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A concept for an advanced defense suppression system using an unmanned (bomb rack launched, 500 lb class air launched) vehicle with cruise/loiter/attack capabilities has been developed. Guidance commands are provided by either a radiation sensor or a flight reference unit depending upon the phase of the trajectory (anti-radiation during attack/flight reference during cruise and loiter). Two airframe configurations (mono wing and cruciform) were analyzed for the three phases of the flight trajectory. Overall systems requirements such as speed, weight, thrust levels, maneuverability, cross section and control configurations were formulated.

The Harassment Weapon System HWS) program has demonstrated the practical utility of a mini drone based weapons system. Completed studies and analysis provide a solid basis for HWS entering engineering development with a lethal system which is effective against all components of the Warsaw Pact air defense network. This paper provides a conceptual framework for integration of a mini drone based weapons system as a part of the total force structure.

Modern jet transport aircraft structures, although certified in accordance with current regulations, have been designed using damage-tolerance practices which resulted in an excellent safety record. In spite of these practices unpredictable cracks and corrosion occur in service. The new regulations recognize these developments and place special emphasis on certification of damage-tolerant structures. Present damage-tolerance methods and procedures are discussed. Analytical methods are described which account for the upgrading of the new regulations.

Amendments relating to the structural fatigue evaluation requirements are described. The amendments improve and update the air-worthiness standards applicable to the type certification of civil transport category airplanes. They take into account state-of-the-art developments and accumulated service experience. The authority for and origin of the related rules is also briefly traced. The interest in world-wide acceptance of these new standards is noted.

The Wiegand Effect - a new magnetic pulse generating technology requiring no electrical input - has been recently introduced as the distributor trigger in a capacitive discharge ignition system for high-performance applications. In this paper an inductive system is described, utilizing a Wiegand trigger which provides constant angular dwell. The magnetic circuit of the Wiegand trigger has been further developed to permit its easy incorporation in a conventional automotive distributor. All of the electronics, including a unique electronic advance circuit are incorporated in the distributor bowl.

An adhesive bonding study was conducted to generate data required for the full utilization of graphite and continuous glass reinforced plastics. From the screening of a wide range of acrylic, epoxy, and urethane adhesives, one adhesive of each kind was selected for further evaluation. The screening was done on the basis of strength comparisons of adhesive bonded samples at elevated temperatures and under different surface treatments, cure cycle, and bond thickness conditions. Environmental effects, such as heat and humidity exposure on pre-stressed and unstressed samples, have also been studied for some of the selected adhesives.

Structural bonding of reinforced plastics has been successfully utilized for ten years or more in a variety of automotive applications; such as, truck front-end assemblies, pickup box covers, utility vehicle tops, etc. Uses have been for relatively low-volume applications, and the adhesive bonding has been accomplished by manual application of the adhesive rather than with automated equipment. With the emerging interest in utilizing reinforced plastics for applications on large-volume vehicles such as passenger cars and light trucks, it becomes necessary to develop ways of speeding up the adhesive bonding operation to keep up with assembly line requirements. This paper will present our background and experience in structural bonding of reinforced plastics and discuss new technology in adhesives, application equipment, and high-strength composites for future uses in the automotive industry.

Use of structural adhesives on automotive assembly lines requires systems compatible with a variety of metal and polymer substrates, minimal surface preparation and short cure or part handling times. Various types of structural adhesives have been considered in relation to the above needs. Some adhesive types bond well to unprepared surfaces, but all give improved performance with proper surface treatment. Host structural adhesives need temperatures ranging from 65°C (150°F) to as high as 230°C (450°F) to give the desired short cure times. Good bond strengths can be achieved under such cure conditions. New modified acrylic adhesives show promise for fast cure use at ambient temperatures.

Powered manlift or aerial devices vary in cost, complexity and size from a simple truck mounted ladder to 150 foot devices mounted on crane carrier chassis. Considerations pertinent to the purchase of one are - height of work to be performed, insulated or non-insulated, load to be lifted, required side reach, travel height, number and span of outriggers, and whether the unit should articulate fully, non-overcenter or be a telescoping boom. Ease of maintenance is also a consideration. Articulated units often give a better choice of working positions and facilitate field side work. Telescoping units are generally preferred when working through heavy trees. The purchase of a device larger than required can squander much capital both in the device itself and in the chassis required to mount the device. Consideration must also be given to whether or not plant is to be placed from the unit and what type of tooling will be used in conjunction with it.

The modern digger derrick is a complex machine which can perform numerous operations. A variety of machines are available and the user must match his requirements to the products offered if he is to procure the most efficient one. The primary variables that are reviewed in detail are configuration, capacity, digging requirements, and stability. Controls and accessories are briefly reviewed. Two work sheets are presented. The first provides assistance in determining the configuration best suited for the user's needs and, the second serves as a check list to assure that the final specification has not omitted necessary information.

