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2014-11-11
Technical Paper
2014-32-0111
Brian Mason, Keith Lawes
Abstract For handheld power tools, a four-stroke engine allows compliance with exhaust emissions regulations although four-stroke engines available tend to have unfavorable power to weight. The requirement for a low cost diecast block compromises valve sizes and port flow. While dynamic valve train limitations restrict maximum engine speeds. The use of a rotary valve as opposed to poppet valves avoids these issues and results in an engine with competitive performance. The engine block can be diecast and the engine can operate up to 14,000 rpm without valve related issues. This paper describes the evolution of a rotary valve concept and its application to two 35cc handheld development engines. The HRCV35 is based on a belt driven rotary valve horizontally mounted parallel to the crankshaft axis. The VRCV35 is based on a gear driven rotary valve vertically mounted on the cylinder axis. In both configurations, the rotary valve exposes inlet and exhaust ports providing unrestricted flow. The valve generates turbulence for easy starting and can operate on low volatility fuels such as aviation kerosene or JP8.
2014-11-11
Technical Paper
2014-32-0009
Alexander Trattner, Helmut Grassberger, Oliver Schoegl, Stephan Schmidt, Roland Kirchberger, Helmut Eichlseder, Armin Kölmel, Stephan Meyer, Tim Gegg
Abstract One of the most significant current discussions worldwide is the anthropogenic climate change accompanying fossil fuel consumption. Sustainable development in all fields of combustion engines is required with the principal objective to enhance efficiency. This certainly concerns the field of hand-held power tools as well. Today, two-stroke SI engines equipped with a carburetor are the most widely used propulsion technology in hand-held power tools like chain saws and grass trimmers. To date, research tended to focus on two-stroke engines with rich mixture setting. In this paper the advantages and challenges of leaner and/or lean operation are discussed. Experimental investigations regarding the influence of equivalence ratio on emissions, fuel consumption and power have been performed. Accompanying 3D-CFD simulations support the experiments in order to gain insight into these complex processes. The investigations concentrate on two different mixture formation processes, i.e. CCI (crankcase injection) and LPDI (low pressure direct injection).
2014-11-11
Technical Paper
2014-32-0036
Jan Czerwinski, Markus Kurzwart, Andreas Mayer, Pierre Comte
Abstract The progressing exhaust gas legislation for on- and off-road vehicles includes gradually the nanoparticle count limits. The invisible nanoparticles from different emission sources penetrate like a gas into the living organisms and may cause several health hazards. The present paper shows some results of a modern chain saw with & without oxidation catalyst, with Alkylate fuel and with different lube oils. The measurements focused specially on particulate emissions. Particulates were analysed by means of gravimetry (PM) and granulometry SMPS (PN). In this way the reduction potentials with application of the best materials (fuel, lube oil, ox-cat.) were indicated. It has been shown that the particle mass (PM) and the particle numbers (PN), which both consisting almost exclusively of unburned lube-oil, can attain quite high values, but can be influenced by the lube oil quality and can be considerably reduced with an oxidation catalyst.
2014-11-07
Book
Ian K. Jennions
Integrated Vehicle Health Management: Implementation and Lessons Learned is the fourth title in the IVHM series published by SAE International. This new book introduces a variety of case studies, lessons learned, and insights on what it really means to develop, implement, or manage an integrated system of systems. Integrated Vehicle Health Management: Implementation and Lessons Learned brings to the reader a wide set of hands-on stories, made possible by the contribution of twenty-three authors, who agreed to share their experience and wisdom on how new technologies are developed and put to work. This effort was again coordinated by Dr. Ian K. Jennions, Director of the IVHM Centre at Cranfield University (UK), and editor of the previous books in the series. Integrated Vehicle Health Management: Implementation and Lessons Learned, with seventeen, fully illustrated chapters, covers diverse areas of expertise such as the impact of trust, human factors, and evidential integrity in system development.
2014-10-13
Technical Paper
2014-01-2589
Chunshan Li, Guoying Chen, Changfu Zong
Abstract The passive fault-tolerant approach for four-wheel independently driven and steered (4WID/4WIS) electric vehicles has been investigated in this study. An adaptive control based passive fault-tolerant controller is designed to improve vehicle safety, performance and maneuverability when an actuator fault happens. The proposed fault tolerant control method consists of the following three parts: 1) a fault detection and diagnosis (FDD) module that monitors vehicle driving condition, detects and diagnoses actuator failures with the inequality constraints; 2) a motion controller that computes the generalized forces/moments to track the desired vehicle motion using Model Predictive Control (MPC); 3) a reconfigurable control allocator that redistributes the generalized forces/moments to four wheels with equality constrained optimization. The FTC approach is based on the reconfigurable control allocation which reallocates the generalized forces/moments among healthy actuators once the actuator failures is detected.
