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currently underway to resolve Project ACE findings are discussed.

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A74-18680* # Project management Factors leading to success or failure. A. J. Kelley and D. C. Murphy (Boston College, Chestnut Hill, Mass.). American Institute of Aeronautics and Astronautics, Annual Meeting and Technical Display, 10th, Washington, D.C., Jan. 28-30, 1974, Paper 74-282. 6 p. Members, $1.50; nonmembers, $2.00. Grant No. NGR-22-003-028.

This paper presents initial findings of a study designed to detail the relationships among situational, structural, and process variables as they relate to project effectiveness. In the paper, emphasis is placed on delineating those variables which tend to improve and those which tend to impede project effectiveness. (Author)

A74-18890 * # A program for transition research. E. Reshotko (Case-Western-Reserve University, Cleveland, Ohio). American Institute of Aeronautics and Astronautics, Aerospace Sciences Meeting, 12th, Washington, D.C., Jan. 30-Feb. 1, 1974, Paper 74-130. 8 p. 27 refs. Members, $1.50; nonmembers, $2.00.

Review of the nature and goals of the NASA Transition Study program aimed at developing procedures yielding information relevant to anomalies in boundary layer transition data and future estimation of transition Reynolds numbers. Specific experimental programs have been formulated that emphasize careful and redundant measurements, documentation of the disturbance environment, and elimination of facility induced transition, whenever possible.

M.V.E.

A74-18998
T700 aims at low combat maintenance. M. L.
Yaffee. Aviation Week and Space Technology, vol. 100, Jan. 28,
1974, p. 45, 47-49.

The described T700-Ge-700 engine under development is a small compact turboshaft engine. The 15-sph engine has been selected by the Army to power its utility tactical transport aircraft and advanced attack helicopter. A distinctive feature of the engine is an integral inlet particle separator which will operate all the time with the engine on and which is expected to reduce significantly engine maintenance on helicopters operating in severe combat environV.P. ments.

A74-19568

An evaluation of some methods for determining the R&D budget. B. Naslund (Stockholm School of Economics, Stockholm, Sweden) and B. Sellstedt (Stockholm, Universitet, Stockholm, Sweden). IEEE Transactions on Engineering Management, vol. EM-21, Feb. 1974, p. 24-29. 30 refs.

Models proposed by the author et al. (1972), Dean et al. (1962), and Gaver et al. (1972) for making decisions on R&D investment are evaluated and are compared with industrial practices. Significant differences between the requirements of these models and the policies of firms are noted. Suggestions are made for bringing business practices in shaping R&D budgets closer to the results of theoretical studies. V.Z.

A74-19569 *

Determining an optimal set of research experiments. B. H. Adams (NASA, Langley Research Center, Business Data Systems Div., Hampton, Va.) and C. E. Gearing (Dartmouth College, Hanover, N.H.). IEEE Transactions on Engineering Management, vol. EM-21, Feb. 1974, p. 29-39. 17 refs.

Description of a procedure for optimal selection of research experiments to be performed aboard the Space Shuttle. The procedure is designed to provide the study team with a credible approach to their task. The procedure is characterized as methodologically sound and based on assumptions which reasonably approximate the real conditions. The data-gathering techniques proposed are accepted by scientifically trained personnel. V.Z.

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A74-19630 # Protection of the hearing organ Current status, requirements, and possibilities (Ochrona narzadu sluchu-stan aktualny, potrzeby mozliwosci). H. Czarnecki and W. Wasala (Wojskowa Akademia Medyczna, Warsaw, Poland). In: Conference on the Topic of Combatting Noise, 3rd, Warsaw, Poland, November 5-8, 1973, Proceedings. Warsaw, Polska Aka

demia Nauk, 1973, p. 69-73. In Polish.

Measures currently used to safeguard the hearing of personnel exposed to noisy industrial environments are described and critically evaluated in terms of intrinsic drawbacks and enforcement problems. Topics considered include compliance with hearing safety standards, medical selection and periodic examination of personnel exposed to noise, use of personal protective gear such as ear plugs, coordination among medical authorities and industrial management, and standardized definition of hearing damage levels. T.M.

