This information report provides guidance when the ISO International metric tolerance system for limits and fits per ISO/R286 or ANSI B4.2-1978 is applied on a standard, and also provides a selected series of limits and fits for powerplant construction suitable for holes and shafts up to 500 mm. For holes or shafts over 500 mm or for limits and fits not shown, ISO/R286 should be consulted.
This paper was prepared to support supersession of MIL-S-8879C with Screw Thread Conformity Task Force selected industry standard AS8879C, published by the Society of Automotive Engineers (SAE). Other documentation changes will be covered by separate papers. Separate papers are anticipated for thread gaging issues, and thread gage calibration procedures. The STC-TF decided that the thread design standard needed to be completed before thread gage definition could be addressed. Thread gage definition has to be known before calibration procedures can be addressed.
This SAE Aerospace Information Report (AIR) records the results of an investigation of a dual rotation propeller shaft standard for an engine supplied bearing and the reason for deciding that such a bearing is impracticable.
The objective of this work was to develop a relatively simple screening or bench test, or a combination of such tests, which would evaluate aircraft greases in respect to corrosion protection under the operating conditions described above.
This document addresses measurement uncertainty and consumer risk as they relate to AS8879 thread inspection. It describes the rationale, theory and methodology used to generate the technical content of the AS5870. The document describes how to calculate measurement consumer risk. It documents all of the calculation methods which industry employs today to calculate what is commonly called measurement uncertainty (Appendices A, B, C, D, E and F). These, in turn, are used to calculate measurement uncertainty ratios which are required inputs to calculate measurement consumer risk. Users of this document can apply the information described herein for the evaluation of the capability of their measurements based on the measurement consumer risk. It involves the analysis of the measurement (product) distribution and biases of both the product and measurement system distributions. It protects the consumer from the worst case distribution results.
Data are related to the dimensional changes with respect to room temperature and provide accuracy sufficient for use with most aerospace systems. Two basic methods of solution are presented with examples for steady state conditions involving uniform and non-uniform temperature distributions. The answers to the example problems are carried to the fifth place for a comparison of the results between methods I and II.
The objective of this investigation was to develop a test method for measuring the resistance to rotation of a ball bearing, caused by the grease in that bearing, as a function of temperature. Low temperatures were of particular interest, and it was desired that the test results be expressed in terms which could be used in mechanism design by proper correction for bearing size, etc. It was also desired that the method be capable of measuring 'break away' as well as the running torque of a bearing filled with grease.
The purpose of this information report is to summarize and document data regarding possible alternatives to the use of cadmium plating on hardware typical of the aerospace hose and fitting industry. To document and provide access to information obtained by an industry survey.
Certain techniques involved in determining the dirt or abrasive content of aircraft greases are considered inadequate. It is desirable to develop a method of analysis which will definitely identify the quantity, size, and degree of abrasiveness of foreign substances in lubricating greases.