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1964-07-01
Magazine
1964-06-01
Standard
ARP450B
This ARP sets forth design and operational recommendations relative to the integrated alerting system to be implemented on the flight deck. It is intended that through the adoption of the design objectives and recommendations incorporated herein, a consistent and effective industry standard will result. Safety of flight is greatly enhanced by an alerting system designed to provide early crew recognition of flight crew operational error as well as aircraft system or component status or malfunction. The alerting system therefore relates to aircraft configuration and flight regime as well as the aircraft systems. To fulfill this objective, the flight deck alerting system must attract the attention of the crew, must state with clarity the nature and location of the problem, must be highly reliable and thoroughly responsive to the operational requirements and environment.
1964-04-01
Standard
J577_196404
This SAE Recommended Practice provides procedures, and information to conduct vibration (impact) tests on lighting devices and their components as well as other safety equipment used on vehicles.
1964-02-01
Standard
AIR805
The purpose of this information report is to present factors which affect the design and development of jet blast windshield rain removal systems for commercial transport aircraft. A satisfactory analytical approach to the design of these systems has not yet been developed. Although detailed performance data are available for some test configurations, rain removal systems will generally be unique to specific aircraft. This, then, requires a preliminary design for the system based on available empirical data to be followed with an extensive laboratory development program.
1964-01-01
Technical Paper
640024
Edward F. Noonan, Angelos Zaloumis
Abstract The problems of vibration and noise aboard ship have been given increased attention by the Navy since World War II as a result of many technological developments and tactical requirements. Many problem areas are identified and those which have particular application in the design of river towboats are reviewed. The paper is addressed primarily to the naval architect, shipbuilder, or operator and identifies those areas in which attention should be drawn during design and development. Specific suggestions and specifications are presented, based on current naval practice.
1964-01-01
Technical Paper
640061
Lloyd R. Maxwell
Abstract Production line quality control techniques are readily adaptable to sound preventive maintenance practices for fleets, by using the same evaluating methods on the same type equipment as used on the production line. Details of malfunction analysis are discussed, as well as a new technique for incorporating reliability projections into fleet data records. Projections made prior to waste is a cost saving maneuver to supplant the method of correcting when waste has been experienced.
1964-01-01
Technical Paper
640057
Jerar Andon, Craig Marks
Abstract Improvement of engine octane requirement by combustion chamber design has been blocked by engine roughness noise. This noise is caused by high rates of pressure rise in the cylinder due to fast-burn combustion. This produces transient noise bursts with an uneven amplitude pattern. The noise amplitude may be reduced by lowering the burn rate or by structure modifications; however, the low rates cause higher octane requirement. With a stiffer engine structure, higher burn rates can be used without roughness noise, but appreciable gains are not practical because of the weight and cost penalties. A new way to eliminate this noise is proposed. If the amplitudes of the noise bursts from each cylinder are made the same, the roughness noise changes to an acceptable sound. This means that the rate of pressure rise in each cylinder must be the same.
1964-01-01
Technical Paper
640379
Robert T. Bohm
Vibration problems with turborotors become more troublesome as machine speeds increase. Designers of today realize that the era of placing rotor critical speeds above the maximum operating speed of the equipment is long past. The dynamic system, being composed of the rotor, bearings, support structure, and even other rotors within the same machine, together with all of the excitations and damping forces significant to the dynamic problem must be understood and manipulated in a manner to make operation reliable. Today’s careful control of these parameters can prevent tomorrow’s problems. Lycoming has developed a method that takes into account all of the significant parameters and predicts the effect of a design change on the rotor system dynamics.
1964-01-01
Technical Paper
640380
Jon. Parkinson
This paper describes a method of attaching masses to a shaft in specified correction planes and eliminating resonant vibration amplitudes. It is shown that the presence of a single form of elastic deflection in the operating range requires only one correction plane and that two forms (that is, two modes of vibration) require two correction planes, and so on. A shaft that will not exhibit resonance in any mode of vibration is one in which every section of the shaft is running about its mass center, and this would require an infinite number of correction planes.
1964-01-01
Technical Paper
640341
Thomas G. Butler
When sensitive parts of a spacecraft experience random excitation, it would be advantageous to determine a causal relationship between the source of excitation and the response. Power spectral density and cross spectral, density are factors in determining this relationship, if the response can be written in terms of the excitation. This paper derives expressions for these density functions in vector modal terms as an attempt to obtain physical interpretation of the random behavior. Experimental verification may be achieved by combining wind-tunnel tests with full scale flight data.
1964-01-01
Technical Paper
640348
D. M. Duel
The equivalence of phase plane representation and matrix transformations is demonstrated. The insight gained from phase plane diagrams is used to generate matrix transformations for use with aperiodic inputs to single degree of freedom systems damped and undamped. The method is extended to multi-degree of freedom systems and single degree of freedom nonlinear cases.
1964-01-01
Technical Paper
640813
C. T. Molloy
Abstract This paper applies four-pole parameter theory to the problem of sound propagation in porous materials. The four-pole equations are derived for a single layer of porous material, as well as for (n) layers in tandem. The exact equivalent electrical circuit for a layer of porous material, as well as lumped parameter approximations, are given. Various applications of the theory are pointed out.
1964-01-01
Technical Paper
640826
John M. Tyler
Abstract This paper presents an analysis of the airport community noise problem, based on the assumptions that some significant adjustments will be made to reduce the impact of aircraft noise on the community, and that these adjustments can be made in an atmosphere of cooperation among engine and airplane manufacturers, airline and airport operators, and communities. Such cooperation can make available combined know-how to arrive at adjustments that will cause minimum loss to all interested parties.
