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Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article measures and discusses the continuities and changes in the procurement process in Europe by examining the influence of national preferences in terms of sovereignty, industrial issues, and strategic needs on procurement strategies. We focus on the aerospace defense industry and study four aircraft markets (fighter aircraft, transport aircraft, helicopters, and UAVs) in 30 European countries during the post-Cold War era. Our results reveal significant heterogeneity in terms of strategies. They suggest that European countries lack coordination in their aircraft procurement strategies; if a country has sufficient industrial capacity, it will seek to maximize national industrial benefits in its procurement choices, to the detriment of its European partners; conversely, if a country has no industrial capacity, transatlantic suppliers would be preferable to European ones. Members of the former USSR and Warsaw Pact have phased out old Soviet-era aircraft at different rates, depending on the market, with European suppliers benefiting more from this process than American ones. Overall, our study provides a comprehensive and nuanced perspective on the defense aircraft industry in Europe that can inform policymakers and stakeholders in this sector. [ABSTRACT FROM AUTHOR]

This article aims at the development of a generic framework for estimating trade-offs between cost and availability at the equipment level due to corrective maintenance in aircraft maintenance, repair, and overhaul (MRO). The research focuses on closed-loop learning, testing, and validating the proposed framework in a South Asian military aircraft MRO organization. The methodological development of this study is based on soft system methodology through practice-based research. A dynamic simulation has been used to represent the trade-off between availability and cost after the study of more than five hundred corrective maintenance cases for impact analysis. The developed model has been tested for the fix, Gaussian, and triangular distribution in an aircraft MRO shop to calculate the liquidity damage cost due to delivery overrun of equipment. Simulation results of multiple queues indicate that input distribution plays a significant role in the trade-off between the cost and availability of LRUs in aircraft MRO. Academically, this is the first study focussing on the impact of multiple queuing distributions on cost and equipment availability in military aircraft MRO. The proposed framework may help in more precise projection in MRO scheduling, benchmarking, and decision-making while signing the commercial contract between the original equipment manufacturer and the customer. [ABSTRACT FROM AUTHOR]

There is a growing need for electrical power due to increased challenging electrical characteristics of newly developed avionics and mission system equipment in aircrafts. Therefore, with the development of More Electric Aircraft (MEA) and All Electric Aircraft (AEA) concepts, the problem of optimizing and modernizing the electrical power distribution system should be resolved with taking into consideration the weight constraint. In order to deal with this growing demand, power system architectures based on high voltage (270 VDC) and state-of-the-art power electronic devices are being applied to aircraft electrical power distribution systems. Accordingly, this paper evaluates the MEA concept and development in power electronics, conceptual design constraints of the power distribution system and lastly, contributions of 270 VDC distribution and state-of-the-art power electronics at the conversion level. The candidate MEA power distribution system is applied to the conceptual design of the Hercules C-130 Aircraft. The results illustrate that the proposed modernization approach has a positive impact on the total weight, volume, system reliability, electrical protection, and electrical power management system of the aircraft.

Aircraft maintenance order specifies all preventive maintenance tasks involved in aircraft basic level maintenance. During the beginning of aircraft service,the maintenance tasks are intended to be conservative. With the accumulation of aircraft use and maintenance experience,the demand for optimization of maintenance task interval is becoming more and more obvious. Taking the service data as the analysis object and the system reliability as the measurement standard,the optimization analysis method of preventive maintenance task interval is constructed and a realizable mathematical model is formed in this paper. Taking a maintenance task as an example,its service data are analyzed and suggestions on maintenance interval optimization are given. The example has proved the feasibility of the mathematical method and model which can be used as a reference for military aircraft maintenance task interval optimization analysis.

