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open access

Additional free-flight tests of the rolling effectiveness of several wing-spoiler arrangements at high subsonic, transonic, and supersonic speeds

Description: From Introduction: "The purpose of the present paper is to present results obtained recently relating to the characteristics of a full-span sharp-edge spoiler with an 0.02-chord projection above the wing surface at several chordwise positions and also to the relative effectiveness of the sharp-edge spoiler and a wedge-type spoiler located at the 80-percent-chord line."
Date: November 24, 1948
Creator: Strass, H. Kurt
open access

Analysis of Effects of Inlet Pressure Losses on Performance of Axial-Flow Type Turbojet Engine

Description: From Introduction: "An analytical evaluation of the effects of inlet losses on the net thrust and the fuel economy of an axial-flow-compressor type turbojet engine with a two-stage turbine is presented herein. The analysis is based on engine performance characteristics that were determined from experiments in the NACA Cleveland altitude wind tunnel (references 1 and 2). The experimental investigation did not include tests in which inlet losses were systematically varied, but the effects of thes… more
Date: November 24, 1948
Creator: Sanders, Newell D. & Palasics, John
open access

Application of one part of Von Karman's two-dimensional transonic similarity law to drag data of NACA 65-series wings

Description: Report presenting the use of Von Karman's two-dimensional transonic similarity law as applied to drag data of three different thickness wings with NACA 65-series sections and aspect ratios of 7.6 over a range of Mach numbers. The correlation was found to be satisfactory, with results better in the subsonic range than in the supersonic range.
Date: August 24, 1948
Creator: Amer, Kenneth B.
open access

Calculation of the Aerodynamic Loading of Flexible Wings of Arbitrary Plan Form and Stiffness

Description: "A method is presented for calculating the aerodynamic loading, the divergence speed, and certain stability derivatives of wings and tail surfaces of arbitrary plan form and stiffness. Provision is made for using either stiffness curves and root-rotation constants or influence coefficients in the analysis. Computing forms, tables of numerical constants required in the analysis, and an illustrative example are included to facilitate calculations by means of the method" (p. 1).
Date: December 24, 1948
Creator: Diederich, Franklin W.
open access

Calculation of the aerodynamic loading of swept and unswept flexible wings of arbitrary stiffness

Description: A method is presented for calculating the aerodynamic loading, the divergence speed, and certain stability derivatives of swept and unswept wings and tail surfaces of arbitrary stiffness. Provision is made for using either stiffness curves and root rotation constants or structural influence coefficients in the analysis. Computing forms, tables of numerical constants required in the analysis, and an illustrative example are included to facilitate calculations by means of the method.
Date: December 24, 1948
Creator: Diederich, Franklin W.
open access

Current Status of Longitudinal Stability

Description: Report presenting an investigation of the problems of static and dynamic longitudinal stability both at high speeds and low speeds as well as information about progress that has been made to solve these problems. The incorporation of large amounts of sweepback on both the wing and horizontal tail can improve the rate of trim changes and stability. Longitudinal stability has been attained for configurations with a sweep angle of 45 degrees with stall-control devices, but experimental proof is ne… more
Date: May 24, 1948
Creator: Donlan, Charles J.
open access

Degradation of Isotopic Lactate and Acetate

Description: A scheme of glucose degradation has been validated by the use of intermediates of known isotopic composition. In this scheme: glucose {yields} lactic acid {yields} CO{sub 2} (C-3,4) + acetic acid {yields} CO{sub 2} (C-2,5) + acetone {yields} iodoform (C-1,6) + acetate (C-1,6; 2,5), it was found that (a) in the oxidation of lactic acid, approximately 4.7% of the acetic acid was oxidized to CO{sub 2}; and (b) under the conditions prescribed, BaCO{sub 3} from the degradation of Ba acetate containe… more
Date: February 24, 1948
Creator: Aronoff, S.; Haas, V. A. & Fries, B. A.
open access

Effect of Distribution of Basket-Hole Area on Simulated Altitude Performance of 25 1/2-Inch-Diameter Annular-Type Turbojet Combustor

Description: A simulated altitude performance of a 25 1/2-inch-diameter annular-type turbojet combustor was performed to determine the effect of the distribution of basket-hole area on the altitude operational limits of the engine as imposed by the combustor.Total pressure drop was recorded, as well as the effect of fuel-nozzle flow capacity,and fuel-nozzle spray angle for one basket configuration. General observations were made for all configurations regarding flames, extent of afterburning, and durability… more
Date: August 24, 1948
Creator: Olson, Walter T. & Schroeter, Thomas T.
open access

Effect of three flame-holder configurations on subsonic flight performance of rectangular ram jet over range of altitudes

Description: Report presenting a flight investigation on a rectangular ram jet over a range of fuel air ratios, combustion chamber inlet velocities, and pressure altitudes. A comparative study to determine the effects of altitude, combustion-chamber-inlet velocity, and fuel-air ratio on starting characteristics, minimum blow-out limits, combustion efficiency, gas total-temperature ratio, and net-thrust coefficient for three flame holders was also conducted.
Date: November 24, 1948
Creator: Black, Dugald O. & Messing, Wesley E.
open access

Effect of variation in fuel pressure on combustion performance of rectangular ram jet

Description: Report presenting the results of an investigation on a rectangular ram jet to determine the effect of variation in fuel pressure on the starting characteristics, minimum blow-out limits, combustion efficiencies, gas total-temperature ratio, and net-thrust coefficient. Testing occurred using three different fuel nozzles and over a range of pressure altitudes, airspeeds, and fuel-air ratios.
Date: November 24, 1948
Creator: Messing, Wesley E. & Black, Dugald O.
open access

