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Template is used for evaluation of the dynamic characteristics and accuracy of the plotter. It has a profile composed of surfaces parallel to and at known distances from a reference plane, plane, the diverse surfaces being connected by slopes of known angles and blended by cylindrical developments of known radii.
Propulsion efficiency tests of FLOX and ethane- methane space storable propellant blend
Space storable hydrocarbon fuel blended FLOX propellant performance with coaxial injector including characteristic velocity, chamber geometry, pressure and heat flux distribution
Mechanical process produces dispersion-strengthened metal alloys. Power surface contamination during milling is removed by a cleaning method that involves heating thin shapes or partially-compacted milled powder blends in hydrogen to carefully controlled temperature schedules.
Faint meteor ablation processes, presenting evidence of solid consistency prior to atmospheric entry, vaporization, wake blending and trails
Absorption strengths of j-manifolds in R branch of Jupiter atmosphere methane band, discussing fine structure blending
Predicted and measured aerodynamic characteristics for blended delta-wing orbiter at hypersonic speeds
Improved cadmium electrode substrates with precisely controlled microstructures for possible use in aerospace nickel-cadmium cells were prepared. The preparative technique was a powder metallurgical process in which a fugitive pore-former and a nickel powder were blended, then isostatically compacted, and subsequently sintered. Cadmium electrodes prepared from such substrates were cycle tested using an accelerated tortuous test regime. It was discovered that plaques of 60% or 80% porosity prepared with a 25 micron pore-former were better than state-of-the-art electrodes in terms of efficienty and/or mechanical strength. The 60% structures were particularly outstanding in this respect in that they had efficiencies only 5-10 percentage points lower than state-of-the-art electrodes and vastly superior mechanical properties. This added strength was observed to eliminate cracking and physical degradation of the electrodes during processing and cycling. The cadmium electrodes prepared from the 80% porous substrates proved to be the best electrodes made during the course of the work from the point of view of highest efficiency. Three-point bend tests were used to measure mechanical properties of the plaques produced and also as a general characterization tool. In addition, the BET surface areas of selected specimens was determined. The SEM was used for judging microscopic uniformity and quantitatively determining the induced pore size and various other fine structures in the substrates. The technique of X-ray radiography was used to follow the bulk uniformity of the substrates at various stages of their processing.
An investigation was conducted to determine whether a nickel - 2-volume-percent alumina dispersion-strengthened material with a fine, uniformly distributed dispersoid could be produced, which was equivalent in short time tensile strength to commercially available thoriated sheet materials. Comminution and blending with a modified triple stirrer attritor and a hydrogen and vacuum precleaning treatment prior to consolidation were used. A product with a fine dispersoid with an average particle size of 0.04 micron and an interparticle spacing of 0.7 micron was achieved. This material has a 1093 C (2000 F) short time tensile strength of 117 MN/sq m (16 900 psi).
A critique is presented of the lead paper by L.D. Kaplan on infrared radiometry. The following topics are analyzed: the extent to which the desirable thermal resolution of the lower troposphere can be achieved, the effects of complex cloud structure on infrared data, the effective weighting function if linearization is possible, remote sounding from below the atmosphere, first-guess fields and operational techniques to blend satellite infrared data into a mix of data from various meteorological systems, a simple inversion procedure for thermal structure, and problems arising from cloud and haze layers of variable amount and emissivity.
The optimization technique is described which was used in the study for applying modern optimal control technology to the design of shuttle booster engine reaction control systems and aerodynamic control systems. Complete formulations are presented for both the ascent and reentry portions of the study. These formulations include derivations of the 6D perturbation equations of motion and the process followed in the control and blending law selections. A total hybrid software concept applied to the study is described in detail. Conclusions and recommendations based on the results of the study are included.