A74-19353 # Hydrogen Make-sense fuel for an American supersonic transport. W. J. D. Escher (Escher Technology Associates, St. Johns, Mich.) and G. D. Brewer (Lockheed-California Co., Burbank, Calif.). American Institute of Aeronautics and Astronautics, Aerospace Sciences Meeting, 12th, Washington, D.C., Jan. 30 Feb. 1, 1974, Paper 74-163. 11 p. 21 refs. Members, $1.50; nonmembers, $2.00.

Arguments in favor of the use of liquid-hydrogen fuel for power supersonic transport aircraft are presented, with a view toward the 'better and faster' SST the U.S. will eventually build. It is seen that, in addition to the economic and operational advantages, the use of hydrogen will establish a sound basis for evolving out of the present self-limited petroleum era into tomorrow's hydrogen economy. V.P.

A74-19494 B-1 operational test and evaluation - An early look. E. Sturmthal (USAF, Flight Test Center, Edwards AFB, Calif.). (Society of Experimental Test Pilots, Symposium, 17th, Beverly Hills, Calif., Sept 26-29, 1973.) Society of Experimental Test Pilots, Technical Review, vol. 11, no. 4, 1974, p. 57-61.

Details of the B-1 flight test schedule are examined. Phase I represents the testing on three aircraft that occurs before and supports a production decision, now scheduled for May 1976. Phase II is the remaining flight testing presently on contract to be performed after the production decision on the three aircraft. Any additional work that would extend flight testing on the first three aircraft beyond September 1978 would be conducted in Phase III.

G.R.

A74-19698
The billion-mark failures (Die Milliarden-
Pleiten). R. Olsen. Flug Revue/Flugwelt International, Feb. 1974, p.
25-28, 33-36. In German.

The expenditure of about 1.5 billion German marks for the development of VTOL aircraft in West Germany has been criticized because the objective to obtain weapons systems for series production could not be obtained. The reasons for this failure are investigated as a basis for an approach to avoid similar mistakes in the future. The present status of the aircraft production in the various states is explored together with questions of the military and political situation in Europe which the government of West Germany has to take into account. Attention is given to details of the conditions under which the rearmament of West Germany took place after the Second World War. The errors committed in the planning of defense developments are pointed out together with a number of unrealistic aspects in the foreign policy of West Germany. Details of a feasible contribution of West Germany to the defense of Western Europe are briefly discussed. G.R.

A74-20468 The conversion of the gold value in an application of the international aviation agreements (Die Umwandlung des Goldwertes bei Anwendung der internationalen Luftfahrtabkommen). H. A. Perucchi. Zeitschrift für Luftrecht und Weltraumrechtsfragen, vol. 23, Jan. 1, 1974, p. 40-45. 12 refs. In German. (Translation).

Liability regulations in the Warsaw Convention are based on a French franc which is equivalent to 65 1/2 miligrams of gold with a

fineness of 900. The corresponding value can be converted in the equivalent amount of money of the national currency of each country. Problems connected with fluctuations of the gold value are considered together with discussions concerning the gold price at a convention in Montreal in April 1973. Effects of the evaluation of gold on insurance regulations are also examined. G.R.

craft design goals, route performance, investment cost, operating costs, growth prospects, passenger appeal, technical specifications, and maintenance requirements. The second area includes operating goals, service quality, revenue production, aircraft life, utilization, and reliability. The fundamentals of good aircraft design are outlined, and the importance that manufacturer and operator adhere to these fundamentals is emphasized. V P.

A74-20534 *
The Space Shuttle Program and its technology.
R. F. Thompson (NASA, Washington, D.C.). In: International
congress of space benefits; Proceedings of the Nineteenth Annual
Meeting, Dallas, Tex., June 19, 20, 1973.

Tarzana, Calif., American Astronautical Society, 1974, p. 45-68. 22 refs.

