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2015-10-19
WIP Standard
AS6350
Recent Salt-Fog environmental qualification testing in accordance with RTCA/DO-160G, Paragraph 14, Category S identified both discrepancies in the performance specification documents and potential in-service corrosion problems with the charging valve. A new SAE AS for Valve; Aircraft, Pneumatic, High-Pressure Charging is necessary to resolve these items.
2015-10-16
WIP Standard
AS6347
This document applies to the development of Plans for integrating and managing electronic materials and processes in equipment for the military and commercial aerospace markets; as well as other ADHP markets that wish to use this document.
2015-10-14
WIP Standard
ARP4754B
This document discusses the development of aircraft systems taking into account the overall aircraft operating environment and functions. This includes validation of requirements and verification of the design implementation for certification and product assurance. It provides practices for showing compliance with the regulations and serves to assist a company in developing and meeting its own internal standards by considering the guidelines herein.
2015-10-13
WIP Standard
GEIASTD0008A
This Standard specifies the minimum derating requirements for using electronic components in moderately severe environments. These environments are assumed to include Airborne Inhabited Cargo (AIC), Airborne Inhabited Fighter (AIF), Ground Mobile (GM), and Naval Sheltered (NS) environments specified in MIL-HDBK-217. This Standard is intended to supersede the derating limits contained in Defense Standardization Program Office (DSPO) Standardization Directive SD-18, Naval Standard TE000-AB-GTP-010, and Air Force ESD-TR-85-148. It is intended that a future revision of this Standard will include additional requirements for derating for other environments (e.g. Airborne Uninhabited Cargo). Since this Standard specifies the minimum derating requirements, (sub)contractors may derate in excess of these requirements.
2015-10-12
WIP Standard
J1699/3
The main purpose of this Recommended Practice is to verify that vehicles are capable of communicating a minimum subset of information, in accordance with the diagnostic test services specified in SAE J1979: E/E Diagnostic Test Modes, or the equivalent document ISO 15031-5: Communication Between Vehicle and External Equipment for Emissions-Related Diagnostics – Part 5: Emissions-related diagnostic services. Any software meeting these specifications will utilize the vehicle interface that is defined in SAE J2534, Recommended Practice for Pass-Thru Vehicle Programming.
2015-10-04
WIP Standard
AS4775B
This document covers the general requirements for hydraulic aircraft jacks. It can be applied to tripod, unipod, and axle jacks that may be used on open ramp areas as well as in the aircraft hanger.
2015-10-01
Journal Article
2015-01-9019
Jean-Baptiste Gallo, Robert L. Russell, Kent Johnson, Thomas Durbin
Abstract With funding from the California Energy Commission, the California Hybrid, Efficient and Advanced Truck Research Center, contracted with the University of California, Riverside's College of Engineering to evaluate the performance of a Class 5 battery electric urban delivery vehicle over two standardized driving cycles and a steady state range test on a chassis dynamometer. The test vehicle, a Smith Electric Newton Step Van, was equipped with a proprietary data acquisition system which was set to record a wide variety of vehicle parameters at a 1 Hz sampling period. In addition, the chassis dynamometer was set to measure and record additional parameters. Lastly, a portable J1772 EVSE recorded both grid energy and power at 15-minute intervals. This project provides a controlled test evaluation of the Smith Electric Newton Step Van.
2015-09-29
Technical Paper
2015-01-2728
Paul C. Cain
Abstract OEM benefit: Vehicle manufacturers desire continuous feedback in monitoring key safety related sub-assemblies. In this application, engineers are calculating the remaining brake pad life by continuously monitoring the current thickness of the brake pad friction material. This information is used in scheduling preventative maintenance activities and avoiding safety incidents. Unplanned machine down time and field repair expenses in earthmoving equipment are cost prohibitive. Today, this technology allows OEM's to have high confidence, continuous feedback on this critical vehicle safety feature, avoiding expensive, unplanned repairs and to improve field “up time” performance. Application challenge: to develop a reliable linear position sensor that is suitable for continuous monitoring of brake pad material thickness in a high pressure, high temperature, high vibration and contaminated environment typical of large construction (earthmoving) vehicles.
2015-09-29
WIP Standard
ARP6348
This document provides additional guidance on performing lifetime assessments and mitigations for ARP6338. It is intended for use by designers, reliability engineers, and others associated with the design, production, and support of electronic sub-assemblies, assemblies, and equipment used in ADHP applications.
