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Basic Requirements of Fuel-Injection Nozzles for Quiescent Combustion Chambers

Description: This report presents test results obtained during an investigation of the performance of a single-cylinder, high-speed, compression-ignition test engine when using multiple-orifice fuel-injection valve nozzles in which the number and the direction of the orifices were varied independently.
Date: June 1931
Creator: Spanogle, J. A. & Foster, H. H.
Partner: UNT Libraries Government Documents Department
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The Behavior of Conventional Airplanes in Situations Thought to Lead to Most Crashes

Description: Simple flight tests were made on ten conventional airplanes for the purpose of determining their action in two situations, which are generally thought to precede and lead to a large proportion of airplane crashes. These situations are when in an attempt to stretch the glide in a forced landing, the airplane is stalled, and when while taking off, particularly if taking off steeply, the engine fails at a low altitude.
Date: February 1931
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
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The Behavior of Thin-Will Monocoque Cylinders Under Torsional Vibration

Description: "Curves of forced frequency against amplitude are presented for the conditions where the forced frequency is both increased and decreased into the resonant range. On the basis of these curves it is shown that the practical resonance frequency is the point where wrinkling first occurs and that the resonance frequency will be subject to considerable travel once permanent wrinkles appear in the vibrating shell. The decreasing mode of striking resonance is found to be by far the most destructive co… more
Date: August 1937
Creator: Pekelsma, Robert E.
Partner: UNT Libraries Government Documents Department
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Bending Stresses Due to Torsion in Cantilever Box Beams

Description: "The paper beings with a brief discussion on the origin of the bending stresses in cantilever box beams under torsion. A critical survey of existing theory is followed by a summary of design formulas; this summary is based on the most complete solution published but omits all refinements considered unnecessary at the present state of development. Strain-gage tests made by NACA to obtained some experimental verification of the formulas are described next. Finally, the formulas are applied to a s… more
Date: June 1935
Creator: Kuhn, Paul
Partner: UNT Libraries Government Documents Department
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Bending Tests of Circular Cylinders of Corrugated Aluminum-Alloy Sheet

Description: "Bending tests were made of two circular cylinders of corrugated aluminum-alloy sheet. In each test failure occurred by bending of the corrugations in a plane normal to the skin. It was found, after analysis of the effect of short end bays, that the computed stress on the extreme fiber of a corrugated cylinder is in excess of that for a flat panel of the same basic pattern and panel length tested as a pin-ended column. It is concluded that this increased strength was due to the effects of curva… more
Date: March 1937
Creator: Niles, Alfred S.; Buckwalter, John C. & Reed, Warren D.
Partner: UNT Libraries Government Documents Department
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Boosted Performance of a Compression-Ignition Engine With a Displaced Piston

Description: From Summary: "Performance tests were made using a rectangular displacer arranged so that the combustion air was forced through equal passages at either end of the displacer into the vertical-disk combustion chamber of a single-cylinder, four-stroke-cycle compression-ignition test engine. After making tests to determine optimum displacer height, shape, and fuel-spray arrangement, engine-performance tests were made at 1,500 and 2,000 r.p.m. for a range of boost pressures from 0 to 20 inches of m… more
Date: May 1936
Creator: Moore, Charles S. & Foster, Hampton H.
Partner: UNT Libraries Government Documents Department
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The Calculated Effect of Trailing-Edge Flaps on the Take-Off of Flying Boats

Description: "The results of take-off calculations are given for an application of simple trailing-edge flaps to two hypothetical flying boats, one having medium wing and power loading and consequently considerable excess of thrust over total resistance during the take-off run, the other having high wing and power loading and a very low excess thrust. For these seaplanes the effect of downward flap settings was: (1) to increase the total resistance below the stalling speed, (2) to decrease the get-away spee… more
Date: November 1934
Creator: Parkinson, J. B. & Bell, J. W.
Partner: UNT Libraries Government Documents Department
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Calculated Effect of Various Types of Flap on Take-Off Over Obstacles