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Digital system has been a part of human life since the invention of the computer with a microprocessor as the central brain. At the heart of a processor is an Arithmetic Logic Unit (ALU) that handles arithmetic and logic operations. The need for high-speed computation to handle complex computations demands microprocessors with higher performance. The existing 4-opcode 8-bit ALU cannot handle multiplication operations, so a solution is needed. In this research, while raising the appeal of beginners, a 12-bit ALU with eight operation codes (opcode) was designed and implemented in Xilinx’s Field Programmable Gate Array using a schematic diagram approach through logic gates. The designed and implemented ALU provides addition, subtraction, multiplication, square, AND, OR, NAND, and XOR operations. The multiplication operation was tested by performing the computation to provided datasets to obtain the distance travelled by ten military aircraft based on their maximum speed and air travel duration to ensure its performance. The computation performance comparison with an 8-bit ALU with four opcodes was also done. The computation was done for air travel between 10 to 60 minutes with a 10-minute difference. It was found that the 12-bit ALU with eight opcodes outperformed its contender with computation differences between 130.815 ns and 1,468.214 ns. This high performance is supported by the multiply operation that does repeated addition at one time. Based on this finding, the 8-opcode 12-bit ALU is more efficient in the context of computation time, with consistent accuracy. Moreover, the computation time required to calculate military aircraft data with different maximum speeds and air travel duration is only 119.501 ns.

This article presents the first demonstration of navigation with cellular signals of opportunity (SOPs) on a high-altitude aircraft. An extensive flight campaign was conducted by the Autonomous Systems Perception, Intelligence, and Navigation Laboratory in collaboration with the U.S. Air Force to sample ambient downlink cellular SOPs in different regions in Southern California, USA. Carrier phase measurements were produced from these signals, which were subsequently fused in an extended Kalman filter along with altimeter measurements to estimate the aircraft’s state (position, velocity, and time). Three flights are performed in three different regions: 1) rural, 2) semiurban, and 3) urban. A multitude of flight trajectories and altitudes above ground level (AGL) was exercised in the three flights: 1) a 51-km trajectory of grid maneuvers with banking and straight segments at about 5,000 ft AGL, 2) a 57-km trajectory of a teardrop descent from 7,000 ft AGL down to touchdown at the runway, and 3) a 55-km trajectory of a holding pattern at about 15,000 ft AGL. The estimated aircraft trajectory is computed for each flight and compared with the trajectory from the aircraft’s onboard navigation system, which utilized a GPS receiver coupled with an inertial navigation system and an altimeter. The cellular SOPs produced remarkable sustained navigation accuracy over the entire flight trajectories in all three flights, achieving a 3D position root mean-squared error of 10.53 m, 4.96 m, and 15.44 m, respectively. [ABSTRACT FROM AUTHOR]

Laser additive repair technology is suitable to repair the metal parts of military aircraft. It is an important thrust to prolong the flight service life and improve the ability of independent maintenance. This paper introduced the characteristics of laser additive repair technologies such as selective laser melting forming, laser direct deposition forming, laser cladding and laser arc composite additive manufacturing. The common types of defects with different scales, such as edge collapse, surface spheroidization, porosity and crack in the process of laser additive repair were described, and the corresponding control methods were proposed. The laser energy density, overlap ratio, feeding speed of filler materials, shielding gas flow, time parameters and scanning path of laser additive repair technology were summarized, and the repair performance was improved by the application of external energy field and optimization design of special filler materials. Finally, the application of laser additive repair technology in the maintenance of aircraft wing beams, turbine blades, single crystal blades, landing gear and other metal parts was listed. The future research trend of laser additive repair technology in auxiliary system design, multi energy field fusion, evaluation standard formulation was emphasized, the research and development of mobile laser additive repair equipment were discussed.

Recently, advanced ground-to-air missiles are developed to defend against a targeted aircraft. A conventional ground-to-air missile has infrared (IR) seekers or radar sensors. However, an anti-aircraft missile based on infrared images is easily distracted by flares, thus an aircraft deploys flares when an incoming missile is detected. In this paper, we propose a missile seeker that complements the weakness of the existing IR sensors, by switching to camera sensors in the case where IR sensors are disturbed. As we switch to camera sensors, we generate the initial bounding box by applying simple line detection algorithms on the target image. Once a bounding box is generated at the target aircraft, the box is tracked continuously using object trackers, which are based on camera images. The missile then uses the bounding box for tracking the target continuously. The object tracker is based on the camera image and is not disturbed by flares or chaffs. To the best of our knowledge, our paper is unique in proposing a missile seeker that complements the weakness of the existing IR sensors, by switching to camera sensors in the case where IR sensors are disturbed. The proposed tracking algorithm is simple and computationally efficient, thus is suitable for real time applications. As far as we know, our tracking algorithm is novel in using simple line detection algorithms for tracking a target aircraft. Using experiments, we show that the proposed tracking method outperforms the-state-of-the-art on object detector considering both time efficiency and tracking accuracy.

