Military Aviation Research Articles

Reliability of selected components of the PZL M28 Bryza aircraft

The increasing number of flight operations, and the resulting increased likelihood of adverse situations, intensifies the need for research into aspects of aircraft reliability. This article is devoted to the reliability of selected assemblies of the PZL M28 Bryza aircraft, widely used in military and civil aviation. The article presents the research object, the PZL M28 Bryza aircraft, and the research methodology to assess the reliability of its key assemblies. The research focuses on analyzing the failure rate of such assemblies as the propulsion system, airframe, radioelectronic devices and on-board systems, using in-service data. The results provide a better understanding of the critical aspects affecting the reliability of the PZL M28 Bryza aircraft, which is important for improving the safety and efficiency of flight operations conducted.

Phosphor Screens Color Preferences Depending on Night Vision Experience and Luminance Level.

One of the most important factors affecting visual performance during vision aided by night vision goggles (NVGs) is image quality, which depends mainly on the image-intensifier technology used. Although NVGs with green image color (P43 phosphor) are only accepted in military aviation, white image (P45 phosphor) seems to be equally well-regarded by aviators. The aim of our study was to determine if the experience of using NVGs with the green screen affects image preference for that color, and if the screen color preference is related to luminance level. Subjects (127 military pilots, 26-56 yr, M = 37.2; 62 pilots with flight experience with NVG use) were asked to observe a model terrain board at two different luminance levels (corresponding roughly to ambient conditions during starlight and one-half moonlight) while using two types of NVGs (green P43 and white P45 phosphor screens). The pilots were asked to answer a questionnaire about their preference for NVG display color. The findings showed a significant difference between screen color preference and pilots' experience with the green-phosphor-based NVGs (43.5% vs. 23.1% for white screens). However, there was no relationship between screen color preference and luminance level. Previous NVG experience seems to play an important role in shaping a user's individual preference for a certain phosphor screen color, although green and white phosphor screens both provide satisfactory visibility. Nevertheless, when deciding, it is advisable to experiment with both colors and select the one that suits the user's preferences and needs. Lewkowicz R, Dereń-Szumełda J. Phosphor screens color preferences depending on night vision experience and luminance level. Aerosp Med Hum Perform. 2024; 95(10):749-757.

Specific Technologies of Aviation Rescue and Firefighting Operations over the Years

The twentieth century was a period of rapid development in aviation. It was a time of great progress in the construction of aircraft, the development of ground infrastructure and the improvement of qualifications of aviation personnel. Over the years, aviation has gone from cruise flights in simple aircraft to transatlantic flights, complex aircraft with hundreds of passengers on board. Military aviation can operate at speeds exceeding the speed of sound and in all weather conditions. The infrastructure of large airports has reached the size of cities. Over the past century, the development of aviation has been followed by changes in the organization and equipment of rescue and fire-fighting services. The public does not accept the loss of human life or large-scale material damage and environmental damage. In the search for effective extinguishing agents and methods of administering them, people began to look for ways other than field fire services. Specialized firefighting units have appeared at airports, which are designed for specific rescue and firefighting operations on aircraft and infrastructure. For many years, attempts have been made to select special rescue and firefighting technologies capable of improving the effectiveness and safety of operations. Quite quickly, the car was chosen as the means of transport for airport rescue services. But over time, the need was recognized for it to have different characteristics and equipment than a vehicle for village and town safety units. As a result of various experiments, unusual technical solutions designed to solve basic problems specific to airports were developed. Equally interesting was the path to determining the best fire extinguishing agents and their means of administration. From hand-held fire extinguishers to remote-controlled cannons administering thousands of liters or kilograms of extinguishing agents over a long distance. The publication provides information on the history and development of basic firefighting technologies specific to aviation and some pointers to the future.

