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This study investigates occupant containment characteristics of tempered and laminated automotive moveable side glass in rollover collisions. FMVSS 216 test protocols were used to induce roof damage or sheet metal damage around the window opening in Lincoln Navigators equipped with tempered and laminated side glass. Dummy-drop tests were then performed to investigate relative containment. The results demonstrate that, for rollovers in which the window structure is compromised, tempered side glass and laminated side glass perform comparably relative to occupant containment. Also discussed are the general strength characteristics of different types of glass construction, the availability of laminated side glass in recent model U.S. vehicles, and anecdotal data supporting the conclusions of testing.

An outer loop guidance architecture was designed to control autonomous aerial refueling mission from the trail aircraft side. The design utilized bank, yaw rate, velocity and climb rate commands implemented using a previously developed adaptive trajectory concept. The concept was based on position error feedback that was used to control trail aircraft overshoot and tracking about the lead aircraft refueling point. To demonstrate this application, an open loop linear trail aircraft model at a given flight condition was selected. Inner loop control laws were designed using Linear Quadratic Regulator feedback controller and Balanced Deviation theory. The outer loop guidance architecture was then added to implement the application. The performance of the system was then evaluated for a selected position error, and disturbance.

The timing of lubricating oil changes for passenger vehicles are based on set time or mileage intervals specified by their manufacturers. A few vehicle manufacturers use more sophisticated methods such as logging the engine speed and temperature and calculating the oil change intervals from this data. Neither technique tells the vehicle user anything about the true state of the oil. A novel form of viscosity sensor based on a vibrating piezoceramic element has been developed. Based on the output from such a device, a more accurate determination of the oil change interval can be made and abnormal conditions (such as the leakage of fuels into the lubricating oil) can be detected. This paper gives a brief description of the device itself and shows results from prototype samples.

Of the many research approaches investigated over the years to measure the lubrication properties of aviation turbine fuels, the Ball-on-Cylinder Lubricity Evaluator (BOCLE) has emerged as the most significant test. BOCLE was originally a lubricant research device modified for low viscosity jet fuel when the Air Force encountered fuel control problems in 1965 with JP-4. It proved to be capable of detecting the presence of additives such as corrosion inhibitors which improve boundary lubrication properties and also the absence of natural lubricity agents in highly refined jet fuel. The Coordinating Research Council carried out several programs to investigate test variables such as cylinder type, humidity control and load. A semi-automated version using Falex test rings has now been commercialized and is being used to test fuels from aircraft experiencing abnormal pump wear and fuel control hang-up.

There is an ongoing interest in biodegradable hydraulic fluids. Biodegradable fluids are often considered to include only vegetable oils, polyol esters and diester base stocks. However, other fluid base stocks including highly refined mineral oils, poly(alpha olefins) and fire-resistant fluids such as water-glycol hydraulic fluids are also biodegradable fluid alternatives. This paper will provide an overview of the international literature on biodegradable fluids, various international testing protocol, fluid base stocks, effect of oxidative stability, material compatibility and pump performance.

Development of reliable magnesium (Mg) to steel joining methods is one of the critical issues in broader applications of Mg in automotive body construction. Ultrasonic spot welding (USW) has been demonstrated successfully to join Mg to steel and to achieve strong joints. In this study, corrosion test of ultrasonic spot welds between 1.6 mm thick Mg AZ31B-H24 and 0.8 mm thick galvanized mild steel, without and with adhesive, was conducted. Adhesive used was a one-component, heat-cured epoxy material, and was applied between overlapped sheets before USW. Corrosion test was conducted with an automotive cyclic corrosion test, which includes cyclic exposures of dipping in the 0.5% sodium chloride (NaCl) bath, a constant humidity environment, and a drying period. Lap shear strength of the joints decreased with the cycles of corrosion exposure. Good joint strengths were retained at the end of 30-cycle test.

The aerodynamics of the STOL aircraft can experience significant changes in proximity to the ground. A review of the existing data base and methodologies has been made and the results of that review are presented in this paper. The existing data show that in ground proximity the STOL aircraft will generally experience a reduction in the lift component regardless of the lifting configuration. Those configurations with integrated power and lift systems will have an additional effect of ground induced aerodynamic changes. This paper will discuss the existing data base and the deficiencies of that data base.

Reported tensile and fatigue properties of die cast AZ91D and AM60B magnesium alloys indicate that those values depend on the size and shape of the test samples and their global porosities. This paper reviews the mechanical properties reported in the open literature for these die cast alloys and indicates that section thickness and global porosity are inadequate for predicting the tensile and fatigue properties of die cast AZ91D and AM60B magnesium alloys.

Recreational marine engine operation effects water quality as well as air quality. Significant quantities of hydrocarbons are discharged into the rivers, lakes, and estuaries used as recreational boating waters. In order to investigate the impact of recreational marine engine operation on water quality, a MerCruiser 3.0LX four-cylinder four-stroke inboard engine and a Mercury 650 two-cylinder two-stroke outboard engine were tested using EPA required certification procedures. Both engines were tested with exhaust gas/cooling water mixing (scrubbing) in the exhaust stream using both freshwater and saltwater. Additionally, the inboard engine was tested without exhaust scrubbing. Gaseous emissions (HC, NOX, CO, and CO2) from the engines were continuously measured using a constant volume sampling system. Both exhaust gas and cooling water samples were collected and speciated for hydrocarbon species present.

