Increase In Flight Time Research Articles

Examining flight time, cognitive reflection, workload, stress and metacognition on decision making performance for pilots during flight simulation

Despite technological advancements, human decision errors still contribute to civil aviation accidents. This study investigated whether flight time, cognitive reflection, task-load, metacognition, and perceived stress predicted decision-making (DM) performance during two in-flight training simulations with 104 commercial pilots at Bogota International Airport. Hierarchical regression analysis revealed that the predictors accounted for 56% of the variance. Cognitive reflection, flight time and performance task load emerged as significant positive predictors. Cognitive reflection significantly moderated the relationship between flight time and DM performance, with pilots scoring lower on cognitive reflection showing improved DM with increased flight time, while controlling for performance task load. The study did not find significant relationships between stress metacognition and DM performance. The study emphasises the significance of advanced training methods in improving pilots’ DM, especially for those with low cognitive reflection. Future research should expand to multiple airlines, address gender balance, and incorporate direct measures of metacognitive monitoring.

Parametric Optimization of Structural Frame Design for High Payload Hexacopter

For drones, the use of which has been increasing recently for load carrying, lightweight drone frame design is significant for increased flight time and payload capacity. Drones are produced in different configurations with three, four or six rotors, and in different sizes depending on the purpose of use. While agility is more important in three and four rotor drone applications, six-rotor and relatively large-bodied drones are preferred in cases such as load carrying. When the body structure has to be large, lightening the design becomes very critical. Lightweight designs can be achieved by two commonly used methods for structural optimization: topology optimization and parametric optimization. Topology optimization is an advanced method that can significantly reduce weight but is expensive and time-consuming. Parametric optimization is a more practical approach for conventional manufacturing methods and was used in this study. This study aims to first simplifying the hexacopter frame model and defining key geometric parameters for mass-decreasing optimization. Finite element analysis simulations were used to evaluate the strength and deformation of the frame under various design scenarios. The results showed that parametric optimization successfully reduced the weight of the hexacopter frame while maintaining structural integrity. The maximum Von Mises stress was found as approximately one quarter of the yield strength of the frame material. The maximum total deformation was achieved below 0.3 mm, and deformation under 1 mm is considered safe in the literature. As a result, the optimized design offers a lighter drone structure in line with conventional manufacturing methods, providing better flight time and payload capacity while maintaining cost effectiveness. In future studies, comparisons can be made based on this study by performing weight optimizations suitable for current methods such as topology optimization or generative design. the cost factor and the availability of existing production lines should be taken into consideration when comparing the mentioned methods with parametric optimization.

Investigation of calendaring parameters on the microstructure of graphite anodes within lithium-ion batteries: Insights from ultrasonic testing

The study explores the application of ultrasonic testing to analyse the impact of the calendaring process on the microstructure of graphite anodes within a lithium-ion battery. It examines the correlation between calendaring parameters such as roll gap and line speed, and their impacts on ultrasonic signal characteristics.Our study reveals that different sample thicknesses responded differently to the calendaring process. Specifically, the amplitude of the first peak increased for thinner samples (<45 μm) post-calendaring, indicating improved material uniformity, whereas thicker samples (>50 μm) demonstrated increase in Time of Flight with reduced attenuation in acoustic signal. Notably, thinner electrodes (45 μm) exhibit a substantial density increase from 0.95 to 1.6 gr/cm³, surpassing the density gain in thicker electrodes (100 μm) which rise from 1.0 to 1.3 gr/cm³ under identical calendaring conditions.This initial study confirms that a clear correlation exists between the properties of the acoustic waveform and variations in the calendaring process parameters. These results will form the basis of a future study investigating the possible in-line sensing, process control and quality assessment of electrode manufacture. The data obtained from this study's characterisation process has the potential to underpin a data-driven model to predict calendaring performance using machine-learning methods.

