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This presentation discusses the many rewards of establishing safety as a major criteria in selecting and managing the outside firms that perform aircraft maintenance and repair operations under contract. Whether the outsourced work is done on-site or at the contractor's location, fewer safety incidents among workers can result in better quality work and lower outsourcing costs. To demonstrate a successful program, the presentation reviews DuPont's award-winning approach to contractor safety which has helped the company improve profitability, increase shareholder value and enhance its public image. Six core elements that drive the company's contractor safety program are reviewed.

This paper primarily discusses two non-methylene chloride (and completely non-Hazardous Air Pollutant (non-HAPS)) paint removers. Specific areas discussed include test results, trial results and production results. The two paint removers are Stingray™ 853 and 874B. Stingray™ 876 is also discussed as it compares to 874B.

A study was conducted to develop and validate a Pressurized Water Stripping (PWS) process for use on aircraft and aircraft components to allow selective removal of the topcoat. By design, the process incorporates a barrier coating to encapsulate either the epoxy (MIL-P-23377) or polyurethane (TT-P-2760) primer used on military aircraft today. Then a water-only stripping process is used to remove the MIL-C-85285 polyurethane topcoat leaving the primer and barrier coatings intact. This system includes an inexpensive method for removing and reapplying the topcoat without disturbing the underlying primer or substrate. The barrier coating is designed to be resistant to moisture and erosion damage by the Pressurized Water Stripping process.

The paper describes aircraft maintenance research funded by the Federal Aviation Authority currently being pursued by Clemson University in cooperation with Lockheed Martin Aircraft Center and Delta Air Lines. The research describes how computer based training (for individual skills and team skills) is being used to improve the effectiveness and efficiency of aircraft maintenance operations.

The drive towards improved fuel economy and lower emissions for Diesel vehicles requires the development of catalysts capable of converting not only carbon monoxide (CO) and hydrocarbon (HC), but also particulate matter (PM) and nitrogen oxides (NOx) in a lean exhaust environment. This paper reviews the approaches that are being considered for this purpose, for light duty Diesels, together with factors that may influence catalyst performance such as components in the fuel and quality of the lubricant.

The Closed-Loop, Full Authority Lean Burn Control System provides an high accuracy control strategy made possible by using digital electronics and software technology that overcomes many difficulties encountered in the last few years. Using this technology we will be able to provide significant emissions integrity and protection against detonation caused by changing gas qualities.

A Continuously Variable Cam Phaser (CVCP) used in conjunction with the correct control algorithm can help reduce the negative impact on the environment as well as reduce the energy consumed. Cam phasing has the benefit of improving power and emissions while simultaneously improving fuel economy. This paper will discuss the need for having a good control scheme when using a variable cam phaser and the factors that influence its performance. The paper will outline the factors which affect the cam phaser reaction, and hence the control. The paper will also discuss the importance of using feedback control to properly position the CVCP under dynamic conditions.

The methodology presented in this paper is based in Osborn, who can be condensed as: Men evolve in the measure to which they follow standards, improve standards, and create new standards.... Results through quality, the ultimate objective of performance. The proposed approach is the conjunction of the basic aspects of the HPE (Human Performance Engineering) where all the actions are targeted to the potential contribution and to the ultimate results they can generate. The ISO 9000 (International Standards Organization) standards series is the standard requirement for international and domestic trade. It has been a major catalyst in the universal upgrading of organization quality and operations systems throughout the world.

This paper describes an interactive object-oriented system for damage tolerance design of stiffened panels. Its ultimate goal is to free the engineer from most of the tedious and error prone tasks, so that he can concentrate on the actual design problem and find optimum solutions by experimenting with the design variables in a straightforward, intuitive manner. The panel configuration is represented in an object oriented fashion, using a high level of abstraction and in terms of objects well known to the designer such as: stiffeners, cracks and boundaries. Input data is performed interactively, through a user friendly windows-based interface. Crack propagation analysis is performed with the Boundary Element Method (BEM). The BEM meshes are automatically designed using a knowledge based strategy.

The engine exhaust aftertreatment needs for diesel heavy duty vehicles and passenger cars will be reviewed. A short discussion on current engine based emission reduction technologies will lead to the description of after treatment technologies. The predominant technologies applied are oxidation catalysts for both passenger cars as well as heavy duty trucks and busses. The oxidation catalyst utilizes a large frontal area, flow-through ceramic substrate to remove the SOF, HC, and CO emissions. High efficiency particulate matter removal can be achieved with the use of ceramic diesel particulate filters. The properties and performance data of flow-through substrates as well as particulate traps will be discussed in the paper

As a prelude to the assessment of the global warming impact of automotive air conditioning, fundamental scientific facts about global warming are reviewed. A comprehensive mathematical model is next developed to quantify the total equivalent warming impact (TEWI) of the automotive air conditioning. Using this model, intensive calculations are performed to determine the TEWI of the present R-134a air conditioning system as well as the proposed alternate systems. The calculated results indicate that TEWI of the present R-134a system is higher than those of the flammable subcritical systems (R-152a, R-290 and R-717) but lower than those of the supercritical carbon dioxide system (R-744) and open air (R-729) cycle system. The calculated results show that TEWI of 303 million R-134a automotive air conditioning systems in the worldwide fleet is no more than 0.14% of TEWI of the greenhouse gases emitted annually into Earth's atmosphere due to human activity.

