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Regarding the development of an aircraft assembly process, this paper will illustrate the intelligent decision and policies of the aircraft assembly process based on technician experience. A model of the knowledge management system of the aircraft assembly process is developed to avoid the complexity of the entire aircraft or aircraft product assembly process. Firstly, According to the characteristics of the knowledge management system of the aircraft assembly process, the aircraft assembly process has been discussed to realize the decision of the aircraft assembly process. Secondly, intelligent decision-making in the aircraft assembly process has been established based on the knowledge management system and aircraft assembly process library that is oriented to the assembly process requirements employing an assembly process reasoning method.

The fundamental characteristic of aircraft assembly is assembly measurement accuracy. A single digital measurement device can meet the requirements of an analytical and small surface. But a single digital measurement device cannot meet the measurement requirements for synthetic and large surfaces, such as fuselage panel components. This research aims to establish a combined measurement method to improve the measurement quality and extend the measurement area. The method demonstrated the combined measurement method utilizing a combination of the laser tracker and the articulated arm measuring machine. In this research, the combined measurement system is constructed based on the complexity and large size of the fuselage panel. The articulated arm measuring machine is used to scan the surface of the panel components accurately and the coordinate conversion of the common points measured by the laser tracker to realize the shape of the aircraft fuselage panel.

The continued electrification of aircraft is required such that ambitious decarbonisation targets can be met. A significant challenge presented with this trend is the increased reliance on electrical systems to perform flight-critical operations in a manner that has not been seen in previous generations of aircraft. The power electronic converter is a key enabling technology in aircraft electrification. Its prevalence is such that the failure rate of flight critical-loads is closely linked with that of the associated power electronic converters. As such, there is a clear need to better understand the impact of improvements in both the reliability and failure estimation of novel power electronic converters at a systems level in future aerospace applications. Accordingly, this paper presents key highlights from literature on power converter research, summarising advances in reliability-enhancing features and more accurate Physics-of-Failure modelling methods.

An Air Traffic Controller(ATC) is a person responsible for the proper Take-Off and Landing of an Aircraft from the runway, and for relaying continuous vital information back and forth from Pilots. The proposed ATC will automate this entire process to reduce human-generated errors and save costs. The entire system will be made using Artificial Intelligence and will use Natural Language Processing and Artificial Neural Networks to create a human-like, but a better-prepared system. The model needed to create the ATC, can be trained on already available crucial flight data. The data must include flight take-off and landing time, along with altered time based on weather, climate and other physical factors. The back-end system of the ATC, can be then made to work on this trained model, and produce correct and calculated flight path and timings for the take-off and Landing.

The concept of the circular economy provides a framework for a more efficient closed-loop economy. Much literature has been published focusing on circular business models and assessing environmental impact throughout the life cycle. A move towards more circular business models, where the focus transitions to the delivery of a capability rather than the delivery of a product, presents new challenges to manufacturers of complex or certified engineered products. The aviation industry has established several engineering disciplines, life cycle design, and certification approaches that (while not designed with the circular economy in mind) underpin the principles of the circular economy. This paper provides a new conceptual framework for the circular economy that integrates the engineering principles that drive circularity around the life cycle for designing, producing, and operating complex and certified engineering systems.

Aerospace manufacturing is improving its productivity and growth by expanding its capacity for production by investing in new tools and more equipment to provide additional capacity and flexibility in the face of widespread supply disruptions and unpredictable demand. However, the cost of such measures can result in increased unit costs. Alternatively, productivity and quality can be improved by utilizing available resources better to reach optimal performance and react to emerging disruptions and changes. Elastic Manufacturing is a new paradigm that aims to change the response behavior of firms to meet sudden market demands based on automated analysis of the utilization of the available resources, and autonomous allocation of capacity to use resources in the most efficient manner. Through digitalization of the shopfloor, streaming data from equipment enables companies to identify areas for improvement and boost the efficiency without large capital expenditure.

This work covers the historical development of Built-In-Test (BIT) for fiber optic interconnect links for aerospace applications using Optical Time Domain Reflectometry (OTDR) equipped transceivers. The original failure modes found that installed fiber optic links must be disconnected before diagnosis could begin, often resulting in “no fault found” (NFF) designation. In fact, the observed root cause was that most (85%) of the fiber optic link defects were produced by contamination of the connector end faces. In March of 2006, a fiber optics workshop was held with roughly sixty experts from system and component manufacturers to discuss the difficulties of fiber optic test in aerospace platforms. During this meeting it was hypothesized that Optical Time Domain Reflectometry (OTDR) was feasible using an optical transceiver transmit pulse as a stimulus. The time delay and amplitude of received reflections would correlate with the position and severity of link defects, respectively.

