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There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

Aerospace structures manufacturers find themselves frequently engaged in large-scale 3D metrology operations, conducting precision measurements over a volume expressed in meters or tens of meters. Such measurements are often done by metrologists or other measurement experts and may be done in a somewhat ad-hoc fashion, i.e., executed in the most appropriate method according to the lights of the individual conducting the measurement. This approach is certainly flexible but there are arguments for invoking a more rigorous process. Production processes, in particular, demand an automated process for all such “routine” measurements. Automated metrology offers a number of advantages including enabling data configuration management, de-skilling of operation, real time input data error checking, enforcement of standards, consistent process execution and automated data archiving. It also reduces training, setup time, data manipulation and analysis time and improves reporting.

This paper provides an overview about the consequences of a 14/42 V - Electrical Power Supply System for the Electrical Interconnection and Switching Technology. It presents design guidelines and solutions for connector systems including advanced applications like fuse and relay boxes and gives an overview of those existing connectors already suited for 42 V and even higher voltages. The problem of arcing due to the increased voltage is discussed for the case that mating and unmating under load has to be taken into consideration. Arcing also has a tremendous impact on the design of 42 V proof relays. Therefore, some basic results be presented along with proposals how these problems can be overcome by appropriate designs. Another part of the paper looks at the electrical power supply system itself. Here interconnection techniques for new battery systems are discussed. Finally, the chances for new technologies are highlighted.

System requirements and Interface Control Drawings (ICDs) make a variety of demands for MIL-STD-1553 remote terminals (RTs). Among these requirements are the need to ensure data integrity and sample data consistency, the need to perform bulk (multi-message) data transfers, and the need to offload the operation of the host CPU to the greatest degree possible. This latter requirement is reflected in such specifications as CPU spare bandwidth. The latest 1553 terminals provide a variety of choices for performing the different types of transfers. This paper provides a discussion of the hardware and software techniques for achieving these objectives. Three different schemes for RT subaddress memory management are presented: single message, circular buffer, and double buffered. For receive and transmit messages, these include fully synchronous single message transfers, asynchronous single message transfers, and multi-message transfers.

A Microprocessor Data Acquisition System has been designed to be cab-mounted in vehicles or used in laboratories to acquire up to 16 channels of test data. This data may be acquired as time-at-level histograms in one or two dimensions with min-max-mean data recovery, time histories, or peaks and valleys stored on digital tape. The system includes a microcomputer-based Playback/Support Box that simplifies playback of data tapes for computer analysis or stand-alone data plotting using a graphics terminal.

Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.

A first attempt to study civil aircraft operations comprehensively, prior to having the airplane, occurred before the initial operation of U.S. subsonic jets. One airline carried out a manual-simulated “paper jet” operation lasting fifteen months. Today, computerized simulation of machines, methods, and operations has become commonplace, and replaces the slide rule and tedious day-by-day inputs of aircraft operational criteria. Computerized simulations are also applied to every aspect of the SST design and operations. These are important, but the results being should be used with caution and judgement.

This paper is a summary of the aerodynamic development of the 1988 Chevrolet and GMC pickup truck. Comprehensive drag reduction work was performed with clay models from the original concept through the detailed full-scale model. In addition, the aerodynamic development included wind rush noise reduction, optimization of engine cooling air flow, and body surface pressures for HVAC performance.

The Cardinal is a Super Short Takeoff and Landing (SSTOL) aircraft, which is designed to fulfill the desire for center-city to center-city travel by utilizing river “barges” for short takeoffs and landings to avoid construction of new runways or heliports. In addition, the Cardinal will fulfill the needs of the U.S. Navy for a Carrier On-board Delivery (COD) aircraft to replace the C-2 Greyhound. Design requirements for the Cardinal included a takeoff ground roll of 300 ft, a landing ground roll of 400 ft, cruise at 350 knots with a range of up to 1500 nm with reserves, payload of 24 passengers and baggage for a commercial version or a military version with a 10,000 lb payload, capable of carrying two GE F110 engines for the F-14D, and a spot factor requirement of 60 feet by 29 feet.

Most of current jet aircraft circulate fuel on the airframe to match heat loads with available heat sink. The demands for thermal management in wide range of air vehicle systems are growing rapidly along with the increased mission power, vehicle survivability, flight speeds, and so on. With improved aircraft performance and growth of heat load created by Aircraft Mounted Accessory Drive (AMAD) system and hydraulic system, effectively removing the large amount of heat load on the aircraft is gaining crucial importance. Fuel is becoming heat transfer fluid of choice for aircraft thermal management since it offers improved heat transfer characteristics and offers fewer system penalties than air. In the scope of this paper, an AMESim model is built which includes airframe fuel and hydraulic systems with AMAD gearbox of a jet trainer aircraft. The integrated model will be evaluated for thermal performance.

