UNT Libraries Government Documents Department - 4,107 Matching Results

Search Results

prev Results: 31 - 54 next
open access

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.
Item Type: Refine your search to only Report
open access

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 fo… more
Date: January 1921
Creator: Norton, F. H. & Bacon, D. L.
Item Type: Refine your search to only Report
open access

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 inclinati… more
Date: January 1921
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
open access

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 angl… more
Date: January 1921
Creator: Davidson, W. E. & Bacon, D. L.
Item Type: Refine your search to only Report
open access

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… more
Date: January 1921
Creator: Heidelberg, V.
Item Type: Refine your search to only Report
open access

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 t… more
Date: January 1921
Creator: Norton, F. H. & Bacon, D. L.
Item Type: Refine your search to only Report
open access

Causes of cracking of ignition cable

Description: From Summary: "The experiments described here show that the cracking at sharp bends, observed in the insulation of internal combustion engine high tension ignition wires after service, is due to a chemical attack upon the rubber by the ozone produced by the electric discharge that takes place at the surface of the cable. This cracking does not occur if the insulating material is not under tension, or if the cable is surrounded by some medium other than air. But it does occur even if the insulat… more
Date: February 1921
Creator: Dempsey, J. B. & Silsbee, F. B.
Item Type: Refine your search to only Report
open access

The Effect of the Nature of Surfaces on Resistance as Tested on Struts

Description: The chief concern was to measure the variations of resistance brought about by the nature of the surface of the struts. The struts were spanned with aviation linen, and then covered with one coat of varnish. The top surface was not perfectly smooth after this treatment, being slightly rough owing to the threads and raised fibers of the fabric. The results of the measurements of the surfaces are shown by the dotted lines of the curves plotted in several figures.
Date: February 1921
Creator: Wieselsberger, G.
Item Type: Refine your search to only Report
open access

Effect of the Reversal of Air Flow Upon the Discharge Coefficient of Durley Orifices

Description: Experiments were conducted to obtain information on the relationship between the coefficients for flow in two directions through thin plate orifices at low velocities. The results indicate that the ratio of the orifice discharge coefficient from standard orifice C(sub s)(sup 1) to the discharge coefficient from the reverse flow C(sub s) is always less than unity with increasing ratio of box area to orifice area. Even for areas as low as twenty, the ratios of the coefficients are not much less t… more
Date: February 1921
Creator: Ware, Marsden
Item Type: Refine your search to only Report
open access

Effect of the Reversal of Air Flow Upon the Discharge Coefficient of Durley Orifices

Description: Note presenting an experiment to obtain information regarding the relationship between the coefficients for flow in the two directions through an inlet. The results indicate that the ratio of the orifice discharge coefficient from standard orifice to the discharge coefficient from reverse flow is always less than unity, but approaches unity with increasing ratio of box area to orifice area, and that even for a ratio of areas as low as twenty the ratios of the coefficients is not much less than … more
Date: February 1921
Creator: Ware, Marsden
Item Type: Refine your search to only Report
open access

Loads and Calculations of Army Airplanes

Description: By comparing airplanes of known strength that have resisted all the usual and even extreme air loads with those that under like conditions were found to be insufficiently strong, the researchers, aided by scientific investigations, developed standards which are satisfactory for the calculation of airplane structures. Given here are standards applicable to loads on wing trusses, load factors for use in stress analysis, load factors required in sand testing, loads on control surfaces, loads on wi… more
Date: February 1921
Creator: Stelmachowski
Item Type: Refine your search to only Report
open access

Airplane Crashes: Engine Troubles: A Possible Explanation

Description: The aim was to bring attention to what might be the cause of some aircraft accidents for which there was no satisfactory explanation. The author notes that in testing aircraft accidents at the Bureau of Standards, it happened frequently that the engine performance became erratic when the temperature of the air entering the carburetor was between 0 C and 20 C. Investigation revealed the trouble to have been caused by the formation and collection of snow somewhere between the entrance to the carb… more
Date: March 1921
Creator: Sparrow, Stanwood W.
Item Type: Refine your search to only Report
open access

Extract From a Report on the Resistance of Spheres of Small Diameter in an Airstream of High Velocity

Description: Much attention is given here to the design of the wind tunnel and the experimental set-up. In comparing their results on the wind resistance of spheres to the results of other researchers, the authors find wide discrepancies. They are unable to explain the cause of the discrepancies, concluding, as they do, that the differing results could not be explained by the action of the wind tunnel walls.
Date: March 1921
Creator: Toussaint & Hayer
Item Type: Refine your search to only Report
open access

