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This work has for objective to structure a software applied the analysis of the reliability of mechanical components. Starting from the results of tests of failures, or temporary experiments, the program calculates the reliability functions, starting from different statistical distributions. Such distributions are appropriate for different analysis types. A more complete study was made for the Distribution of Weibull, that is the classic model for reliability analysis. The statistical theory is involved in this analysis. Graphic exits that allow a better visualization and understanding of the project conditions are presented together with the reliability functions. This work turns more accessible the concepts related to the theory of the reliability of components and systems, facilitating larger understanding and familiarity.

The analysis of critical speeds of elastic shafts considering gyroscopic effect is performed by the transfer matrix method. A transfer matrix is formulated for free vibration without damping and forced vibrations with damping. A rotor-motor-pump model is analized with both the Finite Element Method (FEM) and Transfer Matrix Method (TMM) to compare and validate the approach. The gyroscopic effect influences in the resonance frequency is analysed.

A computer aided test system, which is called MOde Survey System (MOSS), is newly developed to evaluate a driving pattern and traffic flow in Seoul, Korea. This system is designed for the people who work on vehicle emissions and energy more quantitatively with the aim of being cost-effective and easy-to-use. Compared to currently-existing Test and Measurement Systems, MOSS is designed and developed for a specific goal with a couple of unique features. These features are: 1) To be able to be used as either a stand alone system like a data logging system or a real-time processing system with a PC to easily visualize vehicle performances and traffic information during the test. 2) To provide a statistical analysis program for easy use to analyze of driving pattern and traffic situation with logged test data files.

This paper describes the applicability of the active noise control concept with the objective of evaluating its potentialities in automotive applications. A control system, using adaptative algorithms is proposed to attenuate the generated noise of one sound source. At the end, the simulation results of the system performance in the control of the noise generated by a truck diesel engine will be presented.

This paper presents in a chronological way the main parameters used for automotive vehicles concerning acoustic qualification/quantification. We start with the loudness concept, pass by the “A” weighting philosophy and arrive to the sound level reduction including sound quality. We are able to show a lot of parameters, each one trying to match better the correlation between objective results and subjective evaluations. We mention several aspects regarding the human ear that make difficult the description of sound sensations through a single parameter. We emphasize also the absence of the exposure time in the parameters used to evaluate acoustic comfort. It is shown the large gap between the parameters used in lab and those applied in the legislations through some standards. Some conclusions are presented and the future related to acoustic parameters are discussed.

The main objective of this work is the analysis of the reliability of mechanical components, as well as its application in failure tests commonly used in the practice, in this case, tests for obtaining and verification of the natural frequency associated to the first vibrational mode of turbocharger blades. Of the statistical theory applied to tests of components, it was made a rising of the types of used tests and its application with respect to the sampling of the population in study. Soon after, an analysis is proceeded on correlation and regression of the obtained data of the tests and of the adjustment of curves. Experimental tests were accomplished in the bank of tests of Schwitzer in two different models of turbocharger, and mensured the natural frequencies in a certain number of samples, all of them with the same number of blades..

The purpose of this article is to present the reasons which justify the electromagnetic compatibility (EMC) evaluations used for automotive vehicles. It shows practical experiences of field measurements. Current actions in Brazil to prevent future problems are presented.

This is a report on a further phase of the work undertaken by PETROBRAS and General Motors do Basil in order to develop a test procedure to evaluate lubricant oils taking into account conditions peculiar to Brazil. In a previous phase, the procedure designated as PROBOL IB was outlined. It's starting point was the VE Sequence of the American Society for Testing and Materials (ASTM) and it used as test fuel a mixture of gasoline and 22% of anhydrous ethanol, which is the engine fuel usually marketed in the country. In this present phase, a correlation was attained between results from PROBOL IB and the VE Sequence, using the reference oils utilized by ASTM accredited laboratories for calibration and determining severity on test benches. It was also concluded that the PROBOL IB procedure presents a good repeatability and is less severe than the VE Sequence.

This paper will discuss the problems faced by air carriers in maintaining control of the processes and quality of aircraft maintenance at certified repair stations. Discussed will be the FAA's oversight of repair stations. Also discussed is the need to differentiate levels of oversight between air carrier based repair stations, original equipment manufacture's repair stations and third party repair stations. Data used will include government documents, reports and studies. First hand accounts through interviews of individuals who have been involved with maintenance and the controlling of the processes and quality of aircraft maintenance at third party certified repair stations are also used.

Conformal coatings are used to protect electronic circuitry from environmental conditions such as dust and moisture, that will interfere with the proper operation of Avionics equipment. This paper reveals the limitations of coatings ability to perform this task. Difficulties with selecting the proper type of coating, application processes, integrity testing, durability, and detecting coating failures in the field are discussed. Because of undetected coating failures an increase in the number of No-Fault-Found units will occur. The FAA Accident Investigation Office has issued a safety recommendation letter based on information contained in this paper.