2015-09-29
Technical Paper
2015-01-2879
Evandro Silva
Abstract In recent years the commercial vehicle industry, specifically the heavy duty truck product line, has seen a rapid increase in the replacement of pure mechanical systems by electronic controlled systems. Engine, transmission, brakes, lighting, clusters, etc. are all monitored and/or controlled electronically. The adoption of electronic systems created a substantial change in the complexity of the heavy duty trucks systems. Currently Diagnostic Trouble Codes (DTC) displayed on instrument clusters, in the majority of the cases, are no longer generated by a single sensor/component failure, instead these DTCs are triggered by a system monitor flag, as the result of a below average performance or a failure of an entire system. This new level of complexity makes it very difficult for the current diagnostic methods and tools, to identify what is causing the equipment to operate below ideal conditions.
2015-09-29
Journal Article
2015-01-2846
Chunshan Li, Guoying Chen, Changfu Zong, Wenchao Liu
Abstract This paper presents a fault-tolerant control (FTC) algorithm for four-wheel independently driven and steered (4WID/4WIS) electric vehicle. The Extended Kalman Filter (EKF) algorithm is utilized in the fault detection (FD) module so as to estimate the in-wheel motor parameters, which could detect parameter variations caused by in-wheel motor fault. A motion controller based on sliding mode control (SMC) is able to compute the generalized forces/moments to follow the desired vehicle motion. By considering the tire adhesive limits, a reconfigurable control allocator optimally distributes the generalized forces/moments among healthy actuators so as to minimize the tire workloads once the actuator fault is detected. An actuator controller calculates the driving torques of the in-wheel motors and steering angles of the wheels in order to finally achieve the distributed tire forces. If one or more in-wheel motors lose efficacy, the FD module diagnoses the actuator failures first.
2015-09-28
WIP Standard
TB0003A
This Technical Bulletin covers the following areas of concern. Prevention: Actions recommended for procuring parts and materials with a full warranty; Actions recommended for minimizing risks and protecting your Program from counterfeiting; Actions recommended when buying from a non-authorized supplier. Detection: Actions recommended when procuring parts from an unauthorized supplier or otherwise suspect that a part or material at risk of being counterfeit has been procured. Risk Mitigation: Actions recommended when no reasonable alternatives exist (e.g., a redesign is required, an unacceptable schedule delay will result, the program or customer cannot bear the additional cost) and the decision has been made to procure from a non-authorized supplier.
2015-09-25
Standard
AIR5320A
This SAE Aerospace Information Report (AIR) contains information on most of the major icing simulation ground facilities. An effort was made to obtain data from as many facilities as possible over a two year time period. The data in this document represents the state of the facilities in calendar year 1996. Facilities are constantly changing and upgrading and, therefore, some facility specifications may change during the life of this report. Of the 27 facilities described in this report, the primary use is split with approximately half for engine testing and half for wind tunnel testing. The facilities are limited to ground facilities and, therefore, icing tankers have not been included.
2015-09-22
Technical Paper
2015-36-0281
Marcelo Vandresen, James Silveira, Milton Pereira, Richard Chaplin, Gustavo Fernandes
Abstract Integrated controls for commercial dynamometers do not have appropriate characteristics to perform research and teaching tasks. These are developed to perform quick tests and its logic is prepared to obtaining the information in accordance with the technical standards. This way, the use for research is hindered because it does not have an interface that allows a refinement to the desired data ranges, t data sampling and the type of load that is applied. Its use for teaching is limited because these "standard" controls does not allow to analyze or to determine engines characteristics that are not covered through tests specified by the standards, so the use of this tool as an important part in professional training formed by the institution.
2015-09-22
WIP Standard
EIA632A
This Standard is intended to enable an enterprise to strengthen its competitiveness in global markets by engineering and producing quality systems, and by delivering its products on time at an affordable price or cost. The focus, therefore, is on conceptualizing, creating and realizing a system and the products that make up a system. This Standards was developed as a joint project of the Electronic Industries Alliance (EIA) and the International Counci on Systems Engineering (INCOSE). This effort was chartered by the G-47 Systems Engineering Committee of EIA and has been designed as Project PN-3537. this Standard has been approved by the EIA Engineering Department Executive Committee.
2015-09-17
WIP Standard
J3110
This SAE standard applies to any and all Flushing Methods intended for use to internally clean, decontaminate, and recondition components and sections of the refrigerant circuit within a vehicle air conditioning system. This standard provides testing and acceptance criteria for determining the minimum performance of a Flushing Method, intended for use in the servicing and repair process of vehicle air conditioning system. This standard will only specify the Flushing Method performance criteria. Specifications for air conditioning Flushing Fluids are outlined in SAE J3091.
2015-09-16
Collection
This collection of technical papers addesses health management - subsystems; IVHM business case; health monitoring - structures; vehicle level health management; and prognostics and diagnostics.
