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Viewing 164461 to 164490 of 185187
1969-02-01
Technical Paper
690722
L. J. Adams, R. E. Dreith
An evaluation process that has been used successfully on past programs to assess technical performance is described. The factors to be considered in selecting parameters to be monitored, the assignment of responsibility to meet performance requirements, the methods of evaluating performance, the reporting systems, the methods of problem identification and resolution, and the outlook for future evaluation systems are discussed.
1969-02-01
Technical Paper
690725
L. P. Pipes, E. G. Perry
This paper discusses a new concept for remotely entering manufacturing planning data into a computer system. By standardizing planning operations and using “on line” questioning techniques, the volume of paper generated manually is reduced, time spans for original and change planning for fabricated parts is shortened, errors are decreased and subsequent engineering changes are implented faster.
1969-02-01
Technical Paper
690744
R. P. Lambeck
An increase in pump drive speeds is desirable in order to minimize pump size and weight. This paper reviews the relationship between pump speed and power loss, as well as some of the mechanical limitations encountered at higher speeds. It also discusses the trade-offs available involving weight, performance and life. The effects of temperature and fluid selection are included.
1969-02-01
Technical Paper
690741
Frank J. Jandrasi
In designing a system, the systems engineer must thoroughly understand the requirements, constraints, and values established by the customer, must plan and schedule a program to satisfy these conditions, while also considering cost, reliability, and maintainability. Using an APU system as an example, the author traces the development of a design for a control system. First the control system is evaluated as to requirements, constraints, reliability, cost, and maintenance. A preliminary design is developed after conducting various studies, and a detail design implemented. Data obtained from system simulation aid in the development pattern of the control system. The development of the component and subsystem is also initiated, with the system development an extension of this work. The staffing and management of such a program are discussed.
1969-02-01
Technical Paper
690761
John Thomas
The National Traffic and Motor Vehicle Safety Act of 1966 imposed new responsibilities on manufacturers of commercial motor vehicles, on truck body and equipment manufacturers, and on dealers and distributors who offer these vehicles or equipment for resale. Applicable Federal Motor Vehicle Safety Standards are charted, and responsibility for compliance and certification as divided between the original vehicle manufacturer and subsequent dealers and distributors is discussed.
1969-02-01
Technical Paper
690763
F. D. Griffith
Development of emission control systems for a complete line of heavy-truck gasoline engines is presented in this paper. Experience gained in emission control programs for engines used in light-duty vehicles proved beneficial in establishing basic guidelines for heavy-truck program. Various engine modifications, primarily concerned with induction systems and combustion chambers, provided sufficient emission reduction to meet 1969 California and 1970 Federal standards. Secondary air injection into exhaust was not required. Durability tests required for certification indicated the necessity of adhering to recommended service procedures to maintain low emission levels.
1969-02-01
Technical Paper
690759
J. L. Keller, H. T. Niles, H. A. Bigley
This paper reports the results of a series of vapor lock road tests on 26 cars (1966 models), half of which were equipped with exhaust emission control systems. The objectives of the tests were to determine the effect of emission controls on vapor locking tendencies, to study effects of fuel volatility and operating conditions on fuel system temperatures, and to study correlation of these temperatures with temperature versus vapor/liquid ratio characteristics of fuels. The data obtained show no significant difference in vapor locking tendency between the emission control equipped and nonequipped cars as groups, though significant differences are shown for some individual car pairs. An analysis is presented of the relation between fuel volatility, pump temperature during acceleration, and the onset of vapor lock.
1969-02-01
Technical Paper
690762
Berkley C. Sweet
A summary of the effects of Public Law 89–563 -- The National Traffic and Motor Vehicle Act -- on the Truck Body and Equipment Industry in relationship to the manufacturer and/or distribution of “multistage” manufactured vehicles.
1969-02-01
Technical Paper
690765
John A. Maga, G. C. Hass
From the initial motor vehicle emission standards that pertained only to exhaust of hydrocarbons and carbon monoxide, the California laws have gradually expanded control of all types of pollution from automobiles. Whereas pioneer legislation applied to all types of vehicles, significant changes in the laws now set up separate standards for light and heavy duty vehicles and for engines using gasoline and diesel fuels. This paper reviews the history and status of present California and federal emissions standards for heavy duty vehicles and discusses possible future development in this particular vehicle class.
