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A parametric analysis of the life support systems was completed, from which scaling laws were developed and adapted to computer solutions. This new tool permits the evaluation of a great variety of life support system types and combinations. The interdependencies and interrelations within the life support system itself can be evaluated, as well as the interactions between the life support system, spacecraft, and other systems. Representative data are presented for several partially closed life support system configurations usable for manned Earth orbital missions. The life support systems are principally affected by alternative degree of closure, the functional methods selected for the various subsystems, and mission requirements.

The design of vibration tests involves satisfying both objective and subjective goals with uncertainty about the true reliability of the design. A procedure is outlined whereby the constraints, goals, future states of nature, and candidate test designs are identified. A general statistical decision theory model is used to evaluate the designs based on maximizing expected utility. The paper emphasizes utility theory and utility function formulation. An example spacecraft test problem is presented.

Structural design is discussed as related to the optimization of components and systems. The tools of mathematical programming (including nonlinear, linear, and dynamic programming) employed in the optimization process are treated. Illustrative examples are included.

A vibration isolation system is investigated theoretically and experimentally which combines an active element with a passive system. The resulting system, here called a hybrid vibration isolation system, seeks to give stiff response at low frequencies and soft response at high frequencies without a large resonant response at intermediate frequencies. It is shown that fairly good response can be achieved with reasonable choice of operating parameters.

Some of the fundamental limitations of roll control and vibration isolation are analyzed and discussed. Optimum roll responses to a step input in lateral acceleration are derived from the calculus of variations. The responses show that a pendulous suspension (where the roll center is above the passengers) can be made to exert zero net lateral acceleration on passengers; whereas, a finite lateral acceleration will always be present during maneuvers of vehicles equipped with conventional suspensions (where the roll center is below the passengers). The lower limitation on roadway-induced vibration is presented as a trade-off between vibration and the clearance space between the sprung and unsprung masses or between the sprung mass and the roadway. Finally, the substantial benefits accruing from the use of preview control (where the roadway ahead of a moving vehicle is sensed) are presented.

This paper discusses operational experience with the integrated Saturn V launch vehicle, to be used as the booster for the Apollo manned lunar landing mission. Emphasis is placed on NASA's management approach to the solution of technical problems rather than on the problems themselves. Launches to date are summarized, with emphasis on the Saturn V. A discussion flight anomalies and corrective management action is included. The paper concludes with an appraisal of the program to date and makes recommendations for future guidance.

This paper presents a light, but reverent, discussion of some of the Douglas operational experiences on the Saturn V/S-IVB stage. Certain relevant aspects of earlier work on the Thor intermediate range ballistic missile, the Saturn I S-IV stage, and the Uprated Saturn I S-IVB stage are also discussed.

The purpose of this paper is to relate some of the operational experience on the second stage (S-II) of the Saturn V launch vehicle. A review of the performance of the major stage systems during static firing and flight operations is presented. The malfunction experienced was the premature shutdown of two J-2 engines. The S-II stage has accomplished all of its mission objectives except that the propulsion demonstration was only partially accomplished because of the engine shutdown.

A concerted, systematic program for design and development of a high reliability booster has been developed by The Boeing Co. for use in the NASA Apollo Manned Space Flight Program. The S-IC program stressed discipline in analysis, testing, and management to insure a consistent and reliable end product. Evaluation of the operational experience from this program resulted in a complete systems analysis program being established which encompassed single-point failure mode and effect analysis, double-point failure mode and effect analysis, and analysis of potential human-initiated failures. These activities serve to predict stage reliability, identify reliability critical components, and provide a constant feedback to design and management to permit timely hardware redesign, retesting or revision to operating procedures to eliminate or minimize the probability of failure.

Abandonment of the concept that gas engines can be operated economically using straight mineral oils and clay filters and the switch to detergent oils designed for specific use in natural gas engines has been handicapped by attempts to use conventional automotive or diesel metallo-organic detergent oils, and by the attempts to develop ashless oils without investigating all of the parameters and pitfalls associated with the use of ashless dispersants. At present, the weaknesses of ashless oils can be overcome only through the use of a balanced combination of the proper base stock and certain metallo-organic detergents. Careful analysis of engine operations over relatively long periods of time will demonstrate to the operator that ash from a properly designed natural gas engine oil does not adversely affect engine operations. It has been our experience that laboratory engine tests are of relatively little use in the evaluation of natural gas engine oils.

Tests employed for the evaluation of used lubricating oils generally involve the determination of changes in viscosity, insolubles buildup, contamination with metals, fuel, water, glycol and other physical and chemical changes. The author attempts to point out the relative significance of these various tests in terms of engine operation. Engine test data is also presented which shows the relationship between the oil condition measured by some of these tests and the engine performance characteristics. The data indicates that increase in alkalinity improves rust protection and reduces engine varnish and PCV valve restriction in certain additive combinations. Engine wear appears to be associated with the accumulation of contaminants in the lubricant measured as pentane insolubles and total acid number.