An introduction to the current state of standardization and certification on military AI applications

The main objective of this article is to provide an overview of the current state of development regarding certification and standardization efforts for Artificial Intelligence (AI) systems in military aviation. The incorporation of AI capabilities in the military holds the potential for significant strategic advantages in information and decision supremacy. However, AI also brings novel risks and safety considerations that existing certification processes are inadequate to address. Consequently, the need arises for the establishment of an entirely new certification framework, encompassing requirements and standardized processes tailored to the unique demands of AI safe-ty. During the development of such framework, the 7 High Level Requirements of the EU AI High Level Experts Group are taken as reference to develop the successive horizontal (cross-domain) and vertical (domain-specific) standards that would produce legal, robust and ethical AI. To facilitate the creation of a new AI certification framework in military aviation, a review has been done over traditional civil and military certification processes and the current AI certification progress under development, to present an overview of the key elements and processes involved. References from various levels (regulatory, industry, research) have been considered to provide an introduction to the prospective military AI certification framework.

THE DOCTRINE OF AIR WARFARE BY GIULIO DOUHET IN THE SOVIET MILITARY-SCIENTIFIC JOURNALISM AND FICTION OF THE 1920S-30S

The article says about reflection of the doctrine of air warfare of Italian military theorist Giulio Douhet (1869-1930) in military, scientific, popular science and artistic literature in the USSR in 1920-30s, its criticism by Soviet specialists, discussions about the role of aviation in the wars-to-be. According to the said concept, the lack of military aircrafts, primarily bombers, might cost an entire war. Numerous Soviet leaders in the 1920s saw aviation as a formidable military force and as a kind of ‟locomotive” capable of driving industry, science and culture. It is logical that Giulio Douhet’s doctrine aroused their great interest. The works of the Italian general and some works of other foreign authors related to his doctrine, were repeatedly published in the USSR. Prominent military commanders and aviation specialists took part in their publication and discussion. Those disputes were intertwined with discussions about the role of aviation in the wars-to-be. Some authors believed that there was a rational grain in the doctrine of Giulio Douhet, and aviation could put enemy on the brink of defeat in short time. Others insisted on the need to prepare for a protracted war, where aviation would play an important role, but only as one of the means of struggle. As a result, the 1920s-30s’ discussion of Giulio Douhet’s theory in the USSR reflected significant aspects in the development of views on the tasks of the air fleet.

Burden and Risk Factors of Cervical Spine Conditions in Military Aircrew From 1997 to 2015: A Retrospective Cohort Study.

Military aviators may have increased risk of cervical spine injuries because of exposure to supraphysiologic forces and vibration during dynamic flight. Aviator medical attrition impairs mission readiness, decreases operational capabilities, increases overall DoDcosts, and decreases retention of seasoned aviators. This study evaluated incidence and risk factors for cervical spine conditions in U.S. military aviators from 1997 to 2015. The Defense Medical Epidemiological Database was queried for aviators with a diagnosis of cervical spine conditions. Pertinent ICD-9 codes for cervical spine pathology were ascertained from U.S. Army, Air Force, and Naval Air Forces aeromedical references. Negative binomial regressions assessed sex, age, service, aircraft, and year on incidence of conditions. Rates were compared to non-aviator controls. The study was approved by the Institutional Review Board at the Naval Health Research Center (NHRC.2020.0205-NHSR). Incidence rates were 9.78 to 12.57/1,000 person-years for neck pain, 2.04 to 3.89/1,000 person-years for degenerative conditions without neurological involvement, and 0.94 to 1.36/1,000 person-years for degenerative conditions with neurological involvement. Aviation occupation (relative risk [RR] 1.41-2.05), female sex (RR 3.32-7.89), age over 40 (RR 2.39-4.62), and service in the Army or Marine Corps (RR 1.62-2.14) were risk factors. Military aviators had a statistically significant increase in risk of neck pain and medically disqualifying degenerative cervical spine conditions compared to non-aviator controls. Rates of neck pain increased in all aviators over the study epoch. Possible explanations could be related to the operational demands and the increased use of forward helmet-mounted display systems during the study period, a supposition that requires further investigation. There was no significant difference in rates of neck pain or degenerative cervical conditions between aircraft platforms (fighter/bomber, other fixed wing, and rotary wing). Female sex, age over 40 years, and Army/Marine Corps service were the greatest risk factors for neck pain and degenerative cervical spine conditions. Targeted prevention programs and expanded treatment modalities are necessary to reduce aviator attrition and Department of Defense cost burden.

Maternal and Fetal Health Risks Among Female Military Aviation Officers.

