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  • Other Sources  (486)
  • AIRCRAFT PROPULSION AND POWER  (270)
  • SOLAR PHYSICS  (216)
  • Chemistry
  • Life and Medical Sciences
  • 1975-1979  (486)
  • 1950-1954
  • 1945-1949
  • 1977  (486)
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  • 1975-1979  (486)
  • 1950-1954
  • 1945-1949
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  • 1
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    Aircraft engines (1977)
    In:  CASI
    Details
    Publication Date: 2006-01-16
    Description: Thrust and weight requirements of aircraft engines in general are discussed. The characteristics and operating principles of various types of air breathing and rocket engines are described.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Soviet Aircraft and Rockets (NASA-TT-F-770); p 81-139
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  • 2
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    Enhancement of solar heavy nuclei at high energies in the 4 July 1974 event (1977)
    In:  Other Sources
    Details
    Publication Date: 2011-08-17
    Description: Relative abundances of energetic nuclei in the July 4, 1974, solar event are presented. The results show a marked enhancement of abundances that systematically increase with nuclear charge numbers in the range of the observation (Z between 6 and 26) for energies above 15 MeV/nucl. While such enhancements are commonly seen below 10 MeV/nucl, most observations at higher energies are found to be consistent with solar-system abundances. The energy spectrum of oxygen is observed to be significantly steeper than most other solar events studied in this energy region. It is proposed that these observations are characteristic of particle populations at energies of the order of 1 MeV/nucl and that the anomalous features observed may be the result of the high-energy extension of such a population that is commonly masked by other processes or populations that might occur in larger solar events.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 55; Dec. 197
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  • 3
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    Faraday rotation transients observed during solar occultation of the Helios spacecraft (1977)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Keywords: SOLAR PHYSICS
    Type: AFGL Contrib. Papers to the Study of Travelling Interplanetary Phenomena(1977; p 63-75
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  • 4
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    Computer solutions for studying correlations between solar magnetic fields and Skylab X-ray observations (1977)
    In:  Other Sources
    Details
    Publication Date: 2011-08-17
    Description: A method is described which correlates the NASA-Marshall Space Flight Center (MSFC) Image Data Processing System (IDAPS) and MSFC magnetograph data to X-ray and H-alpha observations from the Skylab mission. Solutions of Laplace's equation in three dimensions, based on the magnetograph data, are convolved with observed X-ray and H-alpha regions. Matched filtering (template matching) provides a best fit of the observed X-ray regions to the computed total magnetic vector magnitude between 10,000 and 15,000 km above the photosphere.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 53; July 197
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  • 5
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    The spiral configuration of sunspot magnetic fields (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Distributions of circularly and linearly polarized intensities are computed using an analytical magnetic field model for an isolated sunspot, and these intensity distributions are compared with observed intensities in all Stokes parameters in the 5250-A line measured with the Marshall Space Flight Center's vector magnetograph. The qualitative agreement between measured and calculated linearly polarized intensity distributions is discussed with regard to implications as to the configuration of the transverse magnetic field of the isolated sunspot.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 53; July 197
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  • 6
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    A search for a turbulent-free region in the solar transition zone (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: A search for a turbulence-free transition-zone region was conducted. The data used were spectra recorded by a slit spectrograph on Skylab. It was found that the nonthermal turbulent motions are smallest in certain active regions and quiescent prominences. The spectra of one such region, a quiescent prominence, are discussed. The nonthermal turbulence in the region is between about 2 and 7 km/s. Therefore, the widths of lines emitted by transition-zone ions are determined primarily by the ion temperature. To within the experimental error, temperatures derived from the line widths are equal to the temperatures of maximum emitting efficiency obtained using the ionization equilibrium calculations of Jordan (1969).
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal; vol. 216
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  • 7
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    XUV spectra of the 1973 June 15 solar flare observed from Skylab. II - Intersystem and forbidden transitions in transition zone and coronal ions (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal; vol. 215
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  • 8
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    On the problem of density diagnostics for the EUV spectrum of the solar transition zone (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Spectral-line ratios that may be used to determine the electron temperature and density in the solar transition zone and corona are identified. The problem of interpreting the intensity ratios of C III lines observed in Skylab EUV limb spectra is considered. It is shown that the intensity distribution with height above the solar limb of the 1176-A C III lines is different from that of the 1909-A C III lines in the Skylab spectra, suggesting that model atmospheres must be folded into the C III calculations for proper interpretation of the data. Possible reasons for the differences in the intensity distributions and widths of the 1176-A and 1909-A lines are discussed along with an application to the analogous lines of Si III.
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 58; 1-2,; June 197
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  • 9
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    XUV spectra of the 1973 June 15 solar flare observed from Skylab. I - Allowed transitions in chromospheric and transition zone ions (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal; vol. 215
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  • 10
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    Magnetic holes in the solar wind (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: An analysis of high-resolution magnetic field measurements from the Goddard Space Flight Center magnetometer on Explorer 43 showed that low magnetic field intensities (less than 1 gamma) in the solar wind at 1 AU occur as distinct depressions, or 'holes', in otherwise nearly average conditions. These magnetic holes are new kinetic scale phenomena, having a characteristic dimension of the order of 20,000 km. They occurred at a rate of 1.5/d in the 18-day interval (March 18 to April 6, 1971) that was considered. Most magnetic holes are characterized by both a depression in /B/ and a change in the magnetic field direction, and some of these are possibly the result of magnetic merging. However, in other cases the direction, does not change; such holes are not due to merging but might be a diamagnetic effect due to localized plasma inhomogeneities.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; May 1
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  • 11
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    A search for auroral type motions in solar flares (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Because of analogies between auroras and solar flares, and because of well-established motion along auroras (the so-called westward travelling surge), one might expect systematic motion of brightness to occur along flare ribbons. The Sacramento Peak Observatory flare records of 37 double-ribbon solar flares observed from 1968 to 1972 were examined for evidence of such systematic motion, but results of the investigation were negative.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; May 1
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  • 12
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    High resolution spectroscopy of the disk chromosphere. V - Space-time variations observed simultaneously in seven lines (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Time sequence spectroscopic observations of the quiet solar chromosphere along a 200 Mm strip near the center of the disk were reduced to obtain 30 min of data. Oscillations appear in most of the observations in selected photospheric and chromospheric lines, but rarely in continuum observations. At a given point, the oscillations may be prominent or weak, they are never regular in time, and there is no unique relationship between the amplitudes at different heights. There are several examples of granules which apparently excite a burst of short period oscillations. By considering the line shift and intensity variations of all the lines, a working model is derived for the velocity field and related temperature variation.
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 57; 1-2,; May 1977
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  • 13
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    On coronal temperatures, temperature gradients and compositions (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Average solar wind properties at 1 AU either alone or together with the electron density distribution are used to obtain or review some results that relate coronal temperatures, temperature gradients, and compositions. Measured values of the temperature (T) and the temperature gradient parameter are used to find compositions that satisfy the equations used to obtain the results. The total energy equation may be satisfied if the thermal conductivity is reduced by considerable depletions of H(+) in the corona. The hydrostatic approximation (momentum equation) for the electron density distribution appears to require considerable depletions of H(+) in the corona.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 51; Mar. 197
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  • 14
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    Structure of coronal holes from UV and radio observations (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: EUV (Fe XV at 284 A) and radio (at 169 and 408 MHz) observations were made of the coronal hole on May 31, 1973. An inhomogeneous model consisting of hot (a temperature of about 2 x 10 to the 6th K) elements covering 10% of the hole surface surrounded by regions of colder gas (a temperature of about 8 x 10 to the 5th K) is able to explain both observations.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 51; Jan
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  • 15
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    Physical processes determining the chromospheric temperature distribution (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: It is demonstrated that short period acoustic waves appear adequate to heat the low chromosphere in the region just above the temperature minimum, these waves are unlikely to provide sufficient energy to heat the chromosphere above tau-5000 A(normal) less than 10 to the -6th. Calculations also show that the electron density to H density ratio from chromospheric models is too low for the H2 molecule to affect the population of H(-).