2014-10-08
Standard
AIR6226
Most of the Trimmable Horizontal Stabilizer Actuators (THSA) feature a dual structural load path, the primary load path being loaded, the secondary load path being normally unloaded, or both load paths sharing in parallel the Horizontal Stabilizer load. This document describes existing methods for detecting rupture or disconnection of loaded load paths as an overview for those specifying or designing Horizontal Stabilizer Trim Actuators in order to compare existing solutions as reference for implementation in new aircraft programs.
2014-10-06
WIP Standard
AS955A
This SAE Aerospace Standard (AS) covers high strength thin wall (commercial) metric sockets, universal metric sockets, metric box wrenches and metric torque adaptors which possess the strength, clearances, and internal wrenching design so configured that, when mated with 12 point fasteners conforming to the requirement of ISO 4095, they shall transmit torque to the fastener without bearing on the outer 5% of the fastener's wrenching points. This standard provides additional requirements beyond ASME B107.100 and B107.5M appropriate for aerospace use. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes. The dimensional limits of box and combination wrench lengths have been established to provide configuration control for tool storage applications.
2014-10-06
Standard
ARP1558
This SAE Aerospace Recommended Practice (ARP) discusses damage to aircraft fuselages caused by ground equipment contact at servicing and recommends methods to be incorporated or considered in ground equipment design for protection against that damage.
2014-10-02
WIP Standard
ARP6335
The document will provide industry best practicies to detect, identify and prevent malicious electronic parts and embedded firmware / software for entering the DoD Supply Chain. The best practices will assist the DoD contractors to meet the requirements of DoD D 5000.02, DoD I 5200.39 and DoD I 5200.44 to ensure the integrity and trust of microelectronic components and software being designed and built into DoD systems.
2014-09-30
WIP Standard
AIR6334
This SAE Aerospace Information Report (AIR) examines the need for and the application of a power train usage metric that can be used to more accurately determine the TBO for helicopter transmissions. It provides a formula for the translation of the recorded torque history into mechanical usage. It provides examples of this process and recommends a way forward. This document of the SAE HM-1 IVHM Committee is not intended as a legal document and does not provide detailed implementation steps, but does address general implementation concerns and potential benefits.
2014-09-30
Technical Paper
2014-01-2427
Giorgio Malaguti, Carlo Ferraresi, Luca Dariz, Massimiliano Ruggeri
Abstract Alongside with the increasing vehicle complexity, the functionalities related to the safety, diagnosis and maintainability have become critical. The operators of special machines such as agricultural, mining, construction vehicles might be overwhelmed by this increased complexity and, as a result, operations for the recovery or maintenance of their vehicles become difficult. The Augmented Reality (AR) seems to be a very promising technology both if applied to traditional smart-phones or to the upcoming glasses, that has been just presented to the market by several manufacturers. This paper reviews some use cases of applications created in Institute for Agricultural and Earthmoving Machines (IMAMOTER) of the National research Council of Italy (CNR) engineers laboratories, which propose a novel approach for assisted maintenance, recovery or training. These take advantage of the use of AR, providing an efficient method for user fast learning of simple procedures as well as a support for fault recovery and maintenance in hazardous environments or work places.
2014-09-30
Standard
AIR1673B
Manufacturers/designers of all aircraft equipped with a pallet/container capability have provided a means of linking the ground loaders/elevators with the aircraft sill for the smoother transfer of pallets and containers into or out of the aircraft holds. Use of the aircraft attachment points may be used as a means of averting damage to the aircraft door frames and other important parts. Latch-on guarantees fore and aft and vertical alignment of the loader bed with the aircraft doorway, when used in conjunction with the appropriate ground equipment. This SAE Aerospace Information Report (AIR) has been prepared by SAE Subcommittee AGE-2A to present a review of the current range of aircraft attachment points on wide body aircraft and those narrow body aircraft with a ULD cargo capability. Airline operators, who utilized these facilities, have been faced with a growing number of adaptor bars necessary to suit each type of aircraft and door position. There is also a stowage problem on the elevator compounded by the increasing number of bars necessary to suit each aircraft.
2014-09-30
WIP Standard
AMSSTD2154B
The purpose of this military standard is to provide uniform methods for the ultrasonic inspection of wrought metals and wrought metal products.