The purpose of this study is to highlight the peculiarities of the development of the Russian aviation industry during the First World War. The focus is on analyzing production programs and matching their quantitative and qualitative parameters to war requirements. The main methods used in our work are problem-chronological, used to describe the state of the Russian aviation industry, and comparative, used to compare the level of development of the Russian aviation industry with other countries that participated in the First World War. General scientific methods have also found their application ‒ primarily, analysis and synthesis. The research resulted in the following conclusions: First World War became a challenge for Russian industry that was in the developing stage, including aviation industry. Needs of the front demanded for increase in plane productions that was a complex task for Russia, taking into account its economic backwardness. Aviation industry, being represented by several big (in the scope of Russia) enterprises, demonstrated a dynamic of growth. For the war period the plane production capacity had increased only in 3 times while in Germany – in 10 times and in France and Great Britain the growth was much bigger. Leading enterprises of aviation industry, such as factory of Duks, Liebiediev, Anatra, Shchetinin – mainly copied foreign samples (French, and sometimes German). Efforts to establish the production of original samples were a complete failure. The most known example is fighter “Illia Muromets” that was a leading one in 1914 but became old-fashioned till 1917. Aviation engine production was also narrow and was far beyond plane production. Enormous investments made in the development existed and building of new enterprises of planes and aviation engines production in 1916‒1917 did not show any results, none of the enterprises started the production. We have analyzed some of these failures – building of Anatra factory in Simferopol and Matias factory in Berdiansk, and aero-motors factories Anatra in Simferopol and Deka in Aleksandrovsk. State police on controlling aviation industry based on providing subsidies and preferential loan, turned to be ineffective – it was vanished by basic purchasing prices that did not count on inflation. That is why Russian aviation industry appeared to be unable to face and respond to war challenges. Production plans of leading Russian aviation factories as well as qualitative and quantitative parameters of products have been analyzed in the article.

Introduction/purpose: The use of modern military aircraft requires an extraordinary effort of human and material potential to ensure the conditions for the execution of specific tasks. Complex technology, different spatial and temporal conditions of aircraft use impose the need to create organizational and technical conditions to assist the pilot during flight with the aim of safely and completely accomplishing the flight task. The aim of this paper is to identify possible problems in the organization of the flight safety system through the description of the influence of technical factors on flight safety and to find the best solutions for overcoming problems during the life cycle of the aircraft. Methods: In the research of the subject area, first of all, the analysis of the regulations regulating the field of flight safety was carried out, and then a description of the technical means and their impact on flight safety was carried out. Results: On the basis of the performed analysis, the activities to ensure the reliability of the aircraft during development and production were defined, and directions for improving flight safety were proposed through the amendments of regulations, organizational and technical as well as technological measures. Conclusion: The results of the analysis confirm the assumptions about the possible directions of development and improvement of flight safety of military aircraft through improvement and installation of technical systems (devices and equipment), both aviation and ground.

This paper presents the authors’ recent documentary research on the benefits of using LED lighting products for military aircraft for high-speed take-offs, landings, and taxiing. LED lighting products offer numerous advantages over conventional incandescent aircraft bulb lighting (Halogen and Xenon bulb-based lighting technologies). In terms of energy consumption, LED lighting products are ten times more efficient than incandescent lighting, designed and produced to consume much less electricity than conventional lighting, and do not require a high voltage external power supply. LED lights maintain their full light output even at lower aircraft engine rotation. The LED lights are solid-state mounted devices that can tolerate high levels of shock and vibration without failing. The LED lights for high-speed take-offs, landings, and taxiing offer extraordinary performance that will truly transform the flying experience during nighttime.

