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Delivery of high quality fuels to commercial turbine engine aircraft may become more critical for supersonic transport operation. This paper presents high temperature stability test results on current aviation turbine fuel samples taken from refineries and airports throughout the world. Transportation methods involve combinations of tanker, barge, multiproduct pipeline, and truck movements. Data show that, through the application of proper handling techniques, fuels can be transported from refinery to aircraft, through complex distribution systems, with no significant loss in thermal stability. Data also indicate that current aviation turbine fuels are well above the minimum thermal stability specification limits for present subsonic jet aircraft.

To keep pace with man's increased scope of space exploration in the future, it is imperative that fluid power system technology continue to expand its methods and techniques to be able to meet the severe environments indicated on the various planets. Support equipment industries have a prime new field to develop in the maintenance of vehicles in space. Various investigations have discovered basic data that will prove valuable in projecting effective fluid power support for space craft outside the Earth's atmosphere.

The Air Force Space Systems Division's continued development of equipments for the space program is producing problems in engineering for transportability that are even more challenging than those faced in the development of the missile family. The large solid rocket motor (SRM) program's experience in 120-156 in. solid motor transportation and handling will be outlined in this paper. The current state-of-the-art and the anticipated requirements for the future will be discussed as well as emphasizing the impact of transportability resolutions upon program management. The measures implemented in the Air Force Systems Command's 375 Series Manuals to integrate the Engineering for Transportability Program into the design engineering process will be summarized.

The integrate-transfer-launch (ITL) concept of assembly, checkout, transport, and launch of the Titan III vehicle at Cape Kennedy requires a unique facility and special handling and transportation equipment. The launch facility incorporates an entirely new concept for preparing a vehicle for launch. The handling and transportation equipment designed for use in the ITL system includes some that is common to the aerospace industry and some that is entirely new. This paper presents a description of the ITL facility and the ground handling and transportation equipment required to support the Titan III system.

This is a summary of fuel related problems encountered with fuel systems particularly during the past 5 years. The combined efforts of systems engineers and fuel technologists to overcome them are stressed. Problems associated with chemical impurities such as sulfur and chlorine compounds are discussed and comments made upon the effects of particulate matter and free water. Further problems associated with lubricity of fuels are included and some reference to fuel additives. The effects of some hydrogen treated fuels on synthetic rubber is outlined, also the development of equipment to operate at high fuel temperatures and on a wide range of petroleum distillates.

The poor performance of some high purity jet fuels appears to be related to polar compounds in the fuel and not to viscosity, volatility, or sulfur and nitrogen compounds. Surface active additives such as corrosion inhibitors markedly improve lubricity. Results of laboratory tests correlate well with the field experience, where sticking fuel controls and pump wear at high temperatures have been reported. Highly refined fuels developed to meet new standards of thermal stability or purity are generally poor in lubricity compared with conventionally refined fuels and may require a lubricity additive to satisfy advanced fuel systems.

The effect of the flight environment on the severity of the lubrication requirements of the Pratt & Whitney candidate SST engine is reviewed and compared with current commercial turbofan engines. The characteristics of currently available lubricants are examined. The deisgn features of the SST engine aimed at reducing lubricant system stress are discussed. The conclusion is drawn that several type II oils currently available will meet the requirements established by the P & WA SST engine.

The use of pyrotechnic devices in missiles and space vehicles creates a hazardous environment for equipment. Several reported flight anomalies concurrent with the separation event prompted Lockheed Missiles & Space Co. to devote considerable effort to establish methods of treating pyrotechnic shock. An extensive ground testing program included activation of the vehicle’s pyrotechnic systems and subsequent measurement of the shock. Several methods of improving confidence in equipment performance during pyrotechnic shock by means of electrical modifications, shock mounting, and testing were investigated. In addition to treatment of present shock problems, a program was initiated to reduce the pyrotechnic shock levels in the vehicle by redesigning the booster separation joint. Several methods of achieving a qualification testing system for equipments is included in the discussion of the system and specification which LMSC presently uses.

As an alternative to the normal mode approach to the dynamics and controls analysis of flexible aerospace vehicles, the analysis of bending vibration is being studied in terms of the distributed system concepts of propagation and reflection. A relationship is developed between the vibration equation of motion and the propagating wave equation. Transmission matrices, including the effects of shear compliance and rotary inertia, are developed for uniform beam segments. Through a transformation technique, the local state variables are changed to characteristic variables of the beam permitting factorization of the solution into propagation and end-effect matrices. The technique is applied to a cascaded or step beam structure and a beam structure combined with a damped spring mass sloshing model. The advantages and disadvantages of the distributed parameter transmission matrix approach are investigated and the use of this approach for the dynamic analysis of aerospace vehicles is evaluated.

An understanding of the errors associated with the measurement equipment is essential to making correct conclusions about the characteristic of the physical process being measured. This paper discusses the errors associated with analog data reduction equipment. The specific items covered are ordinary and cross-spectral density analyzers; auto-and cross-correlation analyzers; and ordinary and joint probability density analyzers.

