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The aircraft jet engine is one of the most complex multivariable systems with multiple inputs and multiple outputs. To attempt to optimize control functions or to address diagnostic problems, a detailed knowledge of all jet engine design parameters and performances is required. Although jet engines have been around for almost a century, there are only a few companies in the world presently designing and manufacturing them; as such these companies possess detailed knowledge of all relevant design characteristics and performance parameters. In the event where jet engine technical details are unknown, or only a few of them are known from manufacturer’s catalogues, the challenge becomes how to calculate and extrapolate critical performance parameters based on only fuel flow, jet exhaust temperature and total thrust.

In recent years, the increasing complexity of modern aerospace systems has driven the rapid adoption of robust Model-Based Systems Engineering (MBSE). MBSE is a development methodology centered around computational models, which are instrumental in supporting the design and analysis of intricate systems. In this context, the Architecture Analysis and Design Language (AADL) and Systems Modeling Language (SysML) are two prominent modeling languages for specifying and analyzing the structure and behavior of a cyber-physical system. Both languages have their own specific use cases and tool environments and are typically employed to model different aspects of system design. Although multiple software tools are available for transforming models from one language to another, their effectiveness is limited by fundamental differences in the semantics of each language.

In the development of electric actuators, the electric motor to drive the actuator is quite often selected from a set of available motors that have been previously used on other similar programs, or based on legacy experience, or from those that are commercially available seeming to fit for the purpose. Scheduling and budgetary constraints pose a restriction on design and development of a new electric motor specifically for the required application. Generally, these electric motors have minimal weight but deliver maximum output power because of which they tend to heat up rapidly. Such rapid heating can lead to issues such as insulation damage or weakening of the strengths of permanent magnets used in the rotors of permanent magnet induction motors. In such cases, very early in the design phase, it becomes necessary to estimate the temperature rise of the electric motor in a cost effective and rapid way so that the best suitable motor that gives minimal temperature rise is selected.

Aircraft Manufacturing procedures are very critical which always require skillful engineers who must adhere to various process and procedure during daily work. The challenge is not only to identify right tools and manuals but also to keep track of operator usage data and behavior. With Augmented reality (AR), intelligent tools and analytics, we can provide a new lease of life to first-line assembly engineers. The objective is how AR can help us to reduce rework or scrap with the concept of Industry 4.0 [1] were integrating with cutting edge technologies like machine learning and the internet of things (IoT) to meet the fundamental requirements during manufacturing. Smart Manufacturing consists of four major components Cyber-physical systems, IoT, cloud computing and cognitive computing.

Evolving of aircraft design towards further electrification requires safe and fault-free operation of all the components. More electric aircraft are increasingly utilizing electro-mechanical actuators (EMA). EMAs are prone to jamming and subsequent failure due to large forces on the shaft. Large forces are generated due to the high reflected inertia of the electric machine rotor. To limit the force acting on the shaft, a torque limiting device is connected to the power train which can separate the rotating mass of the electric machine from the power train. In this paper, a concept of integration of torque limiter and the electric machine rotor is presented to reduce overall volume and mass. It is connected closely with the rotor, within the motor envelope. A commercially available torque limiter and an electric machine designed for actuator application are used to demonstrate the concept. While essential for safety, the torque limiter adds to the mass and size of the overall EMA.

Since the early days of aviation, when an AC-type generator became a primary source of electrical power for all aircraft systems, the demand for electrical power has steadily grown. Following rapid technology and scientific advancements in the aerospace industry, the complexity and criticality of all aircraft systems have increased to the point where multiple independent and isolated electrical power sources are required. In such an environment, with two or more variable-frequency AC-type generators that can be simultaneously activated to provide electrical power to the aircraft power distribution system, a safe power transfer process becomes a major priority. This means that any two independent aircraft AC power sources with different frequencies or phase angles cannot be connected simultaneously to a common power bus.

Unmanned Aircraft Systems (UAS) have been growing over the past few years and will continue to grow at a faster pace in future. UAS faces many challenges in certification, airspace management, operations, supply chain, and maintenance. Blockchain, defined as a distributed ledger technology for the enterprise that features immutability, traceability, automation, data privacy, and security, can help address some of these challenges. However, blockchain also has certain challenges and is still evolving. Hence it is essential to study on how blockchain can help UAS. G-31 technical committee of SAE International responsible for electronic transactions for aerospace has published AIR 7356 [1] entitled Opportunities, Challenges and Requirements for use of Blockchain in Unmanned Aircraft Systems Operating below 400ft above ground level for Commercial Use. This paper is a teaser for AIR 7356 [1] document.