Copyright of Journal of Aeronautical Materials is the property of Editorial Board of Journal of Aeronautical Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aviation system has experienced an increasing demand over the last decade since it is considered one of the optimal means of transportation. As a result of this increasing demand, aviation organizations have been forced to focus on passenger safety by keeping aircraft airworthy at all times and by investing in the maintenance sector. Recent literature shows that the maintenance sector is still using outdated technology to maintain documentation of an aircraft's maintenance system. This article proposes the use of model-based system engineering (MBSE) as an approach to document aircraft maintenance systems. Systems modeling language (SysML) provides the maintenance system with a more systematic application that would automatically update maintenance records and provide stakeholders with more precise documentation. SysML is expressed through the use of structural and behavioral diagrams for the EA-6B aircraft. This article also provides a look into the use of SysML in the modeling of complex system architecture and the interaction between various systems. The integration of reliability studies and SysML is showcased through a case study. A failure mode and effect analysis is performed to show the usability of SysML in conducting reliability analysis. This article serves as a foundation for practitioners who aim to use MBSE methodology to solve the current setbacks existing in the maintenance aviation sector. [ABSTRACT FROM AUTHOR]

The KC-135R Stratotanker is a multifunction slim body aircraft that provides air refueling and airlift for the United States’ war and peacetime requirements, which demand a certain level of availability. As the KC-135R fleet ages, the aircraft availability (AA) rate degrades due to high demand use, stress, and the age of the equipment. Preventative and corrective maintenance is designed to return the aircraft to an available state to meet mission requirements, but the United States Air Force continues to fail at meeting every requirement communicated by commanders for KC-135R air refueling and airlift. Focusing on aircraft metrics can enable a prediction model of AA and provide the unit commanders the tools for data influenced decisions. The analysis of historical aircraft maintenance and flight metrics will show a correlation between tracked metrics and AA, thus, the ability to predict a future availability rate. Furthermore, analyzing the data with machine learning techniques will improve prediction accuracy by evaluating the variable importance and will make inferences learned from mining the data that are otherwise difficult to model in a complex system of systems. [ABSTRACT FROM AUTHOR]

Military technologies are typically the product of long-term development efforts. These technologies are often adapted late in the development process for use by other users, including other members of the defense enterprise, foreign militaries, or the commercial sector. The need to adapt a technology can arise from cost over-runs or changing operational requirements. This article describes a value-based methodology for developing a transition plan early in the development process, when the system is still in the conceptual phase. Performing this analysis early in the design phase allows for design choices that will support adapting the system for other users. Moreover, it provides a risk mitigation strategy against cost over-run and changes in operational requirements. The process begins by capturing the functional architecture of the technology and analyzing them against a set of tasks associated with different military positions. From there, the adapted technology is evaluated for its projected adequacy based on the value added and the effort required for adaptation. The end-state of this analysis is a value-based model that identifies a portfolio of possible alternative markets and/or uses, which can be comparatively analyzed. A case study is presented for adapting a military augmented reality system for a different market. [ABSTRACT FROM AUTHOR]

This paper presents the authors’ recent documentary research on the benefits of using the Fly-by-Light system in Military aircraft and the understanding of why Fly-by-Light (FBL) is very promising for the further development of military aircraft. The Fly-by-Light flight system is characterized by the fact that the input control signals from the pilot, motion data, and air data sensors are sent to the flight control computer and from there to the actuators of the control surfaces through a fiber optic cable and the feedback from actuators sensors or other signals is received in the same way, through fiber optic cable connected to the aircraft flight control computer. The first major step in the evolution of flight control systems was the replacement of mechanical flight control systems with a Fly-by-Wire (FBW) flight control system. The next major step is the replacement of Fly-by-Wire (FBW) flight control system with a Fly-by-Light (FBL) flight control system which has some significant advantages such as: reducing the weight of the system, increasing the speed and volume of information transmitted through fiber-optic cable (input and feedback signals), keeping intact the accuracy of the signals along the entire length of the circuit; also, the optical fibers do not present any risk of fire, as they carry only light signals, and the temperature, humidity, and severe weather conditions do not affect the fiber optic cable, which can withstand a pressure of about 0.69 - 1.38 MPa without damaging the cable, unaffected by Electromagnetic Interference (EMI) and the Electromagnetic Pulse (EMP) generated by nuclear blasts. All the advantages listed above provide tactical and safety advantages for the military aircraft and its crew.

In the final assembly stage of military aircraft,there are problems of high control cost caused by the disconnection between quality control and business process and the lack of advanced quality planning. To solve these problems,insufficient quality planning and high control costs in the military aircraft final assembly stage,APQP(Advanced Product Quality Planning)application guide suitable for the military aircraft final assembly stage is proposed by improving the APQP guidance material of the IAQG(International Aerospace Quality Group),including theoretical models,core content and key elements,etc. The application effect of the military aircraft assembly APQP in process optimization and management,risk identification and control are verified on the aero-engine installation. The results show that the military aircraft assembly APQP is beneficial to predict and reduce risks,reduce process changes,improve military aircraft quality and delivery efficiency.