How athletes’ biomechanical running characteristics effect running economy during the use of running shoes with and without carbon inserts

To maximise running economy (RE), shoe manufacturers placed carbon plates within the midsole of shoes. Shoe technology research is limited on understanding the variability of individual responses to carbon-plated shoes and how these responses vary across running velocities. Little research on same shoe characteristics with and without a stiff element has been completed. This study aimed to investigate how running shoes with carbon versus without a carbon composite stiff element alter individual running biomechanics and the metabolic cost of running. Ethical approval was gained from Cardiff Metropolitan University Ethics Committee. Ten male athletes (69 ± 9 kg; 174 ± 4 cm; 28 ± 9 years) completed two submaximal incremental treadmill runs. One test was completed in a shoe without carbon (C1), the other test was completed in carbon shoes (C2), the order of testing for each shoe were randomised. Running velocity started at 9 km/h and increased by 1 km/h every four mins, blood lactate samples were taken after every stage. Once 4 mmol·L−1 (OBLA; the second lactate turn point) had been reached one more stage was completed. Gas exchange was analysed throughout the whole test. The first 15 s of the final 2 minutes of each stage was recorded using Theia3D markerless motion capture software (Theia3Dv2022.1.0.2309, Theia Markerless, Inc., Kingston, ON, Canada). Data were analysed in 4 stages, the initial stage, pre-OBLA, OBLA and post-OBLA. Physiology data were averaged over the final two mins of each stage. Discrete joint angles were taken from each stage, and an average of the 15 s recording was taken for spatiotemporal measure. Data were analysed using a four-way repeat measures ANOVA, to show individual differences. Non-parametric data were analysed using Wilcoxon signed-rank test. Hedges g calculations were completed to calculate effect size (ES). Results showed significant increase in flight time (FT; P = 0.04, ES = 0.20) in the pre-OBLA stage when using C2. Metatarsophalangeal joint (MTP) dorsiflexion showed significant increase during the initial stage in C2 (P = 0.05, ES = 0.8), and ankle dorsiflexion had significant increase in the post-OBLA stage in C2 (P = 0.03, ES = 0.2). The were no significant differences present in the physiology data. Across the physiological, spatiotemporal and kinematics, high dispersions around the mean were exhibited. Findings suggest that to improve RE, mechanical and spatiotemporal changes need to be present when using C2. Further findings show carbon shoes elicit highly individual responses to both RE and mechanics of running.

Time characteristics of aero-optical imaging degeneration of the ellipsoidal dome under variable operating conditions

As a missile flies at high speed, the index and surface shape of the conformal dome will vary under the influence of the aero-optical effect, which will degenerate the performance of the seeker’s imaging detection system. However, many previous studies on aero-optical imaging deterioration of optical domes were usually carried out under fixed operating conditions, which are not in line with the real flight scene of the missile. In addition, the aero-optical imaging degeneration of the dome is diverse as the flight time increases. Therefore, it is of great significance to study the time characteristics of aero-optical imaging degradation of optical domes under variable work conditions. In this study, taking an air-to-air missile as an example, the Zernike polynomials, wavefront aberration, Strehl ratio, and image simulation are applied to evaluate the aero-optical imaging deterioration of an ellipsoidal dome in the flight time range of 0–10 s under variable working conditions. The simulation results show that, as the flight time increases, (1) the dynamic range of tilt, defocus, astigmatism, coma, and wavefront aberration increase; and (2) the Strehl ratio and the peak signal-to-noise ratio (PSNR) of the simulated images decrease. Therefore, the influence of flight time on the aero-optical image degradation of the ellipsoidal dome gradually becomes more serious.

RTMS Ameliorates time-varying depression and social behaviors in stimulated space complex environment associated with VEGF signaling

Studies have indicated that medium- to long-duration spaceflight may adversely affect astronauts' emotional and social functioning. Emotion modulation can significantly impact astronauts' well-being, performance, mission safety and success. However, with the increase in flight time, the potential alterations in emotional and social performance during spaceflight and their underlying mechanisms remain to be investigated, and targeted therapeutic and preventive interventions have yet to be identified. We evaluated the changes of emotional and social functions in mice with the extension of the time in simulated space complex environment (SSCE), and simultaneously monitored changes in brain tissue of vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), and inflammation-related factors. Furthermore, we assessed the regulatory role of repetitive transcranial magnetic stimulation (rTMS) in mood and socialization with the extension of the time in SSCE, as well as examining alterations of VEGF signaling in the medial prefrontal cortex (mPFC). Our findings revealed that mice exposed to SSCE for 7 days exhibited depressive-like behaviors, with these changes persisting throughout SSCE period. In addition, 14 days of rTMS treatment significantly ameliorated SSCE-induced emotional and social dysfunction, potentially through modulation of the level of VEGF signaling in mPFC. These results indicates that emotional and social disorders increase with the extension of SSCE time, and rTMS can improve the performance, which may be related to VEGF signaling. This study offers insights into potential pattern of change over time for mental health issues in astronauts. Further analysis revealed that rTMS modulates emotional and social dysfunction during SSCE exposure, with its mechanism potentially being associated with VEGF signaling.

