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Fierce competition demands more and more consideration for raw materials that are price competitive without the sacrifice of technical results. High and very often fluctuating raw material costs and availability challenge and complicate the calculation for brake pads raw materials. Therefore there is a strong demand for raw materials with high technical performance at stable predictable costs. For these reasons micaceous Iron Oxide (MIO) is evaluated. A case study describes the substitution of two well-established materials Zirconium Silicate and Potassium Titanate by micaceous iron oxide MIO in disk brake pads. MIO is a naturally occurring mineral with lamellar particle shape. The study compares the addition of 3 wt-% and 6 wt-% of Zirconium Silicate, Potassium Titanate and of MIO in a low-metallic formulation for disk brake pads. Regarding technical performance several properties are evaluated. Tests for friction coefficients are carried out according to the AK-Master SAE J2522.

An experiment was conducted to measure sound pressure levels onboard Mir space station during the docking mission of Space Transportation System (STS)-74. Past Mir measurement data suggested the existence of higher noise levels than those considered acceptable for the International Space Station (ISS). With a separate noise specification to be determined for the Russian Segment (RS) of ISS, current noise level data were required as an analog for acoustic modeling and evaluation. Although high, measurement results showed substantially lower sound pressure levels from that of the historical data. Additional quantitative data collected from an audio dosimeter confirmed the findings.

The aim of the “Microaccéléromètre” experiment is to perform a microgravity characterization of the Russian MIR space station environment. This experiment has been used in 1992 and 1993 flights to characterize the disturbing sources in the different modules of the station during different activity periods. The sensor head is a three axis piezoelectric accelerometer working in a bandwidth from 0.1 Hz to 400 Hz. A special post-processing software has been developed by CNES to analyse the different signal classes (continuous or transient phenomena). This analysis has provided a lot of knowledges about the MIR microgravity environment. Both time and frequency signatures of significant events recorded in the MIR station have been successfully identified with this experiment.

The Surface Protected Ablator (SPA) is a lightweight and cost effective thermal protection for single use reentry capsules. It is characterised by a combination of load carrying structure, ablator and abrasion protection system. A simulation software has been developed to predict the thermal behaviour of the SPA during plasma wind tunnel tests and under atmospheric reentry conditions. Test samples have been exposed to different aerothermal heat fluxes. Test results have been used to calibrate the numerical model and to determine unknown properties of the ablative material. The calibrated model was applied for accurate flight predictions of the MIRKA reentry.

Marking an automotive milestone, microcomputer control has been introduced to a production automobile. The MISAR Ignition System is standard equipment on the 1977 Oldsmobile Toronado which is the first production automobile ever to be equipped with an electronic digital microprocessor. This technological development is the first step toward the use of a programmable digital computer to manage complex vehicle and engine control functions and provide a new dimension of driver convenience. This paper explains the significance of ignition spark timing in internal combustion engines and describes how the MISAR System provides almost infinite advance curve flexibility to meet the requirements for fuel economy, engine performance and exhaust emissions. The hardware components of the system are described including the microprocessor and the various engine sensors. Finally, a brief operational description shows how the system functions to compute and execute the desired ignition commands.

MISRA (The Motor Industry Software Reliability Association) develops practical guidance to assist the developers of safety-related systems in the automotive industry and other sectors in implementing safe and reliable systems. This paper presents a short overview of MISRA's ongoing activities, with particular emphasis on guidance being produced in two areas: process measures for safety-related systems engineering, and product measures for safety-related systems development. Subsequent papers in the session give more details on these activities.

The evolution of cryogenic liquids from laboratory curiosities into practical missile applications has dictated new requirements for the storage, transfer, and utilization of substances at extremely low temperatures. Consideration of the heat-sink capacities of cryogenic liquids reveals a tremendous application potential for positive-displacement pumps and motors, operating on liquefied gases, in aircraft and missile auxiliary power systems. As Assistant Chief Engineer of Vickers Incorporated, Aero Hydraulics Division, I have supervised the development of special aircraft devices. These include lightweight pumps and motors, auxiliary power units, and turbine engine starting equipment.

