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This paper describes the precision casting of Nicrosil and HH alloy hot sizing dies designed for forming close tolerance titanium alloy parts at high temperatures. A modified Shaw Process molding technique, with Nalcast crushed fused silica refractory grain is used to cast the dies to net dimensions. Foundry test results show that a variety of part shapes can be successfully formed to net dimensions on the cast dies. The use of precision cast dies will also achieve substantial savings by eliminating costly and time-consuming machining.

The general history of the use of high-performance plastic reinforced composites is traced. An example of the projected economic impact of weight savings possible through the use of composites for a commercial aircraft, and the elements and their current status of reinforced plastic composites research are presented. Projections of composite research in the next 3–5 years predict, in comparison to current aircraft aluminum alloys, an increase in specific strength by a factor of about 5, an increase in specific modulus by a factor of about 3, and a 300–500 F increase in thermal capability. Projection for the 5–10 year period emphasizes that increased strength is the area of greatest potential.

Seven billion pounds of resins, reinforcing agents, and fillers are estimated to be in annual use today in reinforced plastics, or composite, applications. Their total value to industry is about 4 billion dollars. Data are presented on the potential which exists for producing significant advances of at least two-fold, as opposed to relatively minor improvements in sheet materials such as steel, aluminum, and titanium. This paper presents a review of this surprisingly super market for reinforced plastics with emphasis on management participation.

The author discusses the need for cryogenic temperature resistant plastic materials in the space program. The selection of a plastic material for cryogenic application is dependent on the cryogenic fluid with which it will come in contact. Problem areas discussed are insulation of cryogenic materials, adhesives used on plastics, use of seals and gaskets, and the expulsion of cryogenic propellant in a zero gravity environment. Through this type research appears to have limited application in the aerospace industry, future generations may benefit materially from the work being done.

The deformation processing of beryllium is discussed with respect to mechanical properties, economics and manufacturing considerations. Production techniques using closed impression die forging, extrusion and ring rolling have been established for manufacture of wrought beryllium shapes which include discs, hemispheres, cylinders, shafts and rings. The metallurgical aspects of the response of beryllium to thermo–mechanical treatments are presented. Current activity includes development of procedures for manufacture of large conical shapes with height–to–diameter ratios greater than one.

Space mission reliability includes both space vehicle and ground support systems reliability as factors, and it is often charged that ground systems are treated as “poor cousins” in the allocation of reliability program effort. Factors which determine reliability requirements, the physical meaning of these requirements, and the characteristic problems involved in meeting them are compared for space and ground systems. It is shown why the required reliability should be achieved on ground systems at a lower cost than on space systems.

The acquisition of direct support facilities for Space and Weapon Systems has generated many problem areas during programs that required facilities design, prototype testing and construction concurrent with missile/launch vehicle research and development. This paper outlines some of these problems in the areas of facilities concepts, design, construction, operation, and maintenance; identifies the causes and indicates action taken to date by both government and industry to systemize the management of future Space and the Weapon System development. The urgency and importance of the applicability of the elements of training and personnel, logistic support, technical data, and support equipment are also discussed.

For efficient, flexible, and high-quality checkout, the capabilities and limitations of checkout equipment must be considered in the spacecraft design. Ideally, spacecraft and GSE should be designed as a working entity, with ground rules established for their concurrent development. Emphasis must be placed on systems engineering to establish and maintain compatibility. Some insight into the importance of GSE in meeting space objectives is presented together with an analysis of the degree to which spacecraft design is influenced by GSE.

Automation of high production, high complexity, and high speed testing is often of obvious worth. The use of automation by the “popular” space programs has developed techniques that warrant consideration of systems previously considered to be incompatible with automatic testing, either because of testing difficulty or cost. Manual testing is still a requirement in the developmental testing phase of many programs. It is also an established requirement in many factory level tests. The complete systems approach involving the total mission requirements for factory through launch (or other use) sequence will enable the logical selection of the correct testing elements, both automatic and manual.

A procedure is outlined which identifies the influencing factor which must be considered when formulating a space support plan. The plan is described as the “top document” used by both management and customer to guide the support aspects of a program. A systems approach to arrive at the Support Plan is presented along with examples of analysis techniques used to perform system trade-offs.

