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Viewing 164191 to 164220 of 185215
1969-02-01
Technical Paper
690713
J.A. Saavedra
The current family of Air Force space launch vehicles which has grown primarily from our series of ballistic missile programs is described. Continuing evolutionary booster developments and improvements, in combination with space configured upper stages and strap-on solid motors, have provided the Air Force with this versatile family of small, medium and large launch vehicles. Growth versions of these vehicles, attained through stage and component improvements, new combinations of stages, and application of advanced technology programs, are presented. These growth versions provide the Air Force with a number of options for increased launch vehicle capabilities in the 1970's.
1969-02-01
Technical Paper
690716
W. H. SIEGFRIED, R. W. GOLDIN
Abstract Although currently available booster technology could allow a major decrease in space-booster costs, hardware already built in the Saturn system has precluded any development efforts in this direction. However, as such hardware is programmed for launches during the next several years, decisions concerning such low-cost approaches become more imminent. This paper reviews the available alternatives and describes the characteristics and capabilities of a low-cost booster system which is both desirable and practically feasible for missions beginning as early as 1973. Space program plans project needs for (1) Space-Station deployment, (2) Space-Station logistics supply, (3) unmanned scientific planetary probes, (4) further lunar exploration, and (5) large synchronous-orbit satellite deployment. These missions are interrelated in the paper with regard to booster and spacecraft capabilities.
1969-02-01
Technical Paper
690715
J. W. Sandford, J. E. Martin
The Saturn V launch vehicle and its potential derivatives are the backbone of this nation's manned space program. In the past two years, this vehicle has progressed from development into its operational phase. This paper reviews the current status of the Saturn V and discusses its possible evolution and growth to meet the requirements of missions being postulated for the next ten years. These missions include extension of the Apollo lunar-landing program to permit more extensive manned exploration, launch of space station modules in support of an ultimate space base, logistics support of early space stations, and unmanned missions to outer planets. Experience gained during operation of the Saturn V makes feasible substantial cost reductions in the production, test, and launch operations of the vehicle. Potential methods leading to a low-cost Saturn V are also reviewed in this paper.
1969-02-01
Technical Paper
690708
Roland G. Bernier
Major survivability considerations in the design of helicopters are reviewed, and the underlying philosophy of approach is presented. Identification of vulnerability problems is based on lessons learned in Vietnam.
1969-02-01
Technical Paper
690514
J. R. Hudnall, P. L Gerard, C. B. Hood, I. D. M. Burns, A. Fiedler, E. Goulley, P. Resi
Results of recent studies show that significant supplemental protection against corrosive engine wear can be achieved by selected gasoline formulations. Several approaches are shown to be possible. Antiknock scavenger formulation and control of gasoline sulfur content are potential methods. However, a practical and much more flexible method is shown to be the use of gasoline antiwear additives. Confirmation of additive antiwear performance in laboratory engines and chassis dynamometer tests is shown in the results of thousands of miles of field tests with taxicabs operated in congested city traffic, where significant reductions in rates of increase in oil consumption were observed. In addition, the value of selected additives to the motorist is established by results obtained in fleet tests conducted in consumer car service.
1969-02-01
Technical Paper
690199
Robert D. Karam, Robert J. Eby
A description of digital computer methods and numerical techniques which are used in evaluating temperature distributions in spacecraft structures is presented. The theory and application of thermal modeling from the point of view of comparing the accuracy of simplified analytical models with zonal and nodal methods are discussed, and an example is given to illustrate the general theory.
1969-02-01
Technical Paper
690202
Robert F. Greene, Richard E. Turner, Nathan D. Watson
A generalized approach used in the thermal analysis of complex orbiting spacecraft is presented. The approach, consisting of the development of a mathematical model and its refinement, using verification testing, has allowed close predictions of actual spacecraft temperatures during flight. The application of this approach in the analysis of the Injun V (Explorer 40) spacecraft is presented as an example.
1969-02-01
Technical Paper
690330
Lewis E. Herr
When the performance envelope for the pressurized Navajo was finalized, it was apparent that a sophisticated environmental system was needed to guarantee passenger comfort. The environmental studies centered around the ventilation, pressurization, heating, and air cooling systems. This paper discusses parameters that governed the selection of each system design, and how they were intergrated into a proper functioning overall system. The hardware that was needed together with those factors that govern their selection are also discussed. Development of the various systems imposed many problems and the solution to these problems required many changes. Some of the more important of these are described in detail.
1969-02-01
Technical Paper
690623
Leslie D. Calhoun
The principal objective of the Apollo Applications Program (AAP) is to keep astronauts in space for extended periods of time. This paper reviews the Environmental and Temperature Control Systems needed to support the men in space for periods up to eight months. The ECS must pressurize the various stages with mixed gas atmosphere, control oxygen pressure, remove carbon dioxide, and provide cooling for astronauts wearing liquid cooled garments. The TCS features a bifillar radiator for flow stability, electrical wall heaters for warmth, and thermal curtains to minimize heat loss. The functions performed by ECS and TCS, and the operating systems which perform these functions, are described in depth.