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 51; Jan
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  • 16
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    Preliminary analysis of coronal electron content measurements from spacecraft Helios A around first solar occultation (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Steady-state and dynamical features of the electron density distribution in the solar corona emerge from a preliminary analysis of Helios A electron content measurements. There are strong indications that correlations can be established with earth-bound K-coronagraph measurements.
    Keywords: SOLAR PHYSICS
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  • 17
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    The 3s-3p and 3p-3d lines of Mg II observed above the solar limb from Skylab (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal; vol. 212
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  • 18
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    The coronal temperature and nonthermal motions in a coronal hole compared with other solar regions (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The coronal lines Si VIII (1446 A), Fe X (1463 A), Fe XI (1467 A), and Fe XII (1242 A and 1349 A) were observed above the limb over a quiet region, a coronal hole, and two active regions. The lines emitted at temperatures greater than 1 million K; i.e., the iron lines, are not observed in the coronal-hole spectra, so the indication is that in the coronal hole most of the plasma is at a temperature of less than 1 million K. The emission measures and column densities of the lines are derived from available atomic cross-section data, and the results are discussed. The nonthermal velocities in the coronal hole and quiet region are about 20 km/s. The velocities in the active regions are substantially less.
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal; vol. 212
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  • 19
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    Chromospheric limb spectra from Skylab - 2000 to 3200 A (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Chromospheric limb spectra of a quiet-sun region between 2000 and 3200 A recorded by the normal-incidence spectrograph on Skylab are discussed. The spectral resolution is 0.12 A, and the projected slit area on the sun is 2 by 60 arcsec. A list of lines with wavelengths, identifications, and absolute intensities is given for the spectrum recorded at +4 arcsec outside the white-light limb. The intensity behavior outside the limb is shown for lines of the ions C II, Si II, Cr II, Mn II, Fe II, Fe III, Co II, and Ni II. The widths of the intersystem lines of Si II and C II increase monotonically with height above the limb. The full width at half-maximum of the Si II lines increases from 0.034 A at the limb to 0.27 A at +12 arcsec above the limb. The widths of the C II lines increase from 0.17 A at +2 arcsec to 0.31 A at +12 arcsec.
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal Supplement Series; 33; Jan. 197
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  • 20
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    Nonlinear Alfven waves in high-speed solar wind streams (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: A nonlinear proton distribution function that is an exact stationary solution of the nonlinear Vlasov equation and Maxwell's equations and which supports a single nonlinear transverse Alfven (ion cyclotron) wave that is circularly polarized and nondispersive is proposed for most of the observations during high-speed solar wind streams. This nonlinear distribution removes the strong Alfven wave instability, inconsistent with the persistence of the observed proton distribution functions in high-speed streams, found by the linear stability analysis. Model temperature anisotropies and drift velocities of the two spatially inhomogeneous bi-Maxwellian components are consistent with typical proton velocity distributions measured in high-speed streams at 1 AU. Two derived relations for each of the wave number and the phase velocity of the wave are obeyed within experimental uncertainties by two typical proton measurements. Our model also predicts that the alpha particle bulk flow velocity exceeds the proton particle bulk flow velocity, as is observed.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; Feb. 1
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  • 21
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    Approximations for proton excitation of coronal ion fine structure (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Explicit approximations that yield proton excitation cross sections and rate coefficients for fine-structure transitions in a wide variety of ions over the low and intermediate energy ranges are obtained in terms of the electric quadrupole transition probability and quadrupole radial integral of a given ion. The range of applicability of these approximations is discussed, and comparisons are made with available cross sections and rate coefficients. Values of quadrupole radial integrals are given for ground configurations of even-Z elements in higher stages of ionization. Proton excitation rate coefficients are computed for coronal transitions involving fine-structure levels in the ions Fe XIII, Fe XV, Fe XVIII, Fe XXI, and Ca XIII.
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 54; 1, Ja; Jan. 197
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  • 22
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    Viking S-band Doppler RMS phase fluctuations used to calibrate the mean 1976 equatorial corona (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Viking S-band Doppler RMS phase fluctuations (noise) and comparisons of Viking Doppler noise to Viking differenced S-X range measurements are used to construct a mean equatorial electron density model for 1976. Using Pioneer Doppler noise results (at high heliographic latitudes, also from 1976), an equivalent nonequatorial electron density model is approximated.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 152-166
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  • 23
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    Solar flare activity - Evidence for large-scale changes in the past (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: An analysis of radar and photographic meteor data and of spacecraft meteoroid-penetration data indicates that there probably has not been a large increase in meteoroid impact rates in the last 10,000 yr. The solar-flare tracks observed in the glass linings of meteoroid impact pits on lunar rock 15205 are therefore reanalyzed assuming a meteoroid flux that is constant in time. Based on this assumption, the data suggest that the production rate of Fe-group solar-flare tracks may have varied by as much as a factor of 50 on a time scale of about 10,000 yr. No independently obtained data are known to require conflict with this interpretation. Confidence in this conclusion is somewhat qualified by the experimental and analytical uncertainties involved, but the conclusion nevertheless remains the present 'best' explanation for the observed data trends.
    Keywords: SOLAR PHYSICS
    Type: Icarus; 32; Sept
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  • 24
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    An unusual aspect of solar wind speed variations during solar cycle 20 (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Geomagnetic records from 1868 through 1975 indicate that geomagnetic activity during 1973-1975 was unusually enhanced for that phase of the sunspot cycle (5-7 years after solar maximum). Previous work indicates that long-term variations in geomagnetic activity are closely coupled to long-term variations in the bulk flow speed of the solar wind. Thus, it is inferred that reported averages of the solar-wind speed for the 1973-1975 era are unusually large for that phase of the sunspot cycle.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; Aug. 1
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  • 25
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    A reexamination of two-fluid solar wind models (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The two-fluid solar-wind equations have been solved by a method which is approximately 50 times faster than any previously developed, through the use of asymptotic expansions which are self-consistently iterated upon to find a solution that passes through the critical point. The energy assumptions in two-fluid solar-wind models are reexamined, and the conclusions are as follows: (1) proton thermal conduction may not be neglected, (2) the Coulomb logarithm must be calculated as a function of radius, and (3) the electron and proton temperatures at the base need not be equal, even when the time scale for energy exchange between the species is an order of magnitude smaller than the expansion time at the base. It is possible to reproduce reasonable quiet-time solar-wind parameters at 1 AU, but only if the proton temperature is approximately twice the electron temperature at 1 solar radius. This may indicate that extended proton heating is important in the outer solar corona. Winds with velocities at 1 AU of 450 km/s are generated without nonthermal energy deposition but require high proton temperatures as well as very low densities at the base. Higher-velocity solutions are not possible in a spherically symmetric geometry for reasonable particle fluxes at 1 AU, and it is suggested that these higher-velocity states probably require additional heating, acceleration mechanisms, or nonradial flow.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; Aug. 1
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  • 26
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    Radio observations of interplanetary magnetic field structures out of the ecliptic (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Observations of the out-of-ecliptic trajectories of type III solar radio bursts have been obtained from simultaneous direction-finding measurements in two independent satellite experiments, IMP-6 with spin plane in the ecliptic and RAE-2 with spin plane normal to the ecliptic. Burst-exciter trajectories were observed which originated at the active region and then crossed the ecliptic plane at about 0.8 AU. A considerable large-scale north-south component of the interplanetary magnetic field followed by the exciters is found. The apparent north-south and east-west angular source sizes observed by the two spacecraft are approximately equal, and range from 25 deg at 600 kHz to 110 deg at 80 kHz.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 52; May 1977
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  • 27
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    A possible edge effect in enhanced network (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: K-line observations of enhanced network taken with the NASA/SPO Multichannel Spectrometer on September 28, 1975, in support of OSO-8 are discussed. The data show a correlation between core brightness and asymmetry for spatial scans which cross enhanced network boundaries. The implications of this result concerning mass flow in and near supergranule boundaries are discussed.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 52; May 1977
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  • 28
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    Streamtube analysis of a hydrogen-burning scramjet exhaust and simulation technique (1977)
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    Publication Date: 2011-08-17
    Description: A scramjet/airframe integration program and a technique for simulating thermally perfect scramjet exhaust flows (freon/argon gas blends) is studied to extend the technique to more complicated flows approaching the actual exhaust flow in complexity. The state of the flow and the accuracy of the substitute gas simulation are analyzed in the case of a shock discontinuity present. Findings are: scramjet exhaust flow is essentially frozen throughout the expansion at Mach 6 and Mach 8; flow behind moderate shocks remains frozen; the technique can accurately track static distributions in scramjet exhaust flows (shocked or unshocked).
