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A summary of NACA research on the strength and creep of aircraft structures at elevated temperatures

Description: Report summarizing research on the strength and creep of aircraft structural elements and components at elevated temperatures. Experimental data for aluminum alloy columns, plates, stiffened panels, and multiweb box beams are presented for temperatures up to 600 degrees Fahrenheit and compared with results predicted from materials data.
Date: May 31, 1956
Creator: Heldenfels, Richard R. & Mathauser, Eldon E.
Partner: UNT Libraries Government Documents Department

Tests of artificial flight at high altitudes

Description: From Report: "If we wish to form an accurate idea of the extraordinary progress achieved in aeronautics, a comparison must be made of the latest altitude records and the figures regarded as highest attainable limit some ten years ago. It is desirable, for two reasons, that we should be able to define the limit of the altitudes that can be reached without artificial aid. First, to know to what extent the human body can endure the inhalation of rarified air. Second, the mental capacity of the aviator must be tested at high altitudes and the limit known below which he is able to make reliable observations without being artificially supplied with oxygen. A pneumatic chamber was used for the most accurate observations."
Date: November 1920
Creator: Gradenwitz, Arthur
Partner: UNT Libraries Government Documents Department

Nondestructive Vibratory Testing of Airport Pavements: Volume 1, Experimental Test Results and Development of Evaluation Methodology and Procedure

Description: From abstract: Conventional direct sampling methods of airport pavement evaluation interfere with aircraft operations; therefore, an evaluation procedure based on nondestructive vibratory testing was developed.
Date: September 1975
Creator: Green, James L. & Hall, Jim W.
Partner: UNT Libraries Government Documents Department

Air propellers in yaw

Description: Report presents the results of tests conducted at Stanford University of a 3-foot model propeller at four pitch settings and at 0 degree, 10 degrees, 20 degrees, and 30 degrees yaw.
Date: 1937
Creator: Lesley, E. P.; Worley, George F. & Moy, Stanley
Partner: UNT Libraries Government Documents Department

Air force tests of sperry messenger model with six sets of wings

Description: From Summary: "The purpose of this test was to compare six well-known airfoils, the R.A.F 15, U.S.A. 5, U.S.A. 27, U.S.A. 35-B, Clark Y, and Gottingen 387, fitted to the Sperry Messenger model, at full scale Reynolds number as obtained in the variable density wind tunnel of the National Advisory Committee for Aeronautics; and to determine the scale effect on the model equipped with all the details of the actual airplane. The results show a large decrease in minimum drag coefficient upon increasing the Reynolds number from about one-twentieth scale to full scale. A comparison is made between the results of these tests and those obtained from tests made in this tunnel on airfoils alone."
Date: 1928?~
Creator: Shoemaker, James M
Partner: UNT Libraries Government Documents Department

The analysis of strains indicated by multiple-strand resistance-type wire strain gages used as rosettes

Description: From Summary: "Methods are given for making the necessary corrections to the strains indicated by multiple-strand resistance-type wire strain gages used singly or as rosettes to measure strains at an angle to the principal strain. The results of tests to determine the validity of the methods of correction are reported."
Date: January 1, 1943
Creator: Dow, Norris F
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics of four full-scale propellers having different plan forms

Description: From Introduction: "Its main purpose is to present propeller data for four full-scale propellers of Navy design, three of which have somewhat unusual plan forms and the other one has a normal (usual present-day type) plan form. These data may give some clue as to what may be expected from fundamental changes in blade plan form."
Date: 1938~
Creator: Hartman, Edwin P. & Biermann, David
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of several airfoils of low aspect ratio

Description: From Summary: "This paper presents the results of wind-tunnel tests of several airfoils of low aspect ratio. The airfoils included three circular Clark Y airfoils with different amounts of dihedral, two Clark Y airfoils with slots in their portions, and three flat-plate airfoils. Lift, drag, and pitching-moment characteristics of the slotted airfoils with slots open and closed; pitching moment characteristics of one of the slotted airfoils with slots open and closed; and lift characteristics of the flat-plate airfoils are included. The results reveal a definite improvement of lift, drag, and pitching-moment characteristics with increase in dihedral of the circular Clark Y wing. Lift characteristics near the stall were found to depend markedly on the shape of the extreme tip but were not greatly affected by slots through the after portion of the airfoils. Changes in plan form of the flat-plate airfoils gave erroneous indications of the effect to be expected from changes in plan form of an airfoil of Clark Y section. The minimum drag characteristics of the circular Clark Y airfoils were found to be substantially the same as for a Clark Y airfoil of conventional aspect ratio."
Date: August 1935
Creator: Zimmerman, C H
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics of six commonly used Airfoils over a large range of positive and negative angles of attack

Description: From Summary: "This paper presents the results of tests of six commonly used airfoils: the CYH, the N-22, the C-72, the Boeing 106, and the Gottingen 398. The lifts, drags, and pitching moments of the airfoils were measured through a large range of positive and negative angles of attack. The tests were made in the variable density wind tunnel of the National Advisory Committee for Aeronautics at a large Boeing 106, and the Gottingen 398 airfoils, the negative maximum lift coefficients were found to be approximately half the positive; but for the M-6 and the CYH, which have less effective values were, respectively, 0.8 and 0.6 of the positive values."
Date: November 1931
Creator: Anderson, Raymond F
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of four NACA airfoil sections designed for helicopter rotor blades