The accurate prediction of system behavior and the stress response for vibration loads depends on how well the boundary conditions, joints, interfaces, mass, and stiffness are defined. Often, in vibration analysis several assumptions would be made due to the lack of the analytical tool capabilities, the state of art Finite Element Analysis (FEA) software still cannot handle nonlinear modal analysis. This paper attempts to develop methodology to deal with the nonlinear vibration analysis using the existing Finite Element (FE) tools. Two different aspects of nonlinearities are considered, one is impact of nonlinearities at global level in terms of predicting natural frequency & mode shapes and the other aspect is consideration of nonlinearities local to the contacts, enabling prediction of realistic stresses in the vicinity of the contacts.

The FE analysis of complex systems with lot of intricate features and fillets modeled in detail would result in a huge FE model size making it difficult to handle. Therefore, to reduce the computation time, defeaturing of such regions are carried out as a common practice and these critical stress concentration regions can be studied using submodeling approach later based on response superimposed from the global models. This method is widely practiced and is quite easy to implement for static and harmonic analysis problems. However, there is no well documented methodology exists for submodeling in the random vibration environment. In case of Random vibration analysis, the cut boundary displacements from Power Spectral Density (PSD) analysis would result in unrealistic stresses.

For nearly a century, ice build-up on aircraft surfaces has presented a safety concern for the aviation industry. Pilot observations of visible moisture and temperature has been used a primary means to detect conditions conducive to ice accretion on aircraft critical surfaces. To help relieve flight crew workload and improve aircraft safety, various ice detection systems have been developed. Some ice detection systems have been successfully certified as the primary means of detecting ice, negating the need for the flight crew to actively monitor for icing conditions. To achieve certification as a Primary ice detection system requires detailed substantiation of ice detector performance over the full range of icing conditions and aircraft flight conditions. Some notable events in the aviation industry have highlighted certain areas of the icing envelope that require special attention.

Structural optimization and automation have gained a significant mileage in recent past due to advent of advancements in Computer Aided Design (CAD) and Engineering tools. The conventional approach of design cycle often results in bulkier products requiring optimization activity as a dedicated task resulting in increased overall design time. This paper discusses knowledge based integrated parametric product design philosophy which is a synergistic approach inclusive of all the functions such as design, performance, stress, manufacturing, and automation to produce optimized designs meeting all the functional requirements at preliminary design stage of the product cycle itself. This involves establishing a basic standard architecture for a product family under consideration based on legacy knowledge reflecting the Design Failure Mode Effects Analysis (DFMEA), Design for Manufacturing & Assembly (DFMA) and data driven standard works.

This paper provides an overview of the state-of-art multiscale “Icing Simulation Framework” capability developed at Raytheon Technologies Research Center. Specifically, the application of this framework to simulate droplet runback and runback icing will be presented. In summary, this high-fidelity framework tracks the physical mechanisms associated with droplet dynamics, ice nucleation, growth and interaction with the environment (e.g. adhesion, crystal growth, evaporation, sublimation, etc.) across all relevant scales (including nucleation at <10-7m to ~10-6m of coating/environment interaction to 10-2m of the component) which allows a rigorous investigation of how different environmental (e.g. LWC, MVD, pressure, velocity and temperature) and substrate (e.g. coating molecular and macroscopic specifications) characteristics affect the icing behavior.

Avionics systems are currently undergoing a transition from single core processor architectures to multi-core processor architectures. This transition enables significant advantages in reduction in size, weight, power (SWaP) and cost. However, avionics hardware and software certification policies and guidance are evolving as research and experience is gained with multi-core processor architectures. The unique challenges of using multi-core processors in certified avionics will be discussed. The requirements for a virtualization platform supporting multiple real-time operating system (RTOS) partitions on a multi-core processor used in safety-critical avionics systems are defined, including the ability to support multiple design assurance levels (DAL) on multiple cores, fault isolation and containment, static configuration as per ARINC 653, role-based development as per DO-297, and robust partitioning to reduce cost of incremental certification.

Effective contrail management while ensuring operational and economic efficiencies for flight services is essential for providing services with minimal adverse environmental impact. The paper explores various aspects of contrail management applicable to different platforms such as Unmanned vehicles, Commercial airliners and Business & regional jets. The aspects unique to each platform such as flight levels of operation, fuel types, flight endurance and radius of operation have been analyzed. Expanse of 5G network is resulting in increased flight activity at flight levels not envisaged hitherto. The paper also dwells on the ramifications of the increased proliferation of different platforms at newer flight levels from the perspective of contrail management.

