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Index Generum Mammalium: a List of the Genera and Families of Mammals

Description: This report consists of three parts: (1) An annotated list of the generic names of mammals; (2) an alphabetical list of the families of mammals, and (3) a classified list of the generic names, arranged by orders and families.
Date: January 23, 1904
Creator: Palmer, T. S.
Partner: UNT Libraries Government Documents Department
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Special Studies in Electrolysis Mitigation: 4. A Preliminary Report on Electrolysis Mitigation in Elyria, Ohio, with Recommendations for Mitigation

Description: Technical paper issued by the Bureau of Standards over surveys conducted on the electrical conditions of railway tracks in Elyria, Ohio. The results of the surveys are presented and discussed. This paper includes tables, maps, and illustrations.
Date: January 22, 1916
Creator: McCollum, Burton & Logan, K. H.
Partner: UNT Libraries Government Documents Department
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Durability of Stucco and Plaster Construction: Progress Report Containing Results of Investigations up to April, 1916

Description: Technical paper issued by the Bureau of Standards over tests conducted on the durability of stucco construction. Construction methods are discussed. The test results are presented and discussed as well. This paper includes tables, illustrations, and photographs.
Date: January 31, 1917
Creator: Wig, R. J.; Pearson, J. C. & Emley, W. E.
Partner: UNT Libraries Government Documents Department
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Airplane stress analysis

Description: Report presents stress analysis of individual components of an airplane. Normal and abnormal loads, sudden loads, simple stresses, indirect simple stresses, resultant unit stress, repetitive and equivalent stress, maximum steady load and stress are considered.
Date: January 1918
Creator: Zahm, A. F. & Crook, L. H.
Partner: UNT Libraries Government Documents Department
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Efflux of Gases Through Small Orifices

Description: Scientific paper issued by the Bureau of Standards over studies conducted on gas effusion rates. The methods used and the results of the studies are presented and discussed. This paper includes tables, and illustrations.
Date: January 28, 1920
Creator: Buckingham, Edgar & Edwards, Junius David
Partner: UNT Libraries Government Documents Department
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Comparison of hecter fuel with export aviation gasoline

Description: Among the fuels which will operate at compression ratios up to at least 8.0 without preignition or "pinking" is hecter fuel, whence a careful determination of its performance is of importance. For the test data presented in this report the hecter fuel used was a mixture of 30 per cent benzol and 70 per cent cyclohexane, having a low freezing point, and distilling from first drop to 90 per cent at nearly a constant temperature, about 20 degrees c. below the average distillation temperature ("mean volatility") of the x gasoline (export grade). The results of these experiments show that the power developed by hecter fuel is the same as that developed by export aviation gasoline at about 1,800 r.p.m. at all altitudes. At lower speeds differences in the power developed by the fuels become evident. Comparisons at ground level were omitted to avoid any possibility of damaging the engine by operating with open throttle on gasoline at so high a compression. The fuel consumption per unit power based on weight, not volume, averaged more than 10 per cent greater with hecter than with x gasoline. The thermal efficiency of the engine when using hecter is less than when using gasoline, particularly at higher speeds. A generalization of the difference for all altitudes and speeds being 8 per cent. A general deduction from these facts is that more hecter is exhausted unburnt. Hecter can withstand high compression pressures and temperature without preignition. (author).
Date: January 29, 1920
Creator: Dickinson, H. C.; Gage, V. R. & Sparrow, S. W.
Partner: UNT Libraries Government Documents Department
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The 300 H.P. Benz Aircraft Engine

Description: This report provides a description of the Benz 300 H.P. aircraft engine containing 12 cylinders placed at a 60° angle. It includes a detailed description of the development of the constructional points, particularly the cylinders, pistons, and connecting rods, as well as the engine fitting, lubrication, oil pumps, bearings, oil tank, fuel pump, carburetors, and cooling system. There are seven pages of illustrative figures at the end of the report.
Date: January 1921
Creator: Heller, A.
Partner: UNT Libraries Government Documents Department
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N.A.C.A. Langley field wind tunnel apparatus: The tilting manometer

