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Investigations Relating to the Extension of Laminar Flow by Means of Boundary-Layer Suction Through Slots

Description: Note presenting experimental investigations of boundary-layer suction through slots as a means of increasing the extent of laminar flow on airfoil sections. The results show that, with the use of suitable slots, substantial increases in the extent of laminar flow can be achieved by boundary-layer control with only a small expenditure of power. Results regarding slot geometry and arrangement, suction slots in an unfavorable pressure gradient, suction slots in a favorable pressure gradient, and d… more
Date: October 1949
Creator: Loftin, Laurence K., Jr. & Burrows, Dale L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Icing Characteristics of Typical Light Airplane Engine Induction Systems

Description: "The icing characteristics of two typical light-airplane engine induction systems were investigated using the carburetors and manifolds of engines in the horsepower ranges from 65 to 85 and 165 to 185. The smaller system consisted of a float-type carburetor with an unheated manifold and the larger system consisted of a single-barrel pressure-type carburetor with an oil-jacketed manifold. Carburetor-air temperature and humidity limits of visible and serious Icing were determined for various engi… more
Date: February 1949
Creator: Coles, Willard D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of Icing of an Engine Cooling-Fan Installation

Description: Note presenting an investigation of the icing characteristics and means of ice protection of a typical radial-engine cooling-fan installation. The icing of the unprotected cooling-fan installation was found to present a serious operational problem. Results regarding icing, steam heat de-icing, alcohol de-icing, and electrical heat de-icing are provided.
Date: April 1947
Creator: Lewis, James P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Aerodynamic and Icing Characteristics of Recessed Fuel-Vent Configurations

Description: From Summary: "An investigation has been conducted in the NACA Cleveland icing research tunnel to determine the aerodynamic and icing characteristics of several recessed fuel-vent configurations. The vents were investigated aerodynamically to obtain vent-tube pressures and pressure distributions on the ramp surface as functions of tunnel-air velocity and angle of attack. Icing investigations were made to determine the vent-tube pressure losses for several icing conditions at tunnel-air velociti… more
Date: March 1949
Creator: Ruggeri, Robert S.; von Glahn, Uwe H. & Rollin, Vern G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of Ice Formations on Airplane Performance in Level Cruising Flight

Description: "A flight investigation in natural icing conditions was conducted by the NACA to determine the effect of ice accretion on airplane performance. The maximum loss in propeller efficiency encountered due to ice formation on the propeller blades was 19 percent. During 87 percent of the propeller icing encounters, losses of 10 percent or less were observed" (p. 1).
Date: May 1948
Creator: Preston, G. Merritt & Blackman, Calvin C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of the Thermal Performance of Air Heated Propeller

Description: Note presenting the thermal performance of an air-heated propeller, installed on a test airplane, as evaluated by observations of the ice-prevention properties of the propeller during flight in natural icing conditions and by the collection of thermal data on the propeller during flight in clear air and in clouds at temperatures above freezing. The results indicated that the air-heated-propeller installation tested would offer little or no protection to the leading-edge regions of the propeller… more
Date: April 1947
Creator: Darsow, John F. & Selna, James
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Icing and De-Icing of a Propeller with Internal Electric Blade Heaters

Description: "An investigation has been made in the NACA Cleveland icing research tunnel to determine the de-icing effectiveness of an experimental configuration of an Internal electric propeller-blade heater. Two atmospheric Icing conditions and two propeller operating conditions were Investigated in experiments with unheated blades and with heat applied to the blades both continuously and cyclically. Data are presented to show the effect of propeller speed, ambient air temperature and liquid-water concent… more
Date: August 1948
Creator: Lewis, James P. & Stevens, Howard C., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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De-Icing Effectiveness of External Electric Heaters for Propeller Blades

Description: Note presenting an investigation in the icing research tunnel to determine the icing protection provided by external rubber-clad blade heaters at several icing, heating, and propeller operating conditions. Data are presented to show the effect of propeller speed, ambient-air temperature, liquid-water concentration, heating-power density, duration of heating, and total cycle times on the power requirements and de-icing performance of the blade heaters.
Date: February 1948
Creator: Lewis, James P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Effectiveness of Air-Heating a Hollow Steel Propeller for Protection Against Icing 1: Unpartitioned Blades

