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An Electrical-Type Indicating Fuel Flowmeter

Description: "An electrical-type meter has been developed for measuring mass rates of flow of gasoline or other nonconducting fluids. Its temperature dependence is small over a large range and it has no known vibrational or viscosity errors. The maximum temperature rise is less than 5 C. The rates of flow, measurable within 1% with the present instrument, are approximately 100 to 1,000 or more pounds of gasoline per hour when a potentiometer is used, or 100 to 300 pounds per hour when a deflection-type mete… more
Date: September 1939
Creator: Tozier, Robert E.
Partner: UNT Libraries Government Documents Department
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Preliminary Tests of Nose- and Side- Entrance Blower Cooling Systems for Radial Engines, Special Report

Description: "Two cowling systems intended to reduce the drag and improve the low-speed cooling characteristics of conventional radial engine cowlings were tested in model form to determine the practicability of the methods. One cowling included a blower mounted on the rear face of a large propeller spinner which drew cooling air in through side entrance ducts located behind the equivalent engine orifice plate. The air was passed through the equivalent engine orifice plate from rear to front and out throug… more
Date: July 1939
Creator: Biermann, David & Valentine, E. Floyd
Partner: UNT Libraries Government Documents Department
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Preliminary Tests of Blowers of Three Designs Operating in Conjunction with a Wing-Duct Cooling System for Radial Engines, Special Report

Description: "This paper is one of several dealing with methods intended to reduce the drag of present-day radial engine installations and improve the cooling at zero and low air speeds. The present paper describes model wind-tunnel tests of blowers of three designs tested in conjunction with a wing-nacelle combination. The principle of operation involved consists of drawing cooling air into ducts located in the wing root at the point of maximum slipstream velocity, passing the air through the engine baffle… more
Date: June 1939
Creator: Biermann, David & Valentine, E. Floyd
Partner: UNT Libraries Government Documents Department
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Experiments on the Recovery of Waste Heat in Cooling Ducts, Special Report

Description: Tests have been conducted in the N.A.C.A. full-scale wind tunnel to investigate the partial recovery of the heat energy which is apparently wasted in the cooling of aircraft engines. The results indicate that if the radiator is located in an expanded duct, a part of the energy lost in cooling is recovered; however, the energy recovery is not of practical importance up to airplane speeds of 400 miles per hour. Throttling of the duct flow occurs with heated radiators and must be considered in des… more
Date: May 1939
Creator: Silverstein, Abe
Partner: UNT Libraries Government Documents Department
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Tests of Several Model Nacelle-Propeller Arrangements in Front of a Wing

Description: "An investigation was conducted in the N.A.C.A. 20-foot wind tunnel to determine the drag, the propulsive and net efficiencies, and the cooling characteristics of several scale-model arrangements of air-cooled radial-engine nacelles and present-day propellers in front of an 18- percent-thick, 5- by 15-foot airfoil. This report deals with an investigation of wing-nacelle arrangements simulating the geometric proportions of airplanes in the 40,000- to 70,000- pound weight classification and havin… more
Date: September 1939
Creator: McHugh, James G.
Partner: UNT Libraries Government Documents Department
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Pressure Distribution on the Fuselage of a Midwing Airplane Model at High Speeds

Description: "The pressure distribution on the fuselage of a midwing airplane model was measured in the NACA 8-foot high speed wind tunnel at speeds from 140 to 440 miles per hour for lift coefficients ranging from -0.2 to 1.0. The primary purpose of the tests was to provide data showing the air pressures on various parts of the fuselage for use in structural design. The data may also be used for the design of scoops and vents. The results show that the highest negative pressures occurred near the wing and … more
Date: November 1939
Creator: Delano, James B.
Partner: UNT Libraries Government Documents Department
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An Investigation of the Prevention of Ice on the Airplane Windshield

Description: "An investigation has been completed on several methods for the prevention and removal of ice on an airplane windshield. Tests were made on the use of electric heating, hot-air heating, and an alcohol-dispensing, rotating wiper blade. The results showed that vision through the airplane windshield could be maintained during severe icing conditions by the use of heat" (p. 1).
Date: November 1939
Creator: Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department
open access

Drag and Propulsive Characteristics of Air-Cooled Engine-Nacelle Installations for Large Airplanes, Special Report