1964-01-01
Technical Paper
640809
T. P. Yin
Abstract The viscoelastic nature of polymers under periodic deformation is discussed from a gneral point of view. The Requirements of elastomeric isolators and dampeners are then developed on the basis of polymer dynamic properties Methods for measuring such properties are presented, with emphasis on the Fitzgerald Apparatus. The dynamic properties of some commercial elastomers as well as of certain experimental candidates are presented and interpreted in terms of potential vibration isolation or vibration damping applications over a wide range of temperature and frequency.
1964-01-01
Technical Paper
640014
M. K. Colby
Abstract Torsional vibration is an inherent phenomenon of a system containing an engine and transmission, separated by a mechanical coupling. Torsionals can, under some circumstances, damage or destroy an engine, transmission, and related parts, and seriously affect driveline life. The vibration cannot be eliminated, but fortunately it can be controlled. This paper describes a typical problem arising from torsional vibration in the aforementioned power train. The methods used to determine the characteristics of the vibration are explained, as is the method of control.
1964-01-01
Technical Paper
640135
Bruce Fader
A variety of forms of lead and leaded materials for controlling noise and vibration is available today. These forms are classified by type and use, and the theory of their performance is examined cursorily in this paper. To describe the application of these materials for acoustic purposes, five examples are given to show their effectiveness in reducing sound levels.
1964-01-01
Technical Paper
640117
J. R. Thomson
The principle cause of objectionable wind noise in the modern automobile is small air leaks in certain critical areas. The aerodynamic shape is insignificant in overall wind noise. The critical areas in order of importance are: 1. Vent window and door to “A” post sealing from the roof rail to about a foot below the beltline. 2. “C” post area at beltline. 3. Upper rear of front door area. 4. All other areas from roof rail to a foot below the beltline. Conclusions reached after extensive testing show that wind noise can be eliminated by good sealing about the doors and windows.
1964-01-01
Technical Paper
640145
D. L. Jones
Automotive body sound control materials chosen for a new model are based on the preceding year's sound package. Modifications are made and tested on actual prototype vehicle installations. The variety of materials used are classified as dampers, barriers, and absorbers, and their properties are evaluated in the laboratory by special types of apparatus. This paper reviews these materials and tests as well as other requirements that are important for performance, durability, and processing.
1964-01-01
Technical Paper
640155
Harry Sternfeld, Robert H. Spencer
Application of fixed wing acoustical criteria to helicopters have not served to ensure optimum environments for the helicopter mission, yet have often imposed unrealistic performance penalties. In this paper the authors suggest means for establishing criteria for internal and external helicopter noise which will assist, rather than retard, the development of this mode of transportation while assuring adequate hearing protection for the passenger.
1963-12-01
Standard
ARP699B
This Recommended Practice is intended to outline the design, installation, testing, and field maintenance criteria for a high temperature metal pneumatic duct system, for use as a guide in the aircraft industry. These recommendations are to be considered as currently applicable and necessarily subject to revision from time to time, as a result of the rapid development of the industry.
1963-11-01
Standard
AIR764
This technical report documents three surveys to determine realistic vibration requirements for skid control systems specifications and obtain updated vibration information for locations in aircraft where skid control system components are mounted.
1963-07-01
Magazine
1963-06-01
Magazine
1963-05-01
Standard
ARP731
The purpose of this SAE Aerospace Recommended Practice (ARP) is to establish recommendations for the design, installation and testing of air vehicle vapor cycle refrigeration systems. These recommendations are representative of the refrigerant cycles.
1963-04-01
Magazine
1963-01-01
Technical Paper
630172
Bruce D. Van Deusen, Alfred D. Bosley
A technique is discussed whereby vehicle vibration problems can be defined and analyzed using a random vibration input, and analyzing the output statistically. The input consists of a random “white noise” input signal to electromechanical shakers which drive the wheel spindles of an actual automobile. The output analysis is of two types. In the one, vibration instrumentation signals are analyzed with an analog computer to yield a direct measurement of the vehicle transfer function. In the second, subjective impressions are analyzed of vibration sensation experienced by passengers within the vehicle. This approach has the advantage of a controlled laboratory experiment in which suspension and structural changes can be analyzed as to their effect on vehicle vibration. It also allows a comparison of subjective impressions with physical measurements.
1963-01-01
Technical Paper
630283
Irwin J. Schumacher, Cecil R. Sparks, Douglas J. Skinner
The problem associated with laboratory evaluation of muffler acoustical characteristics are complicated both by the acoustical considerations involved in obtaining an adequate noise source and by the ambiguities involved in defining what constitutes quality in a muffler built for general application. In order to quantitatively define the characteristics of quality mufflers, an extensive series of field tests were conducted on a variety of sizes and types of mufflers in conjunction with four engine configurations. Work then turned to the development of a wide band siren noise source and acoustical test system which would simulate the high impedance character of an engine exhaust noise source, and in addition generate the necessary intensity and spectral characteristics required to obtain test data over the range of noise conditions encountered in the field.
1963-01-01
Technical Paper
630324
Keith E. Wood
Studies of the causes of torsional vibration in implement and tractor combinations have produced definite rules for design which have eliminated torsional vibration or reduced it to acceptable proportions. There are cases where the natural torsional frequency of the system must be altered to reduce the effect of a forcing frequency. This paper discusses both types and presents means for selecting a suitable powerline stiffness when natural torsional frequency of the system must be altered. When powerline stiffness change is necessary, stiffness is usually decreased. Means of decreasing powerline stiffness, as well as the problems encountered, are considered.

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