Review of the considerations leading to the development of the Space Shuttle system, followed by a description of the system and an analysis of the current program development status. The Space Shuttle system arose out of a need for a reusable vehicle that could routinely carry large payloads (up to 65,000 lb) into earth orbit and return on a cost-effective basis. The system, as currently baselined, consists of a manned reusable Orbiter vehicle and the booster hardware for ground launching. The proposed Orbiter will be 123 feet long, double delta-winged, and roughly the size of a DC-9. The Orbiter will normally carry a crew of four who will work without space suits in a shirtsleeve environment. The Orbiter will be boosted into space through the simultaneous operation of two solid propellant booster rockets and the Orbiter's three high-pressure liquid oxygen/liquid hydrogen main engines. The Orbiter will have reusable external insulation, since each vehicle will have a design life of ten years. A.B.K.

A74-20927

Allocating time to repair distributions. D. J. Davis and C. B. Morrison (McDonnell Douglas Astronautics Co., Huntington Beach, Calif.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 12-16. 5 refs.

Current contracting practices for complex systems require that repair time limitations be defined for use as controls for system availability and cost of ownership. These limitations frequently include a required mean and maximum repair time. It is good management practice to define the allowable maintenance task time limitations for the various subsystems and to do so in a way that will, when achieved, satisfy the requirements which have been defined at the system level. Allocation, in this context, provides standards for the design of the various subsystems. The statistical significance of the relations between the mean and the variance, for allocation purposes, was explored and expanded to the technique developed here. This approach has been to provide a technique for allocating mean and maximum repair times to the sub-indentures and to do so in an explicit fashion that will meet the overall system requirements. (Author)

A74-20835 # Space applications What the people want. J. W. Symington (U.S. House of Representatives, Washington, D.C.). American Institute of Aeronautics and Astronautics, Annual Meeting and Technical Display, 10th, Washington, D.C., Jan. 28-30, 1974, Paper 74-248. 10 p. Members, $1.50; nonmembers, $2.00.

The benefits which have accrued to our citizens from the advent of technological (in particular, meteorological and communications) satellites are noted, and the contributions of the Space Applications Program are reviewed. The necessity of continuing governmentsupported R & D effort in the field of technological satellites, and especially of advancing and accelerating the ERTS program, is emphasized. V.P.

A74-20836 # Aircraft life cycle profitability The manufacturer's challenge. R. E. Brown and J. J. Italiane (Boeing Commercial Airplane Co., Seattle, Wash.). American Institute of Aeronautics and Astronautics, Annual Meeting and Technical Display, 10th, Washington, D.C., Jan. 28-30, 1974, Paper 74-280. 15 p. Members, $1.50; nonmembers, $2.00.

The ways in which the aircraft manufacturer influences the profitability of the airplane during the life cycle is shown, starting with the design and construction phases, and terminating with the aircraft's useful life. It is shown that the manufacturer influences all the investment cost, somewhat less than half the airplane operating cost, a small part of traffic costs, and most of the useful life parameter. He also has a substantial influence on the earning capability.

A74-20837 #

V.P.

Aircraft life cycle profitability The operator's challenge. J. G. Borger and L. H. Allen (Pan American World Airways, Inc., New York, N.Y.). American Institute of Aeronautics and Astronautics, Annual Meeting and Technical Display, 10th, Washington, DC., Jan. 28-30, 1974, Paper 74-281. 9 p. Members, $1.50; nonmembers, $2.00.

Two fundamental areas in which the operator can influence aircraft life cycle profitability are examined. The first area includes

A74-20928
A comparison of demonstrated and achieved
equipment maintainability. F. S. Balogh, J. F. Hennessey, and D. E.
Reynolds (Philco Ford Western Development Laboratories, Palo
Alto, Calif.). In: Annual Reliability and Maintainability Symposium,
Los Angeles, Calif., January 29-31, 1974, Proceedings.
New York, Institute of Electrical and Electronics
Engineers, Inc., 1974, p. 17-20.