Description: "In order to determine whether or not flaps could be expected to have any beneficial effect on take-off performance, the distances required to take off and climb to an altitude of 50 feet were calculated for hypothetical airplanes, corresponding to relatively high-speed types and equipped with several types of flap. The types considered are the Fowler wing, the Hall wing, the split flap, the balanced split flap, the plain flap, and the external-airfoil flap. The results indicate that substantia… more
Date: May 1936
Creator: Wetmore, J. W.
Partner: UNT Libraries Government Documents Department
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Calculations of the Effect of Wing Twist on the Air Forces Acting on a Monoplane Wing

Description: "A method is presented for calculating the aerodynamic forces on a moncylane wing, taking into account the elastic twisting of the wing due to these forces. The lift distribution along the span is calculated by the formulas of Amstutz as a function of the geometrical characteristics of the wing and of the twist at stations 60 and 90 percent of the semispan. The twist for a given lift distribution is calculated by means of influence lines" (p. 1).
Date: March 1935
Creator: Dätwyler, G.
Partner: UNT Libraries Government Documents Department
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Calibration and lag of a Friez type cup anemometer

Description: "Tests on a Friez type cup anemometer have been made in the variable density wind tunnel of the Langley Memorial Aeronautical Laboratory to calibrate the instrument and to determine its suitability for velocity measurements of wind gusts. The instrument was calibrated against a Pitot-static tube placed directly above the anemometer at air densities corresponding to sea level, and to an altitude of approximately 6000 feet. Air-speed acceleration tests were made to determine the lag in the instru… more
Date: June 1930
Creator: Pinkerton, Robert M.
Partner: UNT Libraries Government Documents Department
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Carbon-monoxide indicators for aircraft

Description: Several improvements that have been made on commercially available carbon-monoxide indicators to make them more suitable for aircraft use are described. These improvements include an automatic flow regulator, which permits the use of a simplified instrument on aircraft where a source of suction is available, and a more reliable alarm attachment. A field method for testing instruments on standard samples of carbon monoxide is described. Performance data and instructions in operation and maintena… more
Date: July 1936
Creator: Womack, S. H. J. & Peterson, J. B.
Partner: UNT Libraries Government Documents Department
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Characteristics of an airfoil as affected by fabric sag

Description: "This report presents the results of tests made at a high value of the Reynolds Number in the N.A.C.A. variable-density wind tunnel to determine the aerodynamic characteristics of an airfoil as affected by fabric sag. Tests were made of two Gottingen 387 airfoils, one having the usual smooth surface and the other having a surface modified to simulate two types of fabric sag. The results of these tests indicate that the usual sagging of the wind covering between ribs has a very small effect on t… more
Date: August 1932
Creator: Ward, Kenneth E.
Partner: UNT Libraries Government Documents Department
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Characteristics of Two Sharp-Nosed Airfoils Having Reduced Spinning Tendencies

Description: "According to Mr. L.D. Bell, of the Consolidated Aircraft Corporation, certain undesirable spinning characteristics of a commercial airplane were eliminated by the addition of a filler to the forward part of the wing to give it a sharp leading edge. To ascertain what aerodynamic effects result from such a change of section, two airfoils having sharp leading edges were tested in the variable-density wind tunnel. Both sections were derived by modifying the Gott. 398. The tests, which were made at… more
Date: April 1932
Creator: Jacobs, Eastman N.
Partner: UNT Libraries Government Documents Department
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The charging process in a high-speed, single-cylinder, four-stroke engine

Description: From Summary: "Experimental measurements and theoretical calculations were made on an aircraft-type, single cylinder engine, in order to determine the physical nature of the inlet process, especially at high piston speeds. The engine was run at speeds from 1,500 to 2,600 r.p.m. (mean piston speeds of 1,370 to 2,380 feet per minute). Measurements were made of the cylinder pressure during the inlet stroke and of the power output and volumetric efficiency. Measurements were also made, with the eng… more
Date: February 1939
Creator: Reynolds, Blake; Schecter, Harry & Taylor, E. S.
Partner: UNT Libraries Government Documents Department
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Charts expressing the time, velocity, and altitude relations for an airplane diving in a standard atmosphere

Description: In this report charts are given showing the relation between time, velocities, and altitude for airplanes having various terminal velocities diving in a standard atmosphere. The range of starting altitudes is from 8,000 to 32,000 feet, and the terminal velocities vary from 150 to 550 miles per hour. A comparison is made between an experimental case and the results obtained from the charts. Examples pointing out the use of the charts are included.
Date: April 1937
Creator: Pearson, H. A.
Partner: UNT Libraries Government Documents Department
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Charts for Calculating the Performance of Airplanes Having Constant-Speed Propellers