The Factors That Determine the Minimum Speed of an Airplane

Description: The author argues that because of a general misunderstanding of the principles of flight at low speed, there are a large number of airplanes that could be made to fly several miles per hour slower than at present by making slight modifications. In order to show how greatly the wing section affects the minimum speed, curves are plotted against various loadings. The disposition of wings on the airplane slightly affects the lift coefficient, and a few such cases are discussed.
Date: March 1921
Creator: Norton, F. H.
Item Type: Refine your search to only Report
open access

Influence of Span and Load Per Square Meter on the Air Forces of the Supporting Surface

Description: "It should be clear that in order to obtain a lift it is necessary that the air which flows past an aerofoil be given a downward acceleration; indeed the lift can be only the reaction produced by the downward acceleration of the flowing air. The motion of the air in the neighborhood of an aerofoil may be followed theoretically with great exactness. In the following, it will be undertaken to make understood, through the simplest possible considerations, the effect of span and loading on the air … more
Date: March 1921
Creator: Betz, A.
Item Type: Refine your search to only Report
open access

Gordon Bennett Airplane Cup 1920

Description: The characteristics of the airplanes built for the Gordon Bennett Airplane Cup race that took place on September 28, 1920 are described. The airplanes are discussed from a aerodynamical point of view, with a number of new details concerning the French machines. Also discussed is the regulation of future races. The author argues that there should be no limitations on the power of the aircraft engines. He reasons that in the present state of things, liberty with regard to engine power does not le… more
Date: April 1921
Creator: Margoulis, W.
Item Type: Refine your search to only Report
open access

On the Resistance of the Air at High Speeds and on the Automatic Rotation of Projectiles

Description: Here, the laws governing the flow of a compressible fluid through an opening in a thin wall are applied to the resistance of the air at high speeds, especially as applied to the automatic rotation of projectiles. The instability which we observe in projectiles shot into the air without being given a moment of rotation about their axis of symmetry, or without stabilizing planes, is a phenomenon of automatic rotation. It is noted that we can prevent this phenomenon of automatic rotation by bringi… more
Date: April 1921
Creator: Riabouchinski, D.
Item Type: Refine your search to only Report
open access

Recent European Developments in Helicopters

Description: Descriptions are given of two captured helicopters, one driven by electric power, the other by a gasoline engine. An account is given of flight tests of the gasoline powered vehicle. After 15 successful flight tests, the gasoline powered vehicle crashed due to the insufficient thrust. Also discussed here are the applications of helicopters for military observations, for meteorological work, and for carrying radio antennas.
Date: April 1921
Item Type: Refine your search to only Report
open access

Similitude tests on wing sections

Description: Report presenting an exploration of the application of model test results to full size construction, which assumes that either the resistance varies as the square of the speed within, the range of speeds in question or that the mechanical similarity law is fulfilled by the model test. The latter requires that the relation of airflow to the model be exactly like that for the large machine.
Date: April 1921
Creator: Kumbruch, H. & Bacon, D. L.
Item Type: Refine your search to only Report
open access

Airplane Superchargers

Description: Discussed here are the principles and operation of aircraft engine superchargers used to maintain and increase engine power as aircraft encounter decreases in the density of air as altitude rises. Details are given on the design and operation of the centrifugal compressors. A method is given for calculating the amount of power needed to drive a compressor. The effects of the use of a compressor on fuel system operation and design are discussed. Several specific superchargers that were in operat… more
Date: May 1921
Creator: Noack, W. G.
Item Type: Refine your search to only Report
open access

On a New Type of Wind Tunnel

Description: Discussed here is a new type of wind tunnel, its advantages, the difficulties attendant upon its use, and the special methods required for its operation. The main difference between the new type of wind tunnel and the ones now in operation is the use of a different fluid. The idea is to diminish the effect of viscosity.
Date: May 1921
Creator: Munk, Max
Item Type: Refine your search to only Report
open access

Absolute Coefficients and the Graphical Representation of Aerofoil Characteristics

Description: It is argued that there should be an agreement as to what conventions to use in determining absolute coefficients used in aeronautics and in how to plot those coefficients. Of particular importance are the absolute coefficients of lift and drag. The author argues for the use of the German method over the kind in common use in the United States and England, and for the Continental over the usual American and British method of graphically representing the characteristics of an airfoil.
Date: June 1921
Creator: Munk, Max
Item Type: Refine your search to only Report
Back to Top of Screen