This paper discusses maintainability demonstrations conducted by the Western Development Laboratories Division of the PhilcoFord Corporation on company and associate contractor developed equipments over the past 5 years. The maintenance history of some groups of demonstrated equipments installed in their operational environment was analyzed, and the demonstrated Mean Time-ToRepair (MTTR) was compared to the achieved MTTR's. Reasons for the differences found between the demonstrated and the achieved MTTR's are presented and corrective measures are suggested.

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(Author)

A 74-20931 Life cycle system/cost effectiveness. E Peter (USAF, Washington, D.C.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 48-51.

System effectiveness and cost effectiveness models are basic to most forms of system analysis and trade studies. There is one important feature of these models, however, that is not well used. This feature is the life cycle aspect, or a model's capability to be used and to provide useful information in support of the analyses and trade studies, throughout the life of the system that it is modeling. It is a principal objective of this paper to show the use of such models, on a phase-by-phase basis, and to demonstrate the life cycle characteristics of these models. (Author)

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Calif.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings.

New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 52-55. USAF-sponsored research.

A relatively new Department of Defense procurement policy implementing a design-to-price concept is an extremely strong incentive to industry to force successful integration of reliability and maintainability (R&M) into the design process. The AN/ARN.XXX TACAN development program is a design-to-price procurement which specifies: (1) a fixed maximun unit price in production quantities, (2) guaranteed mean time between failure, (3) failure-free warranty, and (4) life cycle cost incentive. Industry's ability to adequately respond to these forcing functions depends upon its capability to integrate reliability and maintainability, as well as all of the other integrated logistics support disciplines, into the design process. The Government ensures technical competition by selecting two or more contractors to perform a parallel design and development for a competitive fly off before selecting the production contractor. This places heavy emphasis on the successful integration of reliability and maintainability into the design process. (Author)

establishes the interactive program elements including how much, how soon, and how to actually realize the equipment reliability desired. The model encompasses the following program stages: proposal, conceptual, design and development, preproduction, production, and field deployment. (Author)

A74-20937
Reliability testing pitfalls. E. F. Thomas
(General Dynamics Corp., Convair Aerospace Div., Fort Worth,
Tex.). In: Annual Reliability and Maintainability Symposium, Los
Angeles, Calif., January 29.31, 1974, Proceedings.

New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 78-83.

Important factors which have to be taken into account in connection with basic program management in order to insure the conduction of adequate reliability tests are discussed, giving attention to factors which delay the start of the tests, tight delivery schedules, unsuccessful tests, and problems in predicting equipment complexity. Other critical factors which have to be considered are related to the conduction of the tests and the classification of equipment failures. G.R.

A74-20933

Integration of R&M into the design process. R. T. Walker (RCA, Camden, N.J.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 56-59. A new organizational approach in which the design engineer is given a more direct responsibility for the reliability of his design is discussed. This approach has been used in the case of the development of manpack radios for the U.S. Army. The reliability program outline presented takes into account aspects of management and control, vendor reliability, a program review, reliability analysis, parts reliability, a program review, and design reviews. G.R.

A74-20935

Computer software synergism integrates R/M design. K. G. Blemel. In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 68-72.

Problems concerning the integration of reliability and maintainability practice into the design phase of equipment manufacturing are discussed, giving attention to a method for integrating reliability, maintainability and other design parameters in a unified data base. An example presented of a skeletal entry in a form which is acceptable for computer assimilation. Changes to the data base files are discussed together with the basic rules for structure and syntax used in the files and the various types of entries. The systems effects analysis produces output which provides information regarding system failure and degradation, taking into account several viewpoints. G.R.

A74-20939

The simulation of production test economics. R. G. Cottrell (Hughes Aircraft Co., Tucson, Ariz.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif. January 29-31, 1974, Proceedings New York, Institute of Electrical and Electronics Engineers, Inc, 1974, p. 91-99. 5 refs.

