Models of Aviation Noise Impact in the Context of Operation Decrease at Tan Son Nhat Airport.

Air traffic bans in response to the spread of the coronavirus have changed the sound situation of urban areas around airports. This study aimed to investigate the effect of this unprecedented event on the community response to noise before and after the international flight operation at Tan Son Nhat Airport (TSN) in March 2020. The "before" survey was conducted in August 2019, and the two "after" surveys were conducted in June and September 2020. Structural equation models (SEMs) for noise annoyance and insomnia were developed by linking the questionnaire items of the social surveys. The first effort aimed to achieve a common model of noise annoyance and insomnia, corresponding to the situation before and after the change, respectively. Approximately, 1200 responses were obtained from surveys conducted in 12 residential areas around TSN in 2019 and 2020. The average daily flight numbers observed in August 2019 during the two surveys conducted in 2020 were 728, 413, and 299, respectively. The sound pressure levels of the 12 sites around TSN decreased from 45-81 dB (mean = 64, SD = 9.8) in 2019 to 41-76 dB (mean = 60, SD = 9.8) and 41-73 dB (mean = 59, SD = 9.3) in June and September 2020, respectively. The SEM indicated that the residents' health was related to increased annoyance and insomnia.

Scenarios for a post-COVID-19 world airline network.

The airline industry was severely hit by the COVID-19 crisis with an average demand decrease of about 64 % (IATA, April 2020), which triggered already several bankruptcies of airline companies all over the world. While the robustness of the world airline network (WAN) was mostly studied as a homogeneous network, we introduce a new tool for analyzing the impact of a company failure: the "airline company network" where two airlines are connected if they share at least one route segment. Using this tool, we observe that the failure of companies well connected with others has the largest impact on the connectivity of the WAN. We then explore how the global demand reduction affects airlines differently and provide an analysis of different scenarios if it stays low and does not come back to its pre-crisis level. Using traffic data from the Official Aviation Guide and simple assumptions about customer's airline choice strategies, we find that the local effective demand can be much lower than the average one, especially for companies that are not monopolistic and share their segments with larger companies. Even if the average demand comes back to 60 % of the total capacity, we find that between 46 % and 59 % of the companies could experience a reduction of more than 50 % of their traffic, depending on the type of competitive advantage that drives customer's airline choice. These results highlight how the complex competitive structure of the WAN weakens its robustness when facing such a large crisis.

Evaluation of the impact of Covid-19 on air traffic volume in Turkish airspace using artificial neural networks and time series.

In early 2020, the aviation sector was one of the business lines adversely affected by the Covid 19 outbreak that affected the whole world. As a result, some countries imposed travel restrictions. Following these restrictions, air traffic density has decreased significantly worldwide. Since air traffic density directly affects almost all operations in air transportation, analyzing these data is very essential. For this purpose, SARIMA models, one of the linear time series models, and multilayer perceptron model (MLP), one of the artificial neural network methods suitable for nonlinear modeling, were applied to the air traffic data regarding Turkish airspace between 2010 and 2019, and the actual air traffic density was compared with the forecasts obtained from these analyses. It is considered that the results of this study are essential for organizations conducting aviation operations to take into consideration while doing future planning.

Uncertainty quantification of CO2 emissions from China's civil aviation industry to 2050.

To mitigate aviation's carbon emissions of the aviation industry, the following steps are vital: accurately quantifying the carbon emission path by considering uncertainty factors, including transportation demand in the post-COVID-19 pandemic period; identifying gaps between this path and emission reduction targets; and providing mitigation measures. Some mitigation measures that can be employed by China's civil aviation industry include the gradual realization of large-scale production of sustainable aviation fuels and transition to 100% sustainable and low-carbon sources of energy. This study identified the key driving factors of carbon emissions by using the Delphi Method and set scenarios that consider uncertainty, such as aviation development and emission reduction policies. A backpropagation neural network and Monte Carlo simulation were used to quantify the carbon emission path. The study results show that China's civil aviation industry can effectively help the country achieve its carbon peak and carbon neutrality goals. However, to achieve the net-zero carbon emissions goal of global aviation, China needs to reduce its emissions by approximately 82%-91% based on the optimal emission scenario. Thus, under the international net-zero target, China's civil aviation industry will face significant pressure to reduce its emissions. The use of sustainable aviation fuels is the best way to reduce aviation emissions by 2050. Moreover, in addition to the application of sustainable aviation fuel, it will be necessary to develop a new generation of aircraft introducing new materials and upgrading technology, implement additional carbon absorption measures, and make use of carbon trading markets to facilitate China's civil aviation industry's contribution to reduce climate change.