체조 뜀틀 다리 벌려 넘기 동작의 성공적인 수행을 위한 운동학적 비교분석

Objectives This study was conducted for the purpose of improving gymnastic function by dividing the movement into 4 phases and 3 sections targeting 2 groups of 5 people for the purpose of successful performance during the gymnastic jumping frame jump movement. Methods In the experiments of this study, time factors, hand positions, stride length, and angle variables were compared by group through a motion analysis program. Results Frst, the time required to perform the movement was long in the successful group due to the upward movement of the center of the body and the upward change in flight time required to stably cross the jumping frame. Second, the vertical height of the center of the body was higher in the successful group in the phase of placing hands on the jumping frame (E3), resulting in an increase in flight time. showed low results. Third, in order to raise the upper body and successfully cross the vault, the head, elbow, and body angles were greatly extended in the successful group. In order to increase the ground reaction force and improve the vertical speed in the suc-cessful group, the knee angle showed a larger flexion result. Fourth, the successful group showed a relatively large step length corresponding to the horizontal distance in the direction of movement. This is considered to be a factor necessary for performing a motion in which no part of the body touches the jumping frame. Conclusions For a successful vaulting jump, you must stare straight ahead, stamp your feet, and reach your hands farther away to touch the front of the back of the hoop. While pushing your hands on the jumping frame, raise your upper body, and at this time, make your hips and upper body connected to the body horizontal. You have to jump over the hoop with your knees extended and your legs spread, and you must perform a successful motion that reduces the amount of impact by slightly bending your knees as you land.

Analysing the Impact of Go-Around Occurrences at Large European Airports

Go-arounds (GoA) or missed approaches are standard flight procedures initiated when an approach is aborted for safety reasons, requiring pilots to reposition the aircraft for a subsequent landing attempt. This study leverages ADS-B data sourced from the OpenSky Network, collected at 20 major European airports between January 2019 and July 2023. Out of 6.7 million retrieved landing trajectories, 20,196 GoA were identified and analyzed. We conducted statistical evaluations on these GoA instances to compare the rates of GoA at different airports, market segments, and aircraft types. We also looked at the distributions of distance, duration, and fuel consumption of GoA for the different airports. Of particular note, we quantified the impact of a GoA on the surrounding arrival traffic by analyzing how GoA events affect Arrival Sequencing and Metering Area (ASMA) timings. Our results show that the rate of GoA at the assessed airports ranged from 1.5 to 6 occurrences per 1,000 landings. The median duration and distance of a GoA varied depending on the airport, falling between 11.5 and 16.5 minutes, and 36.5 and 58.2 NM respectively. During a GoA, an Airbus A320 typically consumes between 350 and 600 kg of fuel. Importantly, our findings demonstrate that a GoA occurrence can significantly impact the efficiency of arriving traffic at an airport, causing disruptions lasting up to an hour. ASMA timings tend to increase directly after a GoA occurs and peak for landings occurring 10 to 25 minutes after a GoA, with flight time increases ranging from 30 to 100 seconds, depending on the airport. These timings gradually return to their pre-GoA levels within the following hour, though certain airports may experience longer recovery periods. This comprehensive study on GoA provides a deeper understanding of their impact, offering valuable insights that can support data-driven decision-making in the aviation industry.

