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A Flight Investigation of the Stability of a Towed Body

Description: Report presenting flight tests to determine whether a towed body that was designed to meet certain specifications met the stability specification, which required that angular deviations in flight should be less than 1 degree. The requirement was met in flight in smooth air, but not in rough air, where the rolling motions were considerably larger.
Date: October 1942
Creator: Phillips, W. H.
Partner: UNT Libraries Government Documents Department

Stability of a Body Stabilized by Fins and Suspended From an Airplane

Description: Report discusses the results of an investigation into the oscillations performed by suspended bodies like trailing airspeed heads and other towed devices. The most violent types of instability observed were found to be caused by unsteady or nonuniform air flow where the cable was lowered from the airplane. No method was found for reducing cable oscillations in short cable lengths, but the degree of stability present was considered satisfactory as long as the suspended body is lowered into a uniform air stream.
Date: April 1944
Creator: Phillips, W. H.
Partner: UNT Libraries Government Documents Department

Principal Facts and a Discussion of Terrain Correction Methods for the Complete Bouguer Gravity Anomaly Map of the Cascade Mountains, Washington

Description: Since 1974, the Division of Geology and Earth Resources, in conjunction with the US Department of Energy, has supported gravity studies in the Cascade Mountains of Washington State. Results of the Cascade gravity project are summarized graphically as a complete Bouguer gravity anomaly map of the Cascade Mountains, Washington (Danes and Phillips, 1983). This report provides supplementary data and documentation for the complete Bouguer gravity anomaly map. Presented are principal gravity facts, simple Bouguer and Free-air gravity anomalies, computational methods, error analysis and a discussion of terrain corrections.
Date: February 1983
Creator: Danes, Z. F. & Phillips, W. M.
Partner: UNT Libraries Government Documents Department

Measurements of the Flying Qualities of a Hawker Hurricane Airplane

Description: Report presenting an investigation of the flying qualities of a Hawker Hurricane airplane. Thirteen flights and approximately 17 hours of flying time were required to complete the tests, which included extensive measurements of stability, controllability, and stalling characteristics. The results were similar to the flying qualities of other previously studied pursuit airplanes.
Date: April 1942
Creator: Nissen, J. M. & Phillips, W. H.
Partner: UNT Libraries Government Documents Department

Flight Tests of Various Tail Modifications on the Brewster XSBA-1 Airplane 1: Measurements of Flying Qualities With Original Tail Surfaces

Description: Report presenting a series of tests of the Brewster XSBA-1 airplane conducted to determine the effect of various tail modifications. The current report describes an investigation of flying qualities of the airplanes with its original tail surfaces. Testing regarding longitudinal stability and control and stalling characteristics are provided.
Date: June 1943
Creator: Phillips, W. H. & Nissen, J. M.
Partner: UNT Libraries Government Documents Department

Stalling Characteristics of the Supermarine Spitfire VA Airplane

Description: Report presenting an investigation of the stalling characteristics of the Supermarine Spitfire, which was made as part of the flying-qualities measurement of the airplane. The results are presented in the form of time histories of the motions and controls during stalls in various conditions of flight. Generally, the Spitfire possessed good stall warning in the form of buffeting and stall motions were not violent.
Date: September 1942
Creator: Vensel, J. R. & Phillips, W. H.
Partner: UNT Libraries Government Documents Department

Crosswell seismic measurement of transverse isotropy in V/sub p/ and Q/sup p/

Description: Crosswell seismic measurements of apparent seismic Q/sub p/, V/sub p/, and V/sub s/ were made at the DOE Multi-Well Experiment (MWX) site near Rifle, Colorado. The MWX wells penetrate gas-bearing low permeability sandstones in the Mesa Verde formation at depths between 1950-2010 meters. Numerous measurements of Q/sub p/ were made between angles of 45 and 135 degrees measured from vertical using a modification of the technique of Fehler and Pearson (1984) in which measurement of P-wave amplitude permits the calculation of Q/sub p/, once compensation has been made for the radiation pattern of the source and geometric spreading. The magnitude of Q/sub p/ and V/sub p/ are found to change with propagation angle. Minimum values of Q/sub p/ and maximum values of V/sub p/ were measured parallel to sedimentary layering (15 and 4.75 km/s, respectively). A roughly linear increase in Q/sub p/ and a decrease in V/sub p/ occurs with increasing inclination of propagation paths to horizontal bedding planes. At 50 degrees from vertical a 90 percent increase in Q/sub p/ and a 7 percent decrease in V/sub p/ relative to values in the horizontal direction were measured. No change in V/sub s/ was observed. 12 refs., 3 figs., 1 tab.
Date: January 1, 1986
Creator: Johnson, P.A.; Albright, J.N. & Phillips, W.S.
Partner: UNT Libraries Government Documents Department