The drive for lower weight instrument panels (IP) can be addressed with different design approaches. The first and more traditional approach is to substitute existing substrate materials with materials having a higher stiffness-to-density ratio. The second approach looks at the sub-system level where weight reduction is achieved through part integration. To exemplify this type of designs, examples of innovative knee bolster solutions are shown. The third and most radical approach is weight reduction at the system level. Alternatives to instrument panels that use traditional cross car beam structures will be presented. With these alternatives, hybrid and structural instrument panels can be developed in which weight reduction is achieved by part integration and by allowing plastic materials to fulfill a more significant structural role than in traditional IPs.

Three vibro-acoustic analysis using Finite Element Method (FEM) is presented. The first analysis is a three-dimensional (3D), interior acoustic, vehicle cabin model, where the modal density and natural frequencies are discussed. The second example is a bi-dimensional (2D) fluid-structure model of the vehicle cabin. In this analysis the main results of the coupled free vibration analysis are presented and discussed. The third example illustrates the use of DtN (Dirichlet-to-Neumann) Map, for exterior acoustic analysis. The DtN Kernel for two dimension problem is presented, and the finite element form is derived. A simple bi-dimensional problem of acoustic radiation from the propulsion system is obtainned.

An assessment model has been developed to determine the piston slap impact forces. This model uses Reynolds' theory for fluid film squeezing to obtain the time history of this impact force. The oil is treated as a damper and the air bubbles entrapped into the oil as a spring. An error of up to one order is found when the stiffness due to the entrapped air is not considered. In this case, the Reynolds theory over predicts the impact forces, compared with experimentally obtained impact forces. The results of this development are used to determine the piston slap in a motored internal combustion engine.

Since wear is a not a material property, but a tribological system property, it is of great importance to know the wear, friction and lubrication behavior of materials tested in bench equipment. This work presents reciprocating pin-on-plate bench tests results, with gas nitrided stainless steel pins and gray cast iron plates. The testing conditions were 0.5 and 3.2 Hz frequency, 20 and 600N applied load and 100 and 150 °C. Under these conditions, mild to severe wear transition was observed. It was noticed noise emission changes at wear transition. This noise change could be used to verify wear transition mechanism.

Due to their inherent advantages, goods transports on the road are indispensable. The permanently increasing competitive and legal requirements demand the exploitation of all technological and engineering possibilities. The high standard of commercial vehicle technology now attained means that new ways must be found of utilizing the remaining scope for further progress, e.g. by increased application of intelligent vehicle systems. This contribution describes such electronic systems. These systems will assist and relieve stress from the driver. Moreover, the possibilities of electronic intelligence will lead to an outstanding increase of active safety and transport efficiency of future vehicle generations [1].

The aim of this paper is to discuss some of the difficulties found in the fulfilment of selected QS9000 (2a edition of '95) requirements, derived from samples of cases witnessed during 3rd party assessments carried out by Lloyd's Register Quality Assurance (LRQA) assessors from São Paulo Business Centre, in suppliers of the automotive industry including large and small organizations active in South America, particularly Brazil and Argentina. The “cases” are herewith presented with references to the applicable QS9000 requirements, usual interpretations sampled from assessed companies and the common understanding applied by LRQA assessors based on the IASG interpretations (December '97 edition), internal training and previous experiences.

Thermal durability of Pt/Rh and Pd/Rh three-way catalysts has been improved by developing new methods of incorporating ceria into formulations, and by identifying components which enhance stability of the oxygen storage characteristics. This increased thermal durability has allowed vehicle manufacturers to place catalysts nearer to the exhaust manifold, and obtain concomitant reductions in test cycle emissions without compromising catalyst durability. In addition, appropriate incorporation of selected promoters into these formulations has improved the sulfur tolerance of Pd/Rh catalyst technology. These effects are demonstrated by vehicle and bench engine evaluations after high temperature engine ageing.

The use of new methodologies to develop new designs for PTFE oil seals has been researched in the near past by many authors and oil seal makers (1) mainly based on finite element analysis,using their own nonlinear modeling (2) and measurement checks. This paper will present a similar approach using FEA as a engineering tool with addition of another known technique called DOE, Design of Experiment ( or Tagushi Method) focusing on a specific problem in our industry. Although, both tools are well known in engineer design our personal experience with many Brazilian and foreign colleagues has shown us a different environment. Therefore, another goal is not only to present a study of oil seals mainly for interested oil seals manufactures and customers, it but also to show a concrete example and the possibilities to expand their use in other branches of the engineering.

Advances in technologies are driven by many factors, but must align with market trends to be successful. An overview of global market trends affecting the automotive industry is presented. The trends of safety, comfort & convenience, and fuel economy/energy are discussed in more detail. Examples of advanced technologies that could be used to address the changing market environment are explained. Trends towards more environmentally friendly products and processes, as well as the vehicle manufacturers' interest in integrated modules, are discussed briefly.