The simulation approach to the assessment of production test economics is discussed Basic functional models which describe the defect and cost flow through a production line are derived in detail The effects on product cost and reliability of alternative test policies is accomplished by exercising the simulation composed of the functional models. Minimum cost testing is accomplished by assign. ing a reliability constraint on the product or by defining a reliability-cost penalty function Two examples are presented which illustrate the application of production test economics simulations for missile electronics units (Author)

A74-20940

An engineer looks at product liability cases. F S. Badger. In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif, January 29:31, 1974, Proceedings New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 100-'03.

The court procedures used in a product liability case examined, giving attention to the role of the technical expert. The first step of the investigator should be a determination of the causes of failure. Questions of standards are discussed together with aspects of failure analysis, laboratory testing, appearance in court, jury awards, and the protection against product liability actions. It is pointed out that corrosion and joining problems are in many cases responsible for the early failure of a product G.R.

A74-20936
Reliability program elements Who needs
them. J. E. Bridgers, Jr. (Hoffman Electronics Corp., El Monte,
Calif.). In: Annual Reliability and Maintainability Symposium, Los
Angeles, Calif., January 29-31, 1974, Proceedings.

New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 73-77.

Within all equipment catagories there exists an ever increasing requirement for proper selection and phasing of the multitude of reliability activities. Each one of these may be performed in varied levels of thoroughness for any particular program. This, obviously, presents a confusion of multiple interrelated decisions which must be made and explained to others for their review. A logical technique for quantitizing the effectiveness of performing these elements is presented. Examples are provided showing the application of this technique to typical problems. A program evaluation technique

A74-20942

The choice between attribute and variables data. L. D. Maxim (Mathematica, Inc., Mathtech Div., Princeton, N.J.) and R. Roeloffs (New York, Polytechnic Institute, Brooklyn, N.Y.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings.

New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 130-135.

Decision rules for the selection of an optimal test technique are developed, taking into account the case in which both attribute and variables data can be obtained. The decision rules presume knowledge of the relative cost of testing. It is also assumed that information is available concerning the precision of the measurement of variables data and the probability of misclassification of attribute test results. The decision problem is illustrated with the aid of an example involving the design and the testing of safing and arming devices for ordnance components. G.R.

A74-20944

Some experiences from the use of an LCC approach. H. Ebenfelt (Systecon AB, Stockholm, Sweden) and S. Ogren (Swedish Air Materiel Administration, Stockholm, Sweden). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 142-146.

The LCC approach discussed in this paper has been developed to suit a specific need, determined by factors such as the competitive situation, the time horizon and associated risks, program and contract characteristics. These factors and their implications on techniques and procedures used during different phases of system acquisition are reviewed. A brief description of the approach is included as it applies to conceptual studies, source selection and contracting. The experience thus gained is finally summed up in statements pointing at present problem areas but also indicating advantages.

(Author)

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A74-20949
System safety and human factors Some
necessary relationships. E. S. Brown (Texas Instruments, Inc., Dallas,
Tex.). In: Annual Reliability and Maintainability Symposium, Los
Angeles, Calif., January 29-31, 1974, Proceedings.

New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 197-200. 6 refs.

The analysis of man-machine interactions is an important factor in any human factors or safety program. The general objective of the analysis effort is usually to identify and describe selected interactions prior to taking corrective, preventive, creative, or other supporting actions. An element of increasing importance to the human factors domain is human error, including reliability of task performance. Questions of safety labeling are also discussed together with approaches for supporting the equipment design process to improve personnel and equipment safety. G.R.

A74-20952

Simulation of dispatch reliability for a fleet of large commercial aircraft. M. O. Locks (Oklahoma State University, Stillwater, Okla.) and G. L. Pauler (Los Angeles, Loyola University, Los Angeles, Calif.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 226-228.

For a fleet of large commercial aircraft, management's objectives include attaining a prespecified dispatch reliability (DR), a measure of the radio of departures within a stated time of scheduled departure to total departures. Data from the first 18 months of revenue operation are used to assess and predict DR for future periods. Goodness-of-fit analysis shows the delay times for departures delayed six minutes or more tend to fit lognormal distributions. The estimated distributions were used to assess DR both for historical data and future periods by simulation. The results show that the delay time is too large to meet management's objectives. (Author)

A74-20954

Equipment procured reliability and real-life survival. O. Markowitz (U.S. Navy, Aviation Supply Office, Philadelphia, Pa.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings.