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Journal of Aircraft; 14; Sept
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  • 29
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    Atmospheric turbulence and the apparent instantaneous diameter of the sun (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Astrometric data are perturbed by turbulent density fluctuations in the atmosphere over the frequency range from 0.0001 to 10 Hz by amounts that would limit the accuracy of solar-diameter measures significantly. Power spectra of the perturbations are compared with meteorological data to argue that thermal turbulence is dominant above 0.001 Hz and that mechanical turbulence (weather) is important below that frequency. Noise power in astrometry should be comparable under night or day conditions, but site location may be important for the strength of slowly passing waves.
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 59; 2, Ju; July 197
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  • 30
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    Multispacecraft observations of microscale fluctuations in the solar wind (1977)
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    Publication Date: 2011-08-17
    Description: Data from the Explorer 33 and 35 satellites were used to study Alfvenic fluctuations (i.e., fluctuations with a high correlation between perturbation in velocity and magnetic field) in the solar wind. It was found that the average minimum variance method does not give a good estimate of the phase front direction of these fluctuations. There is a distinct class of Alfvenic fluctuations with phase planes nearly parallel to the mean field B sub 0. The characteristic length of the phase fronts of the fluctuations is probably significantly greater than 50 R-E. It is concluded that since tangential discontinuities and possibly other types of static structures appear in Alfvenic fluctuations, these fluctuations are not solely Alfven waves.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; July 1
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  • 31
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    Preferred solar wind emitting longitudes on the sun (1977)
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    Publication Date: 2011-08-17
    Description: During the 11 1/2-year period from July 1964 through December 1975, high- and low-speed solar wind flows originated from preferred solar longitudes. The preferred longitude effect was most pronounced from 1970 onward but was also evident in the years preceding 1970. The most pronounced modulation in average solar wind speed with longitude (approximately 20%) was obtained when it was assumed that the synodic rotation period of the sun is 27.025 days. Some deep internal structure in the sun must ultimately be responsible for these long-lived longitudinal effects, which appear to rotate rigidly with the sun.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; June 1
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  • 32
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    A solar plasma stream measured by DRVID and dual-frequency range and Doppler radio metric data (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: S- and X-band DRVID, S- and X-band dual-frequency range (SX(p)), and Doppler (SX(p)) measured a 15-fold increase in the line-of-sight electron content of the solar plasma above the normal plasma background. A general increase in the plasma electron content continued for nearly 50 hours: it started about 12:00 (GMT) on 12 March 1976 and continued to grow until 17:00 (GMT) on 14 March. For the next 55 hours, between 17:00 (GMT) on 14 March to 00:54 (GMT) on 17 March, the plasma level diminished as the background level was approached. Not only were the temporal changes and absolute level of the plasma content measured but the measurements were also used to ascertain the mean-plasma-concentration location: it was estimated to be 4.1 light minutes from earth.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 43-54
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  • 33
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    Solar polar coronal hole - A mathematical simulation (1977)
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    Publication Date: 2011-08-17
    Description: The northern polar region of the sun was studied during July 1973 by Munro and Jackson through use of the white-light coronagraph and the X-ray photographs produced by the Skylab mission. They described the northern polar hole as nearly axisymmetric and gave the geometry and density distribution under this approximation. The present work gives quasi-radial approximation to the full magnetohydrodynamic equations for axisymmetric, polytropic solar wind flow to simulate this polar hole, with the benefit that model temperature and magnetic field intensities and distributions in this particular polar hole can be deduced. It is concluded that from 2 out to 5 solar radii the temperature varies only slightly with radius, but is larger near the center of the polar hole than at the edge. It is also found that the magnetic field intensity at 2 solar radii could be about 1 gauss at the center of the hole, decreasing toward the edge of the hole. If this is extrapolated to the surface, a field as high as 20 gauss is suggested.
    Keywords: SOLAR PHYSICS
    Type: Astrophysical Journal; vol. 217
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    Evidence for a structure-free state at high solar wind speeds (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The variability of the basic solar wind flow parameters in highand low-speed flows is submitted to a statistical analysis. Particular attention is given to the uniformity of solar wind high-speed flow conditions by comparing them with those of the low-speed so-called quiet solar wind. With the exception of the solar wind bulk velocity, the average fractional variation of each of a selected sample of basic solar wind parameters is found to be substantially larger during low-speed flow conditions than during high-speed flow conditions at 1 AU. As a statistical ensemble of events, the only thing steady and uniform about low-speed conditions is the bulk velocity. In all other respects, high-speed flows form a much more uniform ensemble of solar wind conditions than do the low-speed flows. It is concluded that the use of average high-speed flow parameters for comparison with steady-state spherically symmetric models of the coronal expansion is meaningful.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; Apr. 1
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  • 35
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    Viking Doppler noise used to determine the radial dependence of electron density in the extended corona (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The common form for radial dependence of electron density in the extended corona is given. By assuming proportionality between Doppler noise and integrated signal path electron density, Viking Doppler noise can be used to solve for a numerical value of X.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 167-171
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  • 36
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    Solar plasma: Viking 1975 interplanetary spacecraft dual-frequency Doppler data (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Viking 1975 interplanetary S- and X-band Doppler data are surveyed. These data show consistency with differenced range versus integrated Doppler (DRVID) data when there is solar plasma and with Faraday rotation data otherwise. An increase of solar plasma effects with decreasing sun-earth-probe (SEP) angle (approaching Mars orbit insertion) is demonstrated. The 2-way/3-way data indicate a homogeneous solar plasma structure over a 8,000-km spread. Occasional cycle slips in the data are pinpointed and tabulated.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 204-223
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  • 37
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    Precision insolation measurement under field conditions (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Work at the Jet Propulsion Laboratory had resulted in the development of a primary absolute cavity radiometer (PACRAD), which was recently accepted as an international standard of irradiance. The development of an wall-weather, field-worthy solar radiometer based on the PACRAD is discussed, and its calibration stability over a two-year period in the field is described.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 169-175
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  • 38
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    The solar spectrum in the vicinity of the Si IV lines at 1122 and 1128 A (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 61; 2, Oc; Oct. 197
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  • 39
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    On coronal Fe abundances and temperatures from XUV emission lines (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Data obtained by the OSO-7 spectroheliograph on strong XUV lines of five different Fe ions from the outer equatorial corona are presented. Interpretation of the data with a spherically symmetric model atmosphere gives average ion abundances for lines of sight at 0.3 solar radii from the limb. Fe XVI is usually more abundant than Fe XV, XIV, XII and IX, but there are times when Fe XII is more abundant than the other ions. The deviation of measured relative abundances of Fe XII, XIV, and XVI from predictions of ionization equilibrium at one temperature seems to indicate that there are appreciable temperature variations along lines of sight. Element abundances are very uncertain since they appear to depend so heavily on likely but unknown density irregularities along lines of sight.
