Search Results (9)

With the rapid development of the low-altitude economy and smart logistics, unmanned aerial vehicles (UAVs), as core low-altitude platforms, have been widely applied in urban delivery, emergency rescue, and other fields. Although path planning in complex environments has become a research hotspot, optimization and scheduling of UAVs under time window constraints and task assignments remain insufficiently studied. To address this issue, this paper proposes an improved algorithmic framework based on a two-layer structure to enhance the intelligence and coordination efficiency of multi-UAV path planning. In the lower layer path planning stage, considering the limitations of the whale optimization algorithm (WOA), such as slow convergence, low precision, and susceptibility to local optima, this study integrates a backward learning mechanism, nonlinear convergence factor, random number generation strategy, and genetic algorithm principle to construct an improved IWOA. These enhancements significantly strengthen the global search capability and convergence performance of the algorithm. For upper layer task assignment, the improved ALNS (IALNS) addresses local optima issues in complex constraints. It integrates K-means clustering for initialization and a simulated annealing mechanism, improving scheduling rationality and solution efficiency. Through the coordination between the upper and lower layers, the overall solution flexibility is improved. Experimental results demonstrate that the proposed IALNS-IWOA two-layer method outperforms the conventional IALNS-WOA approach by 7.30% in solution quality and 7.36% in environmental adaptability, effectively improving the overall performance of UAV trajectory planning. Full article

To improve the quality of flight training in instrument failure scenarios, eye movement data were collected from flight instructors during climbing, descending, and turning flights when the primary attitude direction indicator failed. The performance data of the excellent instructors was selected to produce eye movement tutorials. These tutorials were used to conduct eye movement training for the experimental group of flight trainees. In contrast, the control group received traditional training. The performance and eye movement data of the two groups of flight trainees were then compared and analyzed. The results showed that flight trainees who received eye movement training performed better when facing instrument failure. Specifically, the deviations in the rate of descent, heading during the descent, airspeed during the turn, and slope during the turn were significantly different from those of the control group. Compared to the control group, the experimental group had a significantly lower fixation frequency on the failed instrument during the turn. Additionally, the average glance duration on the failed instrument during the climb and turn was significantly reduced. The study demonstrated the effectiveness of eye movement training in improving the quality of flight training in instrument failure scenarios. Full article

Electric aviation is the future development direction of aviation industry technology. Electric vertical take-off and landing aircraft(eVTOL) is an important carrier of electric aviation, whose technology research and development, processing and manufacturing, airworthiness certification and industrialization boom have been set off around the world. The electric propulsion technology has achieved rapid development as the key technology of eVTOL. Aiming at the demand for high torque density and high reliability of electric propulsion system, the paper analyzed the technical indexes of electric motor products of domestic and foreign benchmark enterprises. The key technologies such as motor integration, new electromagnetic topology, lightweight structure design, and high efficiency cooling is studied. It is pointed out that in order to pursue the high torque density and fault-tolerance performance, the integrated precise modeling of motor and controller, advanced materials and manufacturing technology are the development trend of the electric propulsion technology. The breakthrough of eVTOL electric propulsion technology can accelerate the commercial operation of civil eVTOL and promote the development of new quality productive forces. Full article

Due to the small size of the micro aircraft, it has high permeability and concealability, holding promise in application in the military and civil fields, and it has become a domestic and international research frontier and hotspot in the past decade. However, caused by the heavy onboard power supply and the decline in the actuator’s operating power at micro sizes, untethered flight is still a development difficulty at present. In this paper, we introduce a new micro vehicle configuration which is driven by onboard capacitive energy and can realise off-line free flight under the drive of electrostatic actuators. In the overall design, this paper proposes structural capacitors as the energy supply unit and buoyancy unit of the vehicle, which can overcome part of the vehicle body’s weight by being filled with helium gas, while the capacitor can provide electrical energy for the propulsion unit. The micro vehicle has a wingspan of 5 cm, a total mass of 165 mg, a stable operating voltage between 1300 V and 2400 V, and a flight time of more than 60 s under the condition of an onboard capacitor power supply. The micro vehicle designed in this thesis has a small wingspan, light weight, and better concealment, and it has broad application prospects in the future in environmental reconnaissance, surveying, and other scenarios. Full article

The full-scale aircraft fatigue test is a critical assessment and validation of the fatigue and damage tolerance design of new aircraft models, and it is also a prerequisite for obtaining the type certification for an aircraft. The full-scale fatigue test is an extremely complex and high-risk task that requires a lengthy period of time and significant financial investment. Therefore, there is an urgent need to shorten the test cycle and safely and efficiently complete the full-scale fatigue test during aircraft model development. Based on the experience and results of a nearly decade-long full-scale fatigue test conducted on a certain civil aircraft, and with reference to the full-scale fatigue test of the Boeing 777 in the United States, this article compares and contrasts the similarities and differences in aircraft configuration, test load spectrum, load application methods, and test detail control, as well as damage detection, monitoring, and maintenance. It analyzes the main reasons for the high time consumption and low efficiency of full-scale fatigue tests for domestic civil aircraft and proposes test acceleration schemes to further shorten the test cycle. The analysis results presented in this article provide valuable reference for the design of full-scale fatigue tests and relevant test personnel. Full article

