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Free-spinning wind-tunnel tests of a low-wing monoplane with systematic changes in wings and tails V: effect of airplane relative density

Description: The reported tests are a continuation of an NACA investigation being made in the free-spinning wind tunnel to determine the effects of independent variations in load distribution, wing and tail arrangement, and control disposition on the spin characteristics of airplanes. The standard series of tests was repeated to determine the effect of airplane relative density. Tests were made at values of the relative-density parameter of 6.8, 8.4 (basic), and 12.0; and the results were analyzed. The test… more
Date: January 11, 1940
Creator: Seidman, Oscar & Neihouse, A. I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of Castering Wheels for Aircraft Landing Gears

Description: "A theoretical study was made of the shimmy of castering wheels. The theory is based on the discovery of a phenomenon called kinematic shimmy. Experimental checks, use being made of a model having low-pressure tires, are reported and the applicability of the results to full scale is discussed. Theoretical methods of estimating the spindle viscous damping and the spindle solid friction necessary to avoid shimmy are given. A new method of avoiding shimmy -- lateral freedom -- is introduced" (p. 1… more
Date: August 11, 1937
Creator: Kantrowitz, Arthur
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Two-Dimensional Subsonic Compressible Flow Past Elliptic Cylinders

Description: "The method of Poggi is used to calculate, for perfect fluids, the effect of compressibility upon the flow on the surface of an elliptic cylinder at zero angle of attack and with no circulation. The result is expressed in a closed form and represents a rigorous determination of the velocity of the fluid at the surface of the obstacle insofar as the second approximation is concerned. Comparison is made with Hooker's treatment of the same problem according to the method of Janzen and Rayleight an… more
Date: February 11, 1938
Creator: Kaplan, Carl
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wind-Tunnel and Flight Tests of Slot-Lip Ailerons

Description: "The slot-lip ailerons developed by the NACA consist of a flap-type spoiler with an adjoining continuously open slot. The ailerons were developed in an investigation of the delayed response, or lag, of spoiler-type lateral controls. This report presents the results of tests of these slot-lip ailerons made on wing models in the 7 by 10-foot wind tunnel, on a Fairchild 22 airplane in the full-scale wind tunnel and in flight, and on the Weick W1-A airplane in flight" (p. 537).
Date: June 11, 1937
Creator: Shortal, Joseph A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Factors Affecting Combustion in an Internal-Combustion Engine

Description: "An investigation of the combustion of gasoline, safety, and diesel fuels was made in the NACA combustion apparatus under conditions of temperature that permitted ignition by spark with direct fuel injection, in spite of the compression ratio of 12.7 employed. The influence of such variables as injection advance angle, jacket temperature, engine speed, and spark position was studied. The most pronounced effect was that an increase in the injection advance angle (beyond a certain minimum value) … more
Date: September 11, 1934
Creator: Rothrock, A. M. & Cohn, Mildred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Working Charts for the Determination of the Lift Distribution Between Biplane Wings

Description: "In this report are presented empirical working charts from which the distribution of lift between wings, that is the fraction of the total lift borne by each, can be determined in the positive lift range for any ordinary biplane cellule whose individual wings have the same profile. The variables taken directly into account include airfoil section, stagger, gap/chord ratio, decalage, chord ratio, and overhang. It is shown that the influence of unequal sweepback and unequal dihedral in upper and… more
Date: July 11, 1932
Creator: Kuhn, Paul
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of variation of chord and span of ailerons on hinge moments at several angles of pitch

Description: This report presents the results of an investigation of the hinge moments of ailerons of various chords and spans on two airfoils having the Clark Y and USA-27 wing sections, supplementing the investigations described in NACA-TR-298 and NACA-TR-343, of the rolling and yawing moments due to similar ailerons on these two airfoil sections. The measurements were made at various angles of pitch, but at zero angle of roll and yaw, the wing chord being set at an angle of +4 degrees to the fuselage axi… more
Date: August 11, 1930
Creator: Monish, B. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coefficients of discharge of fuel-injection nozzles for compression-ignition engines