1969-02-01
Technical Paper
690764
Robert W. Olsen, Karl J. Springer
Exhaust emissions from heavy duty gasoline-powered vehicles have been studied in detail, under NAPCA support, at South west Research Institute. The principal exhaust emissions studied were carbon monoxide, hydrocarbons, and oxides of nitrogen. A broad variety of vehicles was tested with three variable speed experimental procedures using chassis dynamometers to simulate actual road operations. Approximately 150 trucks and buses of all weight classes were investigated to determine the ability of each vehicle to perform with the respective experimental cycle, each vehicle’s contribution of contaminants on a mass basis per mile driven, and the applicability of these cyclic test procedures for federal testing.
1969-02-01
Technical Paper
690775
B. W. Turnquest, P. G. Culliney, R. J. Danehy, R. D. Fullman
A pin and disc machine has been modified for the evaluation of silver-steel lubrication characteristics of railroad diesel oils. Use of silver pins on polished steel discs at selected loads and rubbing speeds allows good correlation with known engine behavior. In comparison with wear and friction data obtained by the four ball method, this pin and disc test gives better correlation with engine tests than the Modified Four Ball Test.
1969-02-01
Technical Paper
690772
G. G. Lewis
Oil well wireline services impose special requirements on truck chassis. Present designs are not adequate in all respects to meet these requirements. New designs are needed, particularly in view of the current trends to drill for oil in more remote areas and under severe climatic conditions.
1969-02-01
Technical Paper
690689
Earl R. Thompson, Frederick D. George
Unidirectionally solidified eutectics offer a favorable approach for producing high strength multiphase materials where one phase serves as the matrix and the other phase or phases serve as the reinforcement. In addition to high strengths, these composite materials generally exhibit excellent microstructural stability at elevated temperature. As a representative of the class of materials that shall be referred to as eutectic superalloys, the mechanical characteristics of the Ni3Al-Ni3Cb eutectic are discussed and compared with commercially available superalloys. The thermal expansion and oxidation behavior of this alloy are also discussed. The microstructure of this material is lamellar in nature and consists of approximately 44 vol % of the reinforcing phase Ni3Cb in a matrix of Ni3Al. Its melting temperature is 1280 C (2335 F), the eutectic composition is 68 wt % Ni3Cb, and its density is approximately 8.5 gm/cc (0.3 lb/cu in.).
1969-02-01
Technical Paper
690680
R. A. Sipe, W. A. Jennings
This paper discusses fabrication results experienced with HY-140 steel flight type pressure vessels. HY-140 steel is a recently developed quenched and tempered alloy (5Ni-CR-Mo-V) structural steel with a yield strength of 140,000 psi. Fabrication techniques applied, the tooling used, and the problems encountered are described in detail.
1969-02-01
Technical Paper
690690
Nelson G. Freeman, Peter B. Teets
Abstract This paper discusses the development and characteristics of a new digital flight control system (DFCS) being used in the Titan IIIC space launch vehicle. In this system, flight equations for the boost phases and coasting phases are time-shared with guidance equations in a new, general-purpose digital computer. Special software has been incorporated in the DFCS so that it can be used for a broad spectrum of mission and payloads. In addition, malfunction-detection and correction logic has been incorporated into the software for improved mission reliability. The paper describes the special tools and techniques used in developing the DFCS software; it discusses some of the solutions to development problems concerned with digital filter accuracy, environmental noise susceptibility, and bending mode foldover; and it presents flight-test results.
1969-02-01
Technical Paper
690693
John F. Garren, James R. Kelly, Robert W. Sommer
The inability of available situation displays to provide a decelerating instrument approach capability to a hover led to a flight research program in which control-command information was displayed for three degrees of freedom. The test aircraft (NASA's CH-46C in-flight simulator) was stabilized with high-gain attitude command system. Using this system, the pilot was able to decelerate the aircraft to a hover while simultaneously following a 6 deg glidepath. Although these tests demonstrate the potential of this concept, a number of factors, including adequate integration of command and situation information, were identified as affecting pilot acceptance of the system.
