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NEW WELDING processes are dropping costs while providing improvements in weld quality. This paper describes some of the more promising new developments in pressure and fusion welding and brazing. Included in the discussion are ultrasonic, high frequency resistance, foil seam, magnetic force, percussion, friction, and thermopressure welding and diffusion bonding. The description of adhesive bonding includes the development of glass or ceramic materials as structural adhesives.*

The likelihood of transmission of potential disease agents between animals and man during spaceflight is a real concern. Development of disease exclusion lists for animals and refinement of animal containment units have been the principal means of providing protection to the crew members. Awareness of potential latent infections and a judicious use of the higher risk category of animals such as wild-caught nonhuman primates provides another level of protection. Use of high efficiency filters, gasketing, and differential air pressures have all enabled increasing levels of safety through containment of potential aerosol escape from animal habitats.

This paper describes the testing of a waste management system designed and fabricated for use in a space vehicle. The system provides for the collection and inactivation of urine, feces, emergency diarrheal disorders, vomitus, and debris; the volumetric determination of each micturition; and onboard storage of the inactivated wastes within the waste management system compartment. The zero-gravity test program conducted in a KC-135 aircraft provided the primary verification of the performance of the waste collection and urine volume determination functions prior to actual space flight. The test hardware simulated the actual system to a high degree of fidelity with respect to operational characteristics of the airflow required in collection, mechanical functions and system pressure differentials, in order to minimize simulation errors.

For human beings who have been reared on the earth with its 1 G gravitational field, the condition of weightlessness is a world with which we are unfamiliar. Even if the layout and equipment configuration of a spacecraft designed to compensate for operation under Zero-G conditions, there are some things which are not effective under actual weightless conditions. In the design of a manned spacecraft, it is necessary to accumulate design data on human performance in a weightless condition, then to undertake design evaluations and verification under weightless conditions. In this paper, testing for the purpose of evaluating the effectiveness of Zero-G simulation using neutral buoyancy, conducted first of all in Japan, and recommendations on the equipment and Facilities required to conduct such simulations, are described.

This paper investigates the use of several zero-ozone depleting potential (zero-ODP) HFC refrigerants, including HFC-134a, HFC-227ca, HFC-227ea, HFC-236ea, HFC-236cb, HFC-236fa, HFC-245cb, and HFC-254cb, for centrifugal chiller applications. We took into account the thermodynamic properties of the refrigerant and aerodynamic characteristics of the impeller compression process in this evaluation.. For a given operating temperature lift, there are significant differences in the pressure ratio required by each refrigerant and this variation in pressure ratio directly affects compressor size, efficiency, and performance. A comparison of the HFC refrigerant candidates with CFC-114 shows that HFC-236ea, HFC-227ca and HFC-227ea are viable alternatives for centrifugal water chillers. HFC-236ea has properties closest to CFC-114, and will result in comparible performance, but will require a slightly larger impeller and a purge system.

Design load values are a prime consideration in space suit design. Pressurized garment assemblies can be accurately modeled as a cylindrical shell under pressure to determine the resulting pressure loads. But, the resulting longitudinal loads are not a complete picture of the load environment. The man induced loads generally act longitudinally and are very often the larger loads the space suit restraint system must withstand. This paper presents the data collected to fill out the human strength data base in the glove area along with a short description of how this data was collected. Also, a description of how this data was used in the design and flight certification of the current Shuttle Extravehicular Mobility Unit space suit is included along with a discussion of techniques to extend this model to include future space suit design.

The development of the XB-70 research aircraft produced advancements in many fields of technology. This paper covers a few of these advancements in the areas of materials, equipment, and manufacturing. These include honeycomb construction, PH 15-7 alloy steel, vacuum melted H-11 steel, equipment capable of withstanding high temperatures, chemical milling of many different alloys, miniaturized welding equipment, and exothermic brazing techniques.

Planning for ground servicing and maintenance started in the proposal phase and has been followed by test program experience with the XB-70 Mach 3 air vehicle. Servicing and associated safety requirements are summarized. Discussion of maintenance and support actions includes mention of equipment provided to meet the requirements. Preflight, postflight, and periodic operations are outlined, along with some indication of changes that resulted when plans were put into practice. The demands of a high performance flight test air vehicle limit movements toward simplification.

A non-destructive x-ray technique, the double crystal diffractometer method, is presented as a tool to investigate the aging and deformation behavior of the Al-Li alloy. This is a sensitive method for measuring the strain and dislocation density within individual grains through the x-ray rocking curve. In addition, models were developed to describe the aging and deformation characteristics of this alloy.

X-ray is an indispensable aid in locating and determining the extent of incipient failures in structure which is inaccessible by position or covered by multiple layers of metal. It is also the most feasible method for checking oil coolers for contamination; bonded honeycomb panels for water; fuel lines for erosion; and with a 360 deg emission tube, fuselage frames for structural integrity without removing the interior upholstery and panels from the passenger compartment or cargo compartments.

This SAE Aerospace Standard (AS) covers 6-point and 12-point flare nut crowfoot, flare nut wrenches, double end flare nut wrenches, combination box end and flare nut wrenches, combination open end and flare nut wrenches, and ratcheting flare nut wrenches that are designed with the following requirements: (a) non-distorting usage; (b) possessing the strength, clearances, and internal wrenching design to be used on hydraulic tube fittings that conform to the requirements of SAE J514 and ISO 8434-2; and (c) transmitting torque to tube fittings without bearing on the apex of fitting wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

This SAE Aerospace Standard (AS) covers high strength thin wall (commercial) sockets, universal sockets, box wrenches and torque adaptors which possess the strength, clearances, and internal wrenching design so configured that, when mated with bi-hexagonal fasteners conforming to the requirements of AS870 for inch sizes and ISO 4095 for metric sizes, they shall transmit torque to the fastener without bearing on the outer 5% of the fastener's wrenching points. Inclusion of dimensional data in this document is not intended to imply that all the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes. The dimensional limits of box and combination wrench lengths have been established to provide configuration control for tool storage applications.

This SAE Aerospace Standard (AS) covers adjustable and non-adjustable spanner wrenches generally used for aerospace machinery maintenance and for tightening and loosening hose couplings and hydrant caps. Inclusion of dimensional data in this document is not intended to imply all of the products described therein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

Cockpits have changed dramatically over the last ten years. The electro-mechanical instruments have largely been replaced with electro-optical controls and displays. This change in the pilot-vehicle interface, coupled with a second development, the emergence of a very powerful airborne computer system, an Electronic Crewmember, has had a significant impact on workload in the cockpit. Workload has shifted from physical to mental, and many workload measurement tools applied previously may no longer be appropriate. This paper discusses the prediction, real time measurement and dynamic allocation of cockpit workload in an aircraft with a crew of two -- one human and one electronic.

One of the most unsolved problems in space projects, where human beings are involved, is the impossibility of simulating on the ground the effects of microgravity on astronauts' operability in space. [1] In particular, this is traceable in the performance of work activities, such as performing physiological scientific experiments. [2] This paper focuses on a study of the gap between the two operational scenarios: the ground test simulation and the in-flight space performance of complex physiological experiments. The major differences between the two operational scenarios are highlighted, and recommendations for improvement are suggested. The main finding of this paper is that, in order to make experiment performance not only possible but also easy and efficient, it is necessary to consider all human factors involved. With this perspective, the author's aim has been to find an effective way to consider all human factors of the ground and space operational conditions.