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Military and commercial turbofan STOL transport work at the Douglas Aircraft Company during the past four years has led to the consideration of commonality between the USAF Medium STOL Transport and a short-range, medium-sized commercial STOL transport. General requirements for the two airplanes appear to be similar and include a cruise speed of Mach 0.75-0.80 for a 500-nautical mile range after takeoff from a 2000-foot airstrip. Both require a wide body; and the payload, furnishings, and equipment yield comparable STOL takeoff weights. Both can be designed with a high wing, a moderate wing loading, and the same STOL lifting concept. A common engine size appears feasible, and basic engine characteristics such as bypass ratio need not be different. Results of a preliminary commonality study are presented in which several cases with varying degrees of commonality are evaluated in terms of costs.

This paper surveys publications on automotive powertrain control, relating to modern GTDI (Gasoline Turbocharged Direct Injection) engines. The requirements for gasoline engines are optimising the airpath but future legislation suggests not only a finely controlled airpath but also some level of electrification. Fundamentals of controls modelling are revisited and advancements are highlighted. In particular, a modern GTDI airpath is presented based on basic building blocks (volumes, turbocharger, throttle, valves and variable cam timing or VCT) with an example of a system interaction, based on boost pressure and lambda control. Further, an advanced airpath could be considered with applications to downsizing and fuel economy. A further electrification step is reviewed which involves interactions with the airpath and requires a robust energy management strategy. Examples are taken of energy recovery and e-machine placement.

Market trends for increased engine power and more electrical energy on the powergrid (3kW+), along with customer demands for fuel consumption improvements and emissions reduction, are driving requirements for component electrification, including turbochargers. GTDI engines waste significant exhaust enthalpy; even at moderate loads the WG (Wastegate) starts to open to regulate the turbine power. This action is required to reduce EBP (Exhaust Back Pressure). Another factor is catalyst protection, where the emissions device is placed downstream turbine. Lambda enrichment or over-fueling is used to perform this. However, the turbine has a temperature drop across it when used for energy recovery. Since catalyst performance is critical for emissions, the only reasonable location for an additional device is downstream of it. This is a challenge for any additional energy recovery, but a smaller turbine is a design requirement, optimized to operate at lower pressure ratios.

Claims and counter-claims as to the deceleration possible under certain conditions, especially when applied to the legal questions arising at the time of an accident, induced the author to make an investigation of the subject. An attempt has been made to include all the variables that are of significance or of sufficient magnitude to affect appreciably the performance of a car under a given set of conditions of the vehicle or of the environment. Inasmuch as the calculations are simplified by doing so and because the difference between the amounts of deceleration and of power involved are small, the assumption is made that the maximum deceleration occurs when the wheels are locked, rather than when they are still rotating. The stopping-distances, theoretically obtained, apply to level-road conditions only.

DURING the war the trend of tractor engine design toward increased efficiency resulted in many improvements and discoveries in accessories, not the least of which is the carbureter air-cleaner. The value of air-cleaners is now fully recognized and they are used as standard equipment on the majority of tractors. Air-cleaners are classified into groups as follows: (a) cleaners having cloths or screens, or both, to catch dust; (b) inertia cleaners; (c) those employing water or some other liquid to trap dirt and (d) centrifugal or gravity cleaners. The first class is practically obsolete; illustrations of two of this type are shown. Inertia cleaners are not widely used, but present possibilities. Liquid cleaners of various designs are in considerable use. The author believes that the slight advantage in efficiency of this type over the better class of dry-type cleaners is not sufficient to compensate for their greater size and difficulty of operation.

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.