This paper focuses on a case study to compare the performances of Fowler wing flaps that are used on the trailing edge of modern-day commercial airliners. The aim is to observe trends in coefficients of lift (Cl) and drag (Cd) with varying flap angles of release on a single-slotted Fowler flap and arrive at the most efficient flap configuration for flight. A series of two-dimensional analyses are carried out using computational fluid dynamics (CFD) to examine the flow separation and occurrence of stalls between the different angles of flap deflection. A two-equation, k-ω shear stress transport (SST) turbulence model is used as it helps in better prediction of flow separation and boundary layer studies. Since the study is carried out for such passenger carriers, the study focuses on the lower transonic ranges of Mach number 0.7-0.9 with a Reynolds number range of 400,000 to 500,000 considering a scaled-down model and upon taking inspiration from related literature.

Most of current jet aircraft circulate fuel on the airframe to match heat loads with available heat sink. The demands for thermal management in wide range of air vehicle systems are growing rapidly along with the increased mission power, vehicle survivability, flight speeds, and so on. With improved aircraft performance and growth of heat load created by Aircraft Mounted Accessory Drive (AMAD) system and hydraulic system, effectively removing the large amount of heat load on the aircraft is gaining crucial importance. Fuel is becoming heat transfer fluid of choice for aircraft thermal management since it offers improved heat transfer characteristics and offers fewer system penalties than air. In the scope of this paper, an AMESim model is built which includes airframe fuel and hydraulic systems with AMAD gearbox of a jet trainer aircraft. The integrated model will be evaluated for thermal performance.

The aerospace industry is undergoing a revolution with the large-scale development of eVTOL (Electric Vertical Take-Off & Landing) and MEA (More Electric Aircraft). These aerial vehicles, many of them unmanned vehicles (UAV), will serve a variety of service-related functions: Search and Rescue (SAR), Medivac, delivery and lift operations, aerial mapping, and, of course, human transportation [1]. Despite its numerous functionalities, this type of vehicle has a serious problem, which is its usual batteries, the main means for its operation. Due to its autonomy not being so effective compared to its charging time, generating a considerable loss of time. In this context, it is necessary to find forms of components that can replace these batteries, so that the effective development of these vehicles is possible. Studies done in other means of transportation point out that the use of hydrogen fuel cells has grown a lot.

Equipment used in aerospace non-destructive inspection presents opportunity for modernization. Many inspection cells in production operate using a widely available control system software that is suitable for most inspection applications with minimal customization. The size and complex geometry of airframe components demand more application-specific system design to ensure the reliability and cycle time required for an aerospace production schedule. Ordinary inspection systems require manual teaching for program generation and lack datum-finding systems required to rerun programs without modification. Integration of offline programming software and machine vision instruments can save inspection technicians hours or shifts per part by eliminating the need for program retraining due to variation in part delivery position. Modernized inspection cells will reduce labor burden on technicians and provide reliable cycle time information to production planners.

As the aerospace industry moves toward determinate assembly and ever-tighter manufacturing tolerances, there is a need for automated, high-precision milling, trimming and drilling equipment that is specialized for aerospace applications. Precision countersinking is a common requirement for aircraft parts, but this is not a process that typical general-purpose milling machines are able to accommodate without the use of specialty tools such as depth-stop tool holders. To meet this need, Electroimpact has designed a 5-axis milling machine with high-speed clamping capability for countersink depth control. A custom trunnion and head with a quill and an additional clamp axis provide clamping functionality similar in speed and precision to a riveting machine, while maintaining the accuracy and features of a conventional machining center.

Refueling operation of the aircraft fuel tanks has some limitations. One of the limitations is refueling time which restricts refueling duration for entire tank. Other one is overfilling situations which are also possible because of the wave damper designs in tank such as barriers and baffles resist against fuel creeping towards all sides of tank. Required refueling duration restricts refueling speed at a certain minimum value. On the other hand, baffle design restricts refueling speed at a certain maximum value. It should be the mathematical region between these two extremum points where the refueling mass flow rate can be defined. Minimum mass flow rate point can be adjusted with defining of mass flow rate depends of requirements easily but upper extremum point should be defined depends on design of baffles. It can only be changed with altering the design of interior wing tank.

