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Preliminary Altitude Performance Data of J71-A2 Turbojet Engine Afterburner

Description: The performance and operational characteristics of the J71-A2 turbojet-engine afterburner were investigated for a range of altitudes from 23,000 to 60,000 feet at a flight Mach number of 0,9 and at flight Mach numbers of 0.6, 0.9, and 1.0 at an altitude of 45,000 feet. The combustion performance and altitude operational limits, as well as the altitude starting characteristics have been determined.
Date: October 7, 1954
Creator: Useller, James W. & Mallett, William E.

Preliminary analysis of a nuclear powered supersonic airplane using ramjet engines

Description: Report discussing performance estimates for several airplanes using General Electric AC-210 ramjet nuclear-powered engines. Assumptions used for designing the engines, radiation shield, and airframe are described. Potential tradeoffs in regards to power and weight reduction are also discussed.
Date: April 11, 1958
Creator: Weber, Richard J. & Connolley, Donald J.

Preliminary Analysis of Axial-Flow Compressors Having Supersonic Velocity at the Entrance of the Stator

Description: A supersonic compressor design having supersonic velocity at the entrance of the stator is analyzed on the assumption of two-dimensional flow. The rotor and stator losses assumed in the analysis are based on the results of preliminary supersonic cascade tests. The results of the analysis show that compression ratios per stage of 6 to 10 can be obtained with adiabatic efficiency between 70 and 80 percent. Consideration is also given in the analysis to the starting, stability, and range of efficient performance of this type of compressor. The desirability of employing variable-geometry stators and adjustable inlet guide vanes is indicated. Although either supersonic or subsonic axial component of velocity at the stator entrance can be used, the cascade test results suggest that higher pressure recovery can be obtained if the axial component is supersonic.
Date: September 12, 1949
Creator: Ferri, Antonio

Preliminary analysis of effects of air cooling turbine blades on turbojet-engine performance

Description: The effects of turbine-blade cooling on engine performance were analytically investigated for a turbojet engine in which cooling air is bled from the engine compressor. The analysis was made for a constant turbine-inlet temperature and a range of altitudes to determine the minimum cooling requirements to permit substitution of nonstrategic materials in turbine blading. The results indicate that, for a constant inlet temperature, air cooling of the turbine blades increases the specific fuel consumption and decreases the thrust of the engine. The highest possible cooling effectiveness is desirable to minimize coolant weight flow and its effects on engine performance.
Date: August 2, 1950
Creator: Schramm, Wilson B; Nachtigall, Alfred J & Arne, Vernon L

Preliminary analysis of hydrogen-rich hypersonic ramjet operation

Description: Report discussing findings on net thrust, fuel flow, and related performance indices for hydrogen-rich operation of nacelle-type and submerged ramjet engines at various Mach numbers. Testing concluded that the system could be helpful in a flight path involving acceleration from low to high flight speeds. Some trends of the effect of the operation conditions are noted, but no conclusions are drawn because of the preliminary nature of the report.
Date: January 14, 1958
Creator: Breitwieser, Roland & Morris, James F.

Preliminary analysis of NACA measurements of atmospheric turbulence within a thunderstorm - U.S. Weather Bureau thunderstorm project

Description: A general description of the field operations of the U.S. Weather Bureau thunderstorm project conducted in the vicinity of Orlando, Florida during the summer month of 1946 is given. The participation of NACA in this project is described and measurements of atmospheric turbulence taken by NACA are presented for one of the flights. The results indicate that some regions of thunderstorms may present no great hazard to flight, while exceptionally severe conditions of atmospheric turbulence may occur in other regions, or even in the same region, at about the same time. The results also indicate that these severe conditions of turbulence might lead to loss of control with the possible loss of the airplane.
Date: March 1, 1947
Creator: Tolefson, Harold B

Preliminary Analysis of Ore Distribution in the Gateway and Uravan Districts, Mesa and Montrose Counties, Colorado

Description: From abstract: The distribution of the known uranium deposits of the Colorado Plateau is being analyzed in order 1) to test for systematic relationships between that pattern and geologic factors, 2) to help guide exploration, and 3) to appraise the potential resources of the region and of each of its component areas.
Date: April 1954
Creator: Strobell, J. D., Jr.; Sample, R. D.; Stephens, H. G. & Gilbert, Cynthia C.

