ABSTRACT The research relevance is predefined by the air travel number growth. Accordingly, the relevance of this issue is increasing, especially concerning air travel safety. Also, due to the increasing demand for international flights, it becomes essential to harmonize the standards and methodology of training aviation personnel. The research aims to consider the parameters of flight safety and the impact of the unification of training programs for aviation personnel. The conclusion that unification can significantly affect safety was made with the help of scientific and special methods, including analysis, synthesis, concretization, and generalization. An analysis of existing unification methods was conducted. The multi-crew pilot training program proved to be one of the most advanced compared to standard flight crew training programs. The method was determined to be a specialized training program tailored to the needs of the aviation industry and focused on training pilots for multi-crew and jet operations. The program is more challenging, intensive and dynamic, and includes a significant amount of simulator training. Traditional flight training programs, such as Private Pilot Licenses (PPL), Commercial Pilot Licenses (CPL), instrument qualification, and multi-engine rating, have a broader scope and provide pilots with more career opportunities. Simulator training has been identified as a critical component of many flight training programs and plays a vital role in flight safety. The study may be of interest to a range of readers concerned with the issue of standardizing aviation training and improving safety in aviation, including researchers, faculty, and students of higher education institutions in the aviation field.

ABSTRACT Couple stresses because of magnetic particles additives on the lubrication performance of a journal bearing system was embraced and scrutinized in the current examinations theoretically. The governing equations of Reynolds (pressure field), energy (temperature field), and heat conduction (temperature field through the solids) are coupled and solved instantaneously in term of temperature and viscosity. After these set of equation pressure is obtained, it is used to obtain the bearing characteristic. It was found that the load currying capacity and maximum pressure are increased due the employing of magnetic fluids along with the couple stresses, as well as side leakage flow and the friction coefficient are decreased. It can be also concluded that the magnetic fluids with couple stresses are better lubricant than magnetic fluid only (l = 0), Newtonian fluids, and couple stress fluid (ʎ = 0).

ABSTRACT This work presents the design and prototyping of two 1U standard CubeSats for the First Brazilian MCTI Satellite Olympiad, launching one in a stratospheric helium-filled balloon. The nanosatellites were designed for two missions: Internet of Things connectivity in remote areas based on CubeSat (IoSat) and low-orbit harmful gamma radiation mapping (LOHGRM). The IoSat mission aimed to provide server connectivity for a remote sensor network. The LOHGRM CubeSat was designed for sensing and mapping gamma radiation power levels in the satellite’s orbit to construct a heat map to study the gamma radiation effect on the equipment. The prototype’s performance was evaluated based on physical, mechanical, magnetic, thermal, and transmission characterization, with satisfactory results under test conditions. The LOHGRM mission test was carried out on the ground as proof of concept without flying while a stratospheric balloon launched the IoSat prototype. Due to restrictions imposed by the competition, the IoSat nanosatellite only captured and registered altitude, pressure, and temperature data without testing the communication payload. Instead, this data was sent to the ground station through the competition communication system and stored in a memory card to assess its operation during the flying. The satellite’s maximum altitude was 22.6 km, operating under –23.5 °C.

ABSTRACT Cusped-field Hall thrusters (CFHT) have significant potential for use in many space missions due to their simplicity, long life and high efficiency. CFHT-27, designed and developed at the Bogazici University Space Technologies Laboratory (BUSTLab), is a prototype CFHT with a 27-mm diameter discharge channel. CFHT-27 utilizes samarium-cobalt (SmCo) permanent magnets. The thrust and efficiency of a cusped-field thruster is closely related to its size and design parameters. In this study, in order to understand the relationships between the design parameters and the thruster performance, the performance tests of the CFHT-27 are carried out for a given magnetic field topology. The thruster was operated at discharge voltages ranging from 250 to 500V with argon propellant with up to 3,000 s of specific impulse. The measurements show that CFHT-27 can achieve thrust values from 1 to 46 mN. Thus, this thruster can be used for a wide range of thrust values allowing throttle capabilities for different missions.

ABSTRACT Fixed-wing unmanned aerial vehicles (UAVs) offer the best aerodynamic efficiency required for long-distance or high-endurance applications, albeit their runway requirement for take-off and landing in comparison with quadcopters, helicopters, and flapping-wing UAVs that can perform vertical take-off and landing (VTOL). Integrating a multirotor system with a fixed-wing UAV imparts VTOL capabilities without significantly compromising fixed-wing aerodynamic efficiency, endurance, payload capacity or range. Documented system design approaches to address various challenges of such fusion processes are sparse. This research proposes a holistic approach for designing, prototyping, and testing an electric-powered fixed-wing hybrid VTOL UAV. The proposed system design approach augments the standard aircraft design process with additional steps to integrate VTOL capabilities. Separate fixed-wing and multirotor designs were derived from the frozen mission requirements, which were then fused. The process used simulation for modeling and evaluating alternatives for the hybrid UAV created using standard aircraft design equations. We prototyped and instrumented the final design to validate operational capabilities through test flights. Multiple flight trials identified the ideal combination of Lithium-Polymer (Li-Po) batteries for VTOL (8000mAh) and fixed-wing (14000mAh) modes to meet the endurance and range requirements. The redundant power supplies also increased the survivability chances of the hybrid UAV during failures.