In this work we discuss the fault avoidance and the fault tolerance approaches for increasing the reliability of aerospace and automotive systems. This includes: the basic definitions/concepts (reliability, maintainability, availability, redundancy, etc.), and characteristics (a priori analysis, a posteriori analysis, physical/hardware redundancy, analytical/software redundancy, etc.) of both approaches, their mathematical background and models (exponential, Weilbull, etc.), their basic theory, their methods and techniques (fault trees, dependence diagrams, Markov chains, etc.), some of their standards (SAE-ARP4761, AC 25.1309, etc.) and simulation environments (Cafta, etc.), and their applications to the reliability analysis and reliability improvement of aerospace and automotive vehicles. This is illustrated by some examples driven from the aerospace and automotive industries.

With the growing complexity and integration of systems as satellites, automobiles, aircrafts, turbines, power controls and traffic controls, as prescribed by SAE-ARP-4754A Standard, the time de-synchronization can cause serious or even catastrophic failures. Time synchronization is a very important aspect to achieve high performance, reliability and determinism in networked control systems. Such systems operate in a real time distributed environment which frequently requires a consistent time view among different devices, levels and granularities. So, to guarantee high performance, reliability and determinism it is required a performance evaluation of time synchronization of the overall system. This time synchronization performance evaluation can be done in different ways, as experiments and/or model and simulation.

Aerospace Recommended Practice (ARP) 4754 Revision A (ARP4754A), Guidelines for Development of Civil Aircraft and Systems [1], and ARP4761, Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment [2], together describe a complex set of intertwining processes which comprehensively prioritize development activities for a product's systems based on their safety criticality. These processes work at specific levels of detail (aircraft and system) and interact with a set of processes at lower levels of detail (item) defined by Radio Technical Commission for Aeronautics (RTCA) standards. The aircraft and system development process (ARP4754A) supplies functions, requirements, and architectural definitions to the System Safety process (ARP4761), which in turn supplies Development Assurance Levels back to the development process and on to the RTCA processes.

The advent of the Covid-19 pandemic that began at the end of 2019 accelerated technology to support remote work environments. While the technologies were not new, the capabilities of those technologies significantly increased. The number of users embracing the remote working technologies significantly increased within a very short timeframe. The expanded remote work capabilities have enabled new collaborating mechanisms that will carry-forth in the future, pandemic or not. SAE ARP 4761 [1] provides guidelines to perform a safety assessment. The Zonal Safety Assessment (ZSA) is one of the tools described in ARP 4761. An aspect of ZSA is an audit (or inspection) of the physical article. The remote work capabilities, along with cameras and software presenting a virtual environment, can allow individuals to participate in the physical audit without traveling to the site of the physical article.

This paper presents a summary of a university based research project sponsored by Honeywell for the development of sensorless control method for Brushless DC (BLDC) motors for industrial and aerospace applications. In particular, the development, test results and assessment of an advanced cost effective sensorless BLDC motor controller for aerospace applications are presented and discussed in detail. The motor is controlled by the method of detecting the back EMF instead of the usage of the rotor position or speed sensors. The implemented embedded controls utilize an ASIC with the main objective of enhancing reliability, fault-tolerance, power density and performance.

This paper first reviews the application of fault-tolerant machine drives as a means of reaching the necessary reliability levels in aerospace applications with minimum weight penalty. The requirements of such machines will be reviewed and different motor topologies will be compared. Three examples of fault-tolerant drive system demonstrators will then be described including a novel flux-switching, permanent magnet, synchronous machine topology.

This paper presents the design, fabrication, and testing of a 50HP, 30000 rpm induction motor for a next generation large aircraft spoiler. The motor is characterized by high power density, developing over 8.5 pounds per square inch of airgap surface area with only 13 pounds electromagnetic weight. Detailed designs, including magnetic material selection, electromagnetic parameters, and finite element thermal analyses are presented and compared to test data. Testing was obtained using a high speed hydraulic dynamometer with digital data acquisition. The motor and actuator are designed and built by AlliedSignal for participation in the NASA Redundant Effector Program and NASA Power-by-Wire Electromechanical Actuation (EMA) Spoiler Program. The program emphasizes the demonstration of power electronic motor drive and actuation technologies for aerospace applications.