New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 249-255. 6 refs.

Recommendations are made for improving communications between suppliers and users of equipment in the area of reliability. It is concluded that the hazards in real life equipment flow and end use do not compare to those inherent in equipment laboratory verification of failure rate. Thus any translation of laboratory or specified failure rate as a direct expectation of end use failure rate is inadequate. There is much needed in the way of the operator's understanding of what is required from contractors in the context of

A74-20956
Technology transfer through GIDEP. E. T.
Richards (U.S. Navy, GIDEP Administration Office, Seal Beach
Corona, Calif.). In: Annual Reliability and Maintainability Sym-
posium, Los Angeles, Calif., January 29-31, 1974, Proceedings.
New York, Institute of Electrical and Electronics

Engineers, Inc., 1974, p. 266 273.

Description of a cooperative effort in technology transfer between government and industry to reduce costs and enhance systems reliability through the media of the Government-Industry Data Exchange Program (GIDEP). Techniques of technology transfer through the use of a centralized reliability data bank are reviewed, and important program functions such as the ALERT system, Urgent Data Request (UDR) system, and Metrology Data Interchange are explained. The current expansion of GIDEP into Failure Rate Data Interchange; Defective Parts and Components Control; Secretariat for Electronic Test Equipment, and International Reliability Data Exchange are discussed. Examples of the outstanding cooperation achieved between government agencies and industry participants, and the benefits they gain through active program utilization are also described. (Author)

A74-20963

Human reliability in man-machine interactions. R. L. Huston and A. M. Strauss (Cincinnati, University, Cincinnati, Ohio). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 329-334. 11 refs.

New concepts are presented that provide a framework for coordinating the methods and ideas in use among system reliability engineers with the techniques and theories of behavioral scientists. Sociomechanical analysis, simple examples of which are described, is shown to be readily applicable to man-man interaction (sociological system) problems, and multilateral interactions, such as manmachine-management-government-public interactions. The achievement of optimum man-machine interaction may be aided by the proposed methods. Pertinent analytical results include the findings that: (1) man's productivity does not become optimal until some time after machine maintenance; (2) his productivity is optimal midways between maintenance operations; and (3) following a machine breakdown, man's productivity does not attain the prebreakdown level even after repairs have been made. M.V.E.

A74-20966
The use of warranties for defense avionics
procurement. H. Balaban and B. Retterer (ARINC Research Corp.,
Annapolis, Md.). In: Annual Reliability and Maintainability Sympo-
sium, Los Angeles, Calif., January 29-31, 1974, Proceedings.
New York, Institute of Electrical and Electronics
Engineers, Inc., 1974, p. 363-368. 11 refs. Contract No.
F30602-73-C-0207.

Constraints on military budgets in the face of mounting operation and maintenance costs have prompted a search for additional methods of cost reduction. This paper describes an investigation into the use of warranties as a means of making the vendor more responsible for field performance, thus motivating him to produce reliable equipment and introduce improvements as necessary. A life-cycle-cost model is described and used to examine the relative economic advantages of warranty versus nonwarranty purchases. The major conclusions reached are that a properly constituted and applied warranty can yield significant reliability and life-cycle-cost benefits and that broader use of erranties in military avionics procurement is advisable. (Author)

A74-20968

Reliability growth - Actual versus predicted. C. N. Stoll and W. S. Oliveri (Raytheon Co., Electromagnetic Systems Div., Goleta, Calif.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 391-395.

Evaluation of a number of case histories of sudden unexpected decreases in device reliability, observed contrary to normal predictions in such standard, mature products as power wirewound resistors, high-voltage triodes, pulse transformers, and bandpass filters. The failure causes involved are discussed, along with the necessary corrective action. M.V.E.