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 53; Aug. 197
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  • 40
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    An empirical model for the solar wind velocity (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: An analytic expression for the average radial component of the Solar Wind velocity between 1 solar radius and 1 AU is developed. The model is constructed by assuming the conservation of particle flow in the Solar Wind and application of a twelve-year average measured value of the Solar Wind radial velocity at 1 AU.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 130-134
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  • 41
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    A first-principles derivation of Doppler noise expected from solar wind density fluctuations (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The level of Doppler noise (DN) expected from solar wind (SW) density fluctuations (DF) is derived beginning with the expression for refractive index variations. The calculation takes account of up and downlink paths and of the method actually used to produce the DN values. The usual assumptions that the DF are frozen in, that the large-scale radial variation can be separated from the DF, that the DF power spectrum is a power law with outer scale k sub 0 and that the DF are homogeneous on scales less than 2c delta t, delta t = sample time, are made. The result agrees quite well with previous observations of DN. Corrections for the finite number of points used in the actual algorithm are discussed.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 42-53
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  • 42
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    A preliminary analysis of Viking S-X Doppler data and comparison to results of Mariner 6, 7, and 9 DRVID measurements of the solar wind turbulence (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: S-X Doppler data obtained during more than 135 Viking passes from Aug. 3 to Dec. 15, 1976 were analyzed and compared with data from previous investigations using Mariner differenced range versus integrated Doppler to determine changes in the turbulence over the sunspot cycle. A comparison of the data indicates that: (1) electron density fluctuations decline with heliocentric distance; (2) the level of turbulence may be a factor of two lower near sunspot minimum than at maximum; and (3) the spectrum of the fluctuations may be steeper near sunspot minimum. The expected range error for various time scales and geometries is derived from the results.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network, Vol. 39; p 23-29
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  • 43
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    Electron densities in solar flares from line ratios of Ca XVII (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Keywords: SOLAR PHYSICS
    Type: Astronomy and Astrophysics; 60; 2, Se; Sept
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  • 44
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    Measuring solar wind velocity with spacecraft phase scintillations (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The measurement of spacecraft phase scintillations with a coherent dual-frequency radio system permits solar-wind velocity measurements based on multiple-station phase scintillations. Advantages of measuring solar-wind velocity on the basis of multiple-station phase scintillations are discussed with respect to amplitude scintillations. These advantages include the ability to carry out observations closer to the sun, a much wider range of possible baselines, a lower S/N ratio for long-baseline phase measurements, and a wider range of antenna sizes and receiver noise temperatures. NASA antennas particularly suitable for these measurements are identified, and observations with the coherent S/X radio system aboard various NASA spacecraft intended for deep-space missions are proposed.
    Keywords: SOLAR PHYSICS
    Type: Nature; 266; Apr. 7
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  • 45
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    Planetary tides during the Maunder Sunspot Minimum (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: In order to test the tidal theory of sunspots, sun-centered planetary conjunctions and tidal potentials are reconstructed for the period of the Maunder Minimum (1645 to 1715). These are found to be effectively indistinguishable from patterns of conjunctions and power spectra of tidal potential in the modern era of a well-established 11-yr sunspot cycle. The pattern of planetary tidal forces during the Maunder Minimum is then reconstructed to investigate the possibility that multiple-planet forces were somehow fortuituously cancelled at that time; i.e., the positions of the slower moving planets in the late 17th and early 18th centuries were such that conjunctions and tidal potentials were reduced in number and force. Calculations of daily positions for Mercury, Venus, earth, and Jupiter as well as daily values of the tidal potential for the period from 1450 to 2000 indicate no striking dissimilarities between the time of the Maunder Minimum and any other period considered.
    Keywords: SOLAR PHYSICS
    Type: Nature; 266; Mar. 31
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  • 46
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    Interplanetary baseline observations of type III solar radio bursts (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Simultaneous observations of type III radio bursts from spacecraft separated by 0.43 AU have been made using the solar orbiters Helios-A and Helios-B. The burst beginning at 19:22 UT on March 28, 1976, has been located from the intersection of the source directions measured at each spacecraft and from burst arrival-time differences. The source positions range from 0.03 AU from the sun at 3000 kHz to 0.08 AU at 585 kHz. The electron density along the burst trajectory and the exciter velocity (0.13c) were determined directly without the need to assume a density model, as has been done with single-spacecraft observations. The separation of Helios-A and -B has also provided measurements of burst directivity at low frequencies. For the March 28 burst the intensity observed from near the source longitude (Helios-B) was 3-10dB greater than that from 60 deg west of the source (Helios-A)
    Keywords: SOLAR PHYSICS
    Type: Solar Physics; 54; Oct. 197
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  • 47
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    Solar-generated quasi-biennial geomagnetic variation (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The existence of highly correlated quasi-biennial variations in the geomagnetic field and in solar activity is demonstrated. The analysis uses a numerical filter technique applied to monthly averages of the geomagnetic horizontal component and of the Zurich relative sunspot number. Striking correlations are found between the quasi-biennial geomagnetic variations determined from several magnetic observatories located at widely different longitudes, indicating the worldwide nature of the obtained variation. The correlation coefficient between the filtered Dst index and the filtered relative sunspot number is found to be -0.79 at confidence level greater than 99% with a time lag of 4 months, solar activity preceding the Dst variation. The correlation between the unfiltered data of Dst and those of the sunspot number is also high with a similar time lag. Such a time lag has not been discussed in the literature, and a further study is required to establish the mode of sun-earth relationship that gives this time delay.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; Dec. 1
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  • 48
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    On the alignment of plasma anisotropies and the magnetic field direction in the solar wind (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: One year's Imp 6 solar wind plasma and magnetic field data are examined to determine whether anisotropies in particle velocity distributions are aligned with the measured interplanetary magnetic field vector. Alignment of components in the analysis plane was generally found to be excellent whenever plasma parameter magnitudes were larger than determination uncertainties, although some spread exists (typical rms approximately equal to 10 deg). By assuming cylindrical symmetry about the simultaneously measured magnetic field vector during the 1-year interval under study, three-dimensional values of selected solar wind plasma thermal parameters were constructed from the two-dimensional plasma measurements, and the statistical properties of their distributions have been tabulated.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysical Research; 82; Dec. 1
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  • 49
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    How good is jet lift VTOL technology (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The status of technologies for jet-lift V/STOL aircraft is examined, and a critical review of the performance of jet-lift VTOL aircraft built to date is made. Most jet-lift aircraft have suffered from adverse propulsion-induced effects during takeoff and landing. Flight dynamics of jet-lift aircraft have suffered from shortcomings in static and dynamic stability, control characteristics, and flight path control. Some of the main problems to be considered during the selection of a propulsion system arrangement for a V/STOL fighter are discussed. At present, experimental and analytical data on supersonic V/STOL configurations are insufficient to permit evaluating propulsion system arrangements.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Astronautics and Aeronautics; 15; Dec. 197
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  • 50
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    Solar oscillations (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The main observational results and related theoretical investigations concerning solar oscillations are reviewed. The normal modes of oscillation of the sun are classified according to their angular eigenvalues and the number of their radial nodes. Observations of excited normal modes are discussed, particularly in relation to five-minute oscillations, nonlinearly coupled unstable g-modes, oscillations of the sun's apparent diameter, and reported oscillations of the solar surface with a period of 2 hr 40 min. Linear stability calculations are briefly examined, and stochastic excitation of p-modes by turbulent convection is considered. The five-minute oscillations are described as the superposition of many excited nonradial p-modes.