Description: "Charts are presented for determining the performance of airplanes having variable-pitch propellers, the pitch of which is assumed to be adjusted to maintain constant speed for all rates of flight. The charts are based on the general performance equations developed by Oswald in reference 1, and are used in a similar manner. Examples applying the charts to airplanes having both supercharged and unsupercharged engines are included" (p. 1).
Date: September 1936
Creator: White, Roland J. & Martin, Victor J.
Partner: UNT Libraries Government Documents Department
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Charts for determining the pitching moment of tapered wings with sweepback and twist

Description: From Summary: "This report presents a convenient method for calculating the pitching-moment characteristics of tapered wings with sweepback and twist. The method is based on the fact that the pitching-moment characteristics of a wing may be specified by giving the value of the pitching moment at zero lift and the location of the axis about which the axis is constant. Data for calculating these characteristics are presented by curves which apply to wings having a linear distribution of twist alo… more
Date: December 1933
Creator: Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
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Circular Motion of Bodies of Revolution

Description: The circular motion for airship-like bodies has thus far been calculated only for a prolate ellipsoid of revolution (reference 1, p.133 and reference 2). In this paper, however, the circular motion of elongated bodies of revolution more nearly resembling airships will be investigated. The results will give the effect of rotation on the pressure distribution and thus yield some information as to the stresses set up in an airship in circular flight.
Date: February 1936
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Circulation Measurements About the Tip of an Airfoil During Flight Through a Gust

Description: "Measurements were made of the circulation about the rectangular tip of a short-span airfoil passing through an artificial gust of known velocity gradient. A Clark Y airfoil of 30-centimeter chord was mounted on a whirling arm and moved at a velocity of 29 meters per second over a vertical gust with a velocity of nearly 7 meters per second. Flow angles were measured with a hot-wire apparatus" (p. 1).
Date: February 1939
Creator: Kuethe, Arnold M.
Partner: UNT Libraries Government Documents Department
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Combined Beam-Column Stresses of Aluminum-Alloy Channel Sections

Description: The results of a research program to obtain design data on the strength of open-channel aluminum-alloy sections subjected to combined column and beam action. The results of the tests of about 70 specimens were graphed for stresses due to axial load and stresses due to bending loading as functions of length to radius of gyration of the specimens. From these graphs a design chart was derived that is suitable for ready use.
Date: September 1939
Creator: Gottlieb, R.; Thompson, T. M. & Witt, E. C.
Partner: UNT Libraries Government Documents Department
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Combustion-engine temperatures by the sodium line-reversal method

Description: The sodium line-reversal method has been used in some preliminary measurements of flame temperature. Improvements in the method involving a photographic recorder and a means of correcting for the dirtiness of the windows are described. The temperatures so obtained are compared with those calculated from pressure diagrams.
Date: March 1936
Creator: Brevoort, Maurice J.
Partner: UNT Libraries Government Documents Department
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Comparative Performance Obtained With XF7C-1 Airplane Using Several Different Engine Cowlings

Description: Discussed here are problems with the use of cowlings with radial air cooled engines. An XF7C-1 airplane, equipped with service cowling and with narrow ring, wide ring, and exhaust collector ring cowlings over the service cowling, was used. For these four cowling conditions, the rate of climb and high speed performance were determined, the cylinder conditions were measured, and pictures to show visibility were taken. The level flight performance obtained with an engine speed of 1900 r.p.m. for t… more
Date: February 1930
Creator: Schey, Oscar W.; Johnson, Ernest & Gough, Melvin N.
Partner: UNT Libraries Government Documents Department
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Comparative Performance of a Powerplus Vane-Type Supercharger and an N.A.C.A. Roots-Type Supercharger

Description: "This report presents the results of tests of a Powerplus supercharger and a comparison of its performance with the performance previously obtained with an N.A.C.A. Roots-type supercharger. The Powerplus supercharger is a positive displacement blower of the vane type having mechanically operated vanes, the movement of which is controlled by slots and eccentrics. The supercharger was tested at a range of pressure differences from 0 to 15 inches of mercury and at speeds from 500 to 2,500 r.p.m." … more
Date: July 1932
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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