A74-20969

DC-10 avionics parts reliability in review. R. S. Babin (Douglas Aircraft Co., Long Beach, Calif.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York,

Institute of Electrical and Electronics Engineers, Inc., 1974, p. 403-408.

The McDonnell Douglas DC-10 aircraft program has demonstrated the effectiveness of a number of reliability and quality engineering controls and disciplines. Notable among them are several key controls on electrical, electronic, and electromagnetic parts in the avionics systems. A qualitative review of those parts controls is presented, utilizing DC-10 case histories (actual part-failure problems) as a basis for discussion and evaluation of the relative effectiveness of the controls. The controls that have shown most room for improvement, judged by the impact of their deficiencies on fielded equipment reliability, are: (1) part-failure reporting, analysis, and corrective action, (2) multiple-source part procurement, and (3) the designation and control of microcircuit part quality.

A74-20970

(Author)

Time series modeling. P. B. Robinson (AT & T, New York, N.Y.) and A. P. Stamboulis (New York, Polytechnic Institute, Brooklyn, N.Y.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, p. 413-419. 12 refs.

A sequence of component failures or a stream of investment returns may quite conceivably possess significant serial correlation. Preference orderings among alternative investments or system configurations, then, will be heavily dependent on the time series structure of the observable process as well as the levels of its autoregressive parameters. Here, we concentrate on the latter problem. A new detection statistic for the autoregressive parameter of a first order autoregressive process is developed. Its power is shown to be comparable to that of the Durbin-Watson Statistics for the model considered. Moreover, it is related to a two-sample moving range statistic. As such, it is easy to chart and easily understood by practioners of quality control. (Author)

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Management teams are required to make several key decisions during the conceptual phase of a project. Analytical prediction techniques aid the decision maker by providing timely insight into the availability and consequences of alternates. This paper describes the application of a computer code entitled PROSIM (PROject SIMulation) as a project planning prediction technique. PROSIM uses a Monte Carlo simulation to evaluate the impact of alternate system design concepts and associated procurement and operating strategies on system operation and cost. This technique has been used successfully and has demonstrated its capability to meet stringent requirements for realism. The specific types of problems amenable to evaluation with PROSIM are presented, and the capabilities and mechanization of the code are discussed. A sample problem is described to show how PROSIM is used to translate the statement of the decision variables into output displays that facilitate decision making. T.M.

A74-20987

Risk analysis A program management tool. J. D. Gault (Boeing Co., Wichita, Kan.). In: Annual Reliability and Maintainability Symposium, Los Angeles, Calif., January 29-31, 1974, Proceedings. New York, Institute of Electrical and Electronics Engineers, Inc., 1974, р. 548-551.

Investigation of the adaptability of risk analysis methodology to evolutionary situations such as environmental problems. Techniques presently used to evaluate airplane fatigue risks are shown to be applicable to any situation having an inherent risk which increases with time but may be countered by periodic application of corrective measures. Control of our environment, mass transportation, and consumer protection are among the problems that fall into this category. The investigation results indicate that risk analysis provides an approximate answer to the right problem by tying together the interrelated influences in a complex system. M.V.E.

A74-21013

Microbiological standards for frozen foods. M.

D. Appleman (Southern California, University, Los Angeles, Calif.), M. D. Appleman, Jr. (Southern California Permanente Medical Group, Bellflower, Calif.), and M. D. Appleman. In: Cryogens and gases: Testing methods and standards development; Proceedings of the Symposium, Los Angeles, Calif., June 25-30, 1972. Philadelphia, Pa., American Society for Testing and Materials, 1973, p. 3-11. 16 refs.

Factors predetermining quality and safety of frozen food products are discussed along with different types of standards. Attention is drawn to the fact that microbiological standards for frozen foods must be studied thoroughly prior to establishment. The sources and methods of transmission of diseases through the agency of frozen foods and methods of evaluating and minimizing risk are clarified. The inherent inconvenience and danger of establishing microbiological standards for foods without careful evaluative techniques are explained. The impact of microbiological standards for foods upon incipient or frank spoilage is discussed. T.M.

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