    Keywords: SOLAR PHYSICS
    Type: Comments on Modern Physics; vol. 7
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  • 51
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    Investigation of coronal holes in the radio and far-ultraviolet ranges (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Results of coronal-hole observations carried out in the far-UV with a spectro-heliometer aboard Skylab are compared with corresponding results of ground-based radioheliograph measurements performed at frequencies of 80 and 160 MHz. It is found that the electron density derived from the far-UV observations for the transition region and lower corona is nearly three times greater than the value computed on the basis of the radio data. Unsuccessful attempts are made to eliminate this discrepancy by recalibrating the radio data and by recalculating the ionization equilibrium. A substantial local enhancement of the heavy-element abundance in certain parts of the transition region and inner chromosphere is considered as a possible cause of the discrepancy.
    Keywords: SOLAR PHYSICS
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  • 52
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    Helios-1 Faraday rotation experiment - Results and interpretations of the solar occultations in 1975 (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: The first of two solar occultations of the satellite Helios-1 in 1975 occurred in April when the satellite's ray path approached the west limb of the sun to a minimum distance of 1.63 solar radii. The second occultation took place in late August/early September when Helios-1 was totally eclipsed by the photosphere. Measurements of the polarization angle of the linearly polarized telemetry signal were performed with automatic tracking polarimeters at the 64 m Goldstone Tracking Station in California and also at the 100 m radio telescope in Effelsberg, West Germany. The coronal Faraday rotation as a function of the solar offset for both occultations is shown in graphs. The theoretical significance of the observations is investigated.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysics - Zeitschrift fuer Geophysik; 42; 6, 19; 1977
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  • 53
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    Time delay occultation data of the Helios spacecrafts and preliminary analysis for probing the solar corona (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: S-band time delay measurements were collected from the spacecrafts Helios A and B during three solar occultations in 1975/76 within heliocentric distances of about 3 and 215 solar radii in terms of range, Doppler frequency shift, and electron content. A description is given concerning some characteristic features of the methods of measurement and data processing. Typical data sets are discussed to probe the electron density distribution near the sun (west and east limb as well) including the outer and extended corona. Steady-state and dynamical aspects of the solar corona are presented and compared with earth-bound K-coronagraph measurements. Using a weighted least squares estimation 3 parameters of an average coronal electron density profile are derived in a preliminary analysis to yield electron densities of about 130 billion; 100 million; 7 million/cu m at r?3; 65; 215 solar radii. Transient phenomena are discussed and a velocity of propagation v approximately 900 km/s for plasma ejecta from a solar flare is determined from an extraordinary set of Helios B electron content measurements on April 30/May 1, 1976.
    Keywords: SOLAR PHYSICS
    Type: Journal of Geophysics - Zeitschrift fuer Geophysik; 42; 6, 19; 1977
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  • 54
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    RMS electron density fluctuation at 1 AU (1977)
    In:  Other Sources
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    Publication Date: 2011-08-17
    Description: Analytic expressions at 1 AU for the average RMS Electron Density Fluctuation and the ratio of RMS Electron Density Fluctuation to Electron Density, both as functions of the observational time scale, are constructed from average spacecraft in situ density measurements at approximately 1 AU and columnar phase fluctuation measurements over a wide variety of signal closet approach points. Additionally, the (one-dimensional) Electron Density Fluctuation spectrum and the Doppler phase fluctuation scale are derived, and various extrapolations to the region interior to 1 AU are made.
    Keywords: SOLAR PHYSICS
    Type: The Deep Space Network; p 135-140
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  • 55
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    Effect of endwall cooling on secondary flows in turbine stator vanes (1977)
    In:  CASI
    Details
    Publication Date: 2012-05-19
    Description: An experimental investigation was performed to determine the effect of endwall cooling on the secondary flow behavior and the aerodynamic performance of a coreturbine stator vane. The investigation was conducted in a cold-air, full-annular cascade, where three-dimensional effects could be obtained. Two endwall cooling configurations were tested. In the first configuration, the cooling holes were oriented so that the coolant was injected in line with the inviscid streamline direction. In the second configuration, the coolant was injected at an angle of 15 deg to the inviscid streamline direction and oriented toward the vane pressure surface. In both cases the stator vanes were solid and uncooled so that the effect of endwall cooling could be obtained directly. Total-pressure surveys were taken downstream of the stator vanes over a range of cooling flows at the design, mean-radius, critical velocity ratio of 0.778. Changes in the total-pressure contours downstream of the vanes were used to obtain the effect of endwall cooling on the secondary flows in the stator. Comparisons were made between the two cooled-endwall configurations and with the results obtained previously for solid endwalls.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: AGARD Secondary Flows in Turbomachines; 29 p
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  • 56
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    Advanced low-NO(x) combustors for supersonic high-altitude gas turbines (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The impact of gas-turbine-engine-powered aircraft on worldwide pollution was defined within two major areas of contribution. First, the contribution of aircraft to the local air pollution of metropolitan areas and, second, the long-term effects on the chemical balance of the stratosphere of pollutants emitted from future generations of high-altitude, supersonic commercial and military aircraft. Preliminary findings indicate that stratospheric oxides of nitrogen (NOx) emissions may have to be limited to very low levels if, for example, ozone depletion with concomitant increases in sea-level radiation, are to be avoided. Theoretical considerations suggest that (NOx) levels as low as 1.0 gram per kilogram of fuel and less should be attainable from a idealized premixed type of combustor. Experimental rig studies were intended to explore new combustor concepts designed to minimize the formation of (NOx) in aircraft gas turbines and to define their major operational problems and limitations.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 393-415
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  • 57
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    Soot formation in a turbulent swirling flow (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The qualitative understanding of soot formation in simple models of gas turbine primary-zone combustors is summarized. Soot formation in flame radiation and air pollution was investigated. Results are presented, namely: (1) if the fuel is premixed with air in approximately stoichiometric proportions, the sequence of states that a fluid element undergoes as it burns is quite different from the sequence when liquid or vapor fuel is injected into an air-flow; (2) swirling flows, as are typical or swirl-can combustors, when burning, can amplify small aerodynamic disturbances upstream of the swirl vanes; and (3) different fuels form significantly different amounts of soot. Each of these effects makes major changes in the amount of soot formed in a given combustor.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 309-321
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  • 58
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    Pollution reduction technology program for turboprop engines (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The reduction of CO, HC, and smoke emissions while maintaining acceptable NO(x) emissions without affecting fuel consumption, durability, maintainability, and safety was accomplished. Component combustor concept screening directed toward the demonstration of advanced combustor technology required to meet the EPA exhaust emissions standards for class P2 turboprop engines was covered. The combustion system for the Allison 501-D22A engine was used, and three combustor design concepts - reverse flow, prechamber, and staged fuel were evaluated.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 125-147
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  • 59
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    Ceramic composite protection for turbine disc bursts (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Ceramic composite turbine disc protection panels for the A300B were developed using armor technology. Analytical predictions for modifying the ballistic projectile armor system were verified by a test program conducted to qualify the rotor containment system. With only a slight change in the areal density of the armor system a more than two-fold increase in kinetic energy protection level was achieved. Thickness of the fiberglass reinforced plastic backing material was increased to achieve an optimum ratio of ceramic thickness to backing thickness for the different ballistic defeat condition.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 277-293
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  • 60
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    Materials and manufacturing processes for increased life/reliability (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Improvements in both quality and durability of disk raw material for both military and commercial engines necessitated an entirely new concept in raw material process control which imposes careful selection, screening and sampling of the basic alloy ingredients, followed by careful monitoring of the melting parameters in all phases of the vacuum melting sequence. Special care is taken to preclude solidification conditions that produce adverse levels of segregation. Melt furnaces are routinely cleaned and inspected for contamination. Ingots are also cleaned and inspected before entering the final melt step.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 347-368