INTRODUCTION: Military aviation poses unique occupational risks, including exposures to intermittent hypoxia, high gravitational force, and toxic materials, in addition to circadian disruption, cosmic radiation, and ergonomic stressors also present in commercial flight. We sought to investigate whether a military aviation officer's career is associated with adverse maternal or fetal health outcomes.METHODS: We conducted a retrospective cohort study of female aviation and nonaviation officers in the Military Health System from October 2002 to December 2019. Exposure was identified as assignment of an aviation occupation code. Maternal and fetal health outcomes were identified by International Classification of Diseases codes from medical records. Regression analysis was used to estimate adjusted relative risks (aRR).RESULTS: Included in the study were 25,929 active-duty female officers, with 46,323 recorded pregnancies and 32,853 recorded deliveries; 2131 pregnancies were diagnosed in aviation officers. Pregnant aviation officers had a decreased risk of composite adverse pregnancy outcomes [aRR 0.82 (0.73-0.92)], including gestational diabetes [aRR 0.69 (0.57-0.85)] and gestational hypertension [aRR 0.84 (0.71-0.99)]. Pregnant aviation officers had a decreased risk of depression prior to delivery [aRR 0.43 (0.35-0.53)] and hyperemesis gravidarum [aRR 0.74 (0.57-0.96)], but an increased risk of placental complications [aRR 1.15 (1.02-1.30)] and fetal growth restriction [aRR 1.36 (1.16-1.60)].DISCUSSION: Pregnant military aviation officers have an increased risk of placental complications and fetal growth restriction in spite of a lower risk of gestational diabetes and gestational hypertension. Further research is needed to determine how flight-related occupations impact pregnancy.Stark CM, Sorensen IS, Royall M, Dorr M, Brown J, Dobson N, Salzman S, Susi A, Hisle-Gorman E, Huggins BH, Nylund CM. Maternal and fetal health risks among female military aviation officers. Aerosp Med Hum Perform. 2024; 95(9):675-682.

The U.S. Army Aeromedical Research Laboratory Virtual Reality Vection System.

Vection is a stationary individual's illusory experience of self-motion. This illusory self-motion is operationally important for aviation, particularly military aviation, since vection is a dramatic example of spatial disorientation (SD), which is an individual's failure to correctly sense the aircraft's position, motion, and/or attitude with respect to the fixed coordinate system of the Earth's surface and its gravitational vertical. Notably, SD is a major cause of fatal aviation mishaps, and the visual system is particularly prone to provoking vection. This article describes the Virtual Reality Vection System (VRVS), which uses computer-controlled virtual reality technology to induce vection under controlled conditions for training, demonstration, testing, and research. The VRVS enables the precise specification of the number and appearance of visual stimulus elements intended to generate vection, including photorealistic images. The VRVS can present visual stimuli on any OpenXR-capable virtual reality headset. The VRVS currently records 2 types of behavioral responses, button presses to indicate the presence and duration of vection and the voltage of a handheld linear potentiometer to indicate the presence, duration, and magnitude of vection. An approved test plan helped guide, organize, document, and validate the VRVS during its development. Under this plan, a pair of tests guided hardware and software development of the VRVS system. Although the first test verified the ability of the VRVS to generate and measure vection, it also demonstrated that the VRVS can quickly manipulate the visual stimuli from one trial to the next so that the VRVS can support complex experimental designs. The second test used these capabilities to verify that the VRVS can characterize vection in a more analytic fashion using a masking paradigm. Specifically, the test assessed whether random stimulus elements injected into the vection-inducing stimulus disrupted vection in a quantifiable fashion. This work opens the door to studies that characterize the necessary and sufficient visual elements for vection-based SD. The VRVS is currently used to research, develop, test, and evaluate mitigation strategies targeting vection-related SD in degraded visual environments. Similarly, the VRVS is supporting research to develop methods to predict individual differences in visually induced motion sickness susceptibilities. The VRVS is currently being integrated with a precision motor-controlled rotating Barany chair for multisensory studies. It should be noted that since the VRVS was developed to support United States Army Aeromedical Research Laboratory projects, it is an Army product representing government intellectual property and may be freely available to other government institutions.

