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The effect of turbulence on the drag of flat plates

Description: "In determining the effect of turbulence on the forces exerted on bodies in the air stream of a wind tunnel, it is commonly assumed that the indications of the standard Pitot-static tube used to determine the air speed are not dependent on the turbulence. To investigate the truth of this assumption, the drag of a normally exposed flat plate, the difference in pressure between the front and rear of a thin circular disk, the rate of rotation of a vane anemometer, and the pressure developed by a s… more
Date: June 22, 1935
Creator: Schubauer, G. B. & Dryden, H. L.
Partner: UNT Libraries Government Documents Department
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The Effect of Water Vapor on Flame Velocity in Equivalent Carbon Monoxide and Oxygen Mixtures

Description: This report presents the results of an investigation to study the effect of water vapor upon the spatial speed of flame in equivalent mixtures of carbon monoxide and oxygen at various total pressures from 100 to 780 mm.hg. These results show that, within this pressure range, an increase in flame speed is produced by increasing the mole fraction of water vapor at least as far as saturation at 25 degrees c., and that the rate of this increase is greater the higher the pressure. It is evident that… more
Date: January 10, 1935
Creator: Fiock, Ernest F. & King, H. Kendall
Partner: UNT Libraries Government Documents Department
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Effects of air-fuel spray and flame formation in a compression-ignition engine

Description: "High-speed motion pictures were taken at the rate of 2,500 frames per second of the fuel spray and flame formation in the combustion chamber of the NACA combustion apparatus. The compression ratio was 13.2 and the speed 1,500 revolutions per minute. An optical indicator was used to record the time-pressure relationship in the combustion chamber. The air-fuel ratio was varied from 10.4 to 365. The results showed that as the air-fuel ratio was increased definite stratification of the charge occu… more
Date: August 26, 1935
Creator: Rothrock, A. M. & Waldron, C. D.
Partner: UNT Libraries Government Documents Department
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Engineering Factors in the Ventilation of Metal Mines

Description: From Introduction Purpose and Scope of Report: "In the belief that the quickest and cheapest method of obtaining effective ventilation of metal mines with regard to air conditions that promote efficiency, health, and safety is through more general application of the engineering factors involved rather than by trial and error and this method of attacking ventilation problems will be facilitated by a simple, concise statement of these factors and the methods of using them, an attempt is made in t… more
Date: 1935
Creator: McElroy, G. E.
Partner: UNT Libraries Government Documents Department
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Experiments with Suction-Type Wings

Description: The present report collects the investigations of the past years which, while not as yet intended for use in construction, show different possibilities for the building of a suction-type wing and at the same time present some basic explanations concerning the problem of suction. Experiments and results with a thick wing profile are detailed as well as boundary layer removal by suction and sink action. Experiments with flap profiles are also included.
Date: August 1935
Creator: Schrenk, O.
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of the Spinning of the F4B-2 Biplane with Various Loads and Tail Surfaces

Description: "A flight investigation of the spinning of the F4B-2 single-seat fighter airplane was made for the purpose of finding modifications that would eliminate dangerous spin tendencies exhibited by this type of airplane in service. The effects on steady spins and on recoveries of changing the loading, enlarging the fin areas, changing the elevator plan form, and raising the horizontal surfaces, were determined" (p. 413).
Date: February 12, 1935
Creator: Scudder, N. F. & Seidman, Oscar
Partner: UNT Libraries Government Documents Department
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Flight tests of a balanced split flap with particular reference to rapid operation

Description: The flight path of a small parasol monoplane equipped with a special type of balanced split flap was determined for a series of glides during which the time taken to deflect or retract the flap was varied from 1 to 15 seconds in order to study the effect of the time taken to complete a flap movement on the motion of an airplane between the start of a flap movement and the attainment of steady flight with the new flap setting. For flap movements accompanied by a change of lift characteristics, a… more
Date: December 1935
Creator: Soulé, H. A.
Partner: UNT Libraries Government Documents Department
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Full-scale force and pressure-distribution tests on a tapered U.S.A. 45 airfoil