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  • 61
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    Numerical analysis of projectile impact in woven texile structures (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Computer codes were developed for simulating the dynamic fracture and viscoelastic constitutive response due to stress wave interaction and reflections caused by ballistic impact on woven textiles. The method, which was developed for use in the design and analysis of protection devices for personnel armor, has potential for use in studies of rotor blade burst containment at high velocity. Alterations in coding required for burst containment problems are discussed.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Assessment of Technol. for Turbojet Engine Rotor Failures; p 247-260
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  • 62
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    Lightweight engine containment (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Kevlar fabric styles and weaves were studied, as well as methods of application for advanced gas turbine engines. The Kevlar material was subjected to high speed impacts by simple projectiles fired from a rifle, as well as more complex shapes such as fan blades released from gas turbine rotors in a spin pit. Just contained data was developed for a variety of weave and/or application techniques, and a comparative containment weight efficiency was established for Kevlar containment applications. The data generated during these tests is being incorporated into an analytical design system so that blade containment trade-off studies between Kevlar and metal case engine structures can be made. Laboratory tests and engine environment tests were performed to determine the survivability of Kevlar in a gas turbine environment.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 235-245
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  • 63
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    Approaches to rotor fragment protection (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Key airworthiness design criteria considerations for fragment protection as found in various FAA requirements in FAR Parts 25 and 33, and in interpretive 8110 orders are reviewed. The impact of providing aircraft armor in lieu of engine armor for typical three- and four-engine wide bodied transports for protection within the length of the engine case as well as from fragments exiting ahead of the enlet engine inlet flange is assessed. For protection within the length of the engine case, armor weight penalties, plus fuel burned and dollar cost of carrying the armor protection are defined. Immediately ahead of the inlet flange, direct tangential impacts are predominant, but further forward, rebound impacts predominate. Armor thickness requirements and fuel cost impact of protection are given.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 101-103
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    Engine Non-Containment: The UK CAA View (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Airworthiness accidents account for roughly one quarter of the total number of accidents to public transport turbojet aircraft. The most reliable, practicable, and cost-effective means of minimizing damage outside the confines of the nacelle is to make the aircraft design invulnerable to any debris which may affect the aircraft. A failure model was developed for use by aircraft builders in measuring the freedom from catastrophe factor of their design.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 11-32
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  • 65
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    Effect of ambient temperature and humidity on emissions of an idling gas turbine (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The effects of inlet pressure, temperature, and humidity on the oxides of nitrogen produced by an engine operating at takeoff power setting were investigated and numerous correction factors were formulated. The effect of ambient relative humidity on gas turbine idle emissions was ascertained. Experimentally, a nonvitiating combustor rig was employed to simulate changing combustor inlet conditions as generated by changing ambient conditions. Emissions measurements were made at the combustor exit. For carbon monoxide, a reaction kinetic scheme was applied within each zone of the combustor where initial species concentrations reflected not only local combustor characteristics but also changing ambient conditions.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 437-456
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  • 66
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    Global atmospheric sampling program (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Automated instruments were installed on a commercial B-747 aircraft, during the program, to obtain baseline data and to monitor key atmospheric constituents associated with emissions of aircraft engines in order to determine if aircraft are contributing to pollution of the upper atmosphere. Data thus acquired on a global basis over the commercial air routes for 5 to 10 years will be analyzed. Ozone measurements in the 29,000 to 45,000 foot altitude were expanded over what has been available from ozonesondes. Limited aerosol composition measurements from filter samples show low levels of sulfates and nitrates in the upper troposphere. Recently installed instruments for measurement of carbon monoxide and condensation nuclei are beginning to return data.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 323-355
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  • 67
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    Emissions control for ground power gas turbines (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The similarities and differences of emissions reduction technology for aircraft and ground power gas turbines is described. The capability of this technology to reduce ground power emissions to meet existing and proposed emissions standards is presented and discussed. Those areas where the developing aircraft gas turbine technology may have direct application to ground power and those areas where the needed technology may be unique to the ground power mission are pointed out. Emissions reduction technology varying from simple combustor modifications to the use of advanced combustor concepts, such as catalysis, is described and discussed.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 203-242
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  • 68
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    Pollution reduction technology program for small jet aircraft engines: Class T1 (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Small jet aircraft engines (EPA class T1, turbojet and turbofan engines of less than 35.6 kN thrust) were evaluated with the objective of attaining emissions reduction consistent with performance constraints. Configurations employing the technological advances were screened and developed through full scale rig testing. The most promising approaches in full-scale engine testing were evaluated.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 149-180
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  • 69
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    Emissions Reduction Technology Program (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Combustor concepts having the potential for significantly lower emissions levels were investigated. The combustor emissions reduction was measured in an engine test. Emission characteristics common to all engine classes are shown. Multiple-burning zone combustors, specifically the double-annular and swirl-can combustors were studied. Airblast and air-assist fuel injection techniques were evaluated for emissions control potential. The combustor sceening and refining phases are summarized.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 19-58
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  • 70
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    Turbine disks for improved reliability (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Advanced disk structural concepts were employed to improve the cyclic lives and reliability of turbine disks. Analytical studies were conducted to evaluate bore-entry disks as potential replacements for the existing first-stage turbine disks in the CF6-50 and JT8D-17 engines. Results of low cycle fatigue, burst, fracture mechanics, and fragment energy analyses are summarized for the advanced disk designs and the existing disk designs, with both conventional and advanced disk materials. Other disk concepts such as composite, laminated, link, multibore, multidisk, and spline disks were also evaluated for the CF6-50 engine.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 389-411
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  • 71
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    Analysis methods for Kevlar shield response to rotor fragments (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Several empirical and analytical approaches to rotor burst shield sizing are compared and principal differences in metal and fabric dynamic behavior are discussed. The application of transient structural response computer programs to predict Kevlar containment limits is described. For preliminary shield sizing, present analytical methods are useful if insufficient test data for empirical modeling are available. To provide other information useful for engineering design, analytical methods require further developments in material characterization, failure criteria, loads definition, and post-impact fragment trajectory prediction.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 261-275
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  • 72
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    Rotor burst protection criteria and implications (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Current aircraft design practices to minimize the hazard from rotor bursts are described. The consequences of non-contained engine failures and the impact of rotor burst protection systems on aircraft design are discussed.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 37-43
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  • 73
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    Solar physics (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Solar monitors on space platforms are discussed. Several experiments, utilizing different techniques for solar constants, spectral irradiance, and cross calibration carried out either on a space platform or a nearby satellite are included. The correlation monitors permit effective manned interface with the major solar instruments and with magnetospheric/atmospheric experiments requiring specific solar conditions before initiation.