A method for temperature control of the combustion gases in the peripheral zone of a rocket combustor which would reduce ablative throat erosion, prevent melting of zirconia throat inserts, and maintain high combustion performance is discussed. Included are techniques for analyzing and predicting zoned injector performance, as well as the philosophy and method for accomplishing an optimum compromise between high performance and reduced effective gas temperature. The experimental work was done with a 1000-lbf rocket engine which used as propellants N2O4 and a blend of 50-percent N2H4 and 50-percent UDMH at 100-psia chamber pressure and an overall O/F of 2.0. The method selected to provide temperature control was to use 30 percent of the propellant to form a peripheral zone of combustion gases at an O/F of 1.31 and 2700 K. The remaining 70 percent of the propellant in the core was at an O/F of 2.45 to keep the overall O/F at 2.0.
The Wisconsin far ultraviolet spectrometer aboard OAO-2 observed the wavelength region near 1216 A for 69 stars of spectral type B2 or earlier. From the strength of the observed interstellar L sub alpha absorption, atomic hydrogen column densities were derived over distances averaging 300 pc away from the sun. The OAO data were compared to synthetic ultraviolet spectra, originally derived from earlier higher resolution rocket observations, which were computer processed to simulate the effects of absorption by different amounts of hydrogen followed by the instrumental blending.
The OAO-2 satellite has been used to obtain far ultraviolet scans of six early-type supergiants. The data reveal the presence of a distinct, broad absorption feature centered near 1720 A. This feature is unique in that it remains essentially constant in strength, breadth and central position over the spectral type range B0 I to A2 I. The feature also appears in the spectrum of the B-type shell star beta Tauri, with a strength comparable to that observed for the supergiants. It appears weakly, or not at all, in the B and A main sequence spectra we have examined. The hypothesis that the feature is due to a fortuitous blend of intrinsically strong lines arising primarily from the ground configurations of abundant metallic ions is discussed in detail.
Hologram is constructed by taking number of digitized sample points and blending them together to form ''continuous'' picture. New system selects better set of sample points resulting in improved hologram from same amount of information.
The high subsonic and transonic characteristics of fighter aircraft and the factors affecting aerodynamic boundaries, such as maximum obtainable lift, buffet onset, pitchup, wing rock, and nose slice are discussed. Investigations were made using a general research configuration which encompassed a systematic matrix of wing design parameters. These results emphasized the sensitivity to section and planform geometry at the selected design point. The incorporation of variable-wing-geometry devices in the form of leading-edge slats or flaps was shown in a number of flight and wind-tunnel studies to provide controlled flow over a wide range of flight conditions and substantial improvements in maneuver capabilities. Additional studies indicated that the blending of a highly swept maneuver strake with an efficient moderately swept wing offers a promising approach for improving maneuver characteristics at high angles of attack without excessive penalties in structural weight.
The report describes the development and evaluation of an inert simulant for the thermally stable, heat-resistant plastic-bonded explosive HNS/Teflon. The simulant is made by dry blending vinylidene fluoride, melamine and Teflon which when compared has a pressed density and thermal properties corresponding closely to the explosive. In addition, the machinability and handling characteristics of the simulant are similar to the explosive.
The author has identified the following significant results. A reconstituted, simulated color-infrared print, enlarged to a scale of 1:250,000, was used to make a vegetation map of a 3,110 sq km area just west of Fairbanks, Alaska. Information was traced from the print which comprised the southeastern part of ERTS-1 scene 1033-21011. A 1:1,000,000 scale color-infrared transparency of this scene, obtained from NASA, was used along side the print as an aid in recognizing colors, color intensities and blends, and mosaics of different colors. Color units on the transparency and print were identified according to vegetation types using NASA air photos, U.S. Forest Service air photos, and experience of the investigator. Five more or less pure colors were identified and associated with vegetation types. These colors were designated according to their appearances on the print: (1) orange for forest vegetation dominated by broad-leaved trees: (2) gray for forest vegetation dominated by needle-leaved trees; (3) violet for scrub vegetation; (4) light violet denoting herbaceous tundra vegetation; and (5) dull violet for muskeg vegetation. This study has shown, through close examinations of the NASA transparency, that much more detailed vegetation landscape, or ecosystem maps could be produced, if only spectral signatures could be consistently and reliably recognized and transferred to a map of suitable scale.