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Some of the more general types of dynamic vibration that exist in aircraft, particularly the powerplant components, are reviewed for reciprocating and turbine engines as well as helicopter and unconventional drive systems. The responsiveness of various components to the source of excitation, resulting in either resonant or nonresonant (forced) vibration, is discussed. The importance of evaluating the fatigue life of a component at varying load conditions, both in the laboratory and field, is stressed.

The General Purpose Work Station (GPWS) is a laboratory multi-use facility, as demonstrated during the Spacelab Life Sciences 1 (SLS-1) flight. The unit provided particulate containment under varying conditions, served as an effective work space for manipulating live animals, e.g., rats, served as a containment facility for fixatives, and was proposed for use to conduct in-flight maintenance during connector pin repair. The cabinet has a front door large enough to allow installation of a full-size microscope in-flight and is outfitted with a side window to allow delivery of items into the cabinet without exposure to the spacelab atmosphere. Additional support subsystems include inside cabinet mounting, surgical glove fine manipulations capability, and alternating or direct current power supply for experiment equipment, as will be demonstrated during Spacelab J.

This paper presents an optimization model that was developed to generate optimal alternative sets of data elements for crash event data recorders (EDRs) on commercial motor vehicles, since EDRs can provide important information about crashes to improve vehicle safety. The input data for this optimization model was from the following United States Department of Transportation (USDOT) reports: Development of Requirements and Functional Specifications for Crash Event Data Recorders (EDRs) on Commercial Motor Vehicles and EDR Volume II - Supplemental Findings for Trucks, Motorcoaches, and School Buses (May 2002). The purpose of this optimization model was to provide useful and cost effective alternative sets of EDR data elements for a “real world” application.

Flyover noise levels of turbojet-powered airplanes are dominated by the low-frequency roar of the jet-exhaust noise at both takeoff and approach power settings. Jet-noise suppressors developed for these turbojet engines did reduce some-what the noise levels under the takeoff flight path but did not reduce the levels under the approach flight path. Low-bypass-ratio turbofan engines produced less jet-exhaust noise than the turbojet engines, but the discrete-frequency components of the turbomachinery noise were more prominent. A research program, conducted for NASA, showed that the installation of acoustically absorptive duct linings could yield significant reduction in the level of the turbomachinery noise, on the JT3D-powered transports at approach power settings. Expectations relating to installations of similar material on JT8D-powered transports are described.

A numerical method for generating a blockloading profile from a rainflow histogram is described. Unlike previous techniques, this method produces a blockloading profile which, when rainflow-counted, yields a rainflow histogram identical to the original. When implemented with modern data acquisition and signal-processing techniques, this generation method provides a means of developing blockloading test profiles which are correlated with actual service data. This key benefit elevates existing simple testing systems as useful and productive tools despite the emrgence of more complex testing systems.

The provision of two-way communications between the central traffic control center and all vehicles, which are equipped with route guidance systems (RGS), makes it possible to assemble very efficiently a continuous estimate of the prevailing dynamic or time-varying O-D (Origin-Destination) matrix. This paper describes the mathematics of a four step procedure for developing such a time varying O-D matrix from vehicle probe data and discusses the important statistical limitations of the final O-D estimates. It is shown that, unless there is a very high level of market penetration in the network, the resulting O-D estimate will contain such a high level of statistical uncertainty as to render it of limited practical value.

Various conditions can cause an aircraft to assume a roll or tilt angle on the runway, causing the nose tire(s) to produce significant uncommanded cornering forces if the nose gear is free to swivel. An experimental investigation was conducted using a unique towing system to measure the cornering forces generated by a tilted aircraft tire. The effects of various parameters on these cornering forces including tilt angle, trail, rake angle, tire inflation pressure, vertical load, and twin-tire configuration were evaluated. Corotating twin-tires produced the most severe cornering forces due to tilt angle. A discussion of certain design and operational considerations is included.

This paper announces the intention of the SAE AS-1 Committee to standardize on a common framework for modeling and defining aircraft-store logical interfaces, called GASIF. The paper then advocates a common framework that might serve as a suitable starting point for this project. The purpose of GASIF is to foster greater interoperability between aircraft and stores through coordinated standards development and programs. FIELD OF APPLICATION - The field of application for this paper is military aircraft/store avionics, where a ‘store’ may be defined as any in-flight separable device (such as an air-launched weapon) that when loaded on an aircraft allows it to perform a specific mission.

The CATHODE RAY TUBE (CRT) has long been considered for use as a vehicular display device. As time has passed, however, most of the questions or objections about its use have been overcome. With the tendency towards even more highly feature-oriented automobiles in the future, a comparison between the V-CRT and other historically competitive display devices reveals the CRT as an extremely viable alternative in vehicular instrumentation.

