of the most important criteria used for determining future investments in airports. However, estimating the number of aircraft operations at non-towered general aviation airports is challenging work due to the lack of counts from air traffic control towers or useful estimates developed using models. Previous work in estimating annual aircraft operations has resulted in models and sampling methods that are imprecise or difficult to use. In 2014, new classification categories of 2,939 public-use general aviation airports in the United States were published in the National Plan of Integrated Airport Systems (NPIAS) 2015-2019 Report. The goal of this research is to determine if the new airport classification categories provide an opportunity to improve models for estimating aircraft operations at GA airports. This research used the FAA Form 5010 data reported by airport managers. Another potential source for operations is the TAF (Terminal Area Forecast). Both Form 5010 and TAF have inaccuracies for non-towered airports. The Form 5010 was selected because it is one of the sources for the TAF. Based on this study, the NPIAS categories were found to be significant in the regression model developed. Future research will investigate using TAF data.