2015-09-15
Technical Paper
2015-01-2401
Michael Schmidt, Philipp Nguyen, Mirko Hornung
Abstract The projected uptick in world passenger traffic challenges the involved stakeholders to optimise the current aviation system and to find new solutions being able to cope with this trend. Since especially large hub airports are congested, operate at their capacity limit and further extensions are difficult to realise. Delays due to late arrival of aircraft or less predictable ground operation processes disrupt the airport operations in a serious way. Various concepts improving the current turnaround processes have been presented thus far, whereby radical aircraft design changes have little chances for realisation in the short term. By maintaining the established overall aircraft configuration, the concepts promote higher probability to become commercially available for aircraft manufactures and operators.
2015-09-15
Technical Paper
2015-01-2473
Alessandro Ceruti, Alfredo Liverani, Piergiovanni Marzocca
Abstract Traditional User/Maintenance Manuals provide useful information when dealing with simple machines. However, when dealing with complex systems of systems and highly miniaturized technologies, like UAVs, or with machines with millions of parts, a commercial aircraft is a case in point, new technologies taking advantage of Augmented Reality can rapidly and effectively support the maintenance operations. This paper presents a User/Maintenance Manual based on Augmented Reality to help the operator in the detection of parts and in the sequence to be followed to assemble/disassemble systems and subsystems. The proposed system includes a handheld device and/or an head mounted display or special goggles, to be used by on-site operators, with software management providing data fusion and overlaying traditional 2D user/maintenance manual information with an augmented reality software and appropriate interface.
2015-09-15
Technical Paper
2015-01-2486
Greg Kilchenstein, F. Matthew Juarez
Abstract The USAF T56 engine Program Office has adopted a unique maintenance approach which utilizes the concept of complete system reliability in order to optimize their cost of workscoping aircraft gas turbine engines. While classical Reliability Centered Maintenance (RCM) focuses on the actual reliability and failure modes representative of a particular system, its benefits are limited since it only describes individual system components9. The workscope cost optimization program provides the user with recommended optimal repair workscopes based on the underlying reliability and cost of repair options. This maintenance concept is based upon the methodology documented in SAE Aerospace Recommended Practice (ARP) JA6097, which is a “Best Practices Guide” established to provide direction in objectively determining which other maintenance to perform on a system when that system requires corrective action, with the goal of improving overall system reliability at the lowest possible cost.
2015-09-15
Technical Paper
2015-01-2584
Andrew Dickerson, Ravi Rajamani, Mike Boost, John Jackson
Abstract A high fidelity system for estimating the remaining useful life (RUL) for Li-ion batteries for aerospace applications is presented. The system employs particle filtering coupled with outlier detection to predict RUL. Calculations of RUL are based on autonomous measurements of the battery state-of-health by onboard electronics. Predictions for RUL are fed into a maintenance advisor which allows operators to more effectively plan battery removal. The RUL algorithm has been exercised under stressful conditions to assert robustness.
2015-09-15
Technical Paper
2015-01-2583
James Hare, Shalabh Gupta, Nayeff Najjar, Paul D'Orlando, Rhonda Walthall
Abstract This paper addresses the issues of Fault Detection and Isolation (FDI) in complex networked systems such as the Environmental Control System (ECS) of an aircraft. The ECS controls and supplies pressurized air to the aircraft and consists of multiple subsystems that in turn consist of interconnected components, heterogeneous sensing devices, and feedback controllers. These complex interconnections and feedback control loops make fault detection and isolation a very challenging task in the ECS. For example, a faulty component yields off-nominal outputs which are inputs to the other coupled components. This coupling leads to off-nominal outputs from otherwise healthy components, thus causing unwanted false-alarms. Secondly, due to off-nominal inputs, the healthy components are driven beyond their normal operating conditions, leading to cascading failures.
2015-09-15
Technical Paper
2015-01-2585
Tuur Benoit, Yves Lemmens, Wim Desmet PhD
Abstract This paper proposes a solution for utilizing multi-body models in nonlinear state observers, to directly estimate the loads acting on the aircraft structure from measurement data of sensors that are commonly available on modern aircraft, such as accelerometers on the wing, rate gyros and strain gages. A high-fidelity aeroelastic multi-body model of a fixed-wing large passenger aircraft is presented, suitable for the monitoring of landing maneuvers. The model contains a modally reduced flexible airframe and aerodynamic forces modeled with a doublet-lattice method. In addition, detailed multi-body models of the nose and main landing gear are attached to the flexible structure, allowing to accurately capture the loads during a hard landing event. It is expected that this approach will make way for embedding non-linear multi-body models, with a high number of degrees of freedom, in state estimation algorithms, and hence improve health monitoring applications.