러시아-우크라이나 전쟁과 국제관광

Since the World Health Organization(WHO) declared a pandemic due to the COVID-19 outbreak on March 11, 2020, the international tourism industry has suffered an unprecedented blow. In the international tourism market, which was in a gradual recovery of period, Russia's invasion of Ukraine on February 24, 2022, subsequent Western sanctions, and a counterattack by Russia, were enough to cause a new level of uncertainty. After the Russia's invasion of Ukraine, Ukraine and Moldova closed their airspace, and Western countries imposed measures such as a ban on takeing off and landing and flying in their own airspaces, and the suspension of the code-sharing agreement on planes belonging to Russian airlines. Russia also responded and it has become inevitable for neighboring countries to change air routes. This led to an increase in flight time and an increase in air ticket costs, which negatively affected international tourism. Nevertheless, international air ticketing declined for the two weeks after the outbreak of the war, but demand for international tourism has gradually recovered since then. According to the UN World Tourism Organization's Tourism Recovery Tracker data, the number of international tourist arrivals around the world at the end of 2022 recovered to 65% compared to 2019 before the pandemic, exceeding the expected recovery of 37% to 50% compared to 2019, an estimated scenario announced by the UN World Tourism Organization in January 2022. In particular, the number of international tourist arrivals in Europe has recovered to 80% compared to 2019, indicating a fairly rapid recovery compared to 27% in the Asia-Pacific region. In addition, the number of international tourist arrivals around the world from January to March 2023 recovered to 80% compared to 2019 before the pandemic, 90% in Europe, and 72% in Central and Eastern Europe. And it can be seen that the recovery is faster not only than experts expected at the beginning of the outbreak of war, but also than the result of the survey on the recovery period of international tourism to the pre-pandemic level, which was surveyed by experts from each country by the UN World Tourism Organization before the outbreak. And the number of Russians entering Korea in 2022, 60,019, which is 17.5% compared to 343,057 in 2019 before the pandemic, and the number of Russian patients using medical institutions in Korea was 9,616 in 2022, which is 32.2% compared to 29,897 in 2019. Although the pace of recovery is not faster than that of other countries, considering that the number of arrivals from January to May 2023 was 60,671, which has already exceeded the annual number of arrivals in 2022, the impact of the Russian-Ukrainian war on the Korean inbound tourism market can be seen as insignificant.

Comparative Analysis of Cosmic Radiation Exposure Dose Due to the Russian Detour Route

Since the World Health Organization (WHO) officially announced a global pandemic on March 12, 2020, the aviation industry in the world has been experiencing difficulties for a long time. Meanwhile, the Ukraine war broke out in February, and from March 15, domestic airlines must operate air routes bypassing Russian airspace despite the longer flight time. Therefore, as the flight time increases, the cosmic radiation exposure dose of the crew members is also expected to increase. Here we compare the radiation exposure dose between the route doses for the eastern United States and Europe before and after the detour route usage. Through the comparison analysis, we tried to understand how cosmic radiation changes depending on the flight time and the latitude and which one contributes more. We expect that this study can be used for the policy update for the safety management of cosmic radiation for aircrews in Korea.

A Survey on Energy Optimization Techniques in UAV-Based Cellular Networks: From Conventional to Machine Learning Approaches

Wireless communication networks have been witnessing unprecedented demand due to the increasing number of connected devices and emerging bandwidth-hungry applications. Although there are many competent technologies for capacity enhancement purposes, such as millimeter wave communications and network densification, there is still room and need for further capacity enhancement in wireless communication networks, especially for the cases of unusual people gatherings, such as sport competitions, musical concerts, etc. Unmanned aerial vehicles (UAVs) have been identified as one of the promising options to enhance capacity due to their easy implementation, pop-up fashion operation, and cost-effective nature. The main idea is to deploy base stations on UAVs and operate them as flying base stations, thereby bringing additional capacity where it is needed. However, UAVs mostly have limited energy storage, hence, their energy consumption must be optimized to increase flight time. In this survey, we investigate different energy optimization techniques with a top-level classification in terms of the optimization algorithm employed—conventional and machine learning (ML). Such classification helps understand the state-of-the-art and the current trend in terms of methodology. In this regard, various optimization techniques are identified from the related literature, and they are presented under the above-mentioned classes of employed optimization methods. In addition, for the purpose of completeness, we include a brief tutorial on the optimization methods and power supply and charging mechanisms of UAVs. Moreover, novel concepts, such as reflective intelligent surfaces and landing spot optimization, are also covered to capture the latest trends in the literature.