1969-02-01
Technical Paper
690696
Boris G. Palarz
Evaluation of design parameters for VTOL fixed wing aircraft are simplified and speeded up by the use of this digital variable stability system. This paper details the extensive preparation for developing the overall system and explains how and why the various subsystems were chosen. These development processes reflect guide lines for successful VTOL design practices, besides providing a truly flexible and complete system that allows various testing techniques to be devised so as to obtain meaningful and repeatable data.
1969-02-01
Technical Paper
690694
Robert A. Bondurant, John H. Kearns
The capability of V/STOL aircraft (including helicopters) to fly an assortment of approach and landing flight profiles dictated the need for a display that presents pilot situation information in the vertical plane. This paper describes the development of a display system known as the Flight Profile Indicator (FPI) designed to provide this information in a manner analogous to that of the USAF Horizontal Situation Indicator (HSI). The FPI is a cathode ray tube (CRT) device that displays the geometrical relationship between the parameters necessary to determine the aircraft situation in the vertical plane. The significant advantage of the FPI is that it minimizes the pilot's need to interpret various kinds of vertical situation information presently available on aircraft instrument panels and provides a more rapid, accurate, and easier assessment of the aircraft status and flight progress in the vertical plane.
1969-02-01
Technical Paper
690702
W. Cohen, R. A. Wasel
This paper discusses the technologies of solid rocket components and the effects of cost consciousness on the state-of-the-art. Motor case technology has developed steels which do not require quench-temper heat treatment and have high flaw tolerance, thus providing major cost optimizing opportunities. Nozzle technology for large solid motors is surprisingly good and accumulating knowledge points to appreciably cheaper nozzles made of prosaic materials being developed in the future. Other areas reviewed in terms of cost appraisal are the case insulation, steering systems, and propellant and processing techniques. In conclusion, possible applications for solid motors, either as prototype systems such as Titan III or intermediate type launch vehicles combining the solid booster first stage with a liquid fueled second stage for low earth orbit or lunar probes are outlined.
1969-02-01
Technical Paper
690701
Anton Dobler, Harry Koenigsberg, David Van Winkle
Soviet aerospace systems production capability has progressed rapidly during the past 15 years through sustained, intensive manufacturing technology research. Accomplishments and programs in forging, extrusion, metal working and metal joining technology are generally as advanced as those of the west. In forging and extrusion press construction, electro discharge machining, ultrasonic machining, glue welding, pulsed arc, magnetic arc and electroslag welding Soviet technology excels and is in advance of Western technology. Development programs are underway to continue to advance the state of the art for conventional as well as high temperature structural application. Combined with demonstrated characteristics of ingenuity, innovation, and originality of approach a high potential exists for future achievement.
1969-02-01
Technical Paper
690703
William R. Lucas, Rondal G. Crawford
Large launch vehicle systems are examined in terms of design and operating characteristics and potential applications. A brief history of the development of Saturn V is followed by a discussion of potential cost-saving simplifications. Potentially attractive intermediate payload derivatives of Saturn V and the use of a nuclear third stage are considered along with potential missions. New concepts and technology discussed include low-cost expendable, partially reusable, and fully reusable systems in which the launch vehicle and spacecraft are integral. The need for, and desired characteristics of, a reusable “space shuttle” system are indicated and a brief description of alternate approaches to obtaining this system are presented.
1969-02-01
Technical Paper
690704
Joseph G. Thibodaux
The Apollo spacecraft has 50 rocket engines arranged in 7 separate and independent systems. During a single mission there are approximately 100,000 rocket engine firings. In order to accomplish a lunar landing, all engines and systems must work reliably. Redundant components and system back-up capabilities are provided in the design. Back-up operational modes are possible to return the crew safely at all times in the event a system failure causes a mission abort. These crew safety requirements impose many unusual constraints that are not required in launch vehicle or unmanned propulsion system designs. These requirements and their effects on design and operation are discussed and the systems operational experience on Apollo models are presented.
1969-02-01
Technical Paper
690707
Richard J. Arnold
Designing a high degree of survivability in a light combat aircraft presents a challenge to engineers because of the conflicting demands for simplicity, low weight and cost, and maximum protection. The North American Rockwell OV-10A Bronco is an example of a current program to provide original design survivability through reduction of the vulnerability of fuel, powerplant, flight control, and crew systems. This reduced vulnerability, combined with the ability to evade enemy ground fire, results in a high probability of survival in battlefield close support operations.
