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Pilots' use of the traffic alert and collision avoidance system (TCAS II) was evaluated in simulated air carrier line operations. Sixteen three-person airline flight crews currently flying the Boeing 727 served as subjects. Each crew flew eight flights with or without TCAS as part of the full-mission simulation. Their performance of the avoidance maneuvers and evaluation of the system were measured. The crews were trained on the aircraft differences and the TCAS II. The second day consisted of a 10 hour duty day of normal line operations. All communications, navigation, and cockpit procedures were carried out according to the standards of their particular airline. The crews were under full air traffic control along with the other aircraft in the airspace. All crews were exposed to the same traffic conflicts under the same conditions of high/low traffic densities, high/low workload, high/low visibility. Pilot flying and dusk/night lighting were counterbalanced.

Gear surface fatigue endurance tests were conducted on two groups of 10 gears each of carburized and hardened AISI 9310 spur gears manufactured from the same heat of material. Both groups were manufactured with standard ground tooth surfaces. The second group was subjected to an additional shot-peening process on the gear tooth surfaces and root radius to produce a residual surface compressive stress. The gear pitch diameter was B.89 em (3.S in.). Test conditions were a gear temperature of 350 K (170 °F). a maximum Hertz stress of 1.71×l09 N/m2 (248000 psi). and a speed of 10 000 rpm. The shot-peened gears exhibited pitting fatigue lives 1.6 times the life of the standard gears without shot peening. Residual stress measurements and analysis indicate that the longer fatigue life is the result of the higher compressive stress produced by the shot peening.

A series of studies at the General Motors Research Laboratories have demonstrated the practical benefits of constructing automotive structures as three dimensional space frames with attached panels. Importantly, a metallic space frame with a plastic skin has been shown to be a highly weight-efficient passenger car structure.

The major US helicopter manufacturers were asked to support a study by the FAA to design a total FAA system for the year 2000 and beyond. Bell Helicopter Textron chaired a VSTOL committee which collectively prepared and presented the desires of the vertical lift community. A requirement was noted for the necessary infrastructure including vertiports with appropriate landing aids. The integration of emergency medical service into the system was also recommended. Some operational improvements were noted utilizing rapid computational techniques for both ground and airborne systems to reduce separation and permit joint usage of existing facilities under separate rules, maintaining at least the present level of safety. The automation of cockpits using simplified controls and advanced presentation methods to provide the pilot with similar cues under restricted visibility to those available in the real world was also suggested.

It is highly probable that the advanced air transport aircraft which will become available early in the next century will be hydrogen fueled. The use of hydrogen fuel will require designers, production personnel and aircraft operators to positively assure fuel system integrity. The safety, reliability, maintainability and quality assurance specialists in the manufacturers' organizations and in the operating air carrier organizations will be faced with unique problems in achieving fuel system integrity and assuring it throughout the operational life of the aircraft. The reasons why the use of hydrogen fuel in transport aircraft seems inevitable and some of the safety and quality problems which may be encountered, with some possible solutions, are described in this paper.

Rolls-Royce Civil Engine strategy calls for technology development for derivative engine programs and application to longer term new propulsion concepts. In the near future, further development of the turbofan for the next generation of derivative aircraft is planned. Reductions in fuel consumption, noise, weight, and cost will be achieved with engine cycles in the range currently in service and by refinements to component efficiency and application of advanced materials and manufacturing techniques. This derivative approach is likely to continue until the relationship between first and operating cost changes dramatically. As fuel prices rise, or the demand for more rapid travel develops, changes to the basic engine cycle will be necessary. For long range, high subsonic speed operation, substantial increases in turbofan bypass ratio will be needed to realize further fuel burn reductions.

On the Thermodynamic Spectrum of Airbreathing Propulsion - Insights from 1958 are valid guidelines yet in 1988 - Paul Czysz. Staff Manager, McDonnell Douglas Fellow. McDonnell Douglas Corporation

Sustained high speed flight cannot be achieved by improvements in traditional turbojet/turbofan propulsion systems. Instead, propulsion cycles optimized for high speed flight are required. These include combined cycles such as the air turboramjet for the lower speed regime, and scramjet-type cycles for the higher speed regime. Characteristics of these advanced airbreathing propulsion cycles are discussed, and propulsion-related technology issues are addressed.

Since 1982 Daimler-Benz is the first commercial vehicle and bus manufacturer to offer modern anti-lock systems (ABS). After several years of development, anti-lock systems have technically matured to be installed upon request in vehicles with air brakes. The installation rate of this safety item has been steadily increasing ever since. The fundamental design and control philosophy of 4- and 6-channel anti-lock systems will be described. Besides a global analysis regarding the failsafe quotas of digitized electronics in road vehicles, the ABS-specific components will be looked at. The gain of safety achieved by the installation of ABS in commercial vehicles and buses will be presented with the aid of computer simulation. A 40-t-truck/trailer combination, with ABS, without ABS and with a partially defect system, will serve as an example to demonstrate the dynamic behavior during “Braking in a Straight Line” and “Braking in a Turn”

NASA has determined by experimental and analytical effort that use of advanced turboprop propulsion instead of the conventional turbofans in the older narrow-body airline fleet could reduce fuel consumption for this type of aircraft by up to 50 percent. In cooperation with industry, NASA has defined and implemented an Advanced Turboprop (ATP) program to develop and validate the technology required for these new high-speed, multibladed, thin, swept propeller concepts. This paper presents an overview of the analysis, model-scale test, and large-scale flight test elements of the program together with preliminary test results, as available.