A novel two stroke cycle diesel engine is evaluated as a general aviation aircraft powerplant. Two certificated spark-ignited gasoline reciprocating engines are also evaluated in the same aircraft. The evaluation of aircraft propulsion performance considered only the effects of altered powerplant parameters on the range of an aircraft having a fixed gross weight and payload cruising at a given lift/drag ratio. Thermodynamic analysis finds the diesel engine can have a sea level power rating exceeding the 10,000 foot cruise power requirement by 55% with nearly equal specific fuel consumption, a low engine speed and a modest cylinder pressure. It uses a single-stage, radial turbocharger without intercooling or auxiliary mechanical scavenging. The diesel engine can significantly increase the range of a particular airplane now powered by a certificated turboprop engine. The candidate gasoline engines could not equal the turboprop-powered aircraft performance.

This paper provides a review of the fatigue properties reported in the open literature for die cast magnesium-based alloys. Recently developed fatigue data, in the form of stress versus number of cycles to failure for bending fatigue (R=-1), are presented for die cast AM60B and AZ91D alloy specimens with thicknesses between 1 and 10 mm. The effects of specimen thickness and macrostructural features, such as porosity distributions and surface features (parting line and ejection pin marks), on the fatigue data are discussed.

Modern approaches to durability assurance in ground vehicle design are reviewed in the context of recent developments in computer-based analytical and experimental tools for use by designers and development engineers. Examples, using an automotive wheel assembly, are presented to illustrate the application of fatigue analysis in product development. Major challenges associated with the linking of various design tools into integrated networks appropriately configured for industrial problem solving are discussed along with an assessment of the potential benefits to be gained from such integration.

Both physical experiments and detailed chemical kinetics studies establish that Sonex micro-chambers imbedded in the walls of the piston bowl of an I.C. engine generate highly reactive intermediate chemical species and radicals- which, when allowed to mix with the fresh charge of the next cycle in the main chamber, substantially alter the chemical kinetics of main chamber combustion. A much more stable overall combustion process is observed, requiring substantially leaner air-fuel ratios than normal, and with much lower ignition temperatures. The net result, without any efficiency penalty, is an engine with an “ultra-clean” exhaust and with a greater tolerance to a wider range of fuels. Crucial to this process is the quenching of the flame in the passages connecting the micro-chambers to the piston bowl. It is flame quenching which enables the incomplete combustion of the charge trapped in the micro-chamber cavities.

The continued availability of leaded specialty aviation gasolines remains as an item of crucial importance in the near-term future of general aviation; however, the development of new piston engines capable of operation with other transportation fuels available in large pools is considered an indispensable element in the long-range survival of the industry. This paper offers a road map that while allowing the continued utilization of the current fleet of piston aircraft, sets the stage for a transition to new piston powerplants and associated aircraft, compatible with widely available transportation fuels such as motor gasoline based aviation fuels for the lower and some medium performance aircraft, and aviation turbine fuels for the balance of medium and high performance airplanes.

The purpose of this paper is to survey the adverse environmental impacts resulting from motor vehicles, to review technologies developed to address these problems, and to summarize the current status of pollution control programs around the world.

Rapidly industrializing developing countries are now starting to note similar air pollution problems to those of the industrialized world. This paper surveys the adverse environmental impacts resulting from motor vehicles, reviews technologies developed to address these problems, and summarizes the current status of pollution controls around the world. Special focus is on the design of strategies to address the emerging problems of developing countries.

The late and expected improvements in balancing design of hydraulics components to be sure to use real and relatively thick films to enhance the transmission gear of forces and torques with a very low level of friction forces and pratically without heating and wear. The RAFFO process allows high performances, low sensitivity to pollution and small machining cost.

The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

Die cast AZ91D and AM60 magnesium alloy components are finding increasing usage in automotive applications. Both hot and cold chamber die cast components of these alloys generally exhibit several common microstructural features, including “skin”, porosity banding, and porosity distributed about the component centerline. Methods for quantitatively characterizing these microstructural features are described and representative values for skin thicknesses, porosity band dimensions and porosity band locations from selected die castings will be presented. The expected influence of these common microstrucutral features on mechanical properties and acceptability of die cast magnesium components for given applications are discussed.

This numerical study examines the chemical-kinetics mechanism responsible for EGR NOx reduction in standard engines. Also, it investigates the feasibility of using EGR alone in hydrogen-air and methanol-air combustion to help generate and retain the same radicals previously found to be responsible for the inducement of the autoignition (in such mixtures) in IC engines with the SONEX Combustion System (SCS) piston micro-chamber. The analysis is based on a detailed chemical kinetics mechanism (for each fuel) that includes NOx production. The mechanism for H-air-NOx combustion makes use of 19 species and 58 reactions while the methanol-air-NOx mechanism is based on the use of 49 species and 227 reactions. It was earlier postulated that the combination of thermal control and charge dilution provided by the EGR produces an alteration in the combustion mechanisms (for both the hydrogen and methanol cases) that lowers peak cycle temperatures-thus greatly reducing the production of NOx.