Introduction/purpose: The use of modern military aircraft requires an extraordinary effort of human and material potential to ensure the conditions for the execution of specific tasks. Complex technology, different spatial and temporal conditions of aircraft use impose the need to create organizational and technical conditions to assist the pilot during flight with the aim of safely and completely accomplishing the flight task. The aim of this paper is to identify possible problems in the organization of the flight safety system through the description of the influence of technical factors on flight safety and to find the best solutions for overcoming problems during the life cycle of the aircraft. Methods: In the research of the subject area, first of all, the analysis of the regulations regulating the field of flight safety was carried out, and then a description of the technical means and their impact on flight safety was carried out. Results: On the basis of the performed analysis, the activities to ensure the reliability of the aircraft during development and production were defined, and directions for improving flight safety were proposed through the amendments of regulations, organizational and technical as well as technological measures. Conclusion: The results of the analysis confirm the assumptions about the possible directions of development and improvement of flight safety of military aircraft through improvement and installation of technical systems (devices and equipment), both aviation and ground. [ABSTRACT FROM AUTHOR]

Opportunistic navigation with cellular signals is studied and demonstrated on a high-altitude aircraft. An extensive campaign was conducted by the Autonomous Systems Perception, Intelligence, and Navigation Laboratory (ASPIN) in collaboration with the U.S. Air Force (USAF) to sample ambient cellular signals of opportunity (SOPs) at different altitudes in different regions in Southern California, USA. The carrier-to-noise ratio is characterized as a function of altitude and horizontal distance. It was found that signals from cellular transmitters can be reliably acquired and tracked for navigation purposes by receivers mounted on high dynamics aircraft flying at altitudes as high as 23,000 ft above ground level and horizontal distances as far as 100 km. The multipath channel is also characterized as a function of altitude, showing clean channels with a dominant line-of-sight component for altitudes up to 23,000 ft. To further assess the potential of cellular SOPs for aircraft navigation, a 51-km trajectory traversed over a period of 9 minutes was estimated exclusively using cellular SOPs (i.e., with no GPS or other sensors, except for barometric altimeter measurements), resulting in a three-dimensional position (3-D) 10.5-m position root-mean-squared error. [ABSTRACT FROM AUTHOR]

A search vehicle routing algorithm is presented, inspired by thermalling in glider operations, for use in unmanned aerial vehicle (UAV) search routing problems where radio frequency signal noise affects target geolocation. We conduct ground testing experiments and observe that signal strength significantly deviates from its mean value — 10-20% variation in our experiments — at each distance epoch away from a target of interest. The thermalling algorithm uses straight-line segments and relatively simple guidance logic to generate routes that appear promising for fixed-wing, short endurance and autonomous UAV routing applications. We compare the simulated performance of the thermalling algorithm to a stochastic gradient descent algorithm using 1,000 randomly generated problem instances and show that, when considering signal readings and distance traveled as performance metrics, the thermalling algorithm performs better in 100% and 37% of problem instances respectively. [ABSTRACT FROM AUTHOR]

Because the Polish Air Force currently uses F-16 and MiG-29 aircraft, the aim of the study was to conduct a comparison of the susceptibility to destruction in combat of these two aircraft. The first part of the work concerned the analysis of individual critical components, such as: general characteristics of the airframe structure, aircraft engine, flight control system, fuel system, aircraft weapons, radar system. The index of susceptibility to destruction in combat was defined considering the listed critical components and the following types of enemy weapon: aircraft gun, air-to-air missile, anti-aircraft gun, surface-to-air missile. The analysis proved that the aircraft have similar susceptibility to damage in combat, a slight advantage of the F-16 aircraft in this respect was determined. The presented scheme can be used to analyze other aircraft. Proposals of aircraft modifications, directions of further actions, possibilities of using the described method were presented. The method can be used to making decisions by governments regarding the purchase aircraft for their fleets and identify aircraft critical components with high susceptibility to destruction in order to introduce appropriate modifications by military aircraft manufacturers.