1969-02-01
Technical Paper
690709
Howard S. Davis
This paper discusses the need for and results and goals of the Air Force safety program. The basic aim of this new safety program is to analyze each component and procedure of a system or modification of an existing system and then evaluate any imminent hazards. As a result, action will be taken to prevent the manufacture of any hazardous equipment. This approach will reduce any materiel deficiencies, including improper selection of materials or improper design of equipment.
1969-02-01
Technical Paper
690710
R. Emerson Harris
The NASA System Safety Program, its implementation and supporting organizational structure are discussed. The program is related to overall safety activity and evolution of concepts, which were based on previously identified constraints. The concept of “establishing the requirements and then measuring the system safety program performance against those requirements” was described as the implementing technique. The results of the program are reviewed.
1969-02-01
Technical Paper
690711
Jack N. Funk, Richard B. Clarke
Specific differences in requirements and philosophies of the design safety discipline which distinguish commercial from military aircraft programs are described. The military demands for quantum jumps in technology for its aircraft products are compared to the long-standing commercial requirements imposed by Federal Aviation Regulations and the constraints of a competitive marketplace. The check and balance concept is defined for implementing a product safety program within the Boeing Commercial Airplane Group.
1969-02-01
Technical Paper
690670
A. B. Billet
The 747 airplane, the largest commercial airliner, is the first U. S. airplane for airline service to use fully powered flight controls without manual reversion. The four hydraulic systems permit the highest degree of reliability per system operation with all major controls powered by dual-tandem actuators or having redundancy in location of operation. This airplane has 500 hydraulic hp as compared to the 87 hydraulic hp used on the 707 airplane. Each system is powered by an engine-driven pump and an air-driven pump. The latter is operated during peak demands only. In 17,000 hr of ground and flight tests, the 747 hydraulic systems have achieved and exceeded required performance and reliability.
1969-02-01
Technical Paper
690668
Stanley Greenberg
Problems and limitations associated with JP fuels at high Mach numbers have led to an interest in fuels with better heat sink and high temperature capabilities such as methane studies have shown methane to offer performance advantages for SSTs relative to JP, but the overall attractiveness of methane will depend upon the extent advantages are nullified by practical disadvantages. Problems and penalties of storing methane in an aircraft constitute some of the importrant “practical disadvantages.” Several representative methane storage schemes for Mach 3-6 transport aircraft are evaluated, primarily on the basis of minimum weight. Fuel system weight (including tankage, insulation, plumbing, boiloff, etc.) is shown to be 6.3-13.6% of the fuel weight for methane depending upon the type of storage scheme used and upon the aircraft speed and range. By contrast, fuel system weight for JP is 2.5-3% of the fuel weight.
1969-02-01
Technical Paper
690667
R. A. Vere
A laboratory test rig has evaluated European jet fuels with regards to lubricity and shows that the more highly refined fuels are poorer in lubricity than the conventionally refined fuels. The addition of a surface active additive such as a corrosion inhibitor improves lubricity. Experience of additive addition to fuel for aircraft of two European airlines in 1968 confirms laboratory results. Highly polar compounds extracted from conventionally treated fuels significantly improve lubricity when added to highly refined fuels. The blending of 10-20% of a conventionally treated fuel to a highly refined fuel improves lubricity to the level of the conventional fuel.
1969-02-01
Technical Paper
690666
David A. Turner, William E. Springer
This paper describes the structural design of a composite material front housing for the T56 turboprop reduction gear case. The objective of the composite gear case is demonstration of the feasibility of composites for stiff, lightweight gear reduction cases and the advancement of structural and material technology. Turboprop reduction gear assemblies have typically used magnesium or aluminum for the case structure. Magnesium has reasonable strength properties and low density but the modulus is also low; furthermore, it exhibits poor corrosion resistance. Aluminum has sufficient strength but the specific stiffness, E/ρ, is similar to magnesium so the case is heavy for many applications. In addition to these disadvantages, the mounting requirements for propellers, engine, and transmissions dictate high loads on the gear case structure.

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