    Keywords: SOLAR PHYSICS
    Type: NASA Workshop on Solar-Terrest. Studies from a Manned Space Station 10p (SEE N77-32549 23-42)
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  • 74
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    Laboratory studies of lean combustion (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The fundamental processes controlling lean combustion were observed for better understanding, with particular emphasis on the formation and measurement of gas-phase pollutants, the stability of the combustion process (blowout limits), methods of improving stability, and the application of probe and optical diagnostics for flow field characterization, temperature mapping, and composition measurements. The following areas of investigation are described in detail: (1) axisymmetric, opposed-reacting-jet-stabilized combustor studies; (2) stabilization through heat recirculation; (3) two dimensional combustor studies; and (4) spectroscopic methods. A departure from conventional combustor design to a premixed/prevaporized, lean combustion configuration is attractive for the control of oxides of nitrogen and smoke emissions, the promotion of uniform turbine inlet temperatures, and, possibly, the reduction of carbon monoxide and hydrocarbons at idle.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 417-436
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  • 75
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    Alternative fuels (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Potential problems related to the use of alternative aviation turbine fuels are discussed and both ongoing and required research into these fuels is described. This discussion is limited to aviation turbine fuels composed of liquid hydrocarbons. The advantages and disadvantages of the various solutions to the problems are summarized. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source. The second solution is to minimize energy consumption at the refinery and keep fuel costs down by relaxing specifications.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 277-308
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  • 76
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    Summary of emissions reduction technology programs (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The NASA emissions reduction contract programs for EPA aircraft engine classes P2 (turboshaft engines), T1 (jet engines with thrust under 8000 lb), T4 (JT8D) engines), and T2 (jet engines with thrust over 8000 lb) are discussed. The most important aspects of these programs, the commonality of approaches used, the test results, and assessments regarding applications of the derived technology are summarized.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 181-202
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  • 77
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    NASA/Pratt and Whitney experimental clean combustor program: Engine test results (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: A two-stage vorbix (vortex burning and mixing) combustor and associated fuel system components were successfully tested in an experimental JT9D engine at steady-state and transient operating conditions, using ASTM Jet-A fuel. Full-scale JT9D experimental engine tests were conducted in a phase three aircraft experimental clean combustor program. The low-pollution combustor, fuel system, and fuel control concepts were derived from phase one and phase two programs in which several combustor concepts were evaluated, refined, and optimized in a component test rig. Significant pollution reductions were achieved with the combustor which meets the performance, operating, and installation requirements of the engine.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 91-123
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  • 78
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    Stratospheric cruise emission reduction program (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: A recently implemented NASA effort specifically aimed at reducing cruise oxides of nitrogen from high-altitude aircraft is discussed. The desired emission levels and the combustor technology required to achieve them are discussed. A brief overview of the SCERP operating plan is given. Lean premixed-prevaporized combustion and some of the potential difficulties that are associated with applying this technique to gas turbine combustors are examined. Base technology was developed in several key areas. These fundamental studies are viewed as a requirement for successful implementation of the lean premixed combustion technique.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 357-391
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  • 79
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    General aviation piston-engine exhaust emission reduction (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: To support the promulgation of aircraft regulations, two airports were examined, Van Nuys and Tamiami. It was determined that the carbon monoxide (CO) emissions from piston-engine aircraft have a significant influence on the CO levels in the ambient air in and around airports, where workers and travelers would be exposed. Emissions standards were set up for control of emissions from aircraft piston engines manufactured after December 31, 1979. The standards selected were based on a technologically feasible and economically reasonable control of carbon monoxide. It was concluded that substantial CO reductions could be realized if the range of typical fuel-air ratios could be narrowed. Thus, improvements in fuel management were determined as reasonable controls.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 243-275
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  • 80
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    Pollution reduction technology program for class T4(JT8D) engines (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The technology required to develop commercial gas turbine engines with reduced exhaust emissions was demonstrated. Can-annular combustor systems for the JT8D engine family (EPA class T4) were investigated. The JT8D turbofan engine is an axial-flow, dual-spool, moderate-bypass-ratio design. It has a two-stage fan, a four-stage low-pressure compressor driven by a three-stage low-pressure turbine, and a seven-stage high-pressure compressor driven by a single-stage high-pressure turbine. A cross section of the JT8D-17 showing the mechanical configuration is given. Key specifications for this engine are listed.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: Aircraft Eng. Emissions; p 29-89
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  • 81
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    Blade fragment energy analysis (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Two classes of fan blade fragments were considered in an analysis of blade fragment energy. The first, of relatively small size (.15 pound) and energy, tends to rebound from the fan and case when liberated in an FOD encounter. These small fragments have relatively low secondary damage potential and are less demanding in terms of protection. The larger fan blade fragments are ejected in a more direct release trajectory with higher energy and hence can represent a higher potential hazard. Simplified analytical methods were used to describe blade fragment energy transfer kinematics, establish fragment energy levels, evaluate damage potential and configure protection. The approach, methodology, and application are discussed as a possible building block for other applications. Development of effective local protection using Kevlar is also discussed. Analysis methods developed and applied to the rebound fragment problem and to the large direct release fragment problem are described.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 93-95
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  • 82
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    Development of fiber shields for engine containment (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Tests were conducted in translational launchers and spin pits to generate empirical data used in the design of a Kevlar shield for containing engine burst debris. Methods are given for modeling the relationship of fragment characteristics to shielding requirements. The change in relative importance of shield mounting provisions as fragment energy is increased is discussed.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 217-234
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  • 83
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    Types of rotor failure and characteristics of fragments (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Noncontained rotor failures in U.K. engines resulting from low cycle fatigue, low cycle fatigue with superimposed high cycle fatigue, and overheating and-or overspeeding were analyzed. The size, shape, weight, velocity, energy, and direction of the fragments released from turbines and compressors were studied and are presented in graph.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 65-92
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  • 84
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    Designing the L-1011 to minimize rotor failures effects (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Design philosophies used in the L-1011 aircraft to provide protection against rotor fragments include: (1) incorporating into the rotor design features that tend to promote small fragments if failure occurs; (2) containing the fragments within the engine shell or greatly reducing the energy content of those fragments that are eventually uncontained; (3) shielding vulnerable elements or systems with heavy structural members that tend to stop or deflect high velocity fragments; and (4) incorporating redundant and/or backup systems into the basic design and separating these systems so as to minimize the probability that more than one system will be damaged by an uncontained rotor fragment. Some of the design features that were incorporated into the Rolls-Royce RB211 engine are discussed, and two in-service experiences are considered in order to illustrate the practical operation of these features.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 97-100
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  • 85
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    Status of the NASA/General Electric experimental clean combustor program, phase 3 (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: The technology required to design and develop advanced commercial, conventional-takeoff-and-landing aircraft engines with significantly lower pollutant exhaust emissions levels than those of current-technology engines was generated and demonstrated. The target pollutant emissions reductions in tests of an advanced commercial aircraft turbofan engine were attained by developing advanced combustor designs. This technology is intended to be applicable to advanced military aircraft engines. The primary focus was on reducing the levels of the gaseous pollutant emissions.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 37-58
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  • 86
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    Environmental protection agency aircraft emissions standards (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Emissions of air pollutants from aircraft were investigated in order to determine: (1) the extent to which such emissions affect air quality in air quality control regions throughout the United States; and (2) the technological feasibility of controlling such emissions. The basic information supporting the need for aircraft emissions standards is summarized. The EPA ambient air quality standards are presented. Only the primary (health related) standards are shown. Of the six pollutants, only the first three, carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides, are influenced significantly by aircraft.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA. Lewis Res. Center Aircraft Eng. Emissions; p 1-17
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  • 87