Description: This report presents the results of force and pressure-distribution tests on a 2:1 tapered USA 45 airfoil as determined in the full-scale wind tunnel. The airfoil has a constant-chord center section and rounded tips and is tapered in thickness from 18 percent at the root to 9 percent at the tip. Force tests were made throughout a Reynolds Number range of approximately 2,000,000 to 8,000,000 providing data on the scale effect in addition to the conventional characteristics. Pressure-distribution… more
Date: March 1935
Creator: Parsons, John F.
Partner: UNT Libraries Government Documents Department
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Further Studies of Flame Movement and Pressure Development in an Engine Cylinder

Description: This report describes an investigation using a stroboscopic apparatus for observing flame movement through a large number of small windows distributed over the head of a spark-ignition engine in following flame spread with combustion chambers of different shapes at two engine speed and for a variety of spark-plug locations including single and twin ignition. The principal factors influencing flame movement in the engine are discussed, and the lack of reliable information regarding their separat… more
Date: September 1935
Creator: Marvin, Charles F., Jr.; Wharton, Armistead & Roeder, Carl H.
Partner: UNT Libraries Government Documents Department
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A general tank test of NACA model 11-C flying-boat hull, including the effect of changing the plan form of the step

Description: The results of a general tank test model 11-C, a conventional pointed afterbody type of flying-boat hull, are given in tables and curves. These results are compared with the results of tests on model 11-A, from which model 11-C was derived, and it is found that the resistance of model 11-C is somewhat greater. The effect of changing the plan form of the step on model 11-C is shown from the results of tests made with three swallow-tail and three pointed steps formed by altering the original step… more
Date: August 1935
Creator: Dawson, John R.
Partner: UNT Libraries Government Documents Department
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Geology of Big Horn County and the Crow Indian Reservation, Montana: with Special Reference to the Water, Coal, Oil and Gas Resources

Description: From introduction: This report contains information concerning the geology of Big Horn County and the Crow Indian Reservation and their resources in ground water, coal, oil, and gas. These facts were collected in the course of studies for about a dozen field projects, which ranged in character from reconnaissance studies of large areas to very detailed mapping of certain tracts to show the occurrence of oil and gas. Consequently, the information at hand, either as to the geology or the resource… more
Date: 1935
Creator: Thom, W. T., Jr.; Hall, George Martin; Wegemann, Carroll H. & Moulton, G. F.
Partner: UNT Libraries Government Documents Department
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Geology of the Santa Rita Mining Area, New Mexico

Description: From abstract: The Santa Rita mining area (pl. 1), covering 35 square miles of semiarid mountainous land, lies within the Silver City 30-minute quadrangle, Grant County, N. Mex., and includes the most productive part of the Central or Hanover mining district. Ore was produced in this district as early as 1804 and production continued intermittently for a century before the developments were undertaken that led to large-scale copper mining, which began in 1912. The output of zinc, lead, and iron… more
Date: 1935
Creator: Spencer, Arthur C. & Paige, Sidney
Partner: UNT Libraries Government Documents Department
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Geology of the Tonsina District, Alaska

Description: From introduction: The purpose of this paper is to describe the geology and mineral resources of a part of the Copper River Basin between the Richardson Highway and the valley of the Klutina River, together with small areas east of the highway and west of the river. For convenience in reference this area is called the Tonsina district, as the Tonsina River and Tonsina Lake are conspicuous local geographic features, and the Tonsina Road House, on the highway at the crossing of the river, is one … more
Date: 1935
Creator: Moffit, Fred H.
Partner: UNT Libraries Government Documents Department
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Glider Development in Germany: A Technical Survey of Progress in Design in Germany Since 1922

Description: This report is a recounting of glider development beginning with the "Vampyr" on up to the present day. The primary purpose is to determine what the fundamental features of the glider are and what the course of its development has been during the thirteen years of activity in motorless flight.
Date: November 1935
Creator: Shenstone, B. S. & Scott-Hall, S.
Partner: UNT Libraries Government Documents Department
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Gliding in Convection Currents

Description: "A survey of the possibilities of gliding in convection currents reveals that heretofore only the most simple kind of ascending convection currents, that is, the "thermic" of insolation, has been utilized to any extent. With the increasing experience in gliding, the utilization of the peculiar nature of the "wind thermic" and increased glider speed promises further advances. Evening, ocean, and height "thermic" are still in the exploration stage, and therefore not amenable to survey in their ef… more
Date: January 1935
Creator: Georgii, W.
Partner: UNT Libraries Government Documents Department
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The Heat Transfer of Cooling Fins on Moving Air