A novel resilience analysis methodology for airport networks system from the perspective of different epidemic prevention and control policy responses.

As the COVID-19 pandemic fades, the aviation industry is entering a fast recovery period. To analyze airport networks' post-pandemic resilience during the recovery process, this paper proposes a Comprehensive Resilience Assessment (CRA) model approach using the airport networks of China, Europe, and the U.S.A as case studies. The impact of COVID-19 on the networks is analyzed after populating the models of these networks with real air traffic data. The results suggest that the pandemic has caused damage to all three networks, although the damages to the network structures of Europe and the U.S.A are more severe than the damage in China. The analysis suggests that China, as the airport network with less network performance change, has a more stable level of resilience. The analysis also shows that the different levels of stringency policy in prevention and control measures during the epidemic directly affected the recovery rate of the network. This paper provides new insights into the impact of the pandemic on airport network resilience.

The effect of COVID-19 on self-reported safety incidents in aviation: An examination of the heterogeneous effects using causal machine learning.

INTRODUCTION: Disruptions to aviation operations occur daily on a micro-level with negligible impacts beyond the inconvenience of rebooking and changing aircrew schedules. The unprecedented disruption in global aviation due to COVID-19 highlighted a need to evaluate emergent safety issues rapidly. METHOD: This paper uses causal machine learning to examine the heterogeneous effects of COVID-19 on reported aircraft incursions/excursions. The analysis utilized self report data from NASA Aviation Safety Reporting System collected from 2018 to 2020. The report attributes include self identified group characteristics and expert categorization of factors and outcomes. The analysis identified attributes and subgroup characteristics that were most sensitive to COVID-19 in inducing incursions/excursions. The method included the generalized random forest and difference-in-difference techniques to explore causal effects. RESULTS: The analysis indicates first officers are more prone to experiencing incursion/excursion events during the pandemic. In addition, events categorized with the human factors confusion, distraction, and the causal factor fatigue increased incursion/excursion events. PRACTICAL APPLICATIONS: Understanding the attributes associated with the likelihood of incursion/excursion events provides policymakers and aviation organizations insights to improve prevention mechanisms for future pandemics or extended periods of reduced aviation operations.

Fatigue during Long-Haul Flights of Different Crew Compositions under Exemption from Layover and Flight Time during COVID-19.

Pilot fatigue and alertness are critical for civil aviation safety. Intercontinental pilots are more prone to fatigue and sleepiness due to jet lag, prolonged workdays, and disrupted rhythms. The Civil Aviation Administration of China excused enlarged flight crews from mandatory layovers and reimposed flight duration restrictions during COVID-19. This study investigates the sleep quality and attentional performance of pilots on intercontinental flights. The fifteen pilots who performed intercontinental flights in different crew compositions wore a body movement recorder, which has been proven to accurately estimate sleep duration and sleep efficiency. The crew's attentional performance and self-report were monitored at specified flight phases. In conclusion, the larger crews slept longer and more efficiently on board, particularly pilots in charge of takeoff and landing responsibilities. Crews on four-pilot layover flights were more alert before the takeoff of the inbound flights than exempt flights, but there was no significant difference towards the end of the mission. The new long-haul flight organization did not result in fatigue or decreased attention in the pilots. This study expands on the research by validating a novel intercontinental flight operation model under the COVID-19 scenario and highlighting critical spots for future fatigue management in various crew compositions.

Cardiovascular Concerns from COVID-19 in Pilots.

BACKGROUND: Cardiovascular disease, now complicated by the COVID-19 pandemic, remains a leading cause of death and risk for sudden incapacitation for pilots during flight. The capacity for aeromedically significant cardiovascular sequelae with potentially imperceptible clinical symptoms elicits concern both during and following resolution of acute COVID-19 in pilots.OBJECTIVE: We summarize the current state of knowledge regarding COVID-19 cardiovascular implications as applied to the aviation environment to better understand their significance toward flight safety and application toward a focused cardiovascular screening protocol following recovery from infection.METHODS: A narrative review of the cardiovascular implications of COVID-19 infection was performed using the PubMed literature search engine and existing organizational guidelines. In addition, to established medical aviation benchmarks, surrogate populations examined included high performance athletes (as a correlate for high G-forces), and scuba divers (as an environmental work analog). Conditions of primary concern included myocardial injury, proarrhythmic substrates, risk of sudden death, myopericarditis, pulse orthostatic lability in response to vigorous activity, cardiovagal dysfunction, and thromboembolic disease.LITERATURE REVIEW: Cardiovascular screening guideline recommendations post-infection recovery are suggested based on profile stratification: airperson flight class, tactical military, and aerobatic pilots. This provides an approach to inform aeromedical decision making.CONCLUSION: Aviation medical examiners should remain cognizant of the clinically apparent and occult manifestations of cardiovascular dysfunction associated with COVID-19 infection when applying return-to-work screening guidelines. This will ensure high flight safety standards are maintained and sudden incapacitation risk mitigated during and following the ongoing pandemic.Elkhatib W, Herrigel D, Harrison M, Flipse T, Speicher L. Cardiovascular concerns from COVID-19 in pilots. Aerosp Med Hum Perform. 2022; 93(12):855-865.