In the past, AGE management had an individual role in the development and acquisition of a weapons system. With the advent of the Air Force systems management techniques, in implementation of new DOD directives, management of AGE is now part of the total systems management package. The Air Force approach is contained in the 375 series regulations and implemented by the Air Force Systems Command 375 Manuals. Primarily, this paper describes the application of total systems management technique in the definition, design, development, and production of a weapon system. These new management procedures provide the technical basis for the establishment of three baselines, namely, Program Requirements Baseline, Design Requirements Baseline, and Product Configuration Baseline, as well as the development of specifications and control of engineering changes.

In the author's view, present method of managing the acquisition of technical facilities in the traditional Air Force civil engineering manner is obsolete and is steadily proving more and more inadequate in the face of ever expanding technology. A system of management based on the techniques developed in system engineering and outlined in the Air Force Systems Command Manuals in the 375 Series is advocated as a course of action for the future.

Studies were performed to determine which environments are germane to simulation during structural verification tests on future aerospace vehicles. Missions of proposed orbital and space vehicles and associated environmental conditions are defined. Effects of both natural and induced environments on structures are discussed and those necessary for simulation are presented. Results conclude that critical environmental conditions are experienced during exit from and entry into the earth's atmosphere. For the most part, the effects of the space environment are relatively insignificant on vehicular structures. Present environmental structural testing capabilities for orbital and space vehicles are presented and future development needs predicted.

Booster structure is subjected during the boost phase to a number of dynamic environments which may affect the integrity of the overall structure. To perform a meaningful dynamic load or stability analysis, an accurate prediction of the dynamic characteristic of the structure is required. Due to the complexity of Titan III, it was felt that the analysis by itself was not sufficient to guarantee a successful flight. A 20% dynamically scaled model of the Titan III was constructed and a vibration survey conducted. Comparison of the results indicates in general a good correlation of the test and the analytical data in the first three lowest pitch, yaw, and longitudinal modes.

An improvement to the thin walled tank in the higher load region is developed by the addition of a prestressed jettisonable shell. Capability of the tank includes post-wrinkling strength in bending. Comparison is made with an efficiently stiffened tank, using for example a liquid hydrogen tank 10 ft in diameter. The results of the study show the total effective weight of the minimum gage pressurized tank with a prestressed jettisonable insulating shell to be less than one-half the weight of an insulated stiffened tank for a wide range of loading.

The influence of the integrated, rapidly changing environmental conditions, from launch through orbit to entry and recovery, on the structure and thermal protection systems of advanced space vehicle systems is defined. Two vehicle systems are considered: a space exploration system employing a vertical takeoff expendable launch vehicle, ballistic entry vehicle, and vertical landing; and an orbital operations system employing reusable stages with horizontal takeoff and landing capability. Data are presented on the mission requirements, design criteria, structural characteristics, and pacing technology problems for each system.

The problems associated with the management of aerospace ground equipment can be solved by a program designed to ensure proper recognition by contractor and customer management. Such a program requires sweeping changes in the categories of administration, engineering, configuration management, contracts, and data. Implementation will ensure an adequate appreciation of AGE requirements by management and furnish positive and effective guidance to the design engineer. Most important, the AGE program will provide uniform equipment configuration, adequate contracts, and useable engineering data.

The problem of achieving safety in orbital and space vehicle structures is essentially the problem of obtaining a structural reliability of “one” in the engineering sense, not necessarily mathematical. This problem is not unique to space vehicle structures; manned aircraft also have this objective, and the “basic elements” that determine the structural safety of such vehicles are well established. A number of specific structures on the Mercury and Gemini spacecraft are reviewed to illustrate the considerations given to structural safety (including “fail safe” and “fracture tolerant” design) by the utilization and extension of these “basic elements.”

Problems in environmental testing of orbiting and space vehicle structures are primarily caused by the limitations of the ground test facilities in providing adequate simulation of the operational environment. This paper will give an account of the specialized environmental simulation techniques developed and the analysis methods used to supplement the facility capabilities for the environmental test program of the Lunar Excursion Module (LEM).