2015-09-15
Technical Paper
2015-01-2582
Andre Silva, Nayeff Najjar, Shalabh Gupta, Paul D'Orlando, Rhonda Walthall
Abstract The Environmental Control System (ECS) of an aircraft provides thermal and pressure control of the engine bleed air for comfort of the crew members and passengers onboard. For safe and reliable operation of the ECS under complex operating environments, it is critical to detect and diagnose performance degradations in the system during early phases of fault evolution. One of the critical components of the ECS is the heat exchanger, which ensures proper cooling of the engine bleed air. This paper presents a wavelet-based fouling diagnosis approach for the heat exchanger.
2015-09-15
Technical Paper
2015-01-2589
Julien Feau, Philippe Chantal, Jayant Sen Gupta
Abstract Modern aircraft, such as A380 or A350 for Airbus, are very well connected in flight to ground stations through wireless communications. For maintenance and operations purpose, the aircraft is programmed to send regularly information such as flight reports based on the BITE messages (Built-In Test Equipment) or standard reports based on the value of physical parameters. Moreover, Airbus is capable of sending requests (called uplinks) to the aircraft to retrieve the value of different parameters in almost real-time. This ability, associated with adequate process, improves significantly the reaction time of the diagnostic and prognostic solutions that Airbus can provide to its customers. Traditionally Health Monitoring is considered useful when the Potential to Functional failure (P-F) interval is greater than one flight cycle.
2015-09-15
Technical Paper
2015-01-2592
Joao Pedro Malere, Wlamir Olivares Loesch Vianna
Abstract This paper presents a method to determine the root cause of an aircraft component failure by means of the aircraft fault messages history. The k-Nearest Neighbors (k-NN) and the Tree-Augmented naive Bayes (TAN) methods were used in order to classify the failure causes as a function of the fault messages (predictors). The contribution of this work is to show how well the fault messages of aircraft systems can classify specific components failure modes. The training set contained the messages history from a fleet and the root causes of a butterfly valve reported by the maintenance stations. A cross-validation was performed in order to check the loss function value and to compare both methods performance. It is possible to see that the use of just fault messages for the valve failure classification provides results that close to 2/3 and could be used for faster troubleshooting procedures.
2015-09-15
Technical Paper
2015-01-2590
Yufei Lin, Zakwan Skaf, Ian Jennions
Abstract In the past few decades the number of airplanes has increased dramatically and aircraft systems have become increasingly more complex. Under these conditions, the next generation of airplanes will undergo substantial changes and will make significant technical progress to improve operational safety. This vision is entirely consistent with the adoption of Integrated Vehicle Health Management (IVHM) technology which uses merging of interdisciplinary trends to carry out safe and effective vehicle operation. Hitherto, IVHM has made much progress in the realm of maintenance and operation, but little on safety assessment. This paper discusses the issues around how IVHM could be used to aid the operational safety assessment in the aviation industry. Special attention is paid to existing safety assessment methods, and some challenges and promising research directions are highlighted.
2015-09-15
Technical Paper
2015-01-2619
Karl-Otto Strömberg, Stefan Borgenvall, Mohamed Loukil, Bertrand Noharet, Carola Sterner, Magnus Lindblom, Orjan Festin
Abstract Lightweight Production Technology (LWPT) is today a well-established technology in the automotive industry. By introducing light weight fixtures manufactured from Carbon Fiber Reinforced Plastics (CFRP) in aeronautical applications, new challenges as well as possibilities of in-situ health monitoring emerges. The present paper present results from experimental investigations using optical fibers with multiplex Bragg gratings (FBG) as strain gauges in an industrial CFRP fixture. Fixtures were manufactured of laminates made from CFRP. Measurements have been performed on a single CFRP beam with dimensions (8000 × 500 × 500 mm), used as a structural part in a larger assembly (9000 × 4000mm). The optical fibers were placed in between two laminates on two sides of the beam. The measurement data from the FBGs were compared and correlated to the measured displacements of the beam and the applied loads.
2015-09-15
Technical Paper
2015-01-2555
Ephraim Suhir, Alain Bensoussan, Johann Nicolics
There is a concern that the continuing trend on miniaturization (Moore's law) in IC design and fabrication might have a negative impact on the device reliability. To understand and to possibly quantify the physics underlying this concern and phenomenon, it is natural to proceed from the experimental bathtub curve (BTC) - reliability “passport” of the device. This curve reflects the combined effect of two major irreversible governing processes: statistics-related mass-production process that results in a decreasing failure rate with time, and reliability-physics-related degradation (aging) process that leads to an increasing failure rate. It is the latter process that is of major concern of a device designer and manufacturer. The statistical process can be evaluated theoretically, using a rather simple predictive model.
2015-09-15
Technical Paper
2015-01-2587
Matthew Smith, Peter F. Sulcs, Rhonda Walthall, Mark Mosher, Gregory Kacprzynski
Abstract 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.
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