Graphite contaminant tests for DR&H piles (C-206A, HW24, C-165A, HW24)

Description: This report outlines plans for tests of the graphite stack during lay up in the pile structures. Measurements are planned upon completion of layers 20, 60, and 102, which will require not more than 16 hours each. The test method will require restriction of Construction personnel from the areas immediately adjacent to the pile. Precise boundaries will be set up in collaboration with H I Division personnel prior to the test.
Date: June 24, 1948
Creator: Burns, J. A.
open access

The Half-Lives of Aluminum25 and Aluminum26

Description: The availability of separated isotopes of Mg makes it easy to determine the half life of Al{sup 26}, a member of the Wigner series which has long been suspected to have a half life of approximately 7 seconds, but which has not been confirmed because of the masking 7 second activity of Al{sup 26}. Mg{sup 24}, Mg{sup 25} and Mg{sup 26} (in the form of MgO) have been bombarded with protons from the Berkeley Linear Accelerator, with the following results: (1) Mg{sup 24} yields an activity of approx… more
Date: April 24, 1948
Creator: Bradner, Hugh & Gow, J.D.
open access

High Voltage Pulsar For 184-inch Cyclotron Electric Deflector

Description: This paper describes a high voltage pulse generator developed to deflect the beam of the 184-inch cyclotron at Berkeley, California. The apparatus develops a deflecting potential of 200 kilovolts that rises from 10% to 90% of peak value in 0.1 microseconds. The unit employs two similar 100 kilovolt water cooled pulse transformers connected symmetrically about ground to the electric deflector bars. Water-cooled General Electric pulse capacitors are discharged through the two turn primary winding… more
Date: April 24, 1948
Creator: Kerns, Q. A.; Baker, W. R.; Edwards, R. F. & Farly, G. M.
open access

Investigation at supersonic speed (M = 1.53) of the pressure distribution over a 63 degrees swept airfoil of biconvex section at several angles of attack

Description: Report presenting the results of an investigation at supersonic speed of the distribution of pressure over the surface of a swept airfoil of biconvex section at various angles of attack. The measurements are compared with supersonic lifting-surface theory, which generally indicated good agreement except over the regions of the airfoil influenced by the subsonic trailing edge and the tips. Results regarding the pressure distribution, boundary-layer studies, and normal force and pitching moment a… more
Date: September 24, 1948
Creator: Katzen, Elliott D.; Frick, Charles W. & Boyd, John W.
open access

Investigation of spark gaps subjected to altitude and air velocity conditions

Description: Report presenting a study of the effects of air velocity on the energy and power of the spark in a constant ignition source and the duration of the spark discharge in the spark gap for various conditions of electrode spacing, electrode diameter, air temperature, and pressure. Energy and average power increased with pressure, velocity, and electrode spacing and electrode diameter and air temperature had negligible effect.
Date: November 24, 1948
Creator: Swett, Clyde C., Jr.
open access

Investigation of the I-40 jet-propulsion engine in the Cleveland altitude wind tunnel 1: performance and windmilling drag characteristics

Description: Report presenting the performance characteristics of the I-40 jet propulsion engine and an analysis for a range of altitudes and ram pressure ratios. Results regarding the component efficiencies, engine performance, generalizing factors, and windmilling drag characteristics are provided.
Date: August 24, 1948
Creator: Gendler, Stanley L. & Koffel, William K.
open access

Investigation of the I-40 Jet-Propulsion Engine in the Cleveland Altitude Wind Tunnel 1: Performance and Windmilling Drag Characteristics

Description: Report presenting the performance characteristics of the I-40 jet-propulsion engine for a range of altitudes and ram pressure ratios. Results regarding component efficiencies, engine performance, generalizing factors, and windmilling drag characteristics are provided.
Date: August 24, 1948
Creator: Gendler, Stanley L. & Koffel, William K.
open access

Limited measurements of static longitudinal stability in flight of Douglas D-558-1 airplane (BuAero No. 37971)

Description: Contains a few measurements of the variation of elevator angle and elevator force with Mach number at 30,000 feet altitude up to a Mach number of 0.85. These data show that the airplane possessed positive static longitudinal stability up to a Mach number of 0.80. A trim change in the nose-down direction occurred for Mach numbers above 0.82.
Date: June 24, 1948
Creator: Williams, Walter C.
open access

Low-Speed Investigation of a Small Triangular Wing of Aspect Ratio 2.0 3: Static Stability With Twin Vertical Fins

Description: "Low-speed wind-tunnel tests were made of a triangular wing with two arrangements of twin vertical fins. With these twin fins mounted either symmetrically or wholly above the wing chord plane, approximately constant effectiveness in proportion to the fin size was obtained throughout the angle-of-attack range. The addition of these fins, however, resulted in a decrease in maximum lift and a reduction in static longitudinal stability at lift coefficients above 0.4" (p. 1).
Date: August 24, 1948
Creator: Rose, Leonard M.
open access

Medical and Health Divisions quarterly report, January, February, March 1948

Description: This quarterly progress report describes four programs namely (1) The Metabolic Properties of Plutonium and Allied Materials (2) Biological studies of radiation effects, (3) Biological effects of radiation from external and internal sources, and (4) Health Physics and Chemistry. Progress for each program has been separately indexed and abstracted for the database.
Date: May 24, 1948
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