Description: "This report presents the results of an investigation to determine the coefficients of discharge of nozzles with small, round orifices of the size used with high-speed compression-ignition engines. The injection pressures and chamber back pressures employed were comparable to those existing in compression-ignition engines during injection. The construction of the nozzles was varied to determine the effect of the nozzle design on the coefficient. Tests were also made with nozzles assembled in an… more
Date: September 11, 1930
Creator: Gelalles, A. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The comparative performance of an aviation engine at normal and high inlet air temperatures

Description: "This report presents some results obtained during an investigation to determine the effect of high inlet air temperature on the performance of a Liberty 12 aviation engine. The purpose of this investigation was to ascertain, for normal service carburetor adjustments and a fixed ignition advance, the relation between power and temperature for the range of carburetor air temperatures that may be encountered when supercharging to sea level pressure at altitudes of over 20,000 feet and without int… more
Date: February 11, 1927
Creator: Gardiner, Arthur W. & Schey, Oscar W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Normal Component of the Induced Velocity in the Vicinity of a Lifting Rotor and Some Examples of Its Application

Description: "Paper presents a practical method for computing the approximate values of the normal component of the induced velocity at points in the flow field of a lifting rotor. Tables and graphs of the relative magnitudes of the normal component of the induced velocity are given for selected points in the longitudinal plane of symmetry of the rotor and on the lateral rotor axis. A method is also presented for utilizing the tables and graphs to determine the interference induced velocities arising from t… more
Date: August 11, 1952
Creator: Castles, Walter, Jr. & De Leeuw, Jacob Henri
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Method for the Design of Sweptback Wings Warped to Produce Specified Flight Characteristics at Supersonic Speeds

Description: One of the problems connected with the sweptback wing is the difficulty of controlling the location of the center of pressure and hence the pitching moment. A method is presented for designing a wing to be self-trimming at a given set of flight conditions. Concurrently, the spanwise distribution of load on the wing is made to be approximately elliptical, in an effort to maintain low wing drag.
Date: May 11, 1951
Creator: Tucker, Warren A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Propeller charts for the determination of the rotational speed for the maximum ratio of the propulsive efficiency to the specific fuel consumption

Description: A set of propeller operating efficiency charts, based on a coefficient from which the propeller rotational speed has been eliminated, is presented. These charts were prepared with data obtained from tests of full-size metal propellers in the NACA propeller-research tunnel. Working charts for nine propeller-body combinations are presented, including results from tests of dual-rotating propellers. These charts are to be used in the calculation of the range and the endurance of airplanes equipped … more
Date: December 11, 1940
Creator: Biermann, David & Conway, Robert N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Preknock vibrations in a spark-ignition engine cylinder as revealed by high-speed photography

Description: "The high-speed photographic investigation of the mechanics of spark-ignition engine knock recorded in three previous reports has been extended with use of the NACA high-speed camera and combustion apparatus with a piezoelectric pressure pickup in the combustion chamber. The motion pictures of knocking combustion were taken at the rate of 40,000 frames per second. Existence of the preknock vibrations in the engine cylinder suggested in Technical Report no.727 has been definitely proved and the … more
Date: September 11, 1944
Creator: Miller, Cearcy D. & Logan, Walter O., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Summary of Drag Characteristics of Practical-Construction Wing Sections

Description: "The effect of several parameters on the drag characteristics of practical-construction wing sections have been considered and evaluated. The effects considered were those of surface roughness, surface waviness, compressive load, and de-icers. The data were obtained from a number of tests in the Langley two-dimensional low-turbulence tunnels" (p. 359).
Date: July 11, 1946
Creator: Quinn, John H., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Exhaust-stack nozzle area and shape for individual cylinder exhaust-gas jet-propulsion system