Future on-board navigation and information systems for automobiles will automatically keep the driver informed of current location, deduce best routes to specified destinations taking into account current traffic and road conditions, and provide turn-by-turn route guidance according to where the automobile is along the route. Other road transport informatics functions will include location-keyed directory services and automatic vehicle identification for toll and parking billing. These systems will be integrated with systems for automatic headway control and collision avoidance and, eventually, automatic vehicle control. Advanced on-board information systems require integration of vehicular navigation technologies such as dead reckoning, proximity beacons, and radiolocation with various other technologies including digital cartography, data processing and storage, mobile data comunications, information display, voice synthesis, etc.

Joining advanced composite materials is one of the greatest obstacles to proliferating their use in aerospace structures. Another hindrance is the high cost of manufacturing advanced composite structures using conventional methods. The present trend in both the automotive and aerospace industries is lighter weight, energy efficient structures. In the aerospace community, the use of advanced composite structures has the potential for weight reductions of 35 to 40 percent as compared with the use of conventional aluminum alloys. However, this advantage is offset by the higher cost of manufacturing in using conventional composite technology. This paper identifies pultrusion and induction bonding as potential methods for manufacturing lightweight high-strength advanced composite structures.

Recovery of oxygen (O2) from water will be needed on future long-duration manned space missions. Direct electrolysis of cabin water vapor into O2 and hydrogen (H2) offers the advantage of avoiding the phase change, separation and handling of liquid water in zero gravity. These considerations affect liquid electrolysis subsystems which are presently baselined for central O2 generation aboard the Space Station. This paper presents the results of a technology development program that Life Systems, Inc., in cooperation with the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) has been undertaking. The goal of the program is to develop Water Vapor Electrolysis (WVE) hardware that can selectively be used as localized topping capability in areas of high metabolic activity without oversizing the central Air Revitalization System (ARS).

The direct electrochemical reduction of carbon dioxide (CO2) is achieved without catalysts and at sufficiently high temperatures to avoid carbon formation. The tubular electrolysis cell consists of thin layers of anode, electrolyte, cathode and cell interconnection. The electrolyte is made from yttria-stabilized zirconia which is an oxygen ion conductor at elevated temperatures. Anode and cell interconnection materials are complex oxides and are electronic conductors. The cathode material is a composite metal-ceramic structure. Cell performance characteristics have been determined using varying feed gas compositions and degrees of electrochemical decomposition. Cell test data are used to project the performance of a three-person CO2-electrolysis breadboard system.

This paper presents the design and the test results of a regenerative carbon dioxide control system, using solid ion exchange materials. The system applies a two bed approach with regeneration by steam and is designed far a 3 man operation. Two adsorber materials were investigated and applied throughout the tests. The system contains an evaporator, two adsorber beds, a condensing heat exchanger and an electronic controller. Test results concern the major performance parameters like CO2-loading, pressure loss, moisture range, stability ranges and energy required for dessorption. Furthermore, material dedicated analysis has been performed regarding offgassing products during operation.

The scenarios of Environmental Control and Life Support Systems (ECLSS) which will be necessary within the next sixty years are outlined. From this the need for technologies are derived and condensed in a programme plan. Technologies necessary for the Columbus Initial Operating Configuration (IOC) are already under development. The status of this programme which includes the development of regenerative CO2-control, condensing heat exchanger, contamination control and monitoring and a low noise variable speed fan is described. The areas where the technological development should start immediately are discussed.

An onboard simultaneous measuring method of solar absorptance αS and total hemispherical emittance εH for thermal control materials is proposed. This method allows to determine αS and εH simultaneously by giving different levels of input power to a sheet heater attached to the sample, and there is no need to use the values of the mass or the specific heat of the sample materials for the data reduction. In order to verify this method on the ground, the parameters αS and εH are measured for three kinds of thermal control materials.

This paper provides a description of the current European Space Suit System (ESSS) status. The ESSS is foreseen for servicing of various elements of space infrastructure within typical operational scenarios based on Hermes. As a result of different EVA studies the ESSS concept has been defined and structured in three modules: the EVA Suit Enclosure Module (ESEM), the EVA Life Support Module (ELSM), and the EVA Information and Communication Module (EICM). The main portion of the description herein is provided for the ELSM, since this module has been studied in more detail up to now (ESA contract) in comparison with the ESEM and the EICM.

There currently exist three practical processes for reduction of carbon dioxide in manned spacecraft environmental control and life support systems. The Sabatier (SCRS) and the Bosch (BCRS) Carbon Dioxide Reduction Subsystems are well known, while the Advanced Carbon Dioxide Reduction Subsystem (ACRS) is more recently developed. In this paper, the physiochemical fundamentals, developmental history, and reactor hardware implementation of these three processes are described. The methodology, data, and results of a logistics trade study of these carbon dioxide reduction processes for manned space mission application are presented and discussed.

It is necessary to remove carbon dioxide (CO2) and other contaminant gases generated from the crew and nonmetallic materials to keep the allowable level of them for the long duration life support in the space station. Therefore, the Air Revitalization System (ARS) shall be provided in the space station. The ARS for Japanese Experiment Module (JEM) consists of a regenerative CO2 removal system and a trace contaminant control system (TCCS). A solid amine CO2 removal system has been evaluated as the preferable technology. An adsorption and catalytic oxidizing method has been selected for the TCCS. This paper describes the outline of the investigations and study results of the ARS for JEM implemented on the phase B preliminary study (entrusted by NASDA) and subsequent activity.