Description: A description is given of a tilting manometer designed to meet the requirements of a manometer for use in the wind tunnel at the Langley Memorial Aeronautical Laboratory. This gauge was designed to meet the requirements of a manometer in use in connection with a static pressure plate to indicate the wind speed in the tunnel. The requirements are noted. The sensitivity of the gauge must be made inversely proportional to the pressure to be measured. The gauge must be accurately and quickly set for any desired pressure.
Date: January 1921
Creator: Norton, F. H. & Bacon, D. L.
Partner: UNT Libraries Government Documents Department
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The determination of downwash

Description: It is obvious that, in accordance with Newton's second law, the lift on an aerofoil must be equal to the vertical momentum communicated per second to the air mass affected. Consequently a lifting aerofoil in flight is trailed by a wash which has a definite inclination corresponding to the factors producing the lift. It is thought that sufficient data, theoretical and experimental, are now available for a complete determination of this wash with respect to the variation of its angle of inclination to the originating aerofoil and with respect to the law which governs its decay in space.
Date: January 1921
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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The determination of the effective resistance of a spindle supporting a model aerofoil

Description: An attempt was made to determine the effect of spindle interference on the lift of the airfoil by measuring moments about the axis parallel to the direction of air flow. The values obtained are of the same degree as the experimental error, and for the present this effect will be neglected. The results obtained using a U.S.A. 15 wing (plotted here) show that the correction is nearly constant from 0 degrees to 10 degrees incidence and that at greater angles its value becomes erratic. At such angles, however, the wing drag is so high that the spindle correction and its attendant errors become relatively small and unimportant.
Date: January 1921
Creator: Davidson, W. E. & Bacon, D. L.
Partner: UNT Libraries Government Documents Department
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Measurements of Rudder Moments on an Airplane During Flight

Description: Tests indicated that: 1) C airplanes with two struts are extremely susceptible to aileron maneuvers, slight alterations of the aileron sufficing to compensate great unequalized moments; 2) great unequalized moments can be produced or neutralized by the unequalized alternation of the angle of attack below the outer and inner struts. Adjustment below the outer strut is the more effective of the two. 3) When a load of bombs is suspended beyond the center of the airplane, below the wings, the bombs need not be dropped simultaneously. 4) The propeller wash of a wide open engine has considerable influence on the position and operation of the elevator. The elevator is more susceptible in flight with the engine running than in gliding flight. 5) Adjustable tail planes are not advisable for D airplanes, nor for the C type, but they are, on the other hand, to be recommended for large size and giant airplanes in which the center of gravity changes during flight. 6) The aileron values obtained by wind tunnel measurements are about 10 percent too low, though otherwise applicable. For the elevator, the results of such measurements should be taken as mean values between flight with the engine running and gliding flight.
Date: January 1921
Creator: Heidelberg, V.
Partner: UNT Libraries Government Documents Department
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New Lateral Stabilizing Device for Airplanes

Description: "The proposed device tends to render the lateral stabilization of airplanes easier and more efficacious. The proposed solution is to mount the ailerons independently, in such a manner that they can turn freely, under the action of the relative wind, about an axis located in front of the extreme position of the center of the lift" (p. 1).
Date: January 1921
Creator: Constantin, Louis
Partner: UNT Libraries Government Documents Department
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On the Resistance of Spheres and Ellipsoids in Wind Tunnels

Description: Note presenting a study of the influence exercised on the results of measurements by the dimensions and type of the tunnels used in aerodynamic laboratories, and on the comparison of the results with observations made in motionless and unlimited air.
Date: January 1921
Creator: Riabouchinsky, D. P.
Partner: UNT Libraries Government Documents Department
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The optical wing aligning device of the Langley Field tunnel

Description: Described here is a convenient and accurate method of aligning the wing chord with the airflow. The device was developed to permit rapid and accurate alignment of airfoils and models with the airstream passing through the tunnel. It consists of three main parts: a projector, a reflector, and a target. The arrangement, which is shown in a figure, has proven satisfactory in operation. It is far better than the old method of sighting across a long batten, as the operator of a balance may see the target and correctly judge the accuracy of his alignment. Whereas the old method required two operators and several minutes time to align to within 1/10 degree, this method enables one operator to align a wing to within 1/100 of a degree in a few seconds. This method also has the advantage of being able to measure the angle of the wing while the tunnel is running. Thus, the true angle of incidence is shown.
Date: January 1921
Creator: Norton, F. H. & Bacon, D. L.
Partner: UNT Libraries Government Documents Department
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Aerial navigation : on the problem of guiding aircraft in a fog or by night when there is no visibility