Development of Interactive Framework for Aviation Part Task Trainer (APTT) for Supersonic Fighter Aircraft

In commercial, military and general aviation, safe and effective training is the important requirement, which is achieved through an Aircraft Part Task Training device (APTT). When compared with the live training, the most significant benefits of ground training is improved safety and the reduced cost of a pilot training process. Flight simulation is a multidisciplinary subject that relies on several research disciplines which have a tendency to be investigated separately and in parallel with each other. This manuscript presents a comprehensive overview of the research work done within the APTT. The development of interactive framework for Aviation part task trainer is discussed in detail. The interactive graphics display is interfaced with different pilot controls such as throttle, pedal and control stick . The acquired data is processed and displayed on multifunctional display, giving the feel of flying in the aircraft. Thus the pilot can be trained on ground reducing the risk. Graphic symbols are prepared using OpenGL software. LAN connection is established using socket program in C and MATLAB aerospace toolbox is used for taking the input through joystick.

Arterial Oxygen Desaturation Hinders Gamified Working Memory Performance.

Hypoxia presents a physiological challenge to the Warfighters during military aviation and subterranean warfare operations by decreasing the supply of oxygen to the brain, which results in a reduced cognitive function depending on the magnitude and duration of hypoxic exposure. Moderate hypoxic exposures, fractions of inspired oxygen (FiO2) of 0.11 to 0.14, show no effects on simple tasks, but complex tasks like working memory may be hindered. Unfortunately, people often cannot recognize their own symptoms of hypoxemia, which are individualistic at moderate hypoxic exposure. Thus, screening tools, like gamified cognitive assessments, during moderate hypoxia may provide personnel objective feedback to initiate safety protocols before a possible accident. However, whether gamified assessments of working memory are sensitive to moderate hypoxia is unknown. Therefore, we tested the hypothesis which moderate normobaric hypoxia decreases gamified working memory performance when accounting for the individualistic responses of arterial blood oxygen saturations. Following 3 consecutive days of 2 practice sessions per day, 30 healthy adults (25 ± 5 years, 10 women) completed three 1-min rounds of the tablet-based working memory game (Backtracker, Statespace Labs, Inc.) at baseline and 60 and 90 min after exposure to FiO2 (= 0.138 ± 0.002 [hypoxia] and 0.201± 0.004 [normoxia] oxygen). Both conditions were completed on the same day and administered in a single-blind, block randomized manner. Arterial oxyhemoglobin saturation was estimated via forehead pulse oximetry (SpO2). Data were analyzed using linear mixed effects modeling. Compared to normoxia (99 ± 1%), SpO2 was lower (P < .001) at 60 (90 ± 2%) and 90 (90 ± 2%) min of hypoxia. A decrease in SpO2 was associated with a statistically significant decrease in the proportion of both tiles with the correct location (P < .02; -0.016) and correct order of appearance recalled (P < .01; -0.016). A decrease in SpO2 was associated with a statistically significant decrease in median time to first tap (P < .01; -0.041s) and median time between taps (P<.01; -0.030s). A significant interaction effect between the SpO2 decrease and baseline performance was found for proportion of tiles with the correct location recalled (P < .05; -0.014), median time to first tap (P <.01; -0.070s), and median time between taps (P < .01; -0.037s). A significant interaction effect between the SpO2 decrease and the path length was found for the proportion of tiles with the correct location recalled (P < .01; +0.021), median time to first tap (P < .01; -0.036s), and median time between taps (P < .01; -0.043s). These findings indicate that greater decreases in SpO2 during moderate hypoxic exposure hinder performance on a gamified assessment of working memory as measured by the proportion of correctly identified order and location of tiles. Considering the statistically significant decrease in both median time to first tap and median time between taps associated with the decrease in SpO2, participants are taking less time to plan or execute movements, which may compound or independently contribute to spatial and temporal memory mistakes.

Incorporating military certification practices in the aerospace industry for enhanced safety and compliance

This study investigates the transfer of certification practices from the military aviation industry to the aerospace sector, emphasizing operational safety and compliance with international standards. The objective is to analyze and compare military certification processes with those of innovative aeronautical and space products, aiming to enhance their effectiveness and applicability. The adopted methodology includes a systematic literature review on military and aerospace certification, as well as a detailed comparison of the type certification processes for aeronautical and space designs. The main results highlight the shared technological complexity and economic challenges faced by the sectors, underscoring the critical need for comprehensive certification processes to ensure safety and regulatory compliance, supporting strategic objectives in advancing a safe aerospace sector aligned with global standards.