Flight Time Optimization and Modeling of a Hybrid Gasoline–Electric Multirotor Drone: An Experimental Study

Drones have evolved rapidly over the decades, but the limited flight time inhibits multirotor drones from performing long-duration tasks. Batteries that power drones are considered an inadequate power source due to their low energy density. As gasoline is an energy-dense source, combining an electric propulsion system with gasoline engines should be considered. This paper proposes a novel hybrid multirotor drone design using two gasoline engines to provide the majority of the lift force and four electric motors to stabilize the drone. These propulsion systems have been characterized and optimized to exploit their respective advantages, which reduce the total energy consumption rate and increase flight time. Simulation and experimental results show that the hybrid gas–electric multirotor drone can achieve more than three times the flight time of the fully electric drone.

Peering through the thicket: Effects of UAV LiDAR scanner settings and flight planning on canopy volume discovery

Unoccupied aerial vehicle laser scanning (UAV-LS) has been increasingly used for forest structure assessment in recent years due to the potential to directly estimate individual tree attributes and availability of commercial solutions. However, standardised procedures for campaign planning are still largely missing. This study investigated scanner properties and flight planning to provide recommendations on minimising forest canopy occlusion and thereby maximise exploration of canopy volume. A flight campaign involving two UAV-LS systems was conducted over a dense, wet tropical forest at the Paracou research station (French Guiana). Four experiments on scanner properties and flight planning were conducted, analysed and recommendations derived. First, the scanner pulse repetition rate (PRR) should be at least 100 kHz per 1 m s −1 flight speed based on 360° FOV for exploration of middle canopy strata (5 m to 20 m). Higher PRR are beneficial for exploration of lower canopy ( < 5 m) but would need to be increased exponentially to achieve linear improvement. Alternatively, flight speed could be reduced within the constraints given by the inertial measurement unit (IMU), but would increase flight time. Second, the scanner maximum range was identified as a proxy for the laser pulse power, which positively impacts canopy exploration. This was particularly the case when using multi-return capabilities. No saturation could be observed when increasing the laser power, suggesting that this is currently a limiting factor. Additionally, a smaller laser beam divergence and pulse width were plausible reasons for better exploration of the upper canopy just below the top of canopy. Third, off-nadir scanning angles up to 20° were found to result in similar occlusions, suggesting a practical FOV of 40° in the investigated dense forest. This number might be larger for open canopies. UAV-LS systems with viewing geometries that focus laser pulses downwards and within optimal ranges should be preferred. Fourth, using different horizontal flight directions in the mission planning favours minimisation of occlusion. A minimum of two different flight directions is suggested. However, specific optimal yaw angles were not possible to predict before flight. Therefore, including multiple directions ensures coverage of all possible configurations. Many of these investigated features can be optimised independently from each other, and should be considered before acquisition of new UAV-LS systems and flight mission planning. These results support the establishment of general guidelines for the investment in UAV-LS systems and optimal mission planning for forest structure assessment. • Introduction of absolute, geometrical and turbid occlusion concepts. • Longer range scanners explore more canopy volume facilitated by multiple returns. • Scanner wavelength possibly affects detection of woody elements vs foliage. • Scan angles ±20°off-nadir exhibited lowest occlusion effects. • Combining multiple flight directions supports canopy discovery.

Maximum aerobic speed, maximum oxygen consumption, and running spatiotemporal parameters during an incremental test among middle- and long-distance runners and endurance non-running athletes.

BackgroundMaximal aerobic speed (MAS) is a useful parameter to assess aerobic capacity and estimate training intensity in middle- and long-distance runners. However, whether middle- and long-distance runners reach different levels of MAS compared to other endurance athletes with similar V̇O2max has not been previously studied. Therefore, we aimed to compare V̇O2max, MAS and spatiotemporal parameters between sub-elite middle- and long-distance runners (n = 6) and endurance non-runners (n = 6). In addition, we aimed to compare the maximal blood lactate concentration [BLa] experienced by participants after conducting these tests.MethodsTelemetric portable respiratory gas analysis, contact and flight time, and stride length and rate were measured using a 5-m contact platform during an incremental test at a synthetic athletics track. V̇O2, heart rate, respiratory quotient values in any 15 s average period during the test were measured. [BLa] was analyzed after the test . Running spatiotemporal parameters were recorded at the last two steps of each 400 m lap. A coefficient of variation (%CV) was calculated for each spatiotemporal variable in each participant from 8 km h−1 onwards.ResultsWhereas runners reported faster MAS (21.0 vs. 18.2 km h−1) than non-runners (p = 0.0001, ES = 3.0), no differences were found for V̇O2max and maximum blood lactate concentration during the running tests (p > 0.05). While significant increases in flight time and stride length and frequency (p < 0.001, 0.52 ≤ n}{}{eta }_{p}^{2} ≤ 0.8) were observed throughout the tests, decreases in contact time (p < 0.001, n}{}{eta }_{p}^{2}=0.9) were reported. Runners displayed a greater %CV (p = 0.015) in stride length than non-runners. We conclude that middle- and long-distance runners can achieve a faster MAS compared to non-running endurance athletes despite exhibiting a similar V̇O2max. This superior performance may be associated to a greater mechanical efficiency. Overall, runners displayed a greater ability to modify stride length to achieve fast speeds, which may be related to a more mechanically efficient pattern of spatiotemporal parameters than non-runners.