A newly developed turbocharging system, named MIXPC, is proposed and the performance of the proposed system applied to diesel engines is evaluated. The aim of this proposed system is to reduce the scavenging interference between cylinders, and to lower the pumping loss in cylinders and the brake specific fuel consumption. In addition, exhaust manifolds of simplified design can be constructed with small dimensions, low weight and a single turbine entry. A simulation code based on a second-order FVM+TVD (finite volume method + total variation diminishing) is developed and used to simulate engines with MIXPC. By simulating a 16V280ZJG diesel engine using the MPC turbocharging system and MIXPC, it is found that not only the average scavenging coefficient of MIXPC is larger than that of MPC, but also cylinders of MIXPC have more homogeneous scavenging coefficients than that of MPC, and the pumping loss and BSFC of MIXPC are lower than those of MPC.

The paper is based upon the results of tests made by the Purdue Engineering Experiment Station to study the effect upon engine performance of varying the proportions of fuel to air in the mixture, and its object is to determine the variation in the mixture requirements of an engine at different rates of flow of air through the carbureter. The method of conducting the tests is described. The results are plotted in the charts shown and are discussed in some detail, special discussion regarding the effect of speed and load being presented, and the facts brought out by the tests are summarized. In the general discussion that follows, four definite conclusions regarding the richness of the fuel mixture in its relation to the maximum power are stated, and a like number of definite conclusions concerning the richness of the mixture in relation to maximum efficiency are also given.

The Multi-Layer Steel (MLS) cylinder head gasket's combustion seal feature that we commonly refer to as a stopper, is a zone of the gasket at the bore opening which is thicker than the rest of the gasket. MLS gaskets with stoppers have traditionally been constructed of either a thin folded layer (0.10-0.15mm), an embossed spacer layer, a welded shim, or combinations of multiple layers folded in complex relationships. The “Wave Stopper” design is a new method of integrating the stopper effect into an active layer (spring steel layer with mechanical embossments functioning as springs). A single layer with the wave stopper can now perform the double function of both a stopper and an active layer with one layer. The wave stopper height can be optimized to meet the rigidity requirements of each individual engine, and can even be easily contoured to provide topography if needed. We're not locked into a single constant stopper thickness all around the bore.

MLS (Multi-layer steel) CHG ( Cylinder Head gasket) designs play a major role in today's sealing approach for internal combustion engine. However, as a member between cylinder block and cylinder head, it not only has a sealing function, but also influences the hardware structure. The knowledge of their interaction is critical to fulfill all necessary requirements. This paper discusses different MLS CHG designs and how they influence the hardware's structure while maintaining the seal of the assembly. Therefore, we investigate major parameters like sealing stress, sealing gap lift-off, bore distortion and etc. A comparison is made between different designs, using experimental data as well as finite element analysis. Because of the vast number of designs and their interactions between the hardware and gasket, the focus is on basic trends of their influences.

This paper discusses the results of a series of flight tests conducted at various locations. The purpose of the flights were to obtain accuracy performance measures. Flights were conducted at the FAA Technical Center, Atlantic City, N.J., Tamiami Airport in Miami, Florida, and Lebanon, New Hampshire. The flight tests conducted at Atlantic City included computed centerline approaches in which the azimuth transmitter was offset 500 feet and 1000 feet from the runway centerline. The Lebanon flight test consisted of a computed centerline approach where the azimuth is more than 400 feet off the runway centerline. A series of precision approaches were conducted during the flight tests at Tamiami Airport. These included a multi-segment glide path on the runway where the equipment was sited, an approach to a parallel runway (3500 feet offset) and an approach to an intersecting runway.

This paper discusses the integration of a Microwave Landing System and an Inertial Navigation System. The system is built by Lear Siegler, Inc. (LSI) for pallet installation on the USAF C-141 transport aircraft. The main emphasis of this paper is the MLS/INS integration using a constant gain filter algorithm. The system was simulated in the lab, bench tested, and later flight tested on the C-141 using the MLS facilities at Wallops Island, VA. This work was completed for the USAF/ASD under Contract F33615-85-C-3603.