Over a decade of UAV incidents: A human factors analysis of causal factors

This analysis examined systemic causes of Uncrewed Air Vehicle (UAV) accidents identifying operator, environmental, supervisory, and organisational factors through the use of the Human Factors Analysis and Classification System (HFACS). HFACS is a system-based analysis method for investigating the causal factors associated with accidents and incidents and has previously been used to reliably and systematically identify active and latent failures associated with both military and general aviation accidents. Whilst HFACS has previously been applied to UAV accidents, the last known application was conducted in 2014. Using reports retrieved from nine accident investigation organisations’ databases, causal factors were coded against unsafe acts, preconditions, and failures at the supervisory, organisational, and environmental levels. Causal factors were assessed on 77 medium or large UAV mishaps/accidents that occurred over a 12-year period up to 2024. 42 mishap reports were deemed to involve a human factor as a causal factor. A large proportion of the mishaps contained factors attributed to Decision Errors at level 1 (Unsafe Acts) which was found to be associated with both the Technological Environment and Adverse Mental State at level 2 (Pre-conditions). Causal factors were identified at each of the other 3 levels (Supervisory, Organisational and External) with a number of emergent associations between causal factors. These data provide support for the identification and development of interventions aimed at improving the safety of organisations and advice of regulators for Uncrewed Air Systems.

Determining infrared radiation intensity characteristics for the exhaust manifold of gas turbine engine ТВ3-117 in МІ-8МSB-B helicopter

The object of this study is the screen-exhaust device in the TV3-117 engine of the Mi-8MSB-B helicopter. To reduce visibility in the thermal range, a system of mixing hot engine exhaust gases with ambient air is used; this technique makes it possible to reduce the infrared radiation of engines. For this purpose, a new sample of screen-exhaust device was designed for testing. A thermal imaging survey of the helicopter was conducted. Three variants of thermal images were acquired: a helicopter without installation of a thermal visibility reduction system, a helicopter with standard exhaust shields installed, and a helicopter with newly developed shield exhaust devices installed. Based on the obtained experimental results, the characteristics of the intensity of infrared radiation were determined for three variants of research in the range of thermal waves of 3–5 μm. The study uses a comprehensive approach to solving the tasks, which includes a statistical analysis of known and promising ways to protect a helicopter from guided missiles with infrared homing heads based on reduced radiation forces and a theoretical method for calculating flow and temperature fields. The advantages of placing the section of the exhaust channel of the designed screen-exhaust device in the horizontal plane for complete shielding of infrared radiation in the lower hemisphere have been experimentally proven. The benefits of directing the flow of exhaust gases from the screen-exhaust device into the space above the helicopter propeller and dividing this flow into four separate flows were shown. The results of experimental research could be used to design new or improve existing screen-exhaust devices by the developers of military aviation

Cyber Resiliency of Aircraft Systems: A Literature Review

Aircraft have an important role in the overall defense of almost every country. However, military aircraft are not only susceptible to traditional kinetic weapons but also to constantly developing cyber weaponry. There has been global growth in the number of cyber threats in recent years, and the field of military aviation is not outside the growing threat. The war in Ukraine and recent military aircraft procurements in Europe make the topic very timely. A highly skilled and resourced adversary is able to conduct complex long-term attacks that penetrate even well-protected systems, such as military aircraft systems. Even air-gap does not protect aircraft from cyber threats as modern aircraft have complex and networked avionics and support systems. The study aims to find the current trends of cyber security research related to aircraft systems. The included topics are, for example, cyber resiliency and cyber protection in the system life cycle. The study concentrates particularly on forming an overall view of the most vulnerable military aircraft systems. The study presents a non-systematic literature review based on public data sources, such as research reports, articles, etc. A set of nine relevant sources was chosen for detailed qualitative analysis. Because of the lack of detailed military sources, applicable study materials related to commercial passenger aircraft were included. The results suggest that the most vulnerable aircraft systems from the viewpoint of cyber security are those that are exposed to threats via communication and satellite systems. Other vulnerable systems are sensors and avionics systems that transfer, or process critical data related to the functions of the aircraft. In addition, the study found that it is difficult to protect aircraft systems from cyber threats because of their complexity, maintenance operations, and supply chains, which also increase the size of the attack vector. To tackle the issue, it is important to follow the development of regulations and policies related to cyber security in aviation and to study the methods of managing the threat in a holistic and cost-effective manner.