1969-02-01
Technical Paper
690622
Joseph C. Cody
The approach used to integrate the thermal and life support systems of several large spacecraft is presented. These spacecraft will be assembled in earth orbit to make up the Apollo Applications Program (AAP) Orbital Assembly (OA). Due to the size of the spacecraft and the complexity of the systems involved, it was necessary to analyze the thermal and life support systems by defining appropriate interfaces and integrating the results into overall system math models.
1969-02-01
Technical Paper
690643
F. H. Schubert
TRW, under NASA sponsorship, has developed a water electrolysis module (WEM) designed to provide 3.6 lb/day of oxygen at a current density of 100 amps/sq ft and at a pressure level of 80 psia. Although designed for aircraft application, the concepts employed in the design of the module make its use in other life support systems possible. One of the ten-cell water electrolysis modules fabricated, and designated as WEM No. 1, has been successfully operated for 7525 hr. These hours consist of 300 hr of parametric, 180 hr of cyclic, and 7045 hr of endurance testing, to date. The endurance test program is being conducted at a current density of 80 amps/sq ft, a temperature of 175 F, and a pressure level of 30 psia. This paper describes the cell and module configurations and the materials of construction selected. Results of the parametric and cyclic test programs are presented and cell performance and servicing and maintenance requirements discussed.
1969-02-01
Technical Paper
690618
Frank H. Samonski, James M. Ross, Henry Nicolello
The significant problems encountered in the development of the environmental control system for the command and service modules of the Apollo spacecraft are described in this paper. Three problem areas and the solutions are discussed in detail: corrosion in the coldplates, deficiencies in the heat-rejection capability of the space radiator, and performance defects in the evaporator. A summary of the constraints imposed upon the environmental control system designer because of spacecraft and mission considerations is given. Also, a brief explanation of the environmental control system and its functions is included.
1969-02-01
Technical Paper
690644
Bert Cooper, J. V. Wagner
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.
1969-02-01
Technical Paper
690626
Joseph B. Gillerman
A regenerative carbon dioxide removal system being developed for spacecraft life support systems comprises two molecular sieve canisters. The canisters operate in cycles and maintain the carbon dioxide percentage within required levels for a three-man crew over a minimum period of 28 days before regeneration is required. Unlike the expendable chemical removal techniques used for Gemini and Apollo, the cyclic, nonexpendable adsorption system can meet, with a minimum weight penalty, the carbon dioxide removal requirements of extended space flights planned in the future.
1969-02-01
Technical Paper
690637
John B. Hall
Life support systems to support multiman crews on extended space missions will require the development of regenerative systems more advanced than those presently available. This equipment must be maintainable, highly reliable, and possess automatic features to enhance mission success. Presently at the NASA Langley Research Center, a program is underway to provide the technology for such systems. The status of the program is presented which includes a discussion of the Integrated Life Support System (ILSS) now in-house, plans for the development of advanced subsystems, and a summary of the Advanced Integrated Life Support Systems (AILSS) program to provide maintainable subsystems integrated into a multicompartment chamber.
1969-02-01
Technical Paper
690640
R. G. Huebscher, A. D. Babinsky
Abstract The carbonation cell system is an electrochemical system which concentrates and separates carbon dioxide from an enclosed environment. Areas of application include spacecraft, submarines, and aircraft employing closed-loop oxygen rebreather systems. Concentration and separation of the carbon dioxide are performed in two stages; Stage I is the concentrating stage using an alkaline electrolyte and Stage II, which uses an acid electrolyte, accomplishes separation of oxygen from the carbon dioxide. The effluent oxygen is returned to the enclosed environment and the carbon dioxide supplied to a reduction system or vented overboard. This paper describes the research and development toward the design of a four-man prototype system. Initial feasibility tests are summarized and results from endurance tests in excess of 2000 hours on the individual system stages are discussed. A comparison with other carbon dioxide removal systems is included.
1969-02-01
Technical Paper
690638
C. G. Saunders
A number of zero-gravity liquid-gas phase separators such as rotating units, elbow type units, porous plate, and the hydrophobic-hydraulic type discussed in this paper are presently being developed for spacecraft use. The basic theory of this unit is presented and the application of surface tension phenomenon is discussed as they apply to the design. The materials of construction are covered, and the ultimate use on Apollo 11 is described.
