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A simple and reliable concept for the collection, processing, disposal or storage of human waste products has been developed for application under conditions of weightlessness. Psychological acceptance is achieved by utilization of a hardware design permitting conventional earth-like procedures. Bag type containers are not used for collection and storage, thus manual handling of waste products and storage containers is not required. The system is capable of handling urine and fecal waste as well as Yomitus and food debris. The solids are vacuum dried to permit bacteriostatic storage and urine can be jettisoned to space.

Experimental results obtained with a continuous culture system for the cultivation of Hydrogenomonas eutropha for waste management in a life-support system indicate that a reliable and stable system can be designed under the present state-of-the-art. The present system provides for control of hydrogen, oxygen, carbon dioxide, pH, cell density, temperature, urea, and ammonia during growth. The culture system design is adaptable to operation in a zero-gravity field, and should be adaptable to integration with proposed water electrolysis and product recovery systems for waste management in an overall life support system.

An oxygen-producing water electrolysis cell with phosphoric acid electrolyte can operate on the water vapor in recirculated cabin air and accomplish concurrent dehumidification. The development of the concept over the past 3 years involved research to define the components of electrode overvoltage and design analysis to provide a small, lightweight unit to compensate for the electrolysis power. Theoretical equations based on electrochemistry, fluid dynamics, and heat and mass transfer correlate with the observed steady state operation obtained in extended testing of experimental cells for over 1000 hr. Data on electrode life, gas purity, and voltage characteristics combined with size, weight, and power estimates indicate that the new concept would be competitive with other methods of oxygen generation for advanced space missions. The recent satisfactory performance of a prototype module in an extended test of over 1000 hr is reviewed.

A novel prototype waste management unit for the collection, sampling, drying, and storage of fecal wastes in a life-support simulator, or aerospace flights has been designed, developed, and tested. The unit collects the feces, which are subsequently air dried at ambient temperature and pressure, and stored. The unit is designed for use in a weightless environment yet has the convenience of operation of an ordinary terrestrial toilet. Other design features include measures to prevent fecal contamination or odors from entering the space cabin, low power requirements, and minimum loss of cabin air overboard. Weight of the unit is about 50 lb.

The requirements for V/STOL aircraft introduce unique structural problems and make more severe those common to conventional vehicles. Propulsion modes requiring increased thrust during hover and their relative airframe locations are responsible for the major portion of the associated problems. Those problems which require first-order attention, such as design philosophy for fan-in-wing configurations to obtain optimum structural design are discussed. The solution of acoustic environment problems, such as noise attenuation and acoustic fatigue, are investigated. Likewise, the study of thermal problems, both internal and external, and their effect on structure is presented. The problem of debris damage due to the propulsion environment at ground hover is discussed showing the potential energy level of debris. Finally, the importance of structural weight/cost effectiveness is shown for V/STOL aircraft.

Atmospheric turbulence measured at low altitudes over rough terrain in high wind conditions is shown to be more severe than the turbulence previously measured in thunderstorms. The military requirement for large bomber and logistic airplanes to operate at low level thus will result in large weight and performance penalties unless some means to reduce structural loads is employed. By use of power spectral density techniques, it is shown that loads in low level turbulence can be reduced on large airplanes with an adequate stability augmentation system. This load reduction is sufficient to insure that large aircraft operating at low level will not be unduly penalized in performance.

This discussion summarizes the highlights of the C-141A airplane program, emphasizing fatigue, damage tolerance, and static strength considerations philosophically and in considerable detail where design criteria are involved. Dynamic considerations are also included insofar as the structural design of the airplane was affected thereby. Finally, some significant differences in criteria requirements between the C-141A and the C-5A are identified together with their expected impact on structural design.

The U. S. Army CH-47A Chinook is a transport helicopter developed by Boeing. Major considerations in the development of its structural integrity are discussed in this paper. Included is a description of fatigue analysis techniques which were developed to insure safe life of its critical components. This technique includes a mission profile, component fatigue strengths, use of top-of-scatter flight loads data, use of Miner’s rule of cumulative damage, and evaluation of possible anomalies on fatigue strengths and flight loads.

This paper discusses those materials that appear to offer the most promise for structural usage in high altitude/high temperature vehicles. Various aluminum-, titanium-, beryllium-, iron-, and nickel-base alloys are compared with respect to density, short time tensile, creep, fatigue, and fracture toughness properties. Their corrosion and stress corrosion characteristics as well as long time stability are discussed.