Thailand’s civil aviation industry has expanded rapidly in the past ten years resulting in increasing aviation greenhouse gas (GHG) emissions and energy consumption. The rapid growth in air transport is anticipated to continue further. Presently, domestic aviation and the economy of many countries are recovering rapidly in the post-COVID-19 period, resulting in fuel consumption and GHG emissions gradually increasing again. However, despite implementing the ICAO’s CORSIA (International Civil Aviation Organization’s Carbon Offsetting and Reduction Scheme for International Aviation) rule for international aviation, GHG emissions in the domestic aviation sector are largely unregulated. Moreover, the literature lacks a GHG emissions analysis that considers this sector’s potential growth and mitigation policies for future GHG emissions. To close the gap, this study conducted a GHG emissions analysis from this sector under various scenarios through 2050 using historical data during 2008–2020 to forecast future trends. It evaluates the impact of the mitigation policies, such as fuel switching and aircraft technology, on improving fuel efficiency due to technological advancements in aircraft and carbon pricing. The results show that the fuel switching option would result in a significant long-term reduction in GHG emissions, whereas the carbon pricing option and aircraft technology option are desirable in reducing GHG emissions in the short term. Therefore, to meet GHG emissions reduction targets more successfully, all measures must be simultaneously executed to address short- and long-term mitigation strategies. These findings have significant implications for both present and future GHG emissions reduction measures, supporting Thailand’s 2050 climate targets and energy efficiency policies as the domestic aviation industry adjusts. Full article

Over the past 20 years, civil aviation has substantially reduced its environmental impact to augment sustainable transportation. In Spain, the domestic market has been habitually characterized by a few enterprises providing air transport services linked to scheduled flights on domestic corridors. Because of geographic diversity and the highly concentrated population characterizing this southern European country, many of them could not be supplied by alternative transport modes in terms of both time and distance by comparison with air transportation. For air quality monitoring from 139 national corridors, this paper aims to study related aviation emissions to conduct an economic analysis in terms of positive or negative externalities. For such purposes, the study focused on these domestic routes served by the five most important Spanish airports, specifically on the number of passengers transported from 2011 to 2020. Up to 10 aircraft types representing no more than 89% of regular operations on these flyways were subsequently identified. In addition, certain engine types also were selected as representatives to evaluate their emissions, depending on the great-circle distance in each route. The research findings, though particularly conditioned by aviation peculiarities of such a domestic market, point decisively to significant dependence upon emissions in connection with the seasonality of the demand and the concentration of flights with low occupancy indices from any one of them. Results suggest that airlines would benefit from operating turboprops instead of turbojets on selected routes, especially when oil prices are high. However, it is not always easy to find a balance between uncompromising economic profitability and effective fleet availability, since nowadays air transport undertakings tend to unify their fleets by using a few aircraft families, mostly powered by jet engines, apart from regional carriers. Full article

The International Civil Aviation Organization is estimated that the number of domestic and international passengers will be expected to reach six billion by 2030. This exponential growth in air transport has resulted in a wide range of adverse effects such as environmental impacts. The purpose of this research is to develop new air traffic management, and operator (pilots, air traffic controllers) load measuring systems in order to save fuel, and flight time, thereby reducing environmental impact, carbon emission, greenhouse gas generation, noise pollution, and operating cost. This paper deals with: (i) dynamic sectorization and airspace configuration (ii) introduction of the highly dynamic approach and landing procedures, (iii) dilemmas of human in sustainability (related to the individuals, the society, the non-governmental organizations, and the managers), and (iv) development of dedicated non-intrusive operator supporting systems based on eye-tracking, heart rate, and electrodermal activity. Due to the consequent effects of these developments, the dynamic sectorization and air space configuration may eliminate the task overload and reduce the actual operator load by 30–40%. With the developed concept of dynamic approach and landing procedures, aircraft will be able to follow better trajectories to avoid residential areas around airports to (i) reduce ground noise, and emission, (ii) avoid encounters severe weather and prevent incidents and accidents, and (iii) decrease landing distance up to 56% in compared to the “published transition route”. Full article

Stable and clear atmospheric conditions, lower surface temperatures, an ample moisture supply, and a strong low-level inversion persisting for most of the night usually facilitates the formation of dense fog during winter in Delhi. This severely hinders the flight operations at India’s busiest airport, the Indira Gandhi International (IGI) Airport, where more than 900 flight operations occur per day and an interruption can cause significant financial losses to the aviation industry. It is important to undertake a quantitative study of the estimated losses. This study, undertaken for the first time in India, aimed to evaluate the impact of dense fog at IGI Airport on economic losses which occurred during the winter season between 2011 and 2016. The breakdown of charges for different segments of flight operations for the domestic and international sectors was obtained from India’s Ministry of Civil Aviation and the Center for Asia Pacific Aviation (CAPA) India. A total of 653 h of dense fog between 2011 and 2016 at IGI Airport caused economic losses of approximately 3.9 million USD (248 million Indian rupees) to the airlines. The analysis further found that from 2014–2015 onwards, there has been a reduction in the number of flight delays, diversions, and cancellations by approximately 88%, 55%, and 36%, respectively, due to the strict implementation of guidelines to facilitate the Category (CAT)-III landing for aircraft during dense fog. Full article