Automatic Carrier Landing System With Fixed Time Control [ABSTRACT FROM AUTHOR]

A controller that uses sum-of-squares programming is proposed for the attitude control of fixed-wing aircraft. Firstly, the vehicle’s state space form of attitude model is obtained by utilizing general mechanics. Then an online compute controller is designed to achieve the desired attitude tracking performance by solving contraction control metric related to the linearization area near the equilibrium point. Finally, the effectiveness of the control algorithm is demonstrated by a comparative simulation experiment. [ABSTRACT FROM AUTHOR]

Because the Polish Air Force currently uses F-16 and MiG-29 aircraft, the aim of the study was to conduct a comparison of the susceptibility to destruction in combat of these two aircraft. The first part of the work concerned the analysis of individual critical components, such as: general characteristics of the airframe structure, aircraft engine, flight control system, fuel system, aircraft weapons, radar system. The index of susceptibility to destruction in combat was defined considering the listed critical components and the following types of enemy weapon: aircraft gun, air-to-air missile, anti-aircraft gun, surface-to-air missile. The analysis proved that the aircraft have similar susceptibility to damage in combat, a slight advantage of the F-16 aircraft in this respect was determined. The presented scheme can be used to analyze other aircraft. Proposals of aircraft modifications, directions of further actions, possibilities of using the described method were presented. The method can be used to making decisions by governments regarding the purchase aircraft for their fleets and identify aircraft critical components with high susceptibility to destruction in order to introduce appropriate modifications by military aircraft manufacturers. [ABSTRACT FROM AUTHOR]

An all-textile cavity-backed substrate integrated waveguide (SIW) antenna is proposed for military applications. The antenna matches standard military badge size. The aircraft-shape badge antenna that operates in X-band is designed for air force. SIW cavity and meandered slots that form the body and wing of the figure provide resonance at 8 GHz with 26% bandwidth. Symmetrical boresight patterns with very low sidelobes are observed. The measured gain and efficiency of the structure are 5.2 dBi and 79.2% at 8 GHz, respectively. This efficiency value is the highest among other SIW cavity textile-antennas. The antenna is investigated on conformal surfaces, as well. Bending of the antenna to follow body movements does not deteriorate performance of the textile antenna sensor. The peak specific absorption rate value over 10 g of tissue was 0.53 and 0.69 W/kg for 30 dBm input power for female and male breasts, which makes it suitable as an on-body antenna. The badge antenna is fabricated with standard textile fabrication techniques and its simulation performance is confirmed successfully by measurements. Usage of standard off-the-shelf parts for the assembly and fabrication with standard textile fabrication techniques enables simple and cost-effective mass production of the proposed badge antenna. [ABSTRACT FROM AUTHOR]

Copyright of Knowledge: International Journal is the property of Institute for Knowledge Management and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the authors' recent documentary research on the benefits of using LED lighting products for military aircraft for high-speed take-offs, landings, and taxiing. LED lighting products offer numerous advantages over conventional incandescent aircraft bulb lighting (Halogen and Xenon bulb-based lighting technologies). In terms of energy consumption, LED lighting products are ten times more efficient than incandescent lighting, designed and produced to consume much less electricity than conventional lighting, and do not require a high voltage external power supply. LED lights maintain their full light output even at lower aircraft engine rotation. The LED lights are solidstate mounted devices that can tolerate high levels of shock and vibration without failing. The LED lights for high-speed take-offs, landings, and taxiing offer extraordinary performance that will truly transform the flying experience during nighttime. [ABSTRACT FROM AUTHOR]