Greening aviation in era of COVID-19: Towards conceptualizing and operationalizing decarbonization.

Although net-zero greenhouse gas emission targets continue to gather burgeoning streams of research, there is a lacuna in current literature on the pathway challenges towards operationalizing decarbonization. The study advanced 2 × 2 matrix of an organizing framework of challenges in accomplishing net-zero emissions targets. Using the global airline industry as an illustrative context, the study provided deep insights on the pivotal industry, institutional, and organizational challenges in the era of COVID-19 such as fleet modernization, over-reliance on fossil fuel, slow progress in the development of hydrogen and electric aircraft, risk of corporate greenwashing, and divergent approaches adopted by airlines. The challenges can be classified into policy-oriented, organization-specific, and external/macro-environment factors. The contributions to theory and practices were identified and examined.

Forecasting crew fatigue risk on international flights under different policies in China during the COVID-19 outbreak.

To predict the risk of fatigue for flight crews on international flights under the new operating model policy of the civil aviation exemption approach policy during the COVID-19 outbreak, and to provide scientific validation methods and ideas for the exemption approach policy. This paper uses the change in flight crew alertness as a validation indicator, and then constructs an alertness assessment model to predict flight crew fatigue risk based on the SAFTE model theory. Then, the corresponding in-flight rotation plans for the flight is designed according to the exemption approach policy issued by the CAAC, the CCAR-121 part policy and the real operational requirements of the airline, respectively, and finally the simulation results is compared by comparing the pilot alertness and cockpit crew alertness under the exemption approach policy and the CCAR-121 part policy with the flight duration. The results show that the flight crew alertness level for the flight in-flight rotation plan simulation designed under the exemption approach policy is higher or closer to the pilot alertness level for operational flights under the CCAR-121 Part policy. This validates the reasonableness and safety of the exemption approach policy issued by the CAAC to meet the requirements of epidemic prevention and control, and provides scientific support and solutions for fatigue monitoring and management.

Quantitatively evaluate the impact of domestic aviation control measures on the spread of COVID-19 in China.

To quantitatively evaluate the impact of domestic aviation control measures on the spread of COVID-19 in China. The number of international flights from March to September 2019 simulated the number of flights from March to September 2020 without implementing aviation control measures. In addition, the proportion of asymptomatic persons and the delay in case reporting were adjusted to estimate the prevalence of each country during the same period and calculate the estimated imported cases. The estimated imported cases were assigned each day with weight, and the estimated daily reported cases were obtained based on the actual daily number of domestic cases in China. Effective Reproduction Number ([Formula: see text]) was calculated based on delayed distribution, Basic Reproductive Number ([Formula: see text]) distribution, and generation time distribution were reported in previous studies. Gaussian Process was used to estimate the effect of time-varying on [Formula: see text], and the estimated [Formula: see text] was compared with the actual [Formula: see text]. The estimated imported cases increased significantly compared with the actual number of imported cases. The estimated imported cases were mainly concentrated in North America and Europe from March to April and gradually increased in many East Asian countries from May to September. The difference between predicted [Formula: see text] and actual [Formula: see text] was statistically significant. The estimated imported cases and the estimated [Formula: see text] have increased compared to the actual situation. This paper quantitatively proves that Chinese aviation control measures significantly suppress the COVID-19 epidemic, which is conducive to promoting and applying this measure.

[Analysis of the stressors and mental status of civil aviation pilots under the background of the major infectious disease].

