National Advisory Committee for Aeronautics (NACA) - 13,786 Matching Results

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Flight Investigation at High Mach Numbers of Several Methods of Measuring Static Pressure on an Airplane Wing

Description: Report discusses an investigation into static pressures in subsonic and supersonic flow over an airplane wing as measured by static-pressure tubes, a static-pressure belt, and orifices flush with the wing surface. The results obtained from the three types of measuring devices and a comparison to theoretical calculations are presented.
Date: November 1944
Creator: Zalovcik, John A. & Daum, Fred L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight Investigation at High Speeds of Profile Drag of Wing of a P-47d Airplane Having Production Surfaces Covered With Camouflage Paint

Description: Report presenting a flight investigation made at high speeds to determine the profile drag of a P-47D airplane wing with production surfaces covered with camouflage paint. The results indicated that a minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach numbers less than 0.67.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight Investigation at High Speeds of Profile Drag of Wing of a P-47D Airplane Having Production Surfaces Covered with Camouflage Paint

Description: Wing section outboard of flap was tested by wake surveys in Mach range of 0.25 - 0.78 and lift coefficient range 0.06 - 0.69. Results indicated that minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach less than 0.67. Below Mach number at which compressibility shock occurred, variations in Mach of 0.2 had negligible effect on profile drag coefficient. Shock was not evident until critical Mach was exceeded by 0.025.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some Flight Measurements of Pressure-Distribution and Boundary-Layer Characteristics in the Presence of Shock

Description: Memorandum presenting some pressure-distribution and boundary-layer measurements made in flight in the presence of shock on two modifications of the local contour of the wings of a high-speed airplane. Results regarding the pressure distribution, boundary-layer surveys, and effects on test airplane are provided.
Date: July 23, 1948
Creator: Zalovcik, John A. & Luke, Ernest P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Longitudinal Stability and Control Characteristics of a Semispan Airplane Model With a Swept-Back Tail From Tests at Transonic Speeds by the NACA Wing-Flow Method

Description: Report presenting an investigation using the NACA wing-flow method to determine the longitudinal stability and control characteristics of a semispan airplane model with a wing of conventional plan form and a horizontal tail swept back 45 degrees at transonic speeds. Measurements were made of lift and angle of attack for trim at several stabilizer and elevator settings.
Date: March 28, 1947
Creator: Zalovcik, John A. & Sawyer, Richard H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight Investigation of Boundary-Layer Transition and Profile Drag of an Experimental Low-Drag Wing Installed on a Figher-Type Airplane

Description: Report presenting a boundary-layer-transition and profile-drag investigation conducted on an experimental low-drag wing installed on a P-47 airplane designated the XP-47F. Measurements were made at a section outside the propeller slipstream with smooth and with standard camouflage surfaces and on the upper surface of a section in the propeller slipstream with the surface smoothed. Results regarding the right wing section outside the slipstream and left wing section in the propeller slipstream a… more
Date: April 1945
Creator: Zalovcik, John A. & Skoog, Richard B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of the Effect of Surface Roughness on Wing Profile Drag With Transition Fixed

Description: Report presenting a flight investigation made on a wing section of a P-47D airplane to determine the effect of roughness on wing profile drag with transition fixed far forward. Surveys of the wake were made for two surface conditions with transition fixed by a thread at 5 percent chord back of the leading edge on the upper and lower surfaces. Below the Mach number at which shock occurred, variations in Mach number of as much as 0.16 appeared to have no appreciable effect on the section profile-… more
Date: September 1944
Creator: Zalovcik, John A. & Wood, Clotaire
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Static-Pressure Error of an Airspeed Installation on an Airplane in High-Speed Dives and Pullouts

Description: "Tests were made in high-speed dives and pull-outs to determine, by combined radar-optical tracking equipment, the static-pressure error of an airspeed-head installation on a P-51B airplane." The equipment used and testing procedure are described. The variation of static-pressure error is provided for several ranges of airplane lift coefficient.
Date: February 1946
Creator: Zalovcik, John A. & Wood, Clotaire
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A method of calibrating airspeed installations on airplanes at transonic and supersonic speeds by the use of accelerometer and attitude-angle measurements