This paper presents analytical lubricant technology for determining the condition of 2 and 4 cycle automotive and railroad diesel engines through used oil analysis. The paper supplements ASME paper 64-OGP-16, and SAE paper 650139 wherein two new analytical techniques were presented for gas and gasoline engine oil analyses. These two methods, in addition to used oil atomic absorption spectroscopic analysis, are presented herein and shown to predict diesel engine condition with regard to deposit level, maintenance practices, and equipment malfunction, as well as to provide information on lubricant condition and contaminants.

Applying systems analysis to the C-5 the basic analytical tools used were computer programs which evaluated C-5 characteristics and determined cost effectiveness. Three programs used to evaluate characteristic effectiveness were the loading program, productivity program, and effectiveness analysis program. The fourth program, a life cost model presentation, determined airplane cost effectiveness, and is presented in two levels-conceptual and contract definition phase, and acquisition phase. A description of Pert-Tech techniques is also presented outlining how managers on the C-5 program were able to assess the technical health of the program and to pin-point problem areas where action had to be taken during developmental work. Systems analysis applications presented illustrate one of the first cases where detailed alternatives on a major transportation system were measured against total system effectiveness to attain maximum product performance.

Methods presently in use by the Penn Central Railroad for draining diesel locomotive engine crankcases are discussed. We believe these criteria apply to other types of diesel as well as gasoline engines. The author explores the use of oil insoluble values as limiting factors of an oil's effective life. The effectiveness of blotter spot interpretations and their meaning in evaluating the condition of used lubricating oil is pointed out. Although controversial, the author feels it as well as later modifications of the technique can be most meaningful to the engine fleet maintainer.

Design criteria utilized in the development of an air conditioning system for a 50–70 passenger jet aircraft for the short haul market are presented. Because the aircraft’s mission requires high speed over short stage lengths, special problems result. A short haul aircraft is described and related to the environmental system. Concepts for air conditioning that were considered as well as the one recommended are discussed. Final air conditioning design is reviewed relative to performance, operation, safety, reliability, and maintainability. The result is a package with larger than average cooling performance per passenger and design features not found in any other aircraft environmental system.

IDEAS (Integrated Design and Analysis System) is a new approach directed toward the rapid definition of design loading conditions and internal structural element loads needed for the sizing and analysis of the primary structure of an entire aircraft. It is an integrated collection of many different kinds of computer programs and formalized calculations which are performed in particular sequence. Complete integration is of prime significance. Output data from any one kind of computer program is in the precise format required as input for subsequently used programs of the system. System capability is sufficiently broad to provide state-of-the-art analysis procedures for both variable-sweep supersonic aircraft and fixed-wing subsonic aircraft. It treats all applicable flight maneuvers, landing and catapult conditions, taxiing conditions, gust and flutter analyses.

This paper describes an analytical model that may be used to determine the impact of maintainability (operational and resource requirements) on aircraft system design. The major advantage of analytical computer oriented models is the depth and detail of investigation that can be accomplished as a basis for design decisions. The model, designated SOURCE (Simulation of Utilization, Resources, Cost, and Efficiency), is designed to accept empirical data to determine realistically the interrelationships between maintainability and aircraft design characteristics.

This paper records the results of some fuel system testing being carried on in England in an effort to simulate the Concorde fuel system and to study the behavior of fuels. The accuracy of the ASTM-CRC Fuel Coker in specifying fuel quality is examined.

The Thor standard launch vehicle (SLV-2) was designed and first flown more than 10 years ago as a quick response IRBM with completely air transportable launch equipment. After deployment overseas in squadron strength, several years ago it was removed from the strategic weapon system inventory. However, the descendants of the vehicle are still in production as an operational space booster after undergoing continuous improvement through such methods as uprating the main engine and electronics, addition of solid propellant thrust augmentation motors, extension of the propellant tanks, and adding the ability to mate with various upper stage vehicles. Furthermore, the Thor IRBMs returned from overseas have been refurbished and used by the military. Of the two original launch sites, the R&D facilities at Cape Kennedy and some of the Weapon System Training sites at Vandenberg AFB have been converted to space launch duty, making maximum use of the original equipment.

Mars landing vehicle descent propulsion is discussed in the light of the constraints of the mission, the environment, and the interfacing functions. The presence of a largely undefined, tenuous atmosphere is shown to produce a great variability of initial and boundary conditions for the propulsion phase of descent. The mission provides numerous subtle constraints of formidable importance to the propulsion implementation. The current requirement for prelaunch, in-situ, thermal sterilization is paramount among these. A significant, and unresolved, mission-related problem is that of the interaction of landing propulsion on the native environment. For a mission which has as its primary objective the investigation of the Mars environment, landing site alteration is a significant concern. The principal intersystem constraint is that of the flight path guidance logic choice.