Objective: To study the stressors and mental status of civil aviation pilots under the background of major infectious disease. Methods: From January to March 2021, a cluster sampling method was used to select 143 airline pilots in service as the research objects. The self-made emotion and stress source questionnaire, Chinese version of stress perception scale (CPSS) , self rating Anxiety Scale (SAS) and self rating Depression Scale (SDS) were used to investigate the airline pilot population. 136 valid questionnaires were collected, with an effective recovery rate of 95.1%. The measurement data conform to the normal distribution and are expressed by (x±s) . T-test and analysis of variance are used for comparison between groups, and Pearson correlation is used for correlation analysis. The data that do not conform to the normal distribution are expressed by the median and quartile [M (Q(1), Q(3)) ], and the non parametric test is used for the comparison between groups. Multiple linear stepwise regression was used to analyze the influencing factors of pressure perception. In addition, Amos 23.0 software was used to construct structural equation models of stress perception and negative emotions. Results: Under the background of the epidemic, the main sources of stress for civil aviation pilots are: the risk of possible reduction in income, the risk of contracting COVID-19, the pressure at work, and the risk of possible slow progress of upgrading. Among them, the first co pilot was more worried about the possible reduction of income than the instructor (P=0.009) ; The first co pilot and the captain of the airline were more worried about the possible slowdown of the upgrade progress than the instructor (P<0.001, P=0.014) . The mean pressure perception of pilots was higher than that of Chinese norm (t=3.11, P=0.002) . The standard scores of anxiety and depression were slightly higher than the standard scores of the Chinese norm under the non epidemic situation (t=7.00, 4.07, all P<0.001) . The results of multiple linear stepwise regression analysis showed that stress perception was negatively correlated with good family relations (t=-8.50, P=0.000) , and positively correlated with worries about slow progress of upgrading, COVID-19 infection, lack of interpersonal communication and income reduction (t=3.31、3.86、2.88、2.06, P<0.05) . Pressure perception was positively correlated with negative emotion (all P<0.001) . The results of structural equation model show that stress perception affects pilots' negative emotions directly or indirectly, and its standardized total effects on anxiety, depression, hypochondriac, fear, compulsion and irritability are 0.719, 0.811, 0.403, 0.355, 0.295 and 0.244 respectively. Conclusion: Public health emergencies have an impact on the mental status of pilots. Should pay attention to the stressors and psychological conditions of pilots in time, and consider formulating measures to relieve the stress of pilots.

Sleep Quality and Mental Health Consequences of COVID-19 Pandemic in the Aviation Community in Greece.

OBJECTIVE: The aim of this study was to assess the mental health and sleep quality of aviation workers in Greece during the pandemic. METHODS: A cross-sectional study of aviation workers in Greece was conducted. RESULTS: Sleep disturbances were observed in 25.4% of our 548 participants, whereas 8.2% and 5.8% reported at least mild depressive and anxiety symptoms, respectively. The impact of the pandemic on their mental health was their primary concern, which increased for many active pilots according to their workload. Those infected mainly faced daily tiredness and fatigue. Smoking habits and high body mass index were a predisposition for more physical symptoms. Cabin crew and women generally yielded worse scores than the other groups. CONCLUSION: Fear of infection could explain mental health issues, whereas physical symptoms of those infected could be attributed to long-COVID (coronavirus disease) syndrome. Flight attendants' lower ratings may be due to more occupational exposure.

A 5-Year Analysis of Aviation Medical Examinations in South Korea.

INTRODUCTION: Little has been studied to promote aviation health in South Korea. The aim of this study was to analyze the results of aviation medical examinations conducted in South Korea over the past 5 yr and, in doing so, provide evidence for establishing a health promotion, disease prevention plan.METHODS: Subjects of the study consisted of applicants who underwent aviation medical examinations from January 1, 2016, to December 31, 2020.RESULTS: Over the past 5 yr, the total number of aviation medical examinations in South Korea has shown an annual increase of more than 10%. In the presence of the COVID-19 pandemic in 2020, the number of aviation medical examinations, both renewal and initial, for all types of licenses, except renewal aviation medical examinations for the ATCL, decreased. Disqualification rates were generally higher in initial examinations than in renewal examinations. The examination results for license renewal showed the ATPL disqualification rate to be the highest at 3.5 per 1000 pilots per year in their 50s, with cardiology cases being the most common reason for disqualification, followed by ophthalmology cases and psychiatry cases. Diagnostic categories for those disqualified after initial aviation medical examinations were similar, though ophthalmological causes were most common, followed by cases of psychiatry and neurology.CONCLUSION: Main causes of disqualification in airmen and air traffic controllers were identified as the presence of cardiovascular, ophthalmic, and psychiatric diseases. The results of this study provide evidence for improving health promotion activity plans to manage risk factors of such diseases for aviation workers.Kim JS, Han BS, Kwon YH, Lim J. A 5-yr analysis of aviation medical examinations in South Korea. Aerosp Med Hum Perform. 2022; 93(6):499-506.

Cardiopulmonary assessment prior to returning to high-hazard occupations post-symptomatic COVID-19 infection: a position statement of the Aviation and Occupational Cardiology Task Force of the European Association of Preventive Cardiology.