Description: A method is described for calibrating airspeed installation on airplanes at transonic and supersonic speeds in vertical-plane maneuvers in which use is made of measurements of normal and longitudinal accelerations and attitude angle. In this method all the required instrumentation is carried within the airplane. An analytical study of the effects of various sources of error on the accuracy of an airspeed calibration by the accelerometer method indicated that the required measurements can be mad… more
Date: December 5, 1952
Creator: Zalovcik, John A.; Lina, Lindsay J. & Trant, James P., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight Investigation of Boundary-Layer Control by Suction Slots on an NACA 35-215 Low-Drag Airfoil at High Reynolds Numbers

Description: Report presenting an investigation of the effectiveness of suction slots as a means of extending the laminar boundary layer in flight at high Reynolds numbers on an NACA 35-215 airfoil. The results showed that, with a slot spacing of about 5 percent of the chord, the laminar boundary layer could be maintained to or slightly beyond 45 percent of the chord.
Date: February 1944
Creator: Zalovcik, John A.; Wetmore, J. W. & von Doenhoff, Albert E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight investigation of boundary-layer control by suction slots on an NACA 35-215 low-drag airfoil at high Reynolds numbers

Description: Report presenting an investigation of the effectiveness of suction slots a a means of extending the laminar boundary layer in flight at high Reynolds numbers using an NACA 35-215 airfoil. Tests were made over a range of indicated airspeeds, lift coefficients, and Reynolds numbers. Results regarding boundary-layer control, air-intake distributions, character of the boundary layer, total-intake rate, and profile-drag coefficient are provided.
Date: February 1944
Creator: Zalovcik, John A.; Wetmore, J. W. & von Doenhoff, Albert E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Artificial Aging of Riveted Joints Made in Alclad 24S-T Sheet Using A17S-T, 17S-T, and 24S-T Rivets

Description: Note presenting an investigation of the effect of artificial aging on the strengths of driven rivets of the alloys used commercially for rivets: specifically, A17S-T, 17S-T, and 24S-T. The change in shear strength for each type of rivet after being exposed to artificial aging treatment of 10 hours at 375 degrees Fahrenheit applied to the driven rivets is described.
Date: September 1944
Creator: Zamboky, A. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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System Analyses and Autopilot Design for Automatic Roll Stabilization of a Supersonic Pilotless Aircraft

Description: Memorandum presenting system analyses and autopilot design procedure for a supersonic pilotless aircraft with twin jet engines. The autopilots investigated were a gyro-actuated control, a gyro-actuated control with a rate-sensing device, and an electronic-hydraulic autopilot. Results regarding the airframe and gyro-actuated control system; airframe, gyro-actuated control, and rate servo; airframe and electronic-hydraulic autopilot; and contribution of method of analysis to system design are pro… more
Date: July 11, 1951
Creator: Zarovsky, Jacob
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight investigation of a roll-stabilized missile configuration at varying angles of attack at Mach numbers between 0.8 and 1.79

Description: A missile research model was flown at supersonic speed to determine the quality of automatic roll stabilization at varying angles of attack. Aerodynamic rolling and pitching derivatives were determined from the flight record. It was concluded that the combination of the gyro-actuated automatic pilot with wing-tip ailerons provided adequate roll stabilization under conditions encountered in flight.
Date: January 1957
Creator: Zarovsky, Jacob & Gardiner, Robert A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rocket Power Plants Based on Nitric Acid and their Specific Propulsive Weights

Description: "Two fields are reserved for the application of rocket power plants. The first field is determined by the fact that the rocket power plant is the only type of power plant that can produce thrust without dependence upon environment. The second field is that in which the rocket power plant proves itself the most suitable as a high-power drive in free competition with other types of power plants" (p. 1).
Date: May 1947
Creator: Zborowski, Helmut
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Kinetics of Chemical Reactions in Flames