Aircraft detection in synthetic aperture radar (SAR) imagery is a challenging task in SAR automatic target recognition (SAR ATR) areas due to aircraft’s extremely discrete appearance, obvious intraclass variation, small size, and serious background’s interference. In this article, a single shot detector (SSD), namely, attentional feature refinement and alignment network (AFRAN), is proposed for detecting aircraft in SAR images with competitive accuracy and speed. Specifically, three significant components, including attention feature fusion module (AFFM), deformable lateral connection module (DLCM), and anchor-guided detection module (ADM), are carefully designed in our method for refining and aligning informative characteristics of aircraft. To represent the characteristics of aircraft with less interference, low-level textural and high-level semantic features of aircraft are fused and refined in AFFM thoroughly. The alignment between aircraft’s discrete backscatting points and convolutional sampling spots is promoted in DLCM. Eventually, the locations of aircraft are predicted precisely in ADM based on aligned features revised by refined anchors. To evaluate the performance of our method, a self-built SAR aircraft sliced dataset and a large scene SAR image are collected. Extensive quantitative and qualitative experiments with detailed analysis illustrate the effectiveness of the three proposed components. Furthermore, the topmost detection accuracy and competitive speed are achieved by our method compared with other domain-specific methods, e.g., dense attention pyramid network (DAPN) and pyramid attention dilated network (PADN), and general convolutional neural network (CNN)-based methods, e.g., Feature Pyramid Network (FPN), Cascade R-CNN, SSD, RefineDet, and RepPoints Detector (RPDet). [ABSTRACT FROM AUTHOR]

The essence of this paper is to study and characterise the performance of Indian Regional Navigation Satellite System (IRNSS), also known as NavIC (Navigation with Indian Constellation), in actual dynamic environment by conducting field trials on military aircraft. The dynamic accuracy of IRNSS receiver in terms of position, velocity and altitude has not yet been tested on any aircraft system i.e. commercial or military applications. These field trials and performance evaluation will help in on-field assessment of IRNSS receiver performance with availability of five, six and seven IRNSS satellites. During conduct of trials, IRNSS receiver and IRNSS antenna were placed inside the aircraft. Results analysis of 18 hours flying data depicts position availability of 99.872% with five satellites and 100% position availability with six and seven satellites. [ABSTRACT FROM AUTHOR]

This paper presents the authors' recent documentary research on the benefits of using the Fly-by-Light system in Military aircraft and the understanding of why Fly-by-Light (FBL) is very promising for the further development of military aircraft. The Fly-by-Light flight system is characterized by the fact that the input control signals from the pilot, motion data, and air data sensors are sent to the flight control computer and from there to the actuators of the control surfaces through a fiber optic cable and the feedback from actuators sensors or other signals is received in the same way, through fiber optic cable connected to the aircraft flight control computer. The first major step in the evolution of flight control systems was the replacement of mechanical flight control systems with a Flyby-Wire (FBW) flight control system. The next major step is the replacement of Fly-by-Wire (FBW) flight control system with a Fly-by-Light (FBL) flight control system which has some significant advantages such as: reducing the weight of the system, increasing the speed and volume of information transmitted through fiber-optic cable (input and feedback signals), keeping intact the accuracy of the signals along the entire length of the circuit; also, the optical fibers do not present any risk of fire, as they carry only light signals, and the temperature, humidity, and severe weather conditions do not affect the fiber optic cable, which can withstand a pressure of about 0.69 - 1.38 MPa without damaging the cable, unaffected by Electromagnetic Interference (EMI) and the Electromagnetic Pulse (EMP) generated by nuclear blasts. All the advantages listed above provide tactical and safety advantages for the military aircraft and its crew. [ABSTRACT FROM AUTHOR]

In this second installment about Swedish cryptology, we will describe the successes and failures in intercepting, cryptanalyzing, and reading the secret messages of potentially hostile and other countries during WW2. The information gathered aided the government in its quest to stay neutral and kept the military leadership informed about possible threats of invasion. [ABSTRACT FROM AUTHOR]

Introduction to The Problem: The act of firing on two Indian military aircraft carried out by Pakistan indeed constitutes the right of air control over military aircraft according to the Paris Convention of 1919 and the Chicago Convention of 1944, according to which this convention's control rights over foreign military aircraft are strict and maximum, it does not contain exceptions Article 32 of the Paris Convention and Article 3 (c) of the 1944 Chicago Convention The right of maximum and strict control of the state over its airspace is only directed to military aircraft of other countries, where the consideration of national security is the main reason. But still, the shooting action carried out by Pakistan against Indian military aircraft is an act of negligence on airspace which became its sovereignty, due to the lack of coordination related to the shootings carried out.Purpose/Objective Study: This study aims to determine and understand the regulation of Indian military aircraft in the 1944 Chicago Convention on Flight of Military Aircraft to Airspace in Other Countries and the responsibility of the state of Pakistan in firing Indian military aircraft from the perspective of international air law.Design/Methodology/Approach: This research is research that uses normative legal research methods using a type of legislation approach and case approach. The legal materials used are primary, secondary, and tertiary legal materials that are useful for obtaining conclusions that are relevant to the problems in this study.Findings: The results showed that: 1) the regulation of Indian military aircraft in the 1944 Chicago Convention was categorized as a military aircraft (state aircraft) type of MiG-21 Bison interceptor which was indeed used for military, police and customs purposes, which in this case did not have the right to do flight above the airspace of another country before obtaining permission in advance from the country concerned; 2) the form of responsibility that must be given is in the form of termination of acts, apologies and remedial actions in the form of restitution, ie repairing as before the Indian military aircraft that he shot and providing protection for pilots he captures, this is as regulated in Article 31 of the ILC Draft.Paper Type: Research Article