ABSTRACT Solar energy is one of the most efficient forms of renewable energy. Solar air collectors are promising utilization of solar energy. The present study used unsteady three-dimensional Computational Fluid Dynamic (CFD) analysis to investigate the heat transfer and fluid friction in solar air collectors with smooth and v-corrugation absorber plates. The studied parameters are Reynolds number, v-corrugation height, and pitch. Three Reynolds number (500, 1000, 1500) values were used with three arrangements configuration of the v-corrugation of relative heights of 0.10, 0.16, and 0.23. Roughness pitches varied between 1.33, 1.66, and 2. By comparing the simulated thermal efficiency with the currently known experimental values, great agreement can be approved. Results show the superiority of the performance of v-corrugated collector against the traditional or smooth type. The outlet temperature obtained in case of relative roughness height = 0.23 and relative roughness pitch = 2 is 61 °C, while it is 53 °C for a smooth type. Also, a higher thermal efficiency of 46.7 % can be obtained compared to 33.01% for smooth type.

ABSTRACT Currently, the presence of spurious microwave radiation is increasing in the environment, which has caused concern due to possible health problems in living beings and electromagnetic interference in electronic systems. To control this problem, studies in the materials area are taking place, aiming to attenuate the spurious radiation and meet requirements of good performance in broadband, low cost and low weight. The present work aimed to study Cu and Ni nanometric films with thicknesses of 65 and 200 nm, deposited on polyethylene terephthalate substrate by magnetron sputtering. Scanning electron microscopy with a field emission gun (FEG-SEM) showed that the films produced have different morphological textures, due to the parameters used in the sputtering process and also the free energy of metals. Impedance spectroscopy measurements showed that the films have low conductivity values, due to the metallic oxides formed on the film surfaces, confirmed by X-ray diffraction, and also to the presence of defects. Electromagnetic characterization (8.2 – 12.4 GHz) showed that the Cu and Ni thin films had low performance, except the Ni_200 nm film, which showed a total shielding efficiency of about 30% in broadband. This result is promising considering the nanometric thickness of the Ni film.

ABSTRACT The use of smart devices is driving the growth of modern systems markets, resulting in more technological cities, cars, houses, and airplanes. Therefore, it is important to understand which smart technologies can support or even fulfill stakeholder needs and consequently enhance airplane operation and increase product competitiveness for airlines. This paper is the second of two-part series and has as its main objective the study of smart technologies that can be implemented on cabins of regional airplanes, from 60 to 120 seats, to comply with the needs and requirements pre-established on the first part of this series of articles. The integration of those technologies results in a “Smart Cabin” architecture which its purpose is to enhances the passenger experience by granting a new level of cabin comfort, customization, and connectivity that allows the reduction of airplane time on ground because of the real-time monitoring of airplane cabin components that enables the prediction of maintenance procedures; creates new profits and revenues opportunities for services, provides a more sustainable airplane operation and derived services, and creates new business opportunities for all companies that integrate regional aviation ecosystem.

ABSTRACT New technologies are increasingly being implemented in people’s daily lives and with the growth of smart devices around the globe, the users’ needs and demands have changed in favor of more technological cities, cars, houses, and airplanes. Therefore, it is important to define the stakeholder’s needs and requirements to understand which technologies, smart or not, can be implemented on the cabin to support or even fulfill stakeholder needs. Consequently, those technologies enhance airplane operation and increase product competitiveness for airlines. This paper is the first of a two-part series where design thinking tools are applied to establish high-level requirements based on the concept of a “Smart Cabin” for regional airplanes from 60 to 120 seats. To achieve this goal, a series of methods such as stakeholders’ studies, personas creation and user journey methods are used. The Smart Cabin concept aims to enhance the passenger experience by granting a new level of cabin comfort, customization and connectivity that allows the reduction of airplane time on ground because of the real-time monitoring of airplane cabin components that enables the prediction of maintenance procedures, creates new profits and revenues opportunities for services, provides a more sustainable airplane operation and derived services, and creates new business opportunities for all companies that integrate regional aviation ecosystem.