The exponential growth of the airline industry has placed a renewed exigency on identifying ways to cultivate work cultures in which safety permeates all levels and error control is manifested in the actions of all employees throughout their dailey work effort. Promoted by many industry leaders and safety experts as “safety cultures”, these work cultures have at their core a central and pervasive focus on error management and the promotion of safety at all levels within all types of operations. While the concept is endorsed by many, there remains a generalized state of confusion on what exactly a safety culture is, how it may be developed in a specific company, and whether or not it is attainable within the context of the aviation workplace. This paper reviews what experts suggest are the necessary attributes of a safety culture and what it must have as well as what it must become in order to be effective at fostering safety at all levels.

Regardless of whether aircraft maintenance and repair is performed in-house or out-sourced, nondestructive testing (NDT) is a highly important element. Through centralized qualification and certification of NDT personnel, greater assurance can be placed on the outcome of NDT performed in support of those processes. Enhanced safety and reliability of operational aircraft can result from assurances that a standardized level of competency has been achieved by the NDT practitioners involved. The ASNT Central Certification Program (ACCP) is a standardized, comprehensive, and flexible approach to centralized qualification and certification of NDT Level II and Level III personnel. General examinations in five Methods of NDT have been administered. Within ACCP, there are provisions for specific industrial sectors, such as Aircraft Maintenance and Repair, to organize and establish the NDT personnel qualification requirements unique or common to the industrial sector.

This paper examines the development of the split mandrel coldworking process. The process is an improvement of the established split sleeve method. While the split sleeve process made coldworking easy and cost-effective for the first time, the advanced split mandrel process is simpler, quicker, less expensive, and adaptable to applications unsuited for the split sleeve process. Military applications of the split mandrel process are discussed and an application case study is presented as an example.

Microradiographical and ultrasonic methods for the determination of pitting corrosion depth is discussed. Fatigue crack initiation and growth from artificial pits of different depths is studied experimentally. The experime-ntal results were analyzed using fracture mechanics models including those for small cracks. The model shows very good agreement with experiment in describ-ing the initiation and growth of a crack emanating from a pit and in predicting the dependence of the reduction of fatigue life on pit size. Using this analysis, a relation between the depth of the corrosion pit and the fatigue life is established, and thus the prediction of fatigue life of the sample with corrosion pit is related to the radio-graphic and ultrasonic measurements.

A turbulent flame speed model based on the design and operating parameters of a spark ignition engine has been developed. The flame structure model calculates the flame speed from the flame kernel development, where the flame speed is laminar, throughout transition and turbulent flame. The turbulent flame model was calibrated against experiments carried out in an isooctane-fueled research engine running under several different conditions. The parameters varied during the tests were air-fuel ratio, engine rotational speed, ignition timing and compression ratio. Limiting conditions, where knock or incomplete combustion occurs, were also tested.

Due to the growing need of reducing development time of new products and also to evaluate their reliability, a growing trend towards reduction of field tests has been noted. Bench tests, in contrast, are being more widely used because of the reduced time to carry them out, at much lower costs. In the automotive industry this trend has led to great efforts to make these bench tests as truthful as possible in order to increase their reliability. The quantity of simulated parameters is growing and this, or course, requires the collection of an ever increasing quantity of data from signal measurements (acceleration, temperature, pressure, flow, etc.) in experimental vehicles.

This paper provides an insight into how the introduction and implementation of the blending borescope used to perform on-wing blending of compressor blades on Pratt & Whitney (P&W) Engines has resulted in significant savings. It describes the following: Commercial statistics and savings; Military statistics and potential savings; P&W maintenance team; What is on-wing blending; The capabilities of on-wing blending; The contents of a typical blending borescope inspection kit; Test results; Measurement of Foreign Objects Damage (FOD); Installation of the equipment; How to blend FOD; How to measure the repair and observe how the equipment provides precise results; How to polish the repair. Typical commercial cost savings for blending assembled compressors are in the order of $360,000.00 per event, compared with engine teardown cost.

It is common practice throughout the airline industry to promote technicians into leadership or managerial positions after a period of demonstrated proficiency as maintenance professionals. Research by Purdue University strongly suggests, however, that many of these technicians find themselves in a position which imposes the need for knowledge or skills which they do not possess. While these individuals have found excellence in their technical pursuits, most find it difficult to attain excellence in their new positions due to the lack of adequate training and definition of job expectations. There appears to be a generalized assumption across the aviation industry that good technicians have the intrinsic knowledge and skills to become good leaders and managers. Experience has proven, however, that this is an unrealistic expectation. Research has shown that many of these technicians are confused about the true nature of their job and expectations concerning their performance.

The automobile is one of the main means of transportation in urban areas and it is responsible for a large amount of environmental impacts. Much has been talked about the consequences brought by the automobile during its life time. In this study, it is evaluated the consumption of the energy during the life cycle of the material in an automobile considering the materials extraction, the products of the parts, the automobile assembling, the use of the automobile and the recycling of materials. The period of time of the use of the automobile is varied as well as the efficiency. The main purpose of developing this study is to analyse the importance of the stage of the use of the automobile in the whole life cycle of the material in terms of energy requirements. The results show the energy consumption for the different efficiencies and automobile exchanges. It is interesting to notice that the augmentation of the life of the automobile from nowadays average (150.000 km) brings advantages.

The main topic in this report is the discussion of the advantages of using software that is easy and intuitive for operational planning and dispatch of regional transport aircraft.