Description: From Introduction: "The purpose of the present work is to extend the previous investigation and to derive additional airfoil sections designed to minimize the undesirable characteristics of the previously tested airfoils. The tests of these additional airfoils were made in the Langley two-dimensional low-turbulence tunnel (LTT)."
Date: February 1946
Creator: Rice, Fred J., Jr.
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics of airfoils as affected by surface roughness

Description: From Summary: "The effect on airfoil characteristics of surface roughness of varying degrees and types at different locations on an airfoil was investigated at high values of the Reynolds number in a variable density wind tunnel. Tests were made on a number of National Advisory Committee for Aeronautics (NACA) 0012 airfoil models on which the nature of the surface was varied from a rough to a very smooth finish. The effect on the airfoil characteristics of varying the location of a rough area in the region of the leading edge was also investigated. Airfoils with surfaces simulating lap joints were also tested. Measurable adverse effects were found to be caused by small irregularities in airfoil surfaces which might ordinarily be overlooked. The flow is sensitive to small irregularities of approximately 0.0002c in depth near the leading edge. The tests made on the surfaces simulating lap joints indicated that such surfaces cause small adverse effects. Additional data from earlier tests of another symmetrical airfoil are also included to indicate the variation of the maximum lift coefficient with the Reynolds number for an airfoil with a polished surface and with a very rough one."
Date: April 1933
Creator: HOCKER RAY W
Partner: UNT Libraries Government Documents Department

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 between the highest and lowest values was about 3 percent. The highest efficiencies were for the low-camber sections."
Date: 1939
Creator: Biermann, David & Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department

Analysis and model tests of autogiro jump take-off

Description: From Introduction: "The possibilities of the jump take-off have been established by some full-scale experiments. It is the purpose of this paper to study the factors that govern the jump take-off in its simplest form and to present the results of model tests in which the effect of differences in the rotor parameters was determined."
Date: October 1, 1936
Creator: Wheatley, John B & Bioletti, Carlton
Partner: UNT Libraries Government Documents Department

Creep and Drying Shrinkage of Lightweight and Normal-Weight Concretes

Description: From Scope of Investigation: "The work reported here is part of a continuing program concerning the long-term volume changes in concretes made from lightweight and normal-weight aggregates. The creep, drying-shrinkage, and strength data presented are for concretes made with 24 expanded shale lightweight aggregates and 5 natural, normal-weight aggregates. These aggregates were from widely separated geographical locations and were to be representative samples of aggregates being used in the production of structural concretes."
Date: March 4, 1964
Creator: Reichard, T. W.
Partner: UNT Libraries Government Documents Department

Basic Magnetic Quantities and the Measurement of the Magnetic Properties of Materials

Description: From Introduction: "The work of the Magnetic Measurements Section of the National Bureau of Standards includes (1) testing of specifically prepared test specimens intended for use as standards for checking magnetic testing apparatus (2) investigation and development of magnetic testing apparatus (3) calibration of mutual inductors, test coils, and instruments for measuring magnetic fields, and (4) investigations in the field of magnetics such as studies of phenomena associated with nuclear magnetic resonance or the selection and testing of materials suitable to be used as standards of magnetic susceptibility."
Date: May 21, 1962
Creator: Sanford, Raymond L. & Cooter, Irvine L.
Partner: UNT Libraries Government Documents Department

Tests of Coal and Briquets as Fuel for House-Heating Boilers

Description: From Introduction: "Perhaps the most important result obtained is that showing the relative value of different fuels for domestic purposes. From Table 16. on page 39, it is possible by comparison to arrive at the probable value of any fuel in any part of the country. The figures in the table show that with a sectional boiler the effectiveness of different fuels depends on the number of thermal units they contain. A brief summary of the results of this investigation is given on page 41."
Date: 1911
Creator: Randall, D. T.
Partner: UNT Libraries Government Documents Department

Commercial Deductions from Comparisons of Gasoline and Alcohol Tests on Internal-Combustion Engines

Description: From Introduction: "The following report is a summary of the commercial results which were obtained from 2,000 tests conducted by technologic branch of the United States Geological Survey at St. Louis, Mo., and Norfolk, Va., in 1907 and 1908, under the technical supervision of R.H. Fernald, engineer in charge of the producer-gas section."
Date: 1911
Creator: Strong, Robert M.
Partner: UNT Libraries Government Documents Department

Electric Furnaces for Making Iron and Steel

Description: From Introduction: "Some results of the work already done are presented in this bulletin, which gives a historical review of the development of electric furnaces for making iron and steel, and discusses the problems that remain to be solved in the use of electric furnaces for the smelting of iron ores and the production of pig iron at a profit on a commercial scale."
Date: 1914
Creator: Lyon, Dorsey A. & Keeney, Robert M.
Partner: UNT Libraries Government Documents Department

Electric Switches for use in Gaseous Mines

Description: From Introduction: "The purpose of the investigation discussed in this bulletin, one of a series dealing with the use of electricity in mines, was to study the various means and methods used to confine the flashes that occur when a switch carrying electric current is opened."
Date: 1913
Creator: Clark, H. H. & Crocker, R. W.
Partner: UNT Libraries Government Documents Department