2014-09-23
WIP Standard
GEIA859B
Data is information (e.g., concepts, thoughts, and opinions) that have been recorded in a form that is convenient to move or process. Data may represent tables of values of various types (numbers, characters, and so on). Data can also take more complex forms such as engineering drawings and other documents, software, pictures, maps, sound, and animation.

Data management, from the perspective of this standard, consists of the disciplined processes and systems that plan for, acquire, and provide stewardship for product and product-related business data, consistent with requirements, throughout the product and data life cycles. Thus, this standard primarily addresses product data and the business data required for collaboration from the team level or extended through the trading partner level during product acquisition and sustainment. It is recognized, however, that the principles described in this standard also have broader application to business data and operational data generally. It is also recognized that the data addressed by this standard is subject to data administration, metadata management, records management, and other processes applied at the enterprise level, and that these principles must be applied in that enterprise context.

2014-09-17
WIP Standard
J2297
This SAE Standard applies to dyes intended to be introduced into a mobile air-conditioning system refrigerant circuit for the purpose of allowing the application of ultraviolet leak detection. In order to label any product(s) they shall meet SAE J2297, and the certification process as described in SAE J2911 must be followed and the documentation described in the appendix shall be submitted to SAE.
2014-09-16
Technical Paper
2014-01-2164
Srikanth Gururajan, Mario Luca Fravolini, Matthew Rhudy, Antonio Moschitta, Marcello Napolitano
Abstract Recent catastrophic air crashes have shown that physical redundancy is not a foolproof option for failures on Air Data Systems (ADS) on an aircraft providing airspeed measurements. Since all the redundant sensors are subjected to the same environmental conditions in flight, a failure on one sensor could occur on the other sensors under certain conditions such as extreme weather; this class of failure is known in the literature as “common mode” failure. In this paper, different approaches to the problem of detection, identification and accommodation of failures on the Air Data System (ADS) of an aircraft are evaluated. This task can be divided into component tasks of equal criticality as Sensor Failure Detection and Identification (SFDI) and Sensor Failure Accommodation (SFA). Data from flight test experiments conducted using the WVU YF-22 unmanned research aircraft are used. Analytical redundancy is provided through a least squares modeling based approach and an extended Kalman filter approach to handle the Sensor Failure Accommodation (SFA) task.
2014-09-16
Technical Paper
2014-01-2132
Prashant Vadgaonkar, Ullas Janardhan, Adishesha Sivaramasastry
Abstract Performance of Avionics systems is dictated by the timely availability and usage of critical health parameters. Various sensors are extensively used to acquire and communicate the desired parameters. In today's scenario, sensors are hardwired. The number of sensors is growing due to automation which increases the accuracy of intended Aircraft functions. Sensors are distributed all over the Aircraft and they are connected through wired network for signal processing and communication. LRUs (Line Replaceable Unit) which are integrating various sensors also use a wired approach for communication. The use of a wired network approach poses challenges in terms of cable routing, stray capacitances, noise, mechanical structure and added weight to the structure. The weight of cables contributes significantly to the overall weight of the aircraft. As the weight of Aircraft increases, the required fuel quantity also increases. The Key driver for Airline operational cost is fuel. Fuel quantity is a direct function of weight.
2014-09-16
Technical Paper
2014-01-2144
Marco Amrhein, Jason Wells, Eric Walters, Seana McNeal, Brett Jordan, Peter Lamm
Abstract Transient operating conditions in electrical systems not only have significant impact on the operating behavior of individual components but indirectly affect system and component reliability and life. Specifically, transient loads can cause additional loss in the electrical conduction path consisting of windings, power electronic devices, distribution wires, etc., particularly when loads introduce high peak vs. average power ratios. The additional loss increases the operating temperatures and thermal cycling in the components, which is known to reduce their life and reliability. Further, mechanical stress caused by dynamic loading, which includes load torque cycling and high peak torque loading, increases material fatigue and thus reduces expected service life, particularly on rotating components (shaft, bearings). This article investigates the aforementioned stress mechanisms and provides analysis techniques and metrics to quantify the impact of transient operating conditions onto system and component reliability and life.
2014-09-16
Technical Paper
2014-01-2161
Alireza R. Behbahani, Alex Von Moll, Robert Zeller, James Ordo
Abstract Modern propulsion system designers face challenges that require that aircraft and engine manufacturers improve performance as well as reduce the life-cycle cost (LCC). These improvements will require a more efficient, more reliable, and more advanced propulsion system. The concept of smart components is built around actively controlling the engine and the aircraft to operate optimally. Usage of smart components intelligently increases efficiency and system safety throughout the flight envelope, all while meeting environmental challenges. This approach requires an integration and optimization, both at the local level and the system level, to reduce cost. Interactions between the various subsystems must be understood through the use of modeling and simulation. This is accomplished by starting with individual subsystem models and combining them into a complete system model. Hierarchical, decentralized control reduces cost and risk by enabling integration and modularity. This process involves defining, developing, and validating against requirements for key integrated propulsion, power, and thermal management system capabilities.
