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In the last two decades, an aerospace industry trend in the secondary power distribution concept has been dominated by power electronics technology which includes power converters and Power Control Modules based on Solid State Power Control (SSPC) switching elements. These Power Control Modules, grouped around microprocessor based controllers and combined in a single electronic chassis, have become a backbone of electrical power distribution systems on all major commercial and military transport aircraft. Due to the resistive properties of the semiconductor-based SSPC devices, whose behaviors can be described as nonlinear functions of ambient operating temperature, power distribution system integration with SSPCs is challenged and heavily affected by operating temperatures and power dissipation limits. Although aircraft compartments where Power Control Modules are located are considered temperature and pressure controlled, high ambient operating temperatures are possible and expected.

Avionics industry is moving towards more electric & lightweight aircrafts. Electromagnetic effects becomes significantly challenging as materials starts moving towards composite type. Traditional methods for controlling EMC will not be sufficient. This shift increases the complexity of in-flight hardware elements for EMI/EMC control. This paper discusses the need for EMI/EMC Control and brings out the analysis & applicability of various EMI/EMC standards in aerospace, commercial and industrial electronic products, provides comparative study with respect to levels. The study include various sections of DO-160 and applicable guidelines for controlling EMI/EMC with respect to LRU (Line Replaceable Unit) & wire/cable harnesses. Also presents guidelines with respect to shielding of components, selection of components, grounding schemes, filter topologies and layout considerations.

The complexity of software development is increasing unprecedentedly with every next generation of aircraft systems. This requires to adopt new techniques of software design and verification that could optimize the time and cost of software development. At the same time these techniques need to ensure high quality of software design and safety compliance to regulatory guidelines like DO-178C [1] and its supplements DO-330[2] and DO-331[3]. To arrive at new technologies one has to evaluate the alternate methods available for software design by developing models, integration of models, auto-code generation, auto test generation and also the performance parameters like time, effort, reuse and presentation needs to be evaluated. We have made an attempt to present summary of alternate design concept study, and edge of MBD over other design techniques.

In aerospace industry, the concept of Integrated Vehicle Health Management (IVHM) has gained momentum and is becoming need of the hour for entire value chain in the industry. The expected benefits of lesser time for maintenance reduced operating cost and ever busy airports are motivating aircraft manufacturers to come up with tools, techniques and technologies to enable advanced diagnostic and prognostic systems in aircrafts. At present, various groups are working on different systems and platforms for health monitoring of an aircraft e.g. SHM (Structural Health Monitoring), PHM (Prognostics Health Monitoring), AHM (Aircraft Health Monitoring), and EHM (Engine Health Monitoring) and so on. However, these approaches are mostly restricted to federated architecture where faults and failures for standalone line replaceable units (LRUs) are logged inside the unit in fault storage area and are retrieved explicitly using maintenance based applications for fault and failure diagnostics.

This paper presents an overview of a project called “Modelling and Simulation Tools for Systems Integration on Aircraft (MISSION)”. This is a collaborative project being developed under the European Union Clean Sky 2 Program, a public-private partnership bringing together aeronautics industrial leaders and public research organizations based in Europe. The provision of integrated modeling, simulation, and optimization tools to effectively support all stages of aircraft design remains a critical challenge in the Aerospace industry. In particular the high level of system integration that is characteristic of new aircraft designs is dramatically increasing the complexity of both design and verification. Simultaneously, the multi-physics interactions between structural, electrical, thermal, and hydraulic components have become more significant as the systems become increasingly interconnected.

Modern aircraft systems employ numerous processors to achieve system functionality. In particular, engine controls and power distribution subsystems rely heavily on software to provide safety-critical functionality, and are expected to move toward multicore architectures. The computing hardware-layer of avionic systems must be able to execute many concurrent workloads under tight deterministic execution guarantees to meet the safety standards. Single-chip multicores are attractive for safety-critical embedded systems due to their lightweight form factor. However, multicores aggressively share hardware resources, leading to interference that in turn creates non-deterministic execution for multiple concurrent workloads. We propose an approach to remove on-chip interference via a set of methods to spatio-temporally partition shared multicore resources.

Avionics industry is moving towards fly-by wire aircrafts with less reliance on mechanical systems leading to increase in the complexity of in-flight hardware elements. RTCA/DO-254 and EUROCAE ED-80 plays a vital role in the design assurance of airborne electronic hardware. RTCA/ DO-254 and EUROCAE ED-80 are the industry standards for Design Assurance Guidance for Airborne Electronic Hardware. The two different agencies FAA and EU regulate and apply this design assurance guidance to the regulatory law in CFR and EASA CS respectively. This paper discusses the need for DO-254 /ED-80 certification in Aerospace industry, the advantages and benefits to the avionics manufacturers. The paper presents the study made on similarities and differences between DO-254/ED-80.

The Aircraft System Health Management (ASHM) tool is a UTC developed web application that provides access to Aircraft Condition Monitoring Function (ACMF) reports and Flight Deck Effects (FDE) records for Boeing 787®, A320®, and A380® aircraft. The tool was built with a flexible architecture to field a range of off-board diagnostics and prognostics modules designed to transform an abundance of data into actionable and timely knowledge about fleet health. This paper describes the system architecture and implementation with a focus on “lessons learned” in applying diagnostic and prognostics algorithms to available fleet data. Key topics include ensuring analytic robustness, design for cross-enterprise collaboration and defining a workable approach to testing, validating and deploying prognostics and diagnostics models with various degrees of complexity. A case study is provided related to fluid leak detection within an environmental control subsystem.

Today's digital avionics systems leverage the use of the Embedded COTS (Commercial Off The Shelf) hardware to fit the need of small form factor, low power, reduced time to market and reduced development time with efficient use of DO-254 for compliance of product. COTS modules are entering in digital avionics systems such as COM (Computer On Module)/SOM (System On Module)/SIP (System In Package) with huge advancement in semiconductor and packaging industry. In today's scenario COTS are very useful for DAL (Development Assurance Level) C and below as the efforts on compliance for DAL A and B are huge. This paper proposes to use these for DAL A and B as well, where one can get enormous benefit on efforts of compliance and time to market. This paper makes an attempt to explain the current scenario of the Embedded COTS usage in Avionics Systems.