Modafinil Subjectively Does Not Impair Sleep in Aviators After a Period of Extended Wakefulness.

INTRODUCTION: Modafinil is used as a countermeasure to limit the effects of fatigue in military aviation. However, literature is conflicting about its negative effects on subsequent sleep.METHODS: This randomized placebo-controlled trial conducted by the Center of Man in Aviation of the Royal Netherlands Airforce is part of a larger study. It included 32 subjects (mean age 35 yr old, 84% male) who followed a normal daily routine and stayed awake the subsequent night. At midnight, all subjects received either 300 mg caffeine, 200 mg modafinil, or placebo. At the end of the test night, subjects were awake for a median period of 26 h. Afterwards, sleep questionnaires containing qualitative (Groningen Sleep Quality Scale) and quantitative parameters of sleep for the subsequent day (recovery sleep) and consecutive night (post-test sleep) were completed and statistically analyzed using Friedman and Wilcoxon signed rank tests.RESULTS: A statistically significant difference in the reported recovery sleep was observed. The modafinil group slept 30% shorter than placebo, but sleep efficiency was not statistically different. Quantitatively post-test sleep did not vary statistically significantly between the three groups. However, Groningen Sleep Quality Scale scores were lower post-test than pre-test in the modafinil group, while this was not the case in the caffeine and placebo group.DISCUSSION:This study found that modafinil subjectively does not negatively impact recovery sleep or subsequent nighttime sleep after an extended period of wakefulness and suggests it may decrease the need for recovery sleep compared to placebo or caffeine.Wingelaar-Jagt YQ, Wingelaar TT, Riedel WJ, Ramaekers JG. Modafinil subjectively does not impair sleep in aviators after a period of extended wakefulness. Aerosp Med Hum Perform. 2024; 95(6):290-296.

Sustainable Airport Management and Airline Marketing

The aviation sector comprises every industry that provides direct assistance to mechanical air transportation. The aviation industry includes a variety of institutions, such as military aviation companies, aircraft manufacturers, and various commercial establishments, all of which play important roles. The analysis of airline market shares was carried out within the realm of the aviation industry. Considering the ongoing trajectory of increasing airline market shares, it is crucial for firms to commit resources towards investing in this industry. Furthermore, a thorough evaluation of the existing literature revealed a dearth of research specifically focused on airline marketing. The primary objective of this research was to address the existing gap in the literature. Sustainable airport management and business, the airline industry, business-to-business analytics in the airline sector, customer satisfaction, and customer experience were some of the facets investigated in this study. In addition, the study seeks to provide a SWOT analysis of the airline marketing strategies employed by transportation corporations.

Experimental investigation of the effect of air/fuel ratio change on JP8 swirl flame characteristics with image processing methods

In this study, the stable combustion ranges and emission values of JP8 fuel, which is used in military aviation, were tested and optimum conditions were determined. The AFR (Air/Fuel Ratio) of the JP8 flame was increased experimentally at constant thermal power in a gas turbine combustion chamber. In the study, AFR were tested as 30/1, 33/1, 36/1, 39/1 and 42/1. A generator with 0.4 swirl number is placed at the burner outlet. Under these conditions, the effect of external acoustic enforcement frequencies on dynamic instabilities at different AFR was investigated. Flame length and thickness data were extracted from the images obtained from the image processing technique. The effect of AFR change on the combustion chamber temperature was examined and pollutant emissions were measured. The results showed that the most stable flame appeared in AFR 33/1 case at 155 and 300 Hz resonance frequencies under acoustic enforcements. Additionally, when the AFR was increased to 42/1, flame instability increased at all frequency values. Moreover, it has been determined that the most optimum mixture in terms of combustion chamber exit temperature and CO emissions is AFR 33/1. There was an increase in NOX emissions by up to 39/1 with the increase in AFR.