Description: In part I of the paper the theory of flame propagation is developed along the lines followed by Frank-Kamenetsky and one of the writers. The development of chain processes in flames is considered. A basis is given for the application of the method of stationary concentrations to reactions in flames; reactions with branching chains are analyzed. The case of a diffusion coefficient different from the coefficient of temperature conductivity is considered.
Date: June 1946
Creator: Zeldovich, Y. & Semenov, N. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Theory of Combustion of Initially Unmixed Gases

Description: The chemical reaction of two substances (fuel and oxygen) accompanied by the formation of new substances of the products of combustion and the liberation of heat is considered. General equations are provided as well as an analysis of the equation and the distribution of products of the reaction.
Date: June 1951
Creator: Zeldovich, Y. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Theory of the Propagation of Detonation in Gaseous Systems

Description: "The existing theory of detonation is critically examined. It is shown that the considerations with which the steady value of the velocity of detonation is chosen are not convincing. In connection with the problem of the process of the chemical reaction in a detonation wave, the objections raised against the conceptions of Le Chatelier and Vieille of the 19th century with regard to the ignition of the gas by the shock wave are refuted" (p. 1).
Date: November 1950
Creator: Zeldovich, Y. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Flame Propagation

Description: "The mechanism of flame propagation has been qualitatively formulated. In accordance with this formulation, the chemical reaction initiated in some layer brings about an increase in the temperature; because of the heat conduction, the temperature is raised in the neighboring layer where in turn the chemical reaction is initiated. In this manner the flame is propagated" (p. 1).
Date: June 1951
Creator: Zeldovich, Y. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent Development of the Two-Stroke Engine 2 - Design Features

Description: "Completing the first paper dealing with charging methods and arrangements, the present paper discusses the design forms of two-stroke engines. Features which largely influence piston running are: (a) The shape and surface condition of the sliding parts. (b) The cylinder and piston materials. (c) Heat conditions in the piston, and lubrication. There is little essential difference between four-stroke and two-stroke engines with ordinary pistons" (p. 1).
Date: May 1945
Creator: Zeman, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Two-Stroke-Cycle Engines With Unsymmetrical Control Diagram (Supercharged Engines)

Description: As no investigation of supercharging in 2-stroke-cycle engines has been published up to the present, this article is an attempt in that direction, with a view to establishing the mathematical principles and the constructive rules for the design of such engines.
Date: September 1939
Creator: Zeman, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stress and Distortion Measurements in a 45 Degree Swept Box Beam Subjected to Bending and to Torsion

Description: Note presenting an untapered aluminum-alloy box beam, representing the main structural component of a full-span, two-spar, 45 degree swept wing with a carry-through bay, was subjected to tip bending and twisting loads and its stresses and distortions were measured. The investigation revealed that for bending, the important effect of sweep was to cause a considerable build-up of normal stress and vertical shear stress in the rear spar near the fuselage.
Date: March 1948
Creator: Zender, George & Libove, Charles
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of theoretical stresses and deflections of multicell wings with experimental results obtained from plastic models

Description: The experimental deflections and stresses of six plastic multicell-wing models of unswept, delta, and swept plan form are presented and compared with previously published theoretical results obtained by the electrical analog method. The comparisons indicate that the theory is reliable except for the evaluation of stresses in the vicinity of the leading edge of delta wings and the leading and trailing edges of swept wings. The stresses in these regions are questionable, apparently because of sim… more
Date: November 1956
Creator: Zender, George W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Approximate Method of Calculating the Deformations of Wings Having Swept, M or W, A, and Swept-Tip Plan Forms

Description: "An approximate method of calculating the deformations of wings of uniform thickness having swept, M or W, Delta, and swept-tip plan forms is presented. The method employs an adjustment to the elementary beam theory to account for the effect of the triangular root portion of a swept wing on the deformation of the outboard section of the wing. To demonstrate the general applicability of the method, the modified elementary theory is applied to the more complex M or W, Delta, and swept-tip plan fo… more
Date: 1952
Creator: Zender, George W. & Brooks, William A., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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