Description: "An investigation is in progress in the NACA full-scale wind tunnel to determine the drag and propulsive efficiency of nacelle sizes. In contrast with the usual tests with a single nacelle, these tests were conducted with nacelle-propeller installations on a large model of a 4-engine airplane. Data are presented on the first part of the investigation, covering seven nacelle arrangements with nacelle diameters from 0.53 to 1.5 times the wing thickness" (p. 1).
Date: August 1939
Creator: Silverstein, Abe & Wilson, Herbert A., Jr.
Partner: UNT Libraries Government Documents Department
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Tests of Airfoils Designed to Delay the Compressibility Burble

Description: "Development of airfoil sections suitable for high-speed applications has generally been difficult because little was known of the flow phenomenon that occurs at high speeds. A definite critical speed has been found at which serious detrimental flow changes occur that lead to serious losses in lift and large increases in drag. This flow phenomenon, called the compressibility burble, was originally a propeller problem, but with the development of higher speed aircraft serious consideration must … more
Date: June 1939
Creator: Stack, John
Partner: UNT Libraries Government Documents Department
open access

Preliminary Model Tests of a Wing-Duct Cooling System for Radial Engines, Special Report

Description: "Wind-tunnel tests were conducted on a model wing-nacelle combination to determine the practicability of cooling radial engines by forcing the cooling air into wing-duct entrances located in the propeller slipstream, passing the air through the engine baffles from rear to front, and ejecting the air through an annular slot near the front of the nacelle. The drag of the cowlings tested was definitely less than for the conventional N.A.C.A. cowling, and the pressure available at low air speed cor… more
Date: February 1939
Creator: Biermann, David & Valentine, E. Floyd
Partner: UNT Libraries Government Documents Department
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Intercooler Design for Aircraft, Special Report

Description: "When an airplane is operating at high altitude, it is necessary to use a supercharger to maintain ground pressure at the carburetor inlet. This maintenance and high intake-manifold pressure tends to keep the power output of the engine at ground-level value. The air, being compressed by the supercharger, however, is heated by adiabatic compression and friction to a temperature that seriously affect the performance of the engine. It is thus necessary to use an intercooler to reduce the temperatu… more
Date: September 1939
Creator: Brevoort, M. J.; Joyner, U. T. & Leifer, M.
Partner: UNT Libraries Government Documents Department
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Engine Operation in Flight for Minimum Fuel Consumption

Description: "Engine and airplane performance data have been gathered from various sources and analyzed to determine indications of the most economical methods of flight operation from a consideration of fuel expenditure. The analysis includes the influence of such facts as fuel-air ratio, engine speed, engine knock, altitude, cylinder cooling, spark timing, and limits of cruising brake mean effective pressure. The results indicate that the cheapest power is obtained with approximately correct mixture at lo… more
Date: November 1939
Creator: Reuter, George
Partner: UNT Libraries Government Documents Department
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Tandem Air Propellers - 2

Description: "Tests of three-blade, adjustable-pitch counterrotating tandem model propellers, adjusted to absorb equal power at maximum efficiency of the combination, were made at Stanford University. The aerodynamic characteristics, for blade-angle settings of 15, 25, 35, 45, 55, and 65 degrees at 0.75R of the forward propeller and for diameters spacings of 8-1/2, 15 and 30% were compared with those of three-blade and six-blade propellers of the same blade form. It was found that, in order to realize the c… more
Date: October 1939
Creator: Lesley, E. P.
Partner: UNT Libraries Government Documents Department
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Investigation of an Electrically Heated Airplane Windshield for Ice Prevention, Special Report

Description: "A study was made at the National Advisory Committee for Aeronautics Laboratory of the operation of an electrically heated glass panel, which simulated a segment of an airplane windshield, to determine if ice formations, which usually result in the loss of visibility, could be prevented. Tests were made in the 7- by 3-foot ice tunnel, and in flight, under artificially created ice-forming conditions. Ice was prevented from forming on the windshield model in the tunnel by 1.25 watts of power per … more
Date: March 1939
Creator: Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department
open access

Full-Scale Wind-Tunnel Investigation of Wing-Cooling Ducts Effects of Propeller Slipstream, Special Report

Description: Report presenting an investigation of finite span wing-cooling ducts that has been extended to include a study of the effects of slipstream on the duct characteristics. The results indicated that the propeller slipstream is effective in generating a flow of air through the ducts of the ground condition.
Date: March 1939
Creator: Nickle, F. R. & Freeman, Arthur B.
Partner: UNT Libraries Government Documents Department
open access

