Experimental measurement of optical angular deviation caused by atmospheric turbulence and refraction
Amplitude and frequency measurement of random position fluctuation of stationary laser optical source due to atmospheric turbulence
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Amplitude and frequency measurement of random position fluctuation of stationary laser optical source due to atmospheric turbulence
Equilibrium and nonequilibrium stagnation point shock layer radiation in simulated planetary atmospheres of varying composition
Radiation patterns and gains measured for short backfire antenna as function of antenna dimensions
Statistical reduction of satellite effective radio cross section of reflected radio signal power measurements made on Echo I passive satellite
Measurement of ion velocity distribution in plasma stream of pulsed coaxial accelerator agreeing with computation from momentum transfer and mass flow measurements
Rocket measurement of secondary electron energy distribution in aurora, employing 180 degree electrostatic deflection analyzer
Cyclic incident radiation method for measuring thermal emittance and absorption properties of metals at cryogenic temperatures
Thermionic work functions and desorption energies for oxygen on polycrystalline W, Mo and Re filaments, discussing oxygen pressure and filament temperature
Gaseous reactant combustion simulation of dimethylhydrazine and hydrazine fuel system for nonequilibrium expansion studies
Solar absorptance, total hemispherical emittance and absorptance/emittance ratio for metals at cryogenic temperatures measured simultaneously with sinusoidally perturbed incident radiation
Catalytic surface recombination for measuring diffusion coefficients of atomic oxygen
Methane and ethane hydrate number measurement, alleviating liquid water occlusion and evaluating pressure effect
Argon II line transition probabilities, observing UV spectral region, upper energy levels and temperature differences
Energy decay and spectra measurements of grid-injection turbulent flows
These direct measurements are in fair agreement with computations made using a program which considers both basic cosmic ray atmospheric physics and the focusing effect of the earth's magnetic field. These measurements also agree with those made at supersonic jet aircraft altitudes in Rb-57 aircraft. It is concluded that experiments and theory show that the doses received at conventional jet aircraft altitudes are slightly higher than those encountered in supersonic flights at much higher altitudes.
Airborne 2.25-cm wavelength radar backscatter measurements of low-wind-speed sea conditions were obtained off the coast of Texas in January 1971. These data are compared with unpublished NASA 2.25-cm backscatter measurements recorded over the Atlantic in 1970. The two data sets were in general agreement and supported results previously reported by other authors which showed the absence of a saturation effect at this wavelength. Analyses of these data using computerized clustering techniques indicated that a wind speed measurement accuracy of 5-7 knots is an operational potential.
Results are presented of firing a Nike rocket against a backstop for the purpose of obtaining pressure fluctuations in the rocket case and determining their relationship to structural vibrations of the case. Special care was required to obtain these pressure fluctuations because of the much higher static pressure generated in the rocket. Very small pressure fluctuations within the rocket case can cause significant vibration levels. A previously observed high frequency was shown to decrease with time before completely disappearing at about 1 second of burning time. The vibration of the case itself is probably related to the longitudinal structural modes at frequencies below 500 Hz and is dependent on local structural conditions at frequencies above this value.
The Titan-Centaur was launched from Kennedy Space Center on February 11, 1974 at 0948 eastern daylight time. Ground level effluent measurements were obtained from the solid rocket motors for comparison with NASA diffusion models for predicting effluent ground level concentrations and cloud behavior. The results obtained provide a basis for an evaluation of such key model inputs such as cloud rise rate, stabilization altitude, crosswind growth, volume expansion, and cloud trajectory. Ground level effluent measurements were limited because of changing meteorological conditions, incorrect instrument location, and operational problems. Based on the measurement results, operational changes are defined. Photographs of the ground exhaust clouds are shown. The chemical composition of the exhaust gases was analyzed and is given.