1969-02-01
Magazine
1969-02-01
Technical Paper
690579
Allen O. Elkins, Henry W. Schaefer, Dwight M. Brooks
A review of the U. S. Army concept for development of a Family of Military Engineer Construction Equipment (FAMECE) in light of basic problems facing the military engineer is presented. Problems evaluated are air and ground mobility, increased productivity, maintenance of unit integrity, and standardization of unit design. Although in the past the military attempted to develop lightweight, compact equipment which could be disassembled, such equipment did not perform to operational standards under field conditions. This led, however, to the FAMECE concept of a power module being utilized with a wide variety of work moduli. It addresses the problems of mobility, standardization, and logistics. At present, the program is well along in terms of conceptual design and is backed by several years of research and development efforts.
1969-02-01
Technical Paper
690569
G. L Klose
Widening horizons on the social implications of engineering activity are creating new demands on technology. One of the demands on construction vehicle engineering groups is that operators be given reasonable protection against crushing should the vehicle roll over. In this paper the history of such structures is reviewed, basic design considerations are emphasized, and possible evaluation methods are presented.
1969-02-01
Technical Paper
690268
R. N. Reddy, D. D. Sen, M. S. Keshav
Multiplate clutches are often designed without considering the effect of spline friction and the friction coefficient velocity characteristic of the friction linings. Such designs give an underrated clutch for a given torque duty. An attempt is made in this paper to clarify the factors that must be considered in the clutch design.
1969-02-01
Technical Paper
690054
William J. Evans
Resistance spot welding, projection welding, and drawn arc stud welding, are discussed as processes for the attachment of welded fasteners. Recent development work in the drawn arc stud welding process is emphasized. The drawn arc stud welding process offers the greatest flexibility of fastener design with minimal heat affected zone problems.
1969-02-01
Technical Paper
690372
C. G. A. Rosen
Although engineering handbooks represent an achievement in cooperative problem solving, an engineer cannot rely on handbooks alone to define causes. Essential to locating the grounds for a solution is a combination of technical and nontechnical abilities. A sharpened sense of analysis, reliance on experience as well as training, and conscious effort to be creative are needed.
1969-02-01
Technical Paper
690347
Roy F. Abell
A state-of-the-art presentation of how and why a hydraulic valve lifter works in a modern automotive engine. Requirements for a successful hydraulic valve lifter application are discussed. Service considerations to be kept in mind when using hydraulic lifters are reviewed.
1969-02-01
Technical Paper
690303
P. S. Myers
1969-02-01
Technical Paper
690349
A. B. Sarkis
This paper describes a new approach to the development of a superior engine oil specifically designed to give outstanding performance in mixed-fleets powered by today’s modern diesel and gasoline engines, under a wide variety of applications and service conditions. This unique design was achieved by a 10-point program, which started with a study of critical equipment requirements and oil performances in the field and duplicated them in the laboratory to screen experimental formulations. The paper outlines the additive building blocks and their functions, as well as the specification engine tests which were utilized to screen candidate formulations. It then goes on to describe the extensive controlled and documentation field tests utilized to verify that the selected candidate does indeed meet the stringent targets outlined at the initiation of the development program.
1969-02-01
Technical Paper
690348
E. M. Smoley, F. J. Kessler
A compressible gasket composition appears to exhibit a critical strain for a compressive strength failure. The strain is defined from plots of stress or strain versus weight density of the gasket in the state of compression. A method is suggested for measuring the critical strain in joint assemblies exposed to a service environment. Also mentioned is the relationship of the strain to the stress, time, temperature conditions required for a strength failure. A flange test is pointed out as an approach to evaluating strength for elastomeric gaskets. Practical design guides are listed for increasing the resistance of nonmetallic gaskets to strength failures in flanged joint assemblies.
1969-02-01
Technical Paper
690792
E. Berry Sanders
This paper discusses the application of hydraulic pumps which are driven through belts and electric clutches and applied in the engine compartment of highway type trucks.
1969-02-01
Technical Paper
690794
W. E. Woollenweber, J. R. Harper
The 3TC Turboconveyor* discussed in this paper is a new product developed to provide a simple, low cost source of compressed air for the unloading of bulk commodities and is the first unit specifically designed to accommodate all conditions peculiar to pneumatic conveying operations utilizing the exhaust gases of the diesel engine as a source of power. The heart of the conveying system, a small, efficient, highspeed turbine driven centrifugal compressor, is described in detail.
1969-02-01
Technical Paper
690793
Richard Chaltry
There is a growing demand today for design improvement in the operation of auxiliary functions on both off-highway and on-highway mobile type equipment. Faster, more efficient operation, better control, and less operator fatigue were the design goals considered in the design of the new AU air pump described in this article. Using the available pneumatic power source presently incorporated in the design of most vehicles today, this efficient, light-weight, low-cost, high-cycling speed intensifier is limited in its application only by the imagination of the vehicle designer.

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