High-Speed Tests of Radial-Engine Cowlings

Description: The drag characteristics of eight radial-engine cowlings have been determined over a wide speed range in the N.A.C.A. 8-foot high-speed wind tunnel. The pressure distribution over all cowlings was measured, to and above the speed of the compressibility burble, as an aid in interpreting the force tests. One-fifth-scale models of radial-engine cowlings on a wing-nacelle combination mere used in the tests.
Date: April 1939
Creator: Robinson, Russell G. & Becker, John V.
Partner: UNT Libraries Government Documents Department
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Tests of related forward-camber airfoils in the variable-density wind tunnel

Description: "A recent investigation of numerous related airfoils indicated that positions of camber forward of the usual location resulted in an increase of the maximum lift. As an extension of this investigation, a series of forward-camber airfoils has been developed, the members of which show airfoil characteristics superior to those of the airfoils previously investigated. The primary object of this report is to present fully corrected results for airfoils in the useful range of shapes. With the data th… more
Date: 1939
Creator: Jacobs, Eastman N.; Pinkerton, Robert M. & Greenberg, Harry
Partner: UNT Libraries Government Documents Department
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Airfoil section characteristics as affected by variations of the Reynolds number

Description: Report presents the results of an investigation of a systematically chosen representative group of related airfoils conducted in the NACA variable-density wind tunnel over a wide range of Reynolds number extending well into the flight range. The tests were made to provide information from which the variations of airfoil section characteristics with changes in the Reynolds number could be inferred and methods of allowing for these variations in practice could be determined. This work is one phas… more
Date: 1939
Creator: Jacobs, Eastman N. & Sherman, Albert
Partner: UNT Libraries Government Documents Department
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Tests of NACA 0009, 0012, and 0018 Airfoils in the Full-Scale Tunnel

Description: "An investigation was conducted in the NACA full-scale wind tunnel to determine the aerodynamic characteristics of the NACA 0009, 0012, and 0018 airfoils, with the ultimate purpose of providing data to be used as a basis for comparison with other wind-tunnel data, mainly in the study of scale and turbulence effects. Three symmetrical 6 by 36-foot rectangular airfoils were used. The Reynolds number range for minimum drag was form 1,800,000 to 7,000,000 and for maximum lift, from 1,700,000 to 4,5… more
Date: 1939
Creator: Goett, Harry J. & Bullivant, W. Kenneth
Partner: UNT Libraries Government Documents Department
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The aerodynamic characteristics of six full-scale propellers having different airfoil sections

Description: From Summary: "Wind-tunnel tests are reported of six 3-blade 10-foot propellers operated in front of a liquid-cooled engine nacelle. The propellers were identical except for blade airfoil sections, which were: Clark y, R.A.F. 6, NACA 4400, NACA 2400-34, NACA 2rsub200, and NACA 6400. The range of blade angles investigated extended for 15 degrees to 40 degrees for all propellers except the Clark y, for which it extended to 45 degrees. The results showed that the range in maximum efficiency betwee… more
Date: 1939
Creator: Biermann, David & Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department
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Calculation of the Induced Efficiency of Heavily Loaded Propellers Having Infinite Number of Blades

Description: Report presenting an approximate method of computing the induced efficiency of heavily loaded propellers in suitable form for extension to finite number of blades and a comparison of results obtained using the method with the data of the Betz-Helmbold theory for heavily loaded propellers.
Date: January 1939
Creator: Lösch, F.; Kramer, K. N.; Bock, G. & Nikodemus, R.
Partner: UNT Libraries Government Documents Department
open access

Selected Russian Papers on Geochemical Prospecting for Ores

Description: A selection of Russian papers on the geochemical prospecting for ores
Date: 1939/1946
Creator: Sokoloff, V. P.; Hawkes, H. E. (Herbert Edwin), 1912-1996; Ratsbaum, E. A.; Sergeev, Evgeniĭ (Evgeniĭ Aleksandrovich); Sergeev, Evgeniĭ (Evgeniĭ Aleksandrovich); Sergeev, Evgeniĭ (Evgeniĭ Aleksandrovich) et al.
Partner: UNT Libraries Government Documents Department
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