Racewalking on a treadmill alters gait characteristics without increasing risk of disqualification

ABSTRACT Purpose Treadmill training is useful for racewalking training; however, it may affect gait characteristics and lead to non-legal techniques. The aim of this study was to determine the kinematic differences between treadmill and overground conditions during racewalking at different speeds. Methods Twenty-two elite racewalkers participated in this study. They racewalked under treadmill and overground conditions at high and medium speeds. A 12-camera motion analysis system was used to record the racewalking trials. Results Significant condition by speed interactions were detected in step frequency and pelvis rotation angle; step frequency decreased while pelvis rotation angle increased from overground to treadmill conditions at high speed. Compared to overground conditions, racewalkers decreased the ankle dorsiflexion angle at heel strike and increased hip flexion, shoulder hyperextension, and elbow flexion angles at heel strike and hip and shoulder extension angles at toe-off under treadmill conditions. Compared to medium speed, racewalkers decreased the contact time, hip flexion, and shoulder hyperextension at heel strike, and ankle plantarflexion and shoulder extension angles at toe-off, and increased flight time, step length, and elbow flexion angle at heel strike at high speed. Conclusion Several kinematic differences during racewalking were detected between treadmill and overground conditions, with more differences detected at high speed, indicating that treadmill racewalking, especially at high speed, has different gait characteristics. However, no differences were detected in flight time and knee angle under treadmill conditions compared to overground conditions, indicating that racewalking on a treadmill does not increase the risk of disqualification.

Improving UAV Mission Quality and Safety through Topographic Awareness

The field of Unmanned Aerial Vehicles (UAVs) has progressed greatly in the last years. UAVs are now used for many applications and are often flown automatically. One commonly implemented feature in an automatic flight is that of following a mission at a stable altitude. However, this altitude is almost always referenced from the take-off location and does not take terrain profile levels into account. This is a critical and dangerous issue because if the terrain level changes abruptly (e.g., mountain regions or buildings in a city), this can lead to crashes or an unintended (illegal) high altitude. Our aim for this work is to provide a solution such that a constant altitude above ground level is maintained. To this end, we make use of the readily available Digital Elevation Models (DEMs). These models, which contain the terrain elevation, help us in dynamically adjusting the VTOL UAV altitude so that it remains nearly constant in relation to the ground. Results have shown that with the use of our method, the altitude can be maintained sufficiently constant while introducing a limited increase in flight time and battery consumption that is proportional to the terrain’s irregularity. In a moderately changing terrain, the error could be reduced to just ±5 m.

Influence of airspace avoidance due to political and safety issues on flight efficiency and environment

In the history of aviation there were many cases that led to the obligation or necessity to bypass certain airspaces, mainly due to political and safety reasons. One of the latest events is the incident over Belarusian airspace. The fundamental concept of the article is to examine the effects of the necessity to avoid certain airspaces by the operators, using the incident over Belarusian airspace as an example. Based on the observations of air traffic flow over affected region, route distance extension was calculated using the Horizontal Flight Efficiency method. Subsequent calculations include potential increase in flight time, fuel consumption, carbon dioxide emission and operating costs. The results were extrapolated to yearly amounts. based on the air traffic prediction reports. The air traffic prediction analysis as well as the results of the calculations and simulations indicate that the bypass of the airspaces on flight routes important to global economy, has a serious impact on the environment and operators’ budget due to increased aircraft’s fuel consumption resulting in growth of carbon dioxide emissions as well as operating costs. It also leads to deterioration in the European Airspace’s capacity, causing the necessity for Air Traffic Management units to reorganize the air traffic flow over the affected regions. Potential solutions mitigating the problem were also proposed.