Analysis of turbojet-engine controls for afterburning starting

Description: From Introduction: "The object of this report is to investigate the effects of after-burner lighting on the engine behavior and control-system requirements of a controlled turbojet engine. In this report, a simulation procedure for the afterburner is developed (based on ref. 3), this afterburner simulation is coordinated with previously developed nonafterburning-engine simulation procedures (ref. 4), and the compensated interacting control systems of references 1 and 2 are used. The results of an analog investigation of the the effects of an afterburner light on several controlled turbojet-engine configurations are reported and evaluated."
Date: October 8, 1956
Creator: Phillips, W. E., Jr.
Partner: UNT Libraries Government Documents Department

Temperature-control study of turbine region of turbojet engine, including turbine-blade time constants and starting characteristics

Description: Report presenting an investigation of a turbojet engine in an altitude test facility to supplement existing data relevant to gas-temperature control in a turbojet engine. The problems associated with gas-temperature control for minimizing turbine-blade damage are considered in the report.
Date: April 25, 1956
Creator: Phillips, W. E., Jr.
Partner: UNT Libraries Government Documents Department

Flight Tests of Various Tail Modifications on the Brewster XSBA-1 Airplane 2: Measurements of Flying Qualities with Tail Configuration Number Two

Description: Several tail modifications of the Brewster XSBA-1 scout-bomber were investigated and results compared. Modifications consisted of variation of the chord of the elevator and rudder while the total area of the surfaces is kept constant and variations of the total area of the vertical tail surface. Configuration number 2 reduced trim changes by 50 percent and reduced average elevator control force gradient from 30 to 27 pounds/g. Stick travel required to stall in maneuver was 4.6 inches.
Date: December 1943
Creator: Phillips, W. H. & Crane, H. L.
Partner: UNT Libraries Government Documents Department

Thermal, structural, and fabrication aspects of diamond windows for high power synchrotron x-ray beamlines

Description: Recent advances in chemical vapor deposition (CVD) technology have made it possible to produce thin free-standing diamond foils that can be used as the window material in high heat load, synchrotron beamlines. Numerical simulations suggest that these windows can offer an attractive and at times the only altemative to beryllium windows for use in third generation x-ray synchrotron radiation beamlines. Utilization, design, and fabrication aspects of diamond windows for high heat load x-ray beamlines are discussed, as are the microstructure characteristics bearing on diamond`s performance in this role. Analytic and numerical results are also presented to provide a basis for the design and testing of such windows.
Date: December 1, 1992
Creator: Khounsary, A. M. & Phillips, W.
Partner: UNT Libraries Government Documents Department

The White Pine Mine explosively induced, controlled collapse experiment

Description: On September 3, 1995, the White Pine Mine, which is owned by Copper Range Company, conducted the first of a planned series of explosive removal of existing pillars in their underground mining operations. The purpose of this operation is to evaluate the effectiveness of pillar rubbilization and roof collapse for planned in-situ leaching of the copper ore from the rock mass. This type of seismic source is unique in that a large, delay fired, explosive source was expected to be followed by collapse of the rock immediately above the explosion into the void created. Characterization of this type of mining source is of interest to the Comprehensive Test Ban Treaty (CTBT) R&D Seismic Program due to its unique properties. These include the controlled nature of the source in time, location, and magnitude, the fact that the source is located in an active region of underground mining, and that natural collapse of large portions of this mine have occurred in the recent past. The Mine operator is concerned with the characterization of the vibration induced by both the explosive and implosive components of the procedure and determination of the depth to which chimneying of the roof proceeded. This report will document: The reasons for conducting both the explosively induced collapse and the Los Alamos National Laboratory CTBT R&D Experimental Field Program experiment; The local and regional seismic, acoustic, and videographic data acquired; Analysis of the explosion/collapse seismic signal generated; Analysis and location of the aftershocks associated with the collapse; and Conclusions made concerning this type of mining explosion in relation to verification of a Comprehensive Test Ban Treaty.
Date: September 1996
Creator: Pearson, D. C.; Stump, B. W. & Phillips, W. S.
Partner: UNT Libraries Government Documents Department

Source and path corrections, feature selection, and outlier detection applied to regional event discrimination in China

Description: The authors are investigating techniques to improve regional discrimination performance in uncalibrated regions. These include combined source and path corrections, spatial path corrections, path-specific waveguide corrections to construct frequency-dependent amplitude corrections that remove attenuation, corner frequency scaling, and source region/path effects (such as blockages). The spatial method and the waveguide method address corrections for specific source regions and along specific paths. After applying the above corrections to phase amplitudes, the authors form amplitude ratios and use a combination of feature selection and outlier detection to choose the best-performing combination of discriminants. Feature selection remains an important issue. Most stations have an inadequate population of nuclear explosions on which to base discriminant selection. Additionally, mining explosions are probably not good surrogates for nuclear explosions. The authors are exploring the feasibility of sampling the source and path corrected amplitudes for each phase as a function of frequency in an outlier detection framework. In this case, the source identification capability will be based on the inability of the earthquake source model to fit data from explosion sources.
Date: March 1, 1999
Creator: Hartse, H.E.; Taylor, S.R.; Phillips, W.S. & Velasco, A.A.
Partner: UNT Libraries Government Documents Department

Regional seismic discrimination in central Asia with emphasis on western China

Description: In support of an anticipated Comprehensive Test Ban Treaty, the authors have started to evaluate regional seismic event discrimination capabilities for central Asia, emphasizing western China. The authors have measured noise and seismic phase amplitudes of over 250 earthquakes and 18 underground nuclear explosions recorded at the broadband, digital station WMQ in western China and over 100 earthquakes and 5 nuclear explosions at station AAK in Kyrgyzstan. The explosions are from the Kazakh Test Site (KTS) and Lop Nor, China. The earthquakes are mostly from northwest China. They have also evaluated a single suspected chemical explosion. Event magnitudes (m{sub b}) range between 2.5 and 6.5 and maximum event-station distance is about 1,700 km. Using these measurements the authors formed phase, spectral, cross-spectral, short-period/long-period, and long-period ratios to test many possible event discriminants. All ratios were corrected for distance effects before forming ratio-versus-magnitude discrimination plots. The authors found that all five classes of these discriminants are useful for separating earthquakes from explosions in central Asia, provided the right combinations of frequency bands and phases are selected. Results are described.
Date: September 1, 1996
Creator: Hartse, H.E.; Taylor, S.R.; Phillips, W.S. & Randall, G.E.
Partner: UNT Libraries Government Documents Department

Regional characterization of Western China-II

Description: As part of the CTBT Research and Development regional characterization effort, geological, geophysical, and seismic data are being assembled and organized for inclusion in a knowledge base for China. The authors have continued their analysis using data form the station WMQ of the Chinese Digital Seismic Network (CDSN) and the IRIS station AAK. They are also acquiring and analyzing data from stations that are designated as (or near a designated) primary or secondary CTBT monitoring station. Regional seismograms are being analyzed to construct travel time curves, velocity models, attenuation characteristics, and to quantify regional propagation effects such as phase blockages. Using locations from the USGS Preliminary Determination of Epicenters (PDE) they have identified Pn, Pg, Sn, and Lg phases, constructed travel time curves, and estimated apparent velocities using linear regression. Amplitudes for the seismic phases have been measured using bandpassed waveforms and a series of magnitude relations have been determined for Western China. Studies of path specific propagation efficiency of the seismic phases have mapped blockages and also identified a possible set of observations that can be used to identify intermediate depth (> 100 im) seismic events in the Pamir-Hindu Kush seismic zone. Chinese seismicity catalogs from the USGS and Chinese State Seismological Bureau (SSB) are being used to identify and obtain seismic data (including mine seismicity) and information for lower magnitude events. Clustering analysis has been used to identify seismicity clusters in space with origin times that are distributed during daylight hours which suggest mining operations. These clusters are being investigated with imagery to attempt to identify precise mine locations.
Date: October 1, 1996
Creator: Randall, G.E.; Hartse, H.E.; Phillips, W.S. & Taylor, S.R.
Partner: UNT Libraries Government Documents Department

Identifying structures in clouds of induced microseismic events

Description: A method for finding improved relative locations of microearthquakes accompanying fluid production and injection is presented. The method is based on the assumption that the microearthquake locations are more clustered than found when events are located using conventional techniques. By allowing the rms misfit between measured arrival times and predicted arrival times to increase if events move closer together, the authors find that there is more structure in the pattern of seismic locations. The method is demonstrated using a dataset of microearthquakes induced by hydraulic fracturing. The authors find that structures found using relative arrival times of events having similar waveforms to find improved relative locations of events can also be recovered using the new inversion method but without the laborious repicking procedure. The method provides improved relative locations and hence, an improved image of the structure within the seismic zone that may allow for a better relation between microearthquake locations and zones of increased fluid permeability to be found.
Date: July 1, 1997
Creator: Fehler, M.; House, L. & Phillips, W.S.
Partner: UNT Libraries Government Documents Department

Applying Source and Path Corrections to Improve Discrimination in China,

Description: Monitoring the Comprehensive Test Ban Treaty (CTBT) to magnitude levels below 4.0 will require use of regional seismic data recorded at distances of less than 2000 km. To improve regional discriminant performance we tested three different methods of correcting for path effects, and the third method includes a correction for source-scaling. We used regional recordings of broadband from stations in and near China. Our first method removes trends between phase ratios and physical parameters associated with each event-station path. This approach requires knowledge of the physical parameters along an event-station path, such as topography, basin thickness, and crustal thickness. Our second approach is somewhat more empirical. We examine spatial distributions of phase amplitudes after subtracting event magnitude and correcting for path distance. For a given station, phase, and frequency band, we grid and then smooth the magnitude-corrected and distance-corrected amplitudes to create a map representing a correction surface. We reference these maps to correct phase amplitudes prior to forming discrimination ratios. Our third approach is the most complicated, but also the most rigorous. For a given station and phase, we invert the spectra of a number of well-recorded earthquakes for source and path parameters. We then use the values obtained from the inversion to correct phase amplitudes for the effects of source size, distance, and attenuation. Finally,the amplitude residuals are gridded and smoothed to create a correction surface representing secondary path effects. We find that simple ratio- parameter corrections can improve discrimination performance along some paths (such as Kazakh Test Site (KTS) to WMQ), but for other paths (such as Lop Nor to AAK) the corrections are not beneficial. Our second method, the empirical path correction surfaces, improves discrimination performance for Lop Nor to AAK paths. Our third method, combined source and path corrections, has only been tested at WMQ ...
Date: December 31, 1997
Creator: Hartse, H.E., Taylor, S.R., Phillips, W.S., Randall, G.E.
Partner: UNT Libraries Government Documents Department

The source depth of burial experiment at Shagan River, Kazakstan

Description: The seismic field experimentation team at Los Alamos National Laboratory collaborated with Lawrence Livermore, the Defense Special Weapons Agency (DSWA) and the National Nuclear Center of the Republic of Kazakstan to record the Source Depth of Burial Experiment during the summer of 1997. A series of three 25 ton explosions at depths of 50, 300 and 550 meters along with associated 50 to 100 kg Green`s function explosions and a 5 ton proof of concept explosion were instrumented at near source (0.1 to 20 km) and regional distances (100 to 1,100 km) using portable seismic data acquisition equipment. The near source data represent the first US recordings of seismic data at the former Soviet Union`s Semipalatinsk nuclear test site. The main objective of the Depth of Burial Experiment was to test whether source depth can help identify underground nuclear explosions from observations at distance ranges of 100--1,000 km. A secondary objective was to help calibrate the Kazakstan seismic network, especially the primary IMS station at Makanchi and the auxiliary IMS stations at Kurchatov and Aktyubinsk. Near-source records show the 50 m deep explosion generated much higher amplitude surface (R{sub g}) waves than did either of the deeper explosions. Impulse P-wave arrivals dominated the traces from the 300 and 550 meter deep explosions. P-wave amplitudes, 10--20 Hz, appeared to be a stronger function of source than of path or site. Apparent P velocity was highly path dependent, with higher velocities parallel to the local, NW-SE fabric of the geologic structure. Empirical Green`s function results for the 25 ton shots show increasing corner frequency with depth, consistent with predictions of the Mueller-Murphy source model.
Date: December 31, 1998
Creator: Pearson, D.C.; Phillips, W.S.; Glenn, L.A. & Denny, M.D.
Partner: UNT Libraries Government Documents Department

The Unique Source Mechanism of an Explosively Induced Mine Collapse

Description: Mining explosions and collapses, in addition to earthquakes, may trigger the future Comprehensive Test Ban Treaty (CTBT) monitoring system. Most naturally occurring mine collapses have source mechanisms similar to a closing void which might provide a physical basis to discriminate them from explosions. In this study, an explosively induced mine collapse is investigated. The collapse occurred immediately after the support pillars of an underground mine opening were destroyed by explosives. We estimated the time-dependent source moment tensor of the collapse by inverting the surface ground motion data ({lt}1200 m). The results indicate that the source mechanism of the collapse can be represented by a horizontal crack. A unique source characteristic of the induced collapse is that, unlike natural collapses, the induced collapse initiated as a tensile crack. Because of the initial expansion source mechanism, induced mine collapses may pose some difficulties to the seismic discrimination problem. On the other hand, the collapse has a more band limited source spectrum than a typical underground explosion.
Date: December 31, 1997
Creator: Yang, Xiaoning, Stump, B.W., Phillips, W.S.
Partner: UNT Libraries Government Documents Department