Description: From Summary: "An investigation to determine the effectiveness of icing protection afforded by air-heating hollow steel unpartitioned propeller blades has been conducted In the NACA Cleveland icing research tunnel. The propeller used was a production model modified with blade shank and tip openings to permit internal passage of heated air. Blade-surface and heated-air temperatures were obtained and photographic observations of Ice formations were made with variations In icing intensity and heat… more
Date: May 1948
Creator: Mulholland, Donald R. & Perkins, Porter J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Effectiveness of Air-Heating a Hollow Steel Propeller for Protection Against Icing. 2: 50% Impartitioned Blades

Description: From Summary: "The icing protection afforded an internal air-heated propeller blade by radial partitioning at 50-percent chord to confine the heated air to the forward half of the blade was determined in the NACA Cleveland icing research tunnel. A modified production-model hollow steel propeller, was used for the investigation. Temperatures of the blade surfaces for several heating rates were measured under various tunnel icing conditions. Photographic observations of ice formations on blade su… more
Date: May 1948
Creator: Perkins, Porter J. & Mulholland, Donald R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Effectiveness of Air-Heating a Hollow Steel Propeller for Protection Against Icing. 3: 25% Partitioned Blades

Description: From Summary: "The icing protection obtained from an internally air-heated propeller blade partitioned to confine the heated air forward of 25-percent chord was investigated in the NACA Cleveland icing research tunnel. A production-model hollow steel propeller was modified with an Internal radial partition at 25-percent chord and with shank and tip openings to admit and exhaust the heated air. Temperatures were measured on the blade surfaces and in the heated-air system during tunnel icing cond… more
Date: May 1948
Creator: Mulholland, Donald R. & Perkins, Porter J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Method for Estimating Heat Requirements for Ice Prevention Gas Heated Hollow Propeller Blades

Description: Report presenting a method for determining the temperature and flow of heated gas necessary for ice prevention of hollow propeller blades in flight and icing conditions. A variety of conditions are taken into consideration and suggested simplifications and short methods are provided in order to not overcomplicate the design modifications.
Date: December 1947
Creator: Gray, V. H. & Campbell, R. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Suction-Slot Shapes for Controlling a Turbulent Boundary Layer

Description: Note presenting tests of three types of boundary-layer-control suction slots in a two-dimensional diffuser to investigate design criterions and to evaluate the practical minimum total-pressure losses. Testing occurred at a velocity of about 100 feet per second with a boundary layer with a displacement thickness of 0.85 inch and a shape parameter of about 1.8.
Date: June 1947
Creator: Pierpont, P. Kenneth
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Calculation of the Heat Required for Wing Thermal Ice Prevention in Specified Icing Conditions

Description: Note presenting a verification of previously derived equations for calculating the rate of heat transfer from airfoils in icing conditions, which have come about as a result of an investigation of the meteorological conditions conducive to the formation of ice on aircraft and a study of the process of airfoil thermal ice prevention. The results indicated that knowledge of these components has increased to a point where the design of heated wings on a fundamental, wet-air basis can now be undert… more
Date: December 1947
Creator: Neel, Carr B., Jr.; Bergrun, Norman R.; Jukoff, David & Schlaff, Bernard A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Method for Numerically Calculating the Area and Distribution of Water Impingement on the Leading Edge of an Airfoil in a Cloud

Description: Note presenting a method for determining, by step-by-step integration, the trajectories of water drops around any body in two-dimensional flow for which the streamline velocity components are known or can be computed. The equations are presented in general form and then, to illustrate the procedure, water-drop trajectories are calculated about a 12-percent-thick symmetrical Joukowski profile chosen to simulate an NACA 0012 section. The method provides a means for the relatively rapid calculatio… more
Date: August 1947
Creator: Bergrun, Norman R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of the Penetration of an Air Jet Directed Perpendicularly to an Air Stream

Description: Note presenting an experimental investigation to determine the penetration of a circular air jet directed perpendicularly to an air stream as a function of jet density, jet velocity, air-stream density, air-stream velocity, jet diameter, and distance downstream from the jet. The penetration was determined for nearly constant values of air-stream density at two tunnel velocities, four jet diameters, four positions downstream of the jet, and for a large range of jet velocities and densities.
Date: June 1948
Creator: Callaghan, Edmund E. & Ruggeri, Robert S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Flow Coefficient of Circular, Square, and Elliptical Orifices at High Pressure Ratios