2014-09-05
Standard
AMS1448B
This specification covers natural sand in granular form. This sand has been used typically to improve the frictional properties of runway, taxiway, and ramp surfaces for aircraft braking purposes, but usage is not limited to such applications.
2014-09-05
Standard
ARP5548
This equipment specification covers requirements for Multi-Tasking Equipment (MTE) for airfield snow removal purposes. The unit shall include a combination of a carrier vehicle, snow plow, rotary broom and high velocity air blast system. This vehicle as a unit shall be an integrated snow plow, rotary broom and high velocity air blast. Primary application is for the high-speed plowing, sweeping and cleaning of ice and snow from airfield operational areas such as runways, taxiways and ramp aprons. The term carrier vehicle represents the various self-propelled prime movers that provide the motive power necessary to move snow and ice control equipment during winter operations. The airport operator may require this specified piece of equipment in order to maintain the airfield during large and small snow events. When necessary, the MTE shall be a central and critical element in the winter pavement maintenance fleet in the effort to accomplish the airport’s published snow plan. This ARP defines the minimum functionality for a vehicle to be classified as an MTE, specifically as an integrated snow and ice removal system capable of performing multiple and simultaneous functions requiring no more than one operator.
2014-08-18
WIP Standard
J98
This SAE Standard is intended to be used as a guide for manufacturers and users of general purpose industrial machines to provide a reasonable degree of protection for personnel during normal operation and servicing. This document excludes skid steers which are covered by SAE J1388. Avoidance of accidents also depends upon the care exercised by such persons (see SAE J153). Inclusion of this standard instate, federal, or any laws or regulations where flexibility of revision is lacking is discouraged.
2014-08-11
Standard
J1979_201408
SAE J1979 / ISO 15031-5 set includes the communication between the vehicle's OBD systems and test equipment implemented across vehicles within the scope of the legislated emissions-related OBD.
2014-08-06
WIP Standard
J2970
This standard provides the testing and functional requirements guidance necessary for a leak detection device that uses any non-A/C refrigerant tracer gas, such as helium or a nitrogen-hydrogen blend, to provide functional performance equivalent to a refrigerant electronic leak detector. It explains how a non- refrigerant leak detector’s calibration can be established to provide levels of detection equal to electronic leak detectors that meet SAE J2791 for R-134a and SAE J2913 for R-1234yf.
2014-08-05
Standard
ARP5149BDA
This Digital Annex (DA) contains the current, full-PDF version of ARP5149B, Training Program Guidelines for Deicing/Anti-Icing of Aircraft on Ground, as well as .jpeg format files of Appendix D, Application Guidelines Configuration, Critical Component, and Spray Area Diagrams for Aircraft. The .jpeg diagram files may be used by purchasers in accordance with the terms of the included license agreement.
2014-08-01
WIP Standard
GEIASTD0010A
This document outlines a standard practice for conducting system safety. The system safety practice as defined herein provides a consistent means of evaluating identified risks. Mishap risk must be identified, evaluated, and mitigated to a level as low as reasonably practicable. The mishap risk must be accepted by the appropriate authority and comply with federal (and state, where applicable) laws and regulations, executive orders, treaties, and agreements. Program trade studies associated with mitigating mishap risk must consider total life cycle cost in any decision.

This document is intended for use as one of the elements of project solicitation for complex systems requiring a systematic evaluation of safety hazards and mitigating measures. The Managing authority may identify, in the solicitation and system specification, specific system safety engineering requirements to be met by the Developer. These may include risk assessment and acceptance criteria, unique classifications and certifications, or mishap reduction needs unique to their program.

2014-07-29
Standard
AIR5372A
This SAE Aerospace Information Report (AIR) describes the design approaches used for current applications of aircraft Brake-by-Wire (BBW) control systems. The document also discusses the experience gained during service, and covers system, ergonomic, hardware, and development aspects. The document includes the lessons that have been learned during application of the technology. Although there are a variety of approaches that have been used in the design of BBW systems, the main focus of this document is on the current state of the art systems.
2014-07-24
Standard
J1628_201407
This SAE Recommended Practice applies to the use of generally available leak detection methods to service motor vehicle passenger compartment air conditioning systems.
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