Description: This report presents the results of an investigation conducted on the effect of exhaust-stack nozzle area, shape, and length on engine power, jet thrust, and gain in net thrust (engine propeller plus jet). Single-cylinder engine data were obtained using three straight stacks 25, 44, and 108 inches in length; an S-shaped stack, a 90 degree bend, a 180 degree bend, and a short straight stack having a closed branch faired into it. Each stack was fitted with nozzles varying in exit area from 0.91 s… more
Date: August 11, 1942
Creator: Pinkel, Benjamin; Turner, L. Richard; Voss, Fred & Humble, Leroy V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Propellers in yaw

Description: It was realized as early as 1909 that a propeller in yaw develops a side force like that of a fin. In 1917, R. G. Harris expressed this force in terms of the torque coefficient for the unyawed propeller. Of several attempts to express the side force directly in terms of the shape of the blades, however, none has been completely satisfactory. An analysis that incorporates induction effects not adequately covered in previous work and that gives good agreement with experiment over a wide range of … more
Date: October 11, 1943
Creator: Ribner, Herbert S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wind-tunnel investigation of air inlet and outlet openings on a streamline body

Description: In connection with the general problem of providing air flow to an aircraft power plant located within a fuselage, an investigation was conducted in the Langley 8-foot high-speed tunnel to determine the effect on external drag and pressure distribution of air inlet openings located at the nose of a streamline body. Air outlet openings located at the tail and at the 21-percent and 63-percent stations of the body were also investigated. Boundary layer transition measurements were made and correla… more
Date: September 11, 1940
Creator: Becker, John V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Automatic control systems satisfying certain general criterions on transient behavior

Description: "An analytic method for the design of automatic controls is developed that starts from certain arbitrary criterions on the behavior of the controlled system and gives those physically realizable equations that the control system can follow in order to realize this behavior. The criterions used are developed in the form of certain time integrals. General results are shown for systems of second order and of any number of degrees of freedom. Detailed examples for several cases in the control of a … more
Date: October 11, 1950
Creator: Boksenbom, Aaron S. & Hood, Richard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On Panel Flutter and Divergence of Infinitely Long Unstiffened and Ring-Stiffened Thin-Walled Circular Cylinders

Description: "A preliminary theoretical investigation of the panel flutter and divergence of infinitely long, unstiffened and ring-stiffened thin-walled circular cylinders is described. Linearized unsteady potential-flow theory is utilized in conjunction with Donnell's cylinder theory to obtain equilibrium equations for panel flutter. Where necessary, a simplified version of Flugge's cylinder theory is used to obtain greater accuracy. By applying Nyquist diagram techniques, analytical criteria for the locat… more
Date: January 11, 1956
Creator: Leonard, Robert W. & Hedgepeth, John M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Comparison of wind-tunnel and flight measurements of stability and control characteristics of a Douglas A-26 airplane

Description: From Summary: "Stability and control characteristics determined from tests in the Langley 19-foot pressure tunnel of a 0.2375-scale model of the Douglas XA-26 airplane are compared with those measured in flight tests of a Douglas A-26 airplane. Agreement regarding static longitudinal stability as indicated by the elevator-fixed neutral points and by the variation of elevator deflection in both straight and turning flight was found to be good except at speeds approaching the stall. At these low … more
Date: August 11, 1945
Creator: Kayten, Gerald G. & Koven, William
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Initial results of instrument-flying trials conducted in a single-rotor helicopter

Description: "Instrument-flying trials have been conducted in a single-rotor helicopter, the maneuver stability of which could be changed from satisfactory to unsatisfactory. The results indicated that existing longitudinal flying-qualities requirements based on contact flight were adequate for instrument flight at speeds above that for minimum power. However, lateral-directional problems were encountered at low speeds and during precision maneuvers" (p. 1).
Date: March 11, 1952
Creator: Crim, Almer D.; Reeder, John P. & Whitten, James B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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