Description: Note presenting an experimental investigation conducted to determine the orifice coefficient of a jet directed perpendicularly to an air stream as a function of pressure ratio and jet Reynolds number for circular, square, and elliptical orifices. The effect of air-stream velocity on the jet flow was also determined for three tunnel-air velocities. Results regarding jets discharging into still air and effect of tunnel-air velocity on jet flow.
Date: September 1949
Creator: Callaghan, Edmund E. & Bowden, Dean T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Simple Method of Estimating the Subsonic Lift and Damping in Roll of Sweptback Wings

Description: "A method of modifying existing correction factors of lifting-surface theory to account approximately for the effects of sweep was derived, and these factors were applied to existing lifting-line theories for the lift and damping in roll of swept wings. Despite the simplicity of the resulting formulas the agreement with experimental data for low speeds is very good. The equation for lift is expressed entirely in terms of the geometric characteristics of the wing and the section-lift-curve; the … more
Date: April 1949
Creator: Polhamus, Edward C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Icing Properties of Noncyclonic Winter Stratus Clouds

Description: Note presenting measurements of the vertical distribution of liquid water concentration and drop size in winter stratus clouds in the absence of significant cyclonic or frontal activity. The observations indicate that the clouds are formed by turbulent mixing of the lower layers of the atmosphere, resulting in a region of constant specific humidity and adiabatic lapse rates. Calculations based on the observations were used to construct a graph that gives the liquid water concentration in terms … more
Date: September 1947
Creator: Lewis, William
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Observations of Icing Conditions Encountered in Flight During 1948

Description: Note presenting meteorological data from flight observations in icing conditions during the first 5 months of 1948. A total of 335 measurements of liquid-water content and mean-effective drop diameter were obtained by the multicylinder method in the course of 40 flights in icing conditions covering most of the northern United States. Information regarding the discontinuous character of icing clouds, variation of average liquid-water content with extent of icing conditions, and variation of drop… more
Date: June 1949
Creator: Lewis, William & Hoecker, Walter H., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests on Stiffened Circular Cylinders

Description: "Compressive tests were made of two series of stiffened circular cylindrical shells under axial load. All the shells were 16 inches in diameter by 24 inches in length and were made of aluminum-alloy sheet curved to the proper radius and welded with one longitudinal weld. The ratios of diameter to thickness of shell wall in the two series of specimens were 258 and 572" (p. 1).
Date: March 1941
Creator: Holt, Marshall
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests of Round and Flat Spoilers on a Tapered Wing in the NACA 19-Foot Pressure Wind Tunnel

Description: "Several arrangements of round and flat spanwise spoilers attached to the upper surface of a tapered wing were tested in the NACA 19-foot pressure wind tunnel to determine the most effective type, location, and size of spoiler necessary to reduce greatly the lift on the wings of large flying boats when moored. The effect of the various spoilers on the lift, the drag, and the pitching-moment characteristics of the tapered wing was measured over a range of angles of attack from zero to maximum li… more
Date: March 1941
Creator: Wenzinger, Carl J. & Bowen, John D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests of a gust-alleviating wing in the gust tunnel

Description: "Tests were made in the NACA gust tunnel to determine the effectiveness of a torsionally flexible wing with the torsion axis ahead of the locus of the section aerodynamic centers in reducing airplane accelerations due to atmospheric gusts. For three gust shapes, a series of flights was made with the airplane model equipped with either a torsionally flexible or a rigid wing. The results indicated that the torsionally flexible wing reduced the maximum acceleration increment 5 percent for the shar… more
Date: April 1941
Creator: Shufflebarger, C. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Experimental and Theoretical Studies of Area Suction for the Control of the Laminar Boundary Layer on a Porous Bronze NACA 64A010 Airfoil

Description: Note presenting a low-turbulence wind tunnel investigation of an NACA 64A010 airfoil with a porous surface of sintered bronze to determine the reduction in section drag coefficient that might be obtained at large Reynolds numbers by use of suction to produce continuous inflow through the surface of the model. Results regarding the uncompartmented model, compartmented model, observations on stability of laminar boundary layer, and theoretical calculations are provided.
Date: July 1949
Creator: Burrows, Dale L.; Braslow, Albert L. & Terervin, Neal
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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