Description: The present report is a comparison of the experimentally defined temperature and heat output of cooling fins in the air stream with theory. The agreement is close on the basis of a mean coefficient of heat transfer with respect to the total surface. A relationship is established between the mean coefficient of heat transfer, the dimensions of the fin arrangement, and the air velocity.
Date: January 1935
Creator: Doetsch, Hans
Partner: UNT Libraries Government Documents Department
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Hydrodynamic Tests of Models of Seaplane Floats

Description: "This report contains the results of tank tests carried out at free trim on seventeen hulls and floats of various types. The data as to the weight on water, trim, and relative resistance for each model are plotted nondimensionally and are referenced both to the total weight and to the weight on water. Despite the fact that the experiments were not made systematically, a study of the models and of the test data permits nevertheless some general deductions regarding the forms of floats and their … more
Date: May 1935
Creator: Eula, Antonio
Partner: UNT Libraries Government Documents Department
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Hydrogen as an auxiliary fuel in compression-ignition engines

Description: From Summary: "An investigation was made to determine whether a sufficient amount of hydrogen could be efficiently burned in a compression-ignition engine to compensate for the increase of lift of an airship due to the consumption of the fuel oil. The performance of a single-cylinder four-stroke-cycle compression-ignition engine operating on fuel oil alone was compared with its performance when various quantities of hydrogen were inducted with the inlet air. Engine-performance data, indicator c… more
Date: April 15, 1935
Creator: Gerrish, Harold C. & Foster, Hampton H.
Partner: UNT Libraries Government Documents Department
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Ice Prevention on Aircraft by Means of Impregnated Leather Covers, Special Report

Description: "The National Advisory Committee for Aeronautics is testing the effectiveness of a method to prevent the formation of ice on airplanes. The system makes use of a leather cover that is attached to the leading edge of the wing. A small tube, attached to the inner surface of the leather, distributes to the leading edge a solution that permeates throughout the leather and inhibits the formation of ice on the surface. About 25 pounds of the liquid per hour would be sufficient to prevent ice from for… more
Date: August 1935
Creator: Clay, William C.
Partner: UNT Libraries Government Documents Department
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The Initial Torsional Stiffness of Shells With Interior Webs

Description: "A method of calculating the stresses and torsional stiffness of thin shells with interior webs is summarized. Comparisons between experimental and calculated results are given for 3 duralumin beams, 5 stainless steel beams and 2 duralumin wings. It is concluded that if the theoretical stiffness is multiplied by a correction factor of 0.9, experimental values may be expected to check calculated values within about 10 percent" (p. 1).
Date: September 1935
Creator: Kuhn, Paul
Partner: UNT Libraries Government Documents Department
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The Interdependence of Profile Drag and Lift With Joukowski Type and Related Airfoils

Description: "On the basis of a systematic investigation of Gottingen wind-tunnel data on Joukowski type and related airfoils, it is shown in what manner the profile drag coefficient is dependent on the lift coefficient. The individual factors for the construction of the profile drag polars are given. They afford a more accurate calculation of the performance coefficients of airplane designs than otherwise attainable with the conventional assumption of constant drag coefficient" (p. 1).
Date: March 1935
Creator: Muttray, H.
Partner: UNT Libraries Government Documents Department
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Interference of wing and fuselage from tests of 209 combinations in the NACA variable-density tunnel

Description: This report presents the results of tests of 209 simple wing-fuselage combinations made in the NACA variable-density wind tunnel to provide information regarding the effects of aerodynamic interference between wings and fuselages at a large value of Reynolds number.
Date: March 8, 1935
Creator: Jacobs, Eastman N. & Ward, Kenneth E.
Partner: UNT Libraries Government Documents Department
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Investigation of Full-Scale Split Trailing-Edge Wing Flaps With Various Chords and Hinge Locations

Description: This report gives the results of an investigation conducted in the NACA full-scale wind tunnel on a small parasol monoplane equipped with three different split trailing-edge wing flaps. The object of the investigation was to determine and correlate data on the characteristics of the airplane and flaps as affected by variation in flap chord, flap deflection, and flap location along the wing chord. The results give the lift, the drag, and the pitching moment characteristics of the airplane, and t… more
Date: May 10, 1935
Creator: Wallace, Rudolf
Partner: UNT Libraries Government Documents Department
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