Technical Report Archive & Image Library (TRAIL) - 134 Matching Results
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- The Aerodynamic Laboratory of the Belgian "Service Technique De L'Aeronautique"
- This report provides a description of the wind tunnel housing and motors at the Belgian Service Technique de L'Aeronautique.
- Aviation Engines in the Endurance Contest
- The contest for engines of great endurance had entries of 13 types by the following firms: Breguet, Farman, Fiat, Hispano-Suiza, Lorraine-Dietrich, Panhard-Levassor, Peugeot, Renault, and Salmson.
- Measuring Vibration and Torque With the Oscillograph
- "The recent development of technical science demands maximum reliability of functioning, together with maximum utilization of construction materials. For this purpose we must know what stresses are produced during functioning. One cause of great stresses are mechanical vibrations and this report describes a method of using an oscilloscope to measure the stresses of rapidly changing phenomena" (p. 1).
- Nomogram for Correcting Drag and Angle of Attack of an Airfoil Model in an Air Stream of Finite Diameter
- In experimenting with airfoil models in a wind tunnel, the magnitude of the forces acting on the model is affected by the fact that the air stream in which the model is suspended, has a restricted cross-section. In order to utilize the results for an airplane in an unlimited quantity of air, a correction must be made. The magnitude of this correction was determined by Prandtl by the application of his wing theory.
- The Testing of Aviation Engines