Equations are derived which describe and relate the magnification, viewing angle and reflected illuminance of convex mirrors as used in automotive applications. The derived equations are compared to those for plane mirrors. Using these equations, the viewing angles of automotive rearview mirrors are calculated and depicted. The blind zones are defined in terms of the viewing angles, obstructions to vision, perceptibility limitations, and the lateral separation of vehicles. Various strategies for overcoming the blind zones are discussed.

This paper on single sided calipers traces the way in which experience of the difficulties in maintaining consistent performance with minimum drag for fuel economy is leading to wider use of sealed enclosed sliding systems for calipers accepting a small space penalty for the greater durability which is ensured.

A two-leading shoe air/spring operated wedge brake for heavy commercial vehicles of up to 13 tonnes static axle weight. The dual-wedge design gives a more uniform shoe-to-drum loading pattern than the conventional ‘S’ cam. An auto adjustment mechanism is incorporated which is fully enclosed and functions on the same proven principle as used in automobile rear disc brakes. Overall brake assembly weight is reduced by the use of direct mounted actuators. The brake has been adopted by major vehicle manufacturers in view of higher permissable axle weights, improved half systems and handbrake requirements in Europe.

Intelligent Vehicle/Highway Systems (IVHS), also known as Road Transport Informatics (RTI) in Europe and by names such as Vehicle Information Communication System (VICS) and Info-Mobility in Japan, are expected to comprise as much as 10 percent of vehicle costs by the year 2000. In view of the global nature of the automobile industry, global IVHS standards are required There are three particularly important areas for standardization: data communication links between vehicle systems and the infrastructure, digital map databases for the on-board navigation and driver information systems, and the driver/machine interface. This paper outlines key IVHS standards requirements and some of the efforts already underway towards their development.

The Global Powder Metallurgy Property Database was released to the general public in October 2004, with a definite focus on the automotive end user community. The Database is the culmination of four years of planning, formulating and joint development between the North American, European and Japanese powder metallurgy communities. This unique data offering includes ferrous, non-ferrous and bearing alloys and covers mechanical, physical and fatigue data. Nearly 200 different alloys are included. Materials and properties can be searched using MPIF and ISO material codes, following standard or advanced search methods with up to six variables simultaneously. Graphical presentation of the data is available throughout the system. Examples of search outputs are presented along with helpful hints for getting the most out of this new and exciting powder metallurgy database.

As companies transform themselves from national or multinational organizations into global businesses, the corporate R&D process must also be transformed. Forces driving this change include a need: to link more directly to customers and markets around the globe; to rapidly deploy product and process technologies throughout the business operations world-wide; and to remain abreast or ahead of competitors in access to technology regardless of its geographical origin. Defining an optimal global R&D organization within a company depends on accurately defining corporate objectives and needs for global R&D. Such networks can serve either to access global technology or to disseminate centrally developed corporate technology. The structure and operations will be different in the two cases. Finally, interactions between companies are becoming increasingly important.

The Goals Report together with its substantial number of supporting documents is an excellent study of engineering education as it is today and as it is likely to evolve in the next 10 to 20 years. The philosophy of its many findings and recommendations can be expressed in three broad areas of recommended change. They are: 1) Bachelor's degree programs should be liberalized. 2) Graduate work at all levels will continue to expand. 3) Continuing education of one sort or other will be the habit and expectation of most practicing engineers. Supporting these three basic concepts are many detailed analyses and recommendations. The full report is recommended reading for all engineers and the author presents the opinions of a practicing engineer with respect to the basic recommendations.

The glare to pedestrians remains one of the biggest challenges since the invention of the automobile and the automobile lighting. As far as pedestrians are concerned, whether the roadside pedestrians or the pedestrians in the crossing area are almost like lambs to the slaughter. To balance the glare interference of automobile lighting and protecting pedestrians, modeling and simulation for the pedestrian glare have been theorized by the use of forest sunlight effects and a novel controlled dark photonic channel. Based on the modeling and simulation, a novel full-factors light environment control system and pedestrian glare-free lighting system have been derived.

The catastrophic effect of oxidation of molybdenum on the electronic signal integrity of an airborne avionic system is documented. A chemical process for effective reduction of these corrosion products is defined, and fixtures are described for the electroplating of coaxial cables on aircraft without removal of the cables. An electrolytic process for plating nickel and gold over molybdenum is developed, and shown to have an excellent first pass through yield. The investigation and development of a repair process shows a unique approach to failure analysis and problem solving, and results in restoration of the original electronic performance of the coaxial cable.

Eighteen vehicles ranging from a 1938 Dodge to a 1965 Mustang were tested to determine their fuel economy and exhaust emissions relative to today's vehicles and today's driving conditions. The 1979 models are getting about 10% better fuel economy over the urban cycle and 20% better over the highway cycle than the older vehicles. The reasons for these differences as well as the exhaust emissions from the older vehicles are also discussed.