The increased occurrence of environmental damage to automotive topcoats and the variety of abrasive conditions to which the coating is subjected have made increasing demands on the properties of these coatings. There is as yet, no single paint chemistry that fulfills these extreme requirements in all respects. On the other hand, the right choice of components in polyurethane can result in excellent etch resistance as well as improved scratch resistance compared to traditional melamine/acrylic systems. This paper will discuss some recent studies in the areas of two-component and one-component polyurethane chemistry, which address these rigorous quality requirements.

A test program was conducted to characterize the impact response of an experimental 2-ply windshield construction with a polyurethane (PUR) plastic inner layer. Windshield impact tests were conducted using a linear impactor test facility. Principle among the findings was that the impact response of prototype PUR 2-ply windshields does not differ that significantly from that of baseline 3-ply HPR (High Penetration Resistance) windshields for the subcompact vehicle geometry tested. However, the impact responses of both PUR 2-ply and 3-ply HPR subcompact vehicle windshields were found to be highly variable. Average performance of either construction could thus be enhanced if ways could be found (and then implemented) to reduce this variability.

The paper presents a numerical study aimed at converting a commercial lightweight 2-Stroke Indirect Injection (IDI) Diesel aircraft engine to Direct Injection(DI). First, a CFD-1D model of the IDI engine was built and calibrated against experiments at the dynamometer bench. This model is the baseline for the comparison between the IDI and the DI combustion systems. The DI chamber design was supported by extensive 3D-CFD simulations, using a customized version of the KIVA-3V code. Once a satisfactory combustion system was identified, its heat release and wall transfer patterns were entered in the CFD-1D model, and a comparison between the IDI and the DI engine was performed, considering the same Air-Fuel Ratio limit. It was found that the DI combustion system yields several advantages: better take-off performance (higher power output), lower fuel consumption at cruise conditions, improved altitude performance, reduced cooling requirements.

The paper describes a numerical study, supported by experiments, on light aircraft 2-Stroke Direct Injected Diesel engines, typically rated up to 110 kW (corresponding to about 150 imperial HP). The engines must be as light as possible and they are to be directly coupled to the propeller, without reduction drive. The ensuing main design constraints are: i) in-cylinder peak pressure as low as possible (typically, no more than 120 bar); ii) maximum rotational speed limited to 2600 rpm. As far as exhaust emissions are concerned, piston aircraft engines remain unregulated but lack of visible smoke is a customer requirement, so that a value of 1 is assumed as maximum Smoke number. For the reasons clarified in the paper, only three cylinder in line engines are investigated. Reference is made to two types of scavenging and combustion systems, designed by the authors with the assistance of state-of-the-art CFD tools and described in detail in a parallel paper.

This paper documents the processes and methods used by the Ford GT team to meet aerodynamic targets. Methods included Computational Fluid Dynamics (CFD) analysis, wind tunnel experiments (both full-size and scale model), and on-road experiments and measurements. The goal of the team was to enhance both the high-speed stability and track performance of the GT. As a result of the development process, significant front and rear downforce was achieved while meeting the overall drag target.

This paper is intended to give a general overview of the key aerodynamic developments for the 2006 Chevrolet Corvette C6 Z06. Significant computational and wind tunnel time were used to develop the 2006 Z06 to provide it with improved high speed stability, increased cooling capability and equivalent drag compared to the 2004 Chevrolet Corvette C5 Z06.

The U. S. Coast Guard has recently put into service new 210 ft cutters designed for search and rescue work, law enforcement, oceanographic work, and possible future ASW. This paper outlines the structure and capabilities of the vessel. An important feature of the cutter is its helicopter handling facilities, which have greatly increased the cutter's search and rescue capability by extending the area it can cover. The cutter is the first in Coast Guard service to be powered by a combination diesel engine and gas turbine installation. The combination gives a top speed of 18 knots and a cruising range of 5000 miles.

Aircraft potable (drinking) water systems haven’t changed significantly in the last half-century. These systems consist of cylindrical water tanks pressurized by bleed air from the jet engines, with insulated stainless steel distribution lines. What has changed recently is the increase in the possibility of aircraft picking up contaminated drinking water at foreign and domestic stops. Customer awareness of these problems has also changed - to the point where having reliable drinking water is now a competitive issue among airlines. Old style potable water systems that are used on modern aircraft are high maintenance and exacerbate the growth of microbes because the water is static much of the time. The integrity of some pressurized water tanks are also a concern after years of use. Cost-effective mechanical and biological solutions exist that can significantly reduce the amount of chemicals added and provide good potable water.