Description: Report discussing the use of magnetic fields and wire to navigate aircraft in conditions of poor visibility is presented. This field may be considered to be derived from a double lemniscate, considered in the particular case where the origin is a double point formed from the magnetic field of the slack wire, from the field produced by the return currents and from the field due to the currents induced in the conducting mass. These fields are dephased in two ways, one in the direction of the wire, the other in a direction perpendicular to it.
Date: January 1922
Creator: Loth, William
Partner: UNT Libraries Government Documents Department
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Behavior of Aviation Engines at Different Air Densities

Description: The author expresses his views that engine performance would be affected only at very low temperatures is presented in this report.
Date: January 1922
Creator: Schwager, O.
Partner: UNT Libraries Government Documents Department
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The Dead Weight of the Airship and the Number of Passengers That Can Be Carried

Description: In order to determine an approximate formula giving the weight of a dead load as a function of the volume (V) of the envelope and of the maximum velocity (v), we will take the relative weight of the various parts of the airship (P(sub v), M, V, A, T(sup 34)), adopting a mean value of the coefficients determined. This formula may be adopted both for semi-rigid airships with suspended nacelle and non-rigid envelope, with or without internal suspensions. It may also be adapted to airships with rigid longitudinal beam, with power units on external supports or in nacelles, and with non-rigid envelopes, with or without internal bracing cables.
Date: January 1922
Creator: Crocco
Partner: UNT Libraries Government Documents Department
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Effect of aerofoil aspect ratio on the slope of the lift curve

Description: On of the most important characteristics of an airfoil is the rate of change of lift with angle of attack, (sup dC)L/d alpha. This factor determines the effectiveness of a tail plane in securing static longitudinal stability. The application of the Gottingen formulas given here for calculating the variation of (sup Dc)L/d alpha with aspect ratio should be of interest to many aeronautical engineers. For the convenience of the engineer, a set of curves calculated by the method set forth here are given in graphical form. Also, the observed values of (sup dC)L/d alpha for the same airfoil at various aspect ratios follow the calculated curves closely.
Date: January 1922
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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The Glider of the College Aviation Group of the Technical High School, Hanover

Description: This report presents the results of testing on a glider designed and built by the College Aviation Group. The design and construction were based on the following principles: 1) the glider will be made to descend as slowly as possible; 2) rigidity and resistance were arranged to meet the conditions of varied loads; 3) construction is as simple as possible; 4) and great ease in assembling and dismounting have been sought.
Date: January 1922
Creator: Blume, W.
Partner: UNT Libraries Government Documents Department
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Langley Field wind tunnel apparatus

Description: This report is broken up into two sections: one about the regulators for speed of wind tunnel drive motor and one about a vernier manometer with adjustable sensitivity.
Date: January 1922
Creator: Bacon, D. L.
Partner: UNT Libraries Government Documents Department
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Notes on the construction and testing of model airplanes

Description: Here, it is shown that the construction of an airplane model can and should be simplified in order to obtain the most reliable test data. General requirements for model construction are given, keeping in mind that the general purpose of wind tunnel tests on a model airplane is to obtain the aerodynamic characteristics, the static balance, and the efficiency of controls for the particular combination of wings, tail surfaces, fuselage, and landing gear employed in the design. These parts must be exact scale reproductions. Any appreciable variation from scale reproduction must be in the remaining parts of the model, i.e., struts, wires, fittings, control horns, radiators, engines, and the various attachments found exposed to the wind in special airplanes. Interplane bracing is discussed in some detail.
Date: January 1922
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
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A Preliminary Investigation of a New Method for Testing Aerofoils in Free Flight

Description: "This report is a description of a new method of testing aerofoils in free flight devised by the National Advisory Committee for Aeronautics. The method consists in lowering below a flying airplane a large inverted aerofoil on three small steel wires in such a way that the lift on the aerofoil always keeps the wires tight. The resultant force is measured by the tension in the wires, and the direction of the resultant by the amount the wing trails backwards" (p. 1).
Date: January 1922
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department
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Recent Progress in the Theory of Air Flow as Applied to Aeronautics

Description: In summing up it may be said that the hydrodynamic theories are best confirmed by experimental results for bodies with small resistance or drag and can accordingly be used in place of experimental tests.
Date: January 1922
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department
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