ABSTRACT The use of continuous fibers reinforced polymeric composites has increased substantially in the last year’s due to their high specific mechanical strength compared to other materials. Despite this property, this class of material is susceptible to low, medium, or high energy impacts, which can cause severe damage to composite laminates. One of the most serious damages is delamination, which can lead to partial or total rupture of the structure. In order to minimize this problem, several studies have been carried out in this area. In this context, this work aims to evaluate the influence of aramid reinforcement with bi-directional (2D) and tri-directional (3D) arrangements impregnated with two epoxy resins of different stiffness on the impact strength of composites submitted to the 340 J dart drop test. The impact results showed that the 2D composites had lower impact strength than the 3D ones, with the presence of perforations (when impregnated with the more rigid resin) and delaminations. Delaminations occurred regardless of the epoxy resin used in the impregnation. On the other hand, the 3D composites impregnated with the less rigid epoxy matrix absorbed more energy (3DF: 97.9%) with less deformation and no delamination compared to the 2D laminate (2DF: 96.1%) produced.

ABSTRACT In order to intercept hypersonic vehicles in near-space, a head-pursuit cooperative guidance law is proposed in this paper. Firstly, interceptors are regarded as multi-agents, and the communication relationship between them is represented by graph theory. Based on the time consistency theory of multi-agent system and sliding mode theory, a guidance law is designed along line-of-sight (LOS) to ensure the time cooperation of interceptors. Secondly, considering the requirement of the head-pursuit theory to the lead angle, a finite-time guidance law is designed perpendicular to LOS to ensure that each interceptor can complete head-pursuit interception. For the purpose of improving the intercept precision, extended state observers are used to estimate the system disturbances. The correctness of the guidance law is analyzed by Lyapunov stability theory. Finally, numerical simulations are presented and the results further verify the correctness of the guidance law. nearspace, nearspace near space, space near-space headpursuit head pursuit paper Firstly multiagents, multiagents multi agents, agents multi-agents multiagent agent lineofsight line sight (LOS Secondly angle finitetime finite interception precision disturbances Finally

ABSTRACT Airports are seen as a crucial component of infrastructure in the construction of modern cities in the Middle East, where aviation is recognized as a top priority in their development strategy. While the airline industry in the Middle has been investigated, there are no studies that explored the region’s successful global aviation hubs from a national competitive advantage perspective. Therefore, this paper examines the macro environmental elements affecting a nation’s competitiveness in the aviation industry using a mixed-methods approach, including Porter’s notion of national competitive advantage and expert views. The analysis shows that while macro environmental factors such as geographical advantage, physical and intellectual infrastructure, and business attractiveness are important for a successful aviation development, they are not necessarily required to guarantee a hub status unless the governments are devoted to developing the sector. East strategy investigated regions region s perspective Therefore nations nation mixedmethods mixed methods approach Porters Porter views sector

ABSTRACT Several aspects make nitrocellulose based powders adequate as a solid propellant for rockets and missiles and the prefe rable propellant to be used in firearms and artillery: it produces less smoke and less fouling than other propellants; its burning rate shows a well-defined relation to pressure and the composition of the gaseous mixture resulting from its decomposition by burning can be predicted with relatively high levels of accuracy. This last feature, if coupled with adequate thermodynamic models, leads to a reliable framework for the simulation of internal ballistics and, ultimately, to an efficient design. Some simpler models use an ideal gas approach, which is obviously not adequate, and some others perform corrections based on the Virial E quation of S tate for sake of algebraic simplicity. This work employs the Peng-Robinson equation of state to model the pressure-volume-temperature (PVT) behavior of the gases produced during the burning reaction, once it is known to be accurate in the high pressures obtained inside combustion chambers. The results were compared to experimental data obtained in a closed vessel device and showed that the Peng-Robinson equation of state could predict the chamber pressure with higher accuracy. artillery propellants welldefined well defined accuracy feature ultimately design approach simplicity PengRobinson Peng Robinson pressurevolumetemperature volume temperature PVT (PVT reaction chambers

ABSTRACT Vacuum chambers providing a low pressure environment similar to the vacuum environment in low earth orbit have been used for the testing of plasma thrusters. A significant proportion of research on the effects of vacuum facility on plasma thrusters has focused on the effects of background pressure and plume expansion; however, the electrical interaction of the conductive chamber walls with the plasma thrusters needs to be explored further. In this study, the operation of a prototype Hall thruster, HK40, was investigated to understand the effects of wiring configuration of the thruster-cathode-chamber system. During the tests, the thruster was operated in two different grounding configurations. A resistance analogy regarding the changes in the electrical potentials and measured currents was introduced. The calculated thrust and efficiency values of the two configurations were compared. This study shows that the current extracted from the emitter surface of the cathode, along with the cathode-to-ground voltage can be used to estimate the thrust and thruster efficiency. In addition, the theoretical predictions were compared with the values based on the measurements made with an in-house-built inverted pendulum type thrust stand. The presented results show that the thrust and efficiency values are predicted with 3.4% and 8.3% uncertainty, respectively.