The advantages of an F-4C beryllium rudder are presented (torsional stiffness increased 500%, weight reduced 46%). Its analysis, design, fabrication, and ground tests discussed, and a fail-safe flight test program defined. Other potential F4C beryllium structural components within the state-of-the-art are reviewed and potential weight savings estimated.

The results of pump loop testing 50 candidate supersonic transport (SST) hydraulic fluids were presented to the May 1965, SAE Aerospace Fluid Power Systems and Equipment Conference in Los Angeles. This paper presents the results of subsequent pump loop testing of nine new fluids or compoundings. A discussion of simulated fire-resistance testing is also included. Results of pump loop testing to date indicate that four specific types of fluids are considered the best SST hydraulic fluid contenders. They are: chlorosilicone, mineral oil, perfluoroalkyl, and polyaryl.

High-temperature electrical materials presently available for application in the 500-1600 F range have been evaluated for advanced Rankine cycle systems and other high temperature applications. Magnetic materials for high saturation, low loss use include cobalt-iron and doubly oriented silicon-iron alloys. Nivco alloy (72w/o Co, 23w/o Ni and other alloying elements) has the highest creep resistance above 1000 F of all magnetic materials suitable for mechanically stressed applications. Inorganic insulations for magnet wire, flexible sheet, interlaminar coatings, potting compounds, and rigid or molded parts are discussed. Inconel-clad silver and clad and unclad dispersion strengthened copper electrical conductors offer the best performance in stressed and unstressed applications respectively.

This paper presents information compiled on the temperatures encountered by reentry and high performance aircraft, the metals and dielectrics useful for antennas and radome applications, and the effects of high temperature on the performance of these assemblies.

Coated refractory metals, coated and alloyed graphites, hafnium-tantalum alloys, refractory borides, and stabilized zirconias are considered for the 3600–4000 F high-velocity air environment. Only refractory borides and stabilized zirconias are indicated as offering long duration and reuse capabilities for such high-temperature utilization. Iridium, as coatings on substrates of either graphites or refractory metals, appears attractive for shorter times (less than 1 hr). Environmental evaluation and the need for a theoretical framework to enable the prediction of performance data for such materials are indicated to be major problems facing users and suppliers.

Candidate hydraulic fluids for systems which operate under extreme conditions vary considerably in properties and capabilities. Some compromise in fluid properties may be required but such compromise must not affect system reliability, safety and performance. This paper reviews the properties of the newer hydraulic fluid classes and their relation to maximum performance.

Considerations governing the selection of superalloys and refractory alloys for the fabrication of high-performance reentry vehicles are discussed. Oxidation resistant coatings were evaluated to determine their capacity to protect faying surfaces. The performance of the R-512A coating under simulated reentry conditions is reported.

This paper presents the results of a developmental program designed to determine physical and environmental effects on the response of balsa wood as an energy dissipator. Specifically, the effects of moisture content, density, temperature, and pressure on the energy dissipating characteristics of balsa wood are presented. It is shown that the response of balsa wood is critically dependent on physical and environmental conditions, and that the energy dissipating capacity of the material increases significantly under certain combinations of these conditions.

A series of new magnesium base casting alloys has been developed for high stress aerospace applications. The alloys are readily castable, have high strength, good ductility, and excellent fatigue properties. They show little or no tendency to microporosity and provide distinct advantages in control of quality. The alloys are based on the application of a new principle of heat treatment involving internal precipitation of hydride. Described in detail are ZE63A and ZE63B alloys.

TWO new ablative materials, designated SLA-741 and SLA-561, have been developed by Martin Marietta for Mars Lander thermal protection. The density range of these ablators is 0.18-0.22 g/cc and is substantially lower than that of other types of low density charring ablators. Plasma arc testing conducted in a simulated Mars atmosphere has established that SLA ablators are considerably more efficient than conventional ablators such as filled silicone, low density nylon-phenolic, or corkboard and that they form sturdy, erosion resistant chars.

New mechanical property data on the 62% Be, 38% Al alloy, “Lockalloy,” are presented and compared with other lightweight structural metals. The new data consist of tentative design properties for annealed sheet and provide a summary of its characteristics and properties. Material comparisons are made on the basis of gross fracture stress, an elastic weight index for compression critical structures, and on the basis of tensile strength/density and tensile yield strength/density ratios as a function of temperature for tension critical structures.