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    Some airline experience in preventing engine rotor failures (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Methods used by airlines, with the assistance of the engine manufacturers to achieve control over the type of problems which lead to uncontained failure and avoid many potential problems are discussed.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 413-418
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  • 88
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    Application of a flight-line disk crack detector to a small engine (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: A disk crack detector was developed and applied to a small military engine for use as a flight-line turbine crack monitor. The system consists of an eddy current type sensor and its cables within the engine, external connecting cables, and a remotely located electrical capacitance-conductance bridge and signal analyzer. As the turbine spins, the rotor is monitored by the sensor for radial surface cracks emanating from the interblade region of the rotor.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures 383-388 (SEE N78-10068 01-07)
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  • 89
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    NDE: A key to engine rotor life prediction (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: A key ingredient in the establishment of safe life times for critical components is the means of reliably detecting flaws which may potentially exist. Currently used nondestructive evaluation procedures are successful in detecting life limiting defects; however, the development of automated and computer aided NDE technology permits even greater assurance of flight safety.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 369-382
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  • 90
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    Design of rotors for improved structural life (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Major rotor design criteria are discussed with particular emphasis on those aspects of rotor design that ensure long life component integrity. Dynamic considerations, that necessitate tuning of bladed disk and seal assemblies to avoid excessive vibratory stress at both design and off-design conditions are reviewed as well as low cycle fatigue considerations, which have resulted in detailed analysis procedures to establish part temperature and stress variation throughout an operating cycle and extensive specimen and component fatigue testing to establish safe cyclic operating limits. The frequency, size, and behavior of intrinsic material defects were investigated. Manufacturing process improvements, including the application of increasingly sophisticated inspection techniques and quality control procedures are reviewed in light of their impact on component durability.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 331-346
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  • 91
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    Concepts for the development of light-weight composite structures for rotor burst containment (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Published results on rotor burst containment with single materials, and on body armor using composite materials were used to establish a set of hypotheses about what variables might control the design of a weight-efficient protective device. Based on modern concepts for the design and analysis of small optimum seeking experiments, a particular experiment for evaluating the hypotheses and materials was designed. The design and methods for the analysis of results are described. The consequence of such hypotheses is that the device should consist of as many as four concentric rings, each to consist of a material uniquely chosen for its position in the penetration sequence.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 295-330
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  • 92
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    Engine non-containment: UK risk assessment methods (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: More realistic guideline data must be developed for use in aircraft design in order to comply with recent changes in British civil airworthiness requirements. Unrealistically pessimistic results were obtained when the methodology developed during the Concorde SST certification program was extended to assess catastrophic risks resulting from uncontained engine rotors.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 45-63
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  • 93
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    Federal Aviation Administration's approach to engine rotor integrity (1977)
    In:  CASI
    Details
    Publication Date: 2016-06-07
    Description: Sections of the U.S. Airworthiness Standards which contribute to rotor integrity are explored. Reports published under NASA's Rotor Burst Protection program are included in current FAA studies to determine the weight penalty for two different levels of increased containment, and the penalty associated with protecting critical structure and systems, the passenger cabin, and the flight deck by strategic location of armor shields or deflector plates. Findings of the two studies will be used to propose revisions to regulations to reduce uncontained rotor failures.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: MIT An Assessment of Technol. for Turbojet Engine Rotor Failures; p 1-9
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  • 94
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    Quiet Clean Short-haul Experimental Engine (QCSEE) under-the-wing engine composite fan blade design report (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: A total of 38 quiet clean short haul experimental engine under the wing composite fan blades were manufactured for various component tests, process and tooling, checkout, and use in the QCSEE UTW engine. The component tests included frequency characterization, strain distribution, bench fatigue, platform static load, whirligig high cycle fatigue, whirligig low cycle fatigue, whirligig strain distribution, and whirligig over-speed. All tests were successfully completed. All blades planned for use in the engine were subjected to and passed a whirligig proof spin test.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-135046 , R77AEG177
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  • 95
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    Quiet Clean Short-haul Experimental Engine (QCSEE) main reduction gears detailed design report (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: Lightweight turbine engines with geared slower speed fans are considered. The design of two similar but different gear ratio, minimum weight, epicyclic star configuration main reduction gears for the under the wing (UTW) and over the wing (OTW) engines is discussed. The UTW engine reduction gear has a ratio of 2.465:1 and a 100% power design rating of 9885 kW (13,256 hp) at 3143 rpm fan speed. The OTW engine reduction gear has a ratio of 2.062:1 and a 100% power design rating of 12813 kW (17183 hp) at 3861 rpm fan speed. Details of configuration, stresses, deflections, and lubrication are presented.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-134872 , CW-WR-77-024
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  • 96
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    Quiet Clean Short-haul Experimental Engine (QCSEE) main reduction gears test program (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: Sets of under the wing (UTW) engine reduction gears and sets of over the wing (OTW) engine reduction gears were fabricated for rig testing and subsequent installation in engines. The UTW engine reduction gears which have a ratio of 2.465:1 and a design rating of 9712 kW at 3157 rpm fan speed were operated at up to 105% speed at 60% torque and 100% speed at 125% torque. The OTW engine reduction gears which have a ratio of 2.062:1 and a design rating of 12,615 kW at 3861 rpm fan speed were operated at up to 95% speed at 50% torque and 80% speed at 109% torque. Satisfactory operation was demonstrated at powers up to 12,172 kW, mechanical efficiency up to 99.1% UTW, and a maximum gear pitch line velocity of 112 m/s (22,300 fpm) with a corresponding star gear spherical roller bearing DN of 850,00 OTW. Oil and star gear bearing temperatures, oil churning, heat rejection, and vibratory characteristics were acceptable for engine installation.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-134669 , CW-WR-77-008
    Format: application/pdf
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  • 97
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    Acoustic analysis of aft noise reduction techniques measured on a subsonic tip speed 50.8 cm (twenty inch) diameter fan (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: Sound data which were obtained during tests of a 50.8 cm diameter, subsonic tip speed, low pressure ratio fan were analyzed. The test matrix was divided into two major investigations: (1) source noise reduction techniques; and (2) aft duct noise reduction with acoustic treatment. Source noise reduction techniques were investigated which include minimizing second harmonic noise by varying vane/blade ratio, variation in spacing, and lowering the Mach number through the vane row to lower fan broadband noise. Treatment in the aft duct which includes flow noise effects, faceplate porosity, rotor OGV treatment, slant cell treatment, and splitter simulation with variable depth on the outer wall and constant thickness treatment on the inner wall was investigated. Variable boundary conditions such as variation in treatment panel thickness and orientation, and mixed porosity combined with variable thickness were examined. Significant results are reported.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-134891 , R75AEG368
    Format: application/pdf
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  • 98
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    Quiet Clean Short-haul Experimental Engine (QCSEE) Over The Wing (OTW) design report (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: The design, fabrication, and testing of two experimental high bypass geared turbofan engines and propulsion systems for short haul passenger aircraft are described. The propulsion technology required for future externally blown flap aircraft with engines located both under the wing and over the wing is demonstrated. Composite structures and digital engine controls are among the topics included.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-134848 , R75AEG443
    Format: application/pdf
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  • 99
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    Quiet Clean Short-haul Experimental Engine (QCSEE): The aerodynamic and mechanical design of the QCSEE under-the-wing fan (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: The design, fabrication, and testing of two experimental high bypass geared turbofan engines and propulsion systems for short haul passenger aircraft are described. The aerodynamic and mechanical design of a variable pitch 1.34 pressure ratio fan for the under the wing (UTW) engine are included. The UTW fan was designed to permit rotation of the 18 composite fan blades into the reverse thrust mode of operation through both flat pitch and stall pitch directions.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-135009 , R75AEG484
    Format: application/pdf
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  • 100
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    Quiet Clean Short-haul Experimental Engine (QCSEE) Under-The-Wing (UTW) composite nacelle subsystem test report (1977)
    In:  CASI
    Details
    Publication Date: 2019-06-27
    Description: The element and subcomponent testing conducted to verify the under the wing composite nacelle design is reported. This composite nacelle consists of an inlet, outer cowl doors, inner cowl doors, and a variable fan nozzle. The element tests provided the mechanical properties used in the nacelle design. The subcomponent tests verified that the critical panel and joint areas of the nacelle had adequate structural integrity.
    Keywords: AIRCRAFT PROPULSION AND POWER
    Type: NASA-CR-135075 , R76AEG420
    Format: application/pdf
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