Population health implications of exposure to pervasive military aircraft noise pollution.

While the adverse health effects of civil aircraft noise are relatively well studied, impacts associated with more intense and intermittent noise from military aviation have been rarely assessed. In recent years, increased training at Naval Air Station Whidbey Island, USA has raised concerns regarding the public health and well-being implications of noise from military aviation. This study assessed the public health risks of military aircraft noise by developing a systematic workflow that uses acoustic and aircraft operations data to map noise exposure and predict health outcomes at the population scale. Acoustic data encompassing seven years of monitoring efforts were integrated with flight operations data for 2020-2021 and a Department of Defense noise simulation model to characterize the noise regime. The model produced contours for day-night, nighttime, and 24-h average levels, which were validated by field monitoring and mapped to yield the estimated noise burden. Established thresholds and exposure-response relationships were used to predict the population subject to potential noise-related health effects, including annoyance, sleep disturbance, hearing impairment, and delays in childhood learning. Over 74,000 people within the area of aircraft noise exposure were at risk of adverse health effects. Of those exposed, substantial numbers were estimated to be highly annoyed and highly sleep disturbed, and several schools were exposed to levels that place them at risk of delay in childhood learning. Noise in some areas exceeded thresholds established by federal regulations for public health, residential land use and noise mitigation action, as well as the ranges of established exposure-response relationships. This study quantified the extensive spatial scale and population health burden of noise from military aviation.We employed a novel GIS-based workflow for relating mapped distributions of aircraft noise exposure to a suite of public health outcomes by integrating acoustic monitoring and simulation data with a dasymetric population density map. This approach enables the evaluation of population health impacts due to past, current, and future proposed military operations. Moreover, itcanbemodified for application to other environmental noise sources and offers an improved open-sourcetool to assess the population health implications of environmental noise exposure, inform at-risk communities, and guide efforts in noise mitigation and policy governing noise legislation, urban planning, and land use.

Preliminary Envelope for Large Transport Aircrafts Operating with Non-Primary Fuels AVGAS, MOGAS and F76-Dieso

This study explores the operational implications and safety considerations of using non-primary fuels—AVGAS, MOGAS, and F76 Dieso—in military transport aircraft, against the backdrop of standard aviation fuels. Through an analysis of fuel properties such as vapor pressure, density, viscosity, freeze temperature, water solubility, and thermal conductivity, this work outlines the operational envelopes for the mentioned non-primary fuels, highlighting the temperature and altitude limitations inherent to their use. The evaluation underscores the necessity of relevant testing, certification, and adherence to operational guidelines and constrains to ensure aircraft safety and reliability when standard fuels are unavailable, and hence, non-primary fuels may be required in special missions under emergency. Key findings include the specific altitude and temperature limitations for AVGAS and MOGAS to prevent fuel freezing and boiling, as well as the operational challenges posed by F76 Dieso due to its higher density and viscosity. The study also addresses the importance of managing water content in the fuel system, the flammability range of the non-primary fuels, and the considerations for fuel mixing to maintain aircraft performance and safety standards. This analysis aims to enhance the understanding of non-primary fuel usage in military transport aircraft, providing insights for system design, performance assessment, and the development of operational procedures to support military aviation in diverse operational scenarios.

ОСОБЕННОСТИ ФУНКЦИОНИРОВАНИЯ СЛЕНГИЗМОВ В СФЕРЕ ВОЕННОЙ АВИАЦИИ

The article is devoted to the sociolinguistic study of slang in the field of military aviation. The relevance of the study is determined by the interest in issues related to the theoretical study of slangisms and their use in the language of military aviation. The purpose of the study is to study the distinctive features of slangisms in the field of military aviation in the lexical and semantic aspect.The research material was slangisms denoting the names of various aircraft, words and expressions that are used to designate certain objects, concepts or actions. As a result of the study: it has been proven that slang is a complex linguistic formation that reflects in the language the linguistic, sociological and cultural characteristics of an individual, manifested in the verbalization of his speech. A thematic classification of slang expressions is presented, based on their lexical and semantic analysis, conclusions are drawn about the peculiarities of the mentality of military aviation specialists.