Preliminary analysis of problem of determining experimental performance of air-cooled turbine I : methods for determining heat-transfer characteristics

Description: In determining the experimental performance of an air-cooled turbine, the heat-transfer characteristics must be evaluated. The suggested formulas that are required to determine these characteristics are presented. The formulas have a form in which dependent parameters are expressed as unknown functions of independent parameters. Methods of experimenting to determine these functions are suggested. In some cases general heat-transfer discussions that lead to the suggested forms of the formulas are given.
Date: June 12, 1950
Creator: Ellerbrock, Herman H., Jr. & Ziemer, Robert R.

Preliminary analysis of problem of determining experimental performance of air-cooled turbine II : methods for determining cooling-air-flow characteristics

Description: In the determination of the performance of an air-cooled turbine, the cooling-air-flow characteristics between the root and the tip of the blades must be evaluated. The methods, which must be verified and the unknown functions evaluated, that are expected to permit the determination of pressure, temperature, and velocity through the blade cooling-air passages from specific investigation are presented.
Date: June 7, 1950
Creator: Ellerbrock, Herman H., Jr.

Preliminary analysis of problem of determining experimental performance of air-cooled turbine III : methods for determining power and efficiency

Description: Suggested formula are given for determining air-cooled turbine-performance characteristics, such as power and efficiency, as functions of certain parameters. These functions, generally being unknown, are determined from experimental data obtained from specific investigations. Special plotting methods for isolating the effect of each parameter are outlined.
Date: August 2, 1950
Creator: Ellerbrock, Herman H., Jr. & Ziemer, Robert R.

A Preliminary Analysis of the Flying Qualities of the Consolidated Vultee MX-813 Delta-Wing Airplane Configuration at Transonic and Low Supersonic Speeds as Determined from Flights of Rocket-Powered Models

Description: A preliminary analysis of the flying qualities of the Consolidated Vultee MX-813 delta-wing airplane configuration has been made based on the results obtained from the first two 1/8 scale models flown at the NACA Pilotless Aircraft Research Station, Wallop's Island, VA. The Mach number range covered in the tests was from 0.9 to 1.2. The analysis indicates adequate elevator control for trim in level flight over the speed range investigated. Through the transonic range there is a mild trim change with a slight tucking-under tendency. The elevator control effectiveness in the supersonic range is reduced to about one-half the subsonic value although sufficient control for maneuvering is available as indicated by the fact that 10 deg elevator deflection produced 5g acceleration at Mach number of 1.2 at 40,000 feet.The elevator control forces are high and indicate the power required of the boost system. The damping. of the short-period oscillation is adequate at sea-level but is reduced at 40,000 feet. The directional stability appears adequate for the speed range and angles of attack covered.
Date: 1949
Creator: Mitcham, Grady L.

Preliminary analysis of three cycles for nuclear propulsion of aircraft

Description: A preliminary study was made of the feasibility of three cycles for nuclear propulsion of aircraft: a direct-air-turbojet, a binary liquid-metal turbojet, and a helium compressor jet. All three cycles appeared feasible for flight at a Mach number of 0.9 and altitudes up to 50,000 feet; the liquid-metal cycle appeared feasible for flight at a Mach number of 1.5. The air and helium cycles resulted in heavier aircraft than did the liquid-metal cycle, particularly at a Mach number of 1.5. The relative advantage of the liquid-metal cycle became greater as the flight speed and altitude increased, and as the reactor wall temperature decreased.
Date: October 13, 1950
Creator: Humble, L V; Wachtl, W W & Doyle, R B