The military aircraft health assessment has the problem of difficult application in engineering practice. The military aircraft is taken as the research object of health assessment, including task-oriented capability analysis, function analysis based on fault degradation and parametric health assessment. The two-level mapping of "aircraft-mission function-impact parameters" based on mission analysis is obtained as the object of health assessment. The degradation, severity and maximum entropy modification are comprehensively utilized. The results of aircraft health assessment are obtained by interval analytic hierarchy process and other methods. In combination with the specific example object and parameter analysis results, this assessment method has high reliability, and high engineering practical value.

Aquatic unmanned aerial vehicles (AquaUAV) have aroused much attention from researchers, though no fully-featured aerial-aquatic UAV exists so far. The assistance of webbed foot hydroplaning can accomplish rapid take-off of a cormorant. A significant impact force and moment can be generated due to the webbed foot propulsion in the water-to-air transition. However, the change law of force and moment experienced by the cormorant during take-off has not been captured. Based on previous achievements in the biological investigation, we developed a biomimetic prototype with curve fitting model and parameter optimization to attain specific movements to imitate cormorant's hydroplaning strategy. The bionic webbed foot considers the elastic mechanics, and the forepart is regarded as flexible material for fluid-structure interaction (FSI). Dynamic process of rapid take-off in the aspects of flow characteristics and mechanical properties can be estimated by computational fluid dynamics (CFD) in our proposed FSI model, which establishes a foundation for further applications in the design of the assisted propulsion system of aerial-aquatic UAV.

The conventional spherical conformal phased-array antenna (SPAA) has a wide beam coverage but suffers from a high profile due to its spherical conformal carrier. In this article, a low-profile conformal array antenna is modified from the conventional SPAA, which can be called the concave sector-cut spherical phased-array antenna (CSSPAA). A distributed aperture synthesis is employed to guarantee that the performance of the CSSPAA is close to that of the SPAA after reducing its height as much as possible. The CSSPAA’s height and the element’s half-power beamwidth (HPBW) are properly designed to minimize the blockage influence due to the special topology of the CSSPAA. A prototype CSSPAA with 48 elements is designed as an example, and the height of the CSSPAA is 43% lower than that of the SPAA with the similar performance in the hemispherical beam coverage. Both numerical and experimental results indicate the effectiveness of the developed method. [ABSTRACT FROM AUTHOR]

This article proposes a novel image-based visual servoing for a flexible aerial refueling boom with an eye-in-hand camera. The dynamic model of the flexible refueling boom is established by absolute nodal coordinate formulation (ANCF), after which the dynamic model is decomposed into a slow subsystem and a fast subsystem based on the singular perturbation approach. With respect to slow subsystem, the image feedback is used to control the flexible refueling boom so that the projection of the point marker on the back of the receiver converges to the desired position. With respect to fast subsystem, linear quadratic regulator (LQR) is applied to stabilize the vibration of the flexible refueling boom. The asymptotic convergence of the image error to zero is verified based on the Lyapunov theory. Simulation is used to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Before Unmanned Aircraft Systems (UAS) can be widely deployed over complex terrain and urban regions, a methodology is needed to deconflict and track UAS flights. This paper presents a formal geofence definition and a methodology to use geofences to temporally and spatially organize the airspace in support of a UAS Traffic Management (UTM) system. Algorithms are presented to temporally and spatially deconflict requested geofences from existing approved geofences in the UTM system. A case study shows how deconflicted geofences impact UAS flight. [ABSTRACT FROM AUTHOR]