Electric aircraft have emerged as a promising solution for sustainable aviation, aiming to reduce greenhouse gas emissions and noise pollution. Efficiently estimating and optimizing energy consumption in these aircraft is crucial for enhancing their design, operation, and overall performance. This paper presents a novel framework for analyzing and modeling energy consumption patterns in lightweight electric aircraft. A mathematical model is developed, encompassing key factors such as aircraft weight, velocity, wing area, air density, coefficient of drag, and battery efficiency. This model estimates the total energy consumption during steady-level flight, considering the power requirements for propulsion, electrical systems, and auxiliary loads. The model serves as the foundation for analyzing energy consumption patterns and optimizing the performance of lightweight electric aircraft.

The purpose of this paper to is to review the methodology applied by Collins Aerospace to develop, test and qualify a more robust surface ply rubber compound that has demonstrable improvements in durability and performance at sub-freezing temperatures. Using in-service products as a reference, pneumatic deicers in use on regional turboprop applications were selected as a basis for operational characteristics and observed failure modes. Custom test campaigns were developed by Collins to comparatively evaluate key characteristics of the surface ply material including low temperature elasticity, erosion durability, and fluid susceptibility. Collins’ proprietary engineered rubber formulations were individually evaluated and built into fully functional test deicers for component level testing to DO-160G environmental exposure, comparative ice shed performance in Collins’ Icing Wind Tunnel and erosion in Collins’ Rain Erosion Silo.

The aircraft lifecycle involves thousands of transactions and an enormous amount of data being exchanged across the stakeholders in the aircraft ecosystem. This data pertains to various aircraft life cycle stages such as design, manufacturing, certification, operations, maintenance, and disposal of the aircraft. All participants in the aerospace ecosystem want to leverage the data to deliver insight and add value to their customers through existing and new services while protecting their own intellectual property. The exchange of data between stakeholders in the ecosystem is involved and growing exponentially. This necessitates the need for standards on data interoperability to support efficient maintenance, logistics, operations, and design improvements for both commercial and military aircraft ecosystems. A digital thread defines an approach and a system which connects the data flows and represents a holistic view of an asset data across its lifecycle.

Certification standards for high-assurance systems include objectives for demonstrating compliance of process artifacts such as requirements and code with style guidelines and other standards. With the emergence of model-based development, similar objectives have been specified that apply to models. Demonstration of compliance is often achieved by employing a static analysis linter tool. This paper describes Resolint, an open-source, lightweight linter tool for checking compliance of Architecture Analysis and Design Language (AADL) models with modeling guidelines. AADL enables engineers to describe the key elements of distributed, real-time, embedded system architectures with a sufficiently rigorous semantics. In addition, AADL provides an annex mechanism for extending the base language, enabling new kinds of analyses and tool support. Resolint uses the AADL annex capability to provide a language for specifying style guide rule sets.

A typical linear hydraulic actuator would have clearances between the mating components such as Piston-Cylinder arrangement for achieving the functional requirements. It is observed from the vibration tests that the natural frequencies and the responses vary significantly with the excitation levels in these actuators. With increase in the excitation levels natural frequency of the actuators increases, and the damping ratio reduces significantly indicating a nonlinear behavior of the system. Also due to these clearances, jump phenomena and cubic stiffness nonlinearity are identified on the typical hydraulic actuators. The characterization of the clearances and its impact on the vibratory responses is discussed in this paper. Clearances at two interface locations for a typical hydraulic actuator were identified and a Design of Experiments (DOEs) was formulated with different levels of clearances.

Engine oil systems drive and de-aerate air-oil solutions in a two-phase flow to provide an appropriate amount of oil lubrication and cooling. especially in aero-engine and starter-generator component and system. The oil lubrication systems combine three important functions of the Main Oil Pump (MOP) for lubrication and scavenging: the de-aeration and de-oiling of the air-oil mixture generated in the bearing and gearbox sumps and pumping the oil towards the tank. These are critical functions for the aero-engine and starter-generator. An aero-engine lubrication system along with an integrated pump and separation of gas-liquid mixture has been developed and characterized experimentally to increase Collins Aerospace Engine and Control Systems research and development productivity. This system has also improved engine and starter-generator reliability and system performance.