Design, analysis and prototyping of a spherical drone for underground mines

This paper aims to provide performance optimisation of a multirotor drone that is designed for underground spaces. Currently, drones are being used efficiently for various applications in surface fieldwork projects. But using drones for underground spaces is challenging because of confined space, GPS-denied environment and various air properties in underground spaces. In this paper, first, the designed and manufactured drone is discussed. Then, to improve the drone performance for defined missions, a sensitivity analysis is done over the effective design parameters of the drone components and air density as an environmentally effective parameter. The sensitivity analysis over the flight simulations shows that drone performance increases by increasing air density, while the optimised number of propellers blades is presented. The results show that by increasing the battery capacity, the flight time increases but the overall performance of the drone decrease. Also, the drone would be able to carry about 450 grams payload and payloads more than 450 grams can significantly decrease flight time. Finally, the results of sensitivity analysis lead to optimise the drone performance efficiently for the designed mission in underground mines.

Assessment of the Method of Merging Landing Aircraft Streams in the Context of Fuel Consumption in the Airspace

The most important directions in the field of sustainable development of air transport concern increasing the capacity of airports and improving the global civil aviation system, improving air traffic safety, and developing procedures to optimize the operation of the aviation system. An important area is environmental protection and measures to minimize the negative impact of civil aviation activities on the environment. Air traffic and the operation of airports generate adverse environmental effects, including greenhouse gas emissions, air pollution, and noise emissions. Due to the high intensity of aircraft maneuvers, the authors analyzed aircraft traffic in the area approaching the airport. It is essential to correctly line up for aircraft reporting from different entry points to the approach area to avoid waiting for landing. Misalignment of landing aircraft negatively impacts airport capacity, increases fuel consumption through more prolonged waiting times in space, and directly impacts air pollution. There are different ways to organize landing aircraft flows and other ways to merge these flows. The article aims to assess the method of combining the streams of landing aircraft and estimate the impact of such an organization on the increased fuel consumption of aircraft and thus on air pollution. The authors proposed a measure for assessing the quality of the landing queue, which was defined as the increase in flight time of aircraft in the approach area in relation to the nominal time, which was adopted as minimization. In order to obtain the results of research works, a model using a Petri net was developed, allowing for flexible mapping of concurrent processes and their effect analysis. Various methods of combining the streams of landing aircraft have been adopted: three-stage, two-stage, and single-stage. Then, simulation experiments were carried out, allowing the determination of whether the method of combining the streams of landing planes has an impact on the quality of the landing queue measured with the proposed index. The obtained results of the assessment can be used to estimate the increased fuel consumption of the aircraft.

In Situ MIMO-WPT Recharging of UAVs Using Intelligent Flying Energy Sources

Unmanned Aerial Vehicles (UAVs), used in civilian applications such as emergency medical deliveries, precision agriculture, wireless communication provisioning, etc., face the challenge of limited flight time due to their reliance on the on-board battery. Therefore, developing efficient mechanisms for in situ power transfer to recharge UAV batteries holds potential to extend their mission time. In this paper, we study the use of the far-field wireless power transfer (WPT) technique from specialized, transmitter UAVs (tUAVs) carrying Multiple Input Multiple Output (MIMO) antennas for transferring wireless power to receiver UAVs (rUAVs) in a mission. The tUAVs can fly and adjust their distance to the rUAVs to maximize energy transfer gain. The use of MIMO antennas further boosts the energy reception by narrowing the energy beam toward the rUAVs. The complexity of their dynamic operating environment increases with the growing number of tUAVs and rUAVs with varying levels of energy consumption and residual power. We propose an intelligent trajectory selection algorithm for the tUAVs based on a deep reinforcement learning model called Proximal Policy Optimization (PPO) to optimize the energy transfer gain. The simulation results demonstrate that the PPO-based system achieves about a tenfold increase in flight time for a set of realistic transmit power, distance, sub-band number and antenna numbers. Further, PPO outperforms the benchmark movement strategies of “Traveling Salesman Problem” and “Low Battery First” when used by the tUAVs.