This paper discusses the future of systems effectiveness and cost effectiveness analysis in the sequential phases of the life cycle of a weapon or support system. System and cost effectiveness analysis should be developed to be a useful aid to decision making by all participants to a program. Models and supporting data must present total system effectiveness which will cover the operational period of the weapon and total cost analysis which will embrace the acquisition period as well. Also discussed is the application of cost effectiveness analysis by program phases such as during conceptual formulation, contract definition, and during the acquisition period of the weapon system. Cost effectiveness and system effectiveness analysis is an evaluation tool which is an aid to decision making by the government and contractor throughout the life cycle of a weapon or support system.

The primary objective of the Navy's System Performance Effectiveness (SPE) program is to provide tools and techniques necessary for the application of the newly evolved systems effectiveness discipline to the acquisition process for Naval equipment. This discipline attempts to relate design and its associated resource penalties to mission accomplishment while requiring the employment of systems engineering techniques to system development. Extensive Navy efforts in the development of analytic techniques, system design concepts, and system support concepts are briefly described. Areas covered will include microelectronics and packaging uniformity. Brief case histories will illustrate progress to date.

The role of military worth in defense decisions is discussed . Military worth is defined in terms of military utility, system effectiveness, military effectiveness and system cost. These concepts are defined and examples are developed illustrating these definitions. Military effectiveness is defined to include both military utility and system effectiveness. Both these properties, since they are both influenced by uncertainties, should be made subjects of assurance activities during the concept, definition, acquisition and operational phases of the life of a weapon system.

The aeroacoustic pressure loading due to jet and rocket engines and boundary layer turbulence is discussed. The response of structures to these loadings is considered, and many methods of analysis are examined. An evaluation of the labor involved and the resulting accuracy of each method is made. The study shows that the most complete and detailed analysis does not often give the most accurate result, and that more approximate methods can give as comparably accurate estimates of response with far less investment of time and labor.

A decompression chamber for testing automotive diesel engines at simulated altitudes up to 12,000 ft is described. Results obtained on seven naturally aspirated and one turbocharged diesel engine are discussed in relation to the day-to-day correction of engine performance and to site rating of engines. Comparisons are made between experimental results and existing correction methods, and modifications or replacements of the latter are suggested. Results are assessed in terms of the correction method proposed in SAE standard J816. Attention is drawn to the different bases which may be used in correcting engine performance (for example, constant fuel delivery or constant exhaust smoke density) and the need to consider changes of exhaust smoke density or fuel consumption depending on the correction basis chosen.

An engine is sensitive to its fuel and lubricant. This suggests such problems as wear and deposits, and the modifying conditions of environmental effects which cause cold starting and vapor lock. Another environmental condition not often considered is altitude. This paper discusses very briefly a test facility at Aberdeen Proving Ground that can be used to evaluate the full load performance of an engine at varying altitudes. Altitudes of 12,000 ft can be simulated with a 150 hp engine while maintaining temperatures from −65 F to +120 F. Results for six engines operated in this facility are presented. These engines are all military engines but most have commercial counterparts. Data show the advantage of turbocharged engines over naturally aspirated engines. However, unless turbocharger is properly matched to engine and environment, gains are negligible.

Several examples are presented where x-ray stress measurements were made with a portable unit. The examples include the measurement of stresses in a welded rocket motor case (maraging steel), heat-treat stresses in a machined part (7079-T611), and stresses in a spot-welded panel (Ti-8Al-IV-1Mo). Each application emphasizes the advantages of stress analysis by x-ray diffraction by the portable method. For the spot-welded panel there is a direct comparison of x-ray diffraction stress measurements and stress measurements by the compliance method. The results show good agreement between the two methods.

A control system requirement is defined for an advanced direct lift engine designed for a typical Mach 2 fighter aircraft. The characteristics of the control system (performance, weight, reliability and maintainability, cost) are shown to be predominantly a function of the degree of simplicity of the control system requirements and somewhat less a result of the mechanization employed to meet those requirements.

This paper reviews various environments established by the aircraft gas turbine itself, by the aircraft, and by new aircraft engine specifications within which fuel and control systems must operate. Emphasis is on the design requirements placed on controls to assure satisfactory operation in these environments. The influences on design choices and the demands for special testing are discussed for several components. As its objectives, the paper identifies specific areas which may prove troublesome as controls are designed to meet the new requirements. Recognition of potential problem areas is suggested as a first step toward successful design.

Discipline in an airlines organization is essential to the providing of safe, economical air transportation. Such discipline is reflected in leadership, sound organization, firm company policies, professional ability and standards, and a logical and efficient working group. American Airlines is implementing three basic programs in the flight performance area in an effort to reduce risks: centralized flight training, line flying checks in the hands of Flight Standards superintendents, and routine surveillance of operations by use of flight performance recorders and accompanying computer programs.