Technical Report Archive & Image Library (TRAIL) - 99 Matching Results

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Goldstein's Solution of the Problem of the Aircraft Propeller With a Finite Number of Blades

Description: This report examines the Betz theory on frictionless, lightly loaded propellers and Prandtl's addendum extended to moderately loaded propellers. The author then goes on to extend the discussion to Goldstein's solution for propellers with a finite number of blades.
Date: December 1931
Creator: Helmbold, H. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic and Aerodynamic Tests of Four Models of Outboard Floats: (N.A.C.A. Models 51-A, 51-B, 51-C, and 51-D)

Description: Four models of outboard floats (N.A.C.A. models 51-A, 51-B, 51-C, and 51-D) were tested in the N.A.C.A. tank to determine their hydrodynamic characteristics and in the 20-foot wind tunnel to determine their aerodynamic drag. The results of the tests, together with comparisons of them, are presented in the form of charts. From the comparisons, the order of merit of the models is estimated for each factor considered. The best compromise between the various factors seems to be given by model 51-D.… more
Date: December 1938
Creator: Dawson, John R. & Hartman, Edwin P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The influence of wing setting on the wing load and rotor speed of a PCA-2 autogiro as determined in flight

Description: Flight tests were made on PCA-2 autogiro with wing settings of 2.2 degrees, 0.9 degrees, and -0.5 degrees. The wing load and rotor speed were measured in steady glides. The results obtained show that a wide variation in rotor speed as a function of air speed can be obtained by a suitable adjustment of the wing setting; that by decreasing the wing setting the upper safe flying speed, determined by the decrease is rotor speed, is greatly increased; and that the interference of the wing on the rot… more
Date: December 28, 1934
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The interference effects on an airfoil of a flat plate at mid-span position

Description: "This report gives the results of an investigation of the mutual interference of an airfoil and a flat plate inserted at mid-span position. The tests were conducted in the Variable-Density Wind Tunnel of the National Advisory Committee for Aeronautics at a high value of the Reynolds Number. The interference effects of this combination were found to be small. Supplementary tests indicated that the use of fillets decreases both the lift and drag slightly. A bibliography of publication dealing wit… more
Date: December 1931
Creator: Ward, Kenneth E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquid Cooling of Aircraft Engines

Description: This report presents a method for solving the problem of liquid cooling at high temperatures, which is an intermediate method between water and air cooling, by experiments on a test-stand and on an airplane. A utilizable cooling medium was found in ethylene glycol, which has only one disadvantage, namely, that of combustibility. The danger, however is very slight. It has one decided advantage, that it simultaneously serves as protection against freezing.
Date: December 1931
Creator: Weidinger, Hanns
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Local instability of columns with I-, Z-, channel, and rectangular-tube sections

Description: From Summary: "Charts are presented for the coefficients in the formulas for the critical compressive stress at which cross-sectional distortion begins in thin-wall columns of I-, Z-, channel, and rectangular-tube sections. The energy method of Timoshenko was used in the theoretical calculations required for the construction of the charts. The deflection equations were carefully selected to give good accuracy. The calculation of the critical compressive stress at stresses above the elastic rang… more
Date: December 1939
Creator: Stowell, Elbridge Z. & Lundquist, Eugene E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mammals of New Mexico

Description: Summary of the species of mammals native to New Mexico, including a map of the life zones, descriptions of the physiographic features, and lists of characteristic zone-marking plants, birds, mammals.
Date: December 1931
Creator: Bailey, Vernon
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Maneuverability investigation of an F6C-4 fighting airplane

Description: "In order to compare the relative maneuverability of two fighting airplanes and to accumulate additional data to assist in establishing a satisfactory criterion for the maneuverability of any airplane, the National Advisory Committee for Aeronautics has conducted maneuverability investigations on the F6C-3 (water-cooled engine) and the F6C-4 (air-cooled engine) airplanes. The investigation made on the F6C-3 airplane was reported in NACA-TR-369. This report contains the results of the investigat… more
Date: December 12, 1930
Creator: Dearborn, C. H. & Kirschbaum, H. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Meteorological Conditions During the Formation of Ice on Aircraft

Description: These are the results of a number of records recently secured from autographic meteorological instruments mounted on airplanes at times when ice formed. Ice is found to collect on an airplane only when the airplane is in some form of visible moisture, such as cloud, fog, mist, rain. etc., and the air temperature is within certain critical limits. Described here are the characteristics of clear ice and rime ice and the specific types of hazards they present to airplanes and lighter than air vehi… more
Date: December 1932
Creator: Samuels, L. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Method of Determining the Weights of the Most Important Simple Girders

Description: "This paper presents a series of tables for the simple and more common types of girders, similar to the tables given in handbooks under the heading "Strength of Materials," for determining the moments, deflections, etc., of simple beams. Instead of the uniform cross section there assumed, the formulas given here apply only to girders of "uniform strength," i.e., it is assumed that a girder is so dimensioned that a given load subjects it to a uniform stress throughout its whole length. This prin… more
Date: December 1931
Creator: Cassens, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modern Methods of Testing