This article provides an overview of the recommendations of the Aviation and Occupational Cardiology Task Force of the European Association of Preventive Cardiology on returning individuals to work in high-hazard occupations (such as flying, diving, and workplaces that are remote from healthcare facilities) following symptomatic Coronavirus Disease 2019 (COVID-19) infection. This process requires exclusion of significant underlying cardiopulmonary disease and this consensus statement (from experts across the field) outlines the appropriate screening and investigative processes that should be undertaken. The recommended response is based on simple screening in primary healthcare to determine those at risk, followed by first line investigations, including an exercise capacity assessment, to identify the small proportion of individuals who may have circulatory, pulmonary, or mixed disease. These individuals can then receive more advanced, targeted investigations. This statement provides a pragmatic, evidence-based approach for those (in all occupations) to assess employee health and capacity prior to a return to work following severe disease, or while continuing to experience significant post-COVID-19 symptoms (so-called 'long-COVID' or post-COVID-19 syndrome).

General Aviation Flight Safety During the COVID-19 Pandemic.

BACKGROUND/OBJECTIVE: The COVID-19 virus has caused over 582,000 deaths in the United States to date. However, the pandemic has also afflicted the mental health of the population at large in the domains of anxiety and sleep disruption, potentially interfering with cognitive function. From an aviation perspective, safely operating an aircraft requires an airmans cognitive engagement for: 1) situational awareness, 2) spatial orientation, and 3) avionics programming. Since impaired cognitive function could interfere with such tasks, the current study was undertaken to determine if flight safety for a cohort of single engine, piston-powered light airplanes was adversely affected during a period of the pandemic (MarchOctober 2020) prior to U.S. approval of the first COVID-19 vaccine. METHODS: Airplane accidents were per the National Transportation Safety Board Access ^{database. Fleet times were derived using Automatic Dependent Surveillance-Broadcast. Statistics used Poisson distributions, Chi-squared/Fisher, and Mann-Whitney tests. RESULTS: Little difference in accident rate was evident between the pandemic period (MarchOctober 2020) and the preceding (JanuaryFebruary) months (19 and 22 mishaps/100,000 h, respectively). Similarly, a proportional comparison of accidents occurring in 2020 with those for the corresponding months in 2019 failed to show over-representation of mishaps during the pandemic. Although a trend to a higher injury severity (43% vs. 34% serious/fatal injuries) was evident for pandemic-period mishaps, the proportional difference was not statistically significant when referencing the corresponding months in 2019. CONCLUSION: Surprisingly, using accidents as an outcome, the study herein shows little evidence of diminished flight safety for light aircraft operations during the COVID-19 pandemic. Boyd DD. General aviation flight safety during the COVID-19 pandemic. Aerosp Med Hum Perform. 2021; 92(10):773779.}

Exploring the effect of COVID-19 on airline environmental efficiency through an interval epsilon-based measure model.

COVID-19 has dealt an unprecedented blow to the aviation industry since 2020. This paper applies the interval epsilon-based measure (IEBM) model to evaluate the optimal quarterly environmental efficiency of 14 global airlines of passenger and cargo subsystems during 2018-2020. Then, the time series prediction method is applied to forecast the interval data of inputs and outputs from 2021 to 2022. Finally, we can calculate the quarterly efficiency. Thus, the future development trends of airlines can be predicted. The results show that (1) COVID-19 has hit the passenger subsystem harder, while the freight subsystem has become more efficient; (2) the efficiency of the freight subsystem has inevitably declined in the post-epidemic era; and (3) therefore, the airlines will have a "√" shaped recovery curve in the next few years.

Determinants of financial distress in the European air transport industry: The moderating effect of being a flag-carrier.

Due to the COVID-induced global collapse in demand for air travel, the year 2020 was a catastrophic one for the aviation industry. A dramatic drop in operating revenues along with continuing fixed expenses drained the cash reserves of airlines, with consequent risks of financial distress and, potentially, even of bankruptcy. Flag-carriers are a special group in the airline business-they are considered to have privileges in terms of the support given by governments while, on the other hand, are often viewed as having low efficiency and performance. This study aims to estimate for European airlines the interaction effect of being a flag-carrier (flagship) with the relationship between leverage, liquidity, profitability, and the degree of financial distress. Findings obtained from analysing 99 European airlines over a period of ten years, indicate that the negative influence of leverage on financial stability is higher in the case of flag carriers (flagship). The impact of liquidity and profitability on financial health is more positive for flagship than for non-flagship carriers. These findings are not limited to contributing to the existing literature, but also have significant practical implications for executives, managers, and policy makers in the European air transport sector.