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This document describes guidelines and methods of performing the safety assessment for certification of civil aircraft. It is primarily associated with showing compliance with FAR/JAR 25.1309. The methods outlined here identify a systematic means, but not the only means, to show compliance. A subset of this material may be applicable to non-25.1309 equipment. The concept of Aircraft Level Safety Assessment is introduced and the tools to accomplish this task are outlined. The overall aircraft operating environment is considered. When aircraft derivatives or system changes are certified, the processes described herein are usually applicable only to the new designs or to existing designs that are affected by the changes. In the case of the implementation of existing designs in a new derivation, alternate means such as service experience may be used to show compliance.

This SAE Recommended Practice provides instructions and test procedures for measuring air consumption of air braked vehicles equipped with Antilock Brake Systems (ABS) used on highways.

The following recommendations and suggestions are made for consideration for procurement of new equipment, or modification to existing equipment where practical. Excluded from this AIR is mobile ground equipment, such as fork lift trucks and front end loaders, that have a functional requirement for simultaneous vehicle motion and accessory operation.

This SAE Aerospace Information Report (AIR) enumerates areas of concern which need to be addressed when the aircraft propulsion control system functions are distributed. Distributed items may include electronic control sensors, electrical or hydraulic power sources, computer hardware and software, etc. This report identifies many factors which should be considered to determine the best system architecture for any given application.

This ARP provides general information on the design and installation of threaded fasteners in high strength, high temperature applications. Some of the more common definitions of fastener terminology are also provided.

This SAE Aerospace Recommended Practice (ARP) describes a procedure for determining the insoluble contamination level of the downstream side of filter elements. Results of this procedure represent the particulate released from the tested filter element under the prevailing conditions of the test. The results may be used for comparative evaluation of the effectiveness of various cleaning methods or the cleanliness of elements after cleaning or as received from manufacturers.

This test method describes a procedure for determining the insoluble contamination level of the downstream side of filter elements. Results of this procedure are intended to be used only for evaluation of the effectiveness of various cleaning treatments, or cleanliness of element as received from manufacturers. The data obtained by this procedure do not necessarily indicate, qualitatively or quantitatively, the contamination which may be released by a filter element into a fluid during service use. Because of the wide variety of conditions which may exist in service applications, it is recommended that the user design and conduct his own particular service performance test. (See paragraph 10.1).

The scope of this SAE Recommended Practice is restricted to the testing of jacks supplied as original equipment on passenger cars, light trucks, and vans. To this end, both component suppliers and vehicle manufacturers are guided in the proper design and testing of jacks.

A number of analytical tools have been used, without any significant success, in the machine manufacturing industry to predict performance of machining processes. The overall equipment efficiency numbers realized on the plant floors provide the supporting evidence of a need of considerable improvements and offer an opportunity for the development of methodologies to characterize the machining processes before installation on the plant floor. Mechanical vibrations signature analysis approach has been used to characterize machine components on the plant floor, but in a limited capacity and under idle conditions. However, attempts to establish vibration standards in machining process characterization without exercising machining loads can cause a false sense of security. This paper describes a methodology of characterizing a given machining process by considering the machine structure, tooling and spindle, workpiece fixture, and the part as the major elements of the machining process.

This paper summarizes the design and implementation of a model-based torque control strategy for drilling. During drilling, the torque often increases due to difficulties with chip evacuation from the drill flutes. Excessive torque can accelerate tool wear or cause torsional failure of the drill. To avoid problems associated with excessive torque, closed loop torque control by manipulation of feedrate was pursued. This strategy simultaneously avoids tool breakage and decreases the cycle time compared to conventional practice. There can be significant cost benefits of torque control due to eliminating tool breakage. For example, reductions in scrap, rework, and machine maintenance costs may be realized. Dynamic models were developed for the drive system, sensing system, and drilling process. These models were subsequently used to design a model-based torque control strategy. Experimental results are presented for conventional twist drilling and form tool drilling applications.

Process modeling benefits are well understood: better quality, and minimal scrap, environmental impact, and unplanned maintenance. The cost of implementing and maintaining process models, however, has limited application of model-based process monitoring and control. New technologies have changed this, with adaptive process modeling reducing the cost of developing and maintaining process models, and thus broadening applications. Applications of neural networks and evolutionary programming have demonstrated quantifiable benefits in process performance, maintenance costs, emissions, and scrap rates. Discrete part, and batch and continuous processing applications are presented to illustrate application qualification criteria and typical costs and benefits.

Industrial users of automation control systems have come to realize the significant non-recurring engineering costs involved with proprietary, or non-standardized, automation control languages. Recent requirements call for standards-based languages to be used when designing modern control systems. There is a simultaneous shift towards open modular factory floor computing platforms based on standardized hardware and “Windows”-based development tools. This paper explores the emergence of methods and strategies which allow for hardware independent program execution of automation control projects written in one or all of the IEC1131-3 Standard Programmable Controller languages.