Utility derricks are normally offered in three different types of mounting and utility lifts are normally offered in two different types of mounting. The correct mounting is not necessarily the most expensive nor perhaps the one you have been using all these past years. There are some important factors you must consider before mounting your mechanized equipment.

The lead-acid couple is potentially capable of fulfilling the battery requirement for high performance electric delivery vehicles in the one tonne payload category. Development of such a battery, combining high energy density and good cycle life, involves extensive and painstaking testing. During the course of the Lucas development programme test methods and procedures have been evolved to ensure that the battery array with its supporting equipment is capable of fully performing the tasks required of it in such an application. Much of the experience gained is applicable to any electrochemical couple being developed for electric vehicle use.

A cylinder pressure time history has long been used as an indication of the performance of internal combustion engines. Recently the use of cylinder pressure has been proposed for the knock adaptive closed loop control of spark advance (1, 2)*. The ultimate practicality of such a scheme depends heavily on the cost and reliability of a sensor to make this measurement. This paper describes the design, associated analysis, and the experimental performance of a potentially inexpensive sensor. The transducer is shown to be suitable for determination of the crank angle at the peak cylinder pressure and for detection of incipient detonation through the associated high frequency cylinder pressure oscillations. Furthermore, implementation of the sensor in a closed loop spark control system is briefly described. The sensor has proven to be adequate for spark advance control purposes.

The change in the resistance of titanium dioxide with oxygen partial pressure is utilized to obtain an air-to-fuel ratio sensor. TiO2 material properties, sensor components and performance characteristics are discussed. Some results of engine dynamometer and vehicle tests of sensor performance and durability are presented.

High-quality, low-cost automotive sensors are the key to making precise electronic engine control practical. This paper describes four automotive sensors: a temperature sensor, a linear position sensor, a rotary position sensor, and a crankshaft position sensor. The description covers the design approach, the test procedures, the production processes, and the quality assurance measures followed by an established high volume automotive supplier.

The characteristics of ZrO2-type oxygen sensors for closed-loop control of the air-fuel mixture for automotive engines were investigated. New sensors, sensors tested in dynamometers and road vehicles, and lead-poisoned sensors were characterized as to their performance in terms of voltage output, switching response, internal resistance and voltage-λ switching behavior. New sensors behaved as ideal sensors at temperatures above 400°C, and behaved non-ideally at temperatures below 350°C. Sensors subjected to dynamometer and vehicle tests showed a gradual degradation in output voltage and steepness of their voltage-λ switch. Their internal resistances and lean-to-rich switching times increased with use while the rich-to-lean switching times decreased. Self-recovery of a sensor from lead poisoning occurred during subsequent vehicle operation with lead-free fuel.

A new type of Ratiometric Temperature Sensor has been developed which shows considerable promise in the measurement of engine intake manifold fuel/air charge temperatures. The device consists of a conductive plastic potentiometer, driven by an integral bimetallic sensing element. The Ratiometric Temperature Sensor closely tracks the rapidly fluctuating temperature of the fuel/air charge, and provides a linear ratiometric output voltage ranging from 15% to 85% of the total supply voltage over the sensed temperature range of -40°C to +125°C. Output accuracy is ±3°C over a temperature range of +20°C to +100°C.

A new technology for temperature sensors has been developed. The sensors are extremely rugged, capable of withstanding the most rigorous environments, and they are expected to result in very inexpensive product manufacture. This paper discusses the evolution of the design of metal core hybrid substrates and the principles of construction of a temperature sensor as a hybrid circuit on a metal core substrate. Sensor performance characteristics and cost are also explored. A discussion of the linearity of voltage response to temperature is included, and data are presented on the performance of the sensor in various environments. The paper concludes that the new sensor is suitable for operation in all environments found in automotive applications, and that its range is sufficient to accommodate all of the control functions currently found in the literature.

The primary force behind composite materials development for aircraft applications was to achieve weight savings in weight-critical regions. In today's aircraft technology, graphite/epoxy composites are fulfilling this need and are being used as structural materials in the form of cross-plied fiber-reinforced laminates for conventional monolithic wing/empennage skins and substructure, or as face sheets on honeycomb-type structure. All metal components have been replaced by composite structure on aircraft such as the B-1, F-18, and AV-8B. Weight/cost savings were demonstrated for the B-1 aircraft in which not only weight savings, but also cost competitiveness were the goals. The next-generation aircraft will incorporate composites in a significantly larger proportion of the airframe structure to exploit more fully all advantageous characteristics of advanced composite structure (strength, stiffness, tailorability, weight, and fabrication cost savings).

The composite design for the B-1 stabilizer was developed to satisfy all of the form, fit, and functional requirements of the aircraft and to be competitive with the metal stabilizer on both a weight and production cost basis. Actual weights of the composite stabilizer show a 15 percent savings for the total stabilizer and a 21 percent savings for the composite torque box over the existing metal configuration. Cost savings of 17 to 20 percent are estimated in production. The design that evolved from this effort, the test data generated to validate the concept, the fabrication procedures used, and production cost comparisons are presented.