Description: After a brief survey of the commonly used single-value test methods, the importance of the determination of the incipient knock for the octane number is discussed and improvements suggested for the knock testing in the CFR engine. The DVL supercharge test method with its superiority of direct determination of fuel knock in each single cylinder of an airplane engine without involving structural changes, is described and the advantages of a multiple-value method enumerated. A diagrammatic present… more
Date: December 1939
Creator: Seeber, F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Noise From Propellers With Symmetrical Sections at Zero Blade Angle, 2

Description: "In a previous paper (Technical Note No. 605), a theory was developed that required an empirical relation to calculate sound pressures for the higher harmonics. Further investigation indicated that the modified theory agrees with experiment and that the empirical relation was due to an interference phenomenon peculiar to the test arrangement used. Comparison is made between the test results for a two-blade arrangement and the theory" (p. 1).
Date: December 1938
Creator: Deming, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Observations in Flight of the Region of Stalled Flow Over the Blades of an Autogiro Rotor

Description: "The flow over the inner halves of the rotor blades on a Kellet YG-1B autogiro was investigated in flight by making camera records of the motion of silk streamers attached to the upper surfaces of the blades. These records were analyzed to determine the boundaries of the region within which the flow over the blade sections was stalled for various tip-speed ratios. For the sake of comparison, corresponding theoretical boundaries were obtained. Both the size of the stalled area and its rate of gr… more
Date: December 1939
Creator: Bailey, F. J., Jr. & Gustafson, F. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Open Schedules for Gold and Silver Ores and Concentrates at Western Custom Smelters

Description: Report issued by the U.S. Bureau of Mines discussing the smelting schedules for the operators of silver and gold mines. As stated in the introduction, "the paper discusses smelting schedules, general smelting practices that have a bearing on rates, and the reasons for penalties or credits for certain constituents of ores" (p. 1). This report includes tables.
Date: December 1936
Creator: Gardner, E. D. & Allsman, Paul T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A photographic study of combustion and knock in a spark-ignition engine

Description: Report presents the results of a photographic study of the combustion in a spark-ignition engine using both Schlieren and flame photographs taken at high rates of speed. Although shock waves are present after knock occurs, there was no evidence of any type of sonic or supersonic compression waves existing in the combustion gases prior to the occurrence of knock. Artificially induced shock waves in the engine did not in themselves cause knock.
Date: December 6, 1937
Creator: Rothrock, A. M. & Spencer, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Photomicrographic studies of fuel sprays

Description: A large number of photomicrographs of fuel sprays were taken for the purpose of studying the spray structure and the process of spray formation. They were taken at magnifying powers of 2.5, 3.25, and 10, using a spark discharge of very short duration for illumination. Several types and sizes of nozzles were investigated, different liquids were used, and a wide range of injection pressures was employed. The sprays were photographed as they were injected into a glass-walled chamber in which the a… more
Date: December 15, 1932
Creator: Lee, Dana W. & Spencer, Robert C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Plastics as structural materials for aircraft

Description: The purpose here is to consider the mechanical characteristics of reinforced phenol-formaldehyde resin as related to its use as structural material for aircraft. Data and graphs that have appeared in the literature are reproduced to illustrate the comparative behavior of plastics and materials commonly used in aircraft construction. Materials are characterized as to density, static strength, modulus of elasticity, resistance to long-time loading, strength under repeated impact, energy absorptio… more
Date: December 1937
Creator: Kline, G. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Practical Experiences With Lightning Discharges to Airplanes

Description: The present report describes many cases of airplanes being struck by lightning and the measures that can be taken to minimize damage to them. The data indicates that the hazard to airplanes from lightning is overestimated and that dangers can be minimized by appropriate weather forecasts and training of the pilots.
Date: December 1933
Creator: Koppe, Heinrich
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pressure-Distribution Measurements on a Rectangular Wing With a Partial-Span Split Flap in Curved Flight

Description: "Pressure-distribution tests were made on the 32-foot whirling arm of the Daniel Guggenheim Airship Institute of a rectangular wing of NACA 23012 section to determine the rolling and the yawing moment due to angular velocity in yaw. The model was tested at 0 and 5 degree pitch; 0, +/- 5, and +/- 10 degrees yaw; and with no flap and with split flaps 25, 50 and 75 percent of the wing span and deflected 60 degrees. The results are given in the form of span load distributions and as calculated mome… more
Date: December 1939
Creator: Rokus, Frank G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pressure-distribution measurements on O-2H airplane in flight

Description: "Results are given of pressure-distribution measurements made over two different horizontal tail surfaces and the right wing cellule, including the slipstream area, of an observation-type biplane. Measurements were also taken of air speed, control-surface positions, control-stick forces, angular velocities, and accelerations during various abrupt maneuvers. These maneuvers consisted of push-downs and pull-ups from level flight, dive pull-outs, and aileron rolls with various thrust conditions" (… more
Date: December 8, 1936
Creator: Pearson, H. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pressure Distribution Over a Clark Y-H Airfoil Section With a Split Flap

Description: "An investigation was made in the N.A.C.A. 7 by 10 foot wind tunnel of the distribution of air pressure over one chord section of a Clark Y-H airfoil with a split flap. The results obtained are given in the form of diagrams showing the chordwise distribution of pressure on both airfoil and flap as plots of calculated aerodynamic coefficients for both airfoil and flap" (p. 1).
Date: December 1937
Creator: Wenzinger, Carl J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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