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Given the fast changing market demands, the growing complexity of features, the shorter time to market, and the design/development constraints, the need for efficient and effective verification and validation methods are becoming critical for vehicle manufacturers and suppliers. One such example is fault-tree analysis. While fault-tree analysis is an important hazard analysis/verification activity, the current process of translating design details (e.g., system level and software level) is manual. Current experience indicates that fault tree analysis involves both creative deductive thinking and more mechanical steps, which typically involve instantiating gates and events in fault trees following fixed patterns. Specifically for software fault tree analysis, a number of the development steps typically involve instantiating fixed patterns of gates and events based upon the structure of the code. In this work, we investigate a methodology to translate software programs to fault trees.

The increasing complexity of aerospace products and programs and the growing competitive pressure is facilitating the aggregation of small, medium and large enterprises of certain geographical regions into more integrated and collaborative entities (clusters). Clusters are by their same nature formed by heterogeneous companies, with huge differences not only in size but also for their core competences: such a diversity is a strength of the cluster, but it also increases its complexity. The purpose of this paper is to describe a benchmarking methodology that can be adopted to assess the performances of companies belonging to a cluster from different perspectives: economics and financials, competitive differentiators, specific know how, business strategies, production and logistic effectiveness, quality of core and supporting processes.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

Simulation-based tolerance analysis is the accepted standard for dimensional engineering in aerospace today. Sophisticated 3D model-based tolerance analysis processes enable engineers to measure variation in complex, often large, assembled products quickly and accurately. Best-in-class manufacturers have adopted Quality Intelligence Management tools for collecting and consolidating this measurement data. Their goal is to completely understand dimensional fit characteristics and quality status before commencing the build process. This results in shorter launch cycles, improved process capabilities, reduced scrap and less production downtime. This paper describes how to use simulation-based approaches to correlate the theoretical tolerance analysis results produced during engineering simulations to actual as-built results. This allows engineers to validate or adjust as-designed simulation parameters to more closely align to production process capabilities.

Secure software distribution in aviation context. Presenter David von Oheimb, Siemens AG

This document establishes the minimum criteria for effective training of air carrier and contractor personnel to deice/anti-ice aircraft to ensure the safe operation of aircraft during ground icing conditions. Appendix D specifies guidelines for particular airplane models.

Abstract More than a decade ago, we proposed combined use of direct injection (DI) and jet ignition (JI) to produce high efficiency, high power-density, positive-ignition (PI), lean burn stratified, internal combustion engines (ICEs). Adopting this concept, the latest FIA F1 engines, which are electrically assisted, turbocharged, directly injected, jet ignited, gasoline engines and work lean stratified in a highly boosted environment, have delivered peak power fuel conversion efficiencies well above 46%, with specific power densities more than 340 kW/liter. The concept, further evolved, is here presented for unmanned aerial vehicle (UAV) applications. Results of simulations for a new DI JI ICE with rotary valve, being super-turbocharged and having gasoline or methanol as working fuel, show the opportunity to achieve even larger power densities, up to 430 kW/liter, while delivering a near-constant torque and, consequently, a nearly linear power curve over a wide range of speeds.

Abstract The preliminary gas turbine combustor design process uses a huge amount of empirical correlations to achieve more optimized designs. Combustion efficiency, in relation to the basic dimensions of the combustor, is one of the most critical performance parameters. In this study, semi-empirical correlations for combustion efficiencies are examined and correlation coefficients have been revised using an experimental air-blasted tubular combustor that uses JP8 kerosene aviation fuel. Besides, droplet diameter and effective evaporation constant parameters have been investigated for different operating conditions. In the study, it is observed that increased air velocity significantly improves the atomization process and decreases droplet diameters, while increasing the mass flow rate has a positive effect on the atomization—the relative air velocity in the air-blast atomizer increases and the fuel droplets become finer.

This document explains how industry standard SAE AS5553 supports implementation of DFARS 252-246-7007 using a practical cost effective and risk based approach

Acoustic Microscopy Test Methods for Counterfeit Capacitors

The intent of this document is to define the methodology for suspect/counterfeit parts inspection using REME Analysis. The purpose of REME Analysis for suspect counterfeit part inspection is to detect misrepresentation or tampering of a part. REME Analysis can also potentially detect unintentional damage to the part resulting from improper removal of the part from assemblies, exposure to electrostatic discharge, exposure to radiation outside of acceptable limits (ionizing or high-power electromagnetic), or degradation. Improper removal of part from assemblies may include, but is not limited to, prolonged elevated temperature exposure during desoldering operations or mechanical stresses during removal. Degradation may include, but is not limited to, prolonged burn-in/testing, exposure to out-of-specification environmental conditions, or use outside of expected electrical tolerances.

Non-conformance and now Suspect counterfeit packaging represents a hazard to electrostatic discharge (ESD) sensitive devices or components through cross contamination during transport and storage while generating high voltage discharges to ESD sensitive devices during in shipping, the inspection process, handling and manufacturing. Several aerospace related issues involve long-term storage supplier non-conformance with antistatic foams, antistatic bubble, antistatic pink poly, vacuum formed antistatic polymers, Type I moisture barrier bags and Type III static shielding bags have posed issues. The late John Kolyer, Ph.D. (Boeing, Ret.) and Ray Gompf, P.E., Ph.D. (NASA-KSC, Ret.) were advocates in the utilization of a formalized physical testing material qualification process. Today, however, prime contractors and CMs rely heavily upon a visual inspection process for ESD packaging materials.

This document defines capabilities and limitations of LSM and CLSM as they pertain to suspect/counterfeit EEE part detection. Additionally, this document outlines requirements associated with the application of LSM and CLSM including: operator training, sample preparation, various imaging techniques, data interpretation, calibration, and reporting of test results. This test method is primarily directed to analyses performed in the visible to near infrared range (approximately 400nm to 1100nm). The Test Laboratory shall be accredited to ISO/IEC 17025 to perform the LSM and CLSM Test Methods as defined in this standard. The Test Laboratory shall indicate in the ISO/IEC 17025 Scope statement, the specific method being accredited to: Option 1: All AS6171/17 Test Methods, or Option 2: All AS6171/17 Test Methods except CLSM. If SAE AS6171/17 is invoked in the contract, the base document, AS6171 General Requirements shall also apply.