Preliminary Applications of Landsat Images and Aerial Photography for Determining Land-Use, Geologic, and Hydrologic Characteristics--Yampa River Basin, Colorado and Wyoming

Description: From abstract: "This study used Landsat images and small-scale color and color-infrared photographs for selected geologic, hydrologic, and land-use applications within the Yampa River Basin" in Colorado and Wyoming. It includes maps, tables, and a glossary.
Date: October 1978
Creator: Heimes, Frederick J.; Moore, Gerald K. & Steele, Timothy Doak

Preliminary Appraisal of Diamond-Drill Exploration in the Legin Group Area, San Miguel County, Colorado

Description: From introduction: This preliminary report summarizes the results of the 1950 drilling in the Legin group area of San Miguel County, Colorado and gives a more complete, but preliminary, estimate of the uranium and vanadium ore reserves. When the radiometric and chemical assay data are completed, a detailed report will be transmitted.
Date: February 1951
Creator: Bell, Henry

Preliminary Appraisal of Ferrocene as an Igniting Agent for JP-4 Fuel and Fuming Nitric Acid

Description: A preliminary experimental study was made of the properties of ferrocene as a solute and as a suspension in JP-4 fuel, and of the ignition delays of ferrocene - JP-4 mixture with A.F. specification 14104 white fuming nitric acid (WFNA). The investigation covered concentrations of 4 to 10 percent by weight ferrocene, and a temperature range of -40 to 80 F. The solubility of ferrocene in JP-4 is about 5 percent at room temperature and about 1 percent (extrapolated) at -80 F. The solubility is increased somewhat by increased aromatics content. Undissolved ferrocene particles of 100 mesh and smaller settle rapidly in JP-4. Clear solutions of 4 and 5 percent ferrocene in JP-4 fuels containing 10 and 25 percent by volume aromatics, respectively, do not ignite with WFNA at room temperature. Mixtures containing 10 percent ferrocene (100- mesh and smaller undissolved particles in suspension) ignited with vigorous persistent flames at room temperature, but did not ignite at -38 F. The ignition delays at room temperature, however, were widely varied; the range from 85 milliseconds to over 1 second perhaps reflected differences in degree of sedimentation.
Date: August 25, 1953
Creator: Miller, RIley O.

A Preliminary Appraisal of Sediment Sources and Transport in Kings Bay and Vicinity, Georgia and Florida

Description: From introduction: This report reviews descriptive background information of the Kings Bay area and presents data on currents, salinity, temperature, turbidity, suspended sediment, phytoplankton, and on the chemical and physical characteristics of bottom sediments. Water, salt, and suspended-sediment discharges are computed for consecutive ebbtides and floodtides that occurred during the November investigation.
Date: 1983
Creator: McConnell, James B.; Radtke, Dean B.; Hale, Timothy W. & Buell, Gary R.

Preliminary Appraisal of the Carnotite Resources of the Carrizo Mountains Area, San Juan County, New Mexico, and Apache County, Arizona

Description: From introduction: A rapid appraisal of the carnotite resources of the Salt Wash sandstone member of the Morrison formation in the Carrizo Mountains area was undertaken by the U. S. Geological Survey late in 1951 in connection with its current project of geologic mapping of the area. Though brief and preliminary, this report provides a summary of production trends and estimated reserves in the area and indicates as far as possible the total potential of the area as a source of uranium. This information may be helpful in planning new milling facilities or other measures to encourage a higher rate of production.
Date: May 1952
Creator: Strobell, J. D.

Preliminary Appraisal of the Hydrology of the Rock Island Area, Le Flore County, Oklahoma

Description: From introduction: The purpose of this report is to describe the hydrology and potential impacts of mining in the vicinity of the town of Rock Island in northeastern Le Flore County where the upper and lower Harshorne coals are at or near the surface and amenable to surface mining.
Date: 1983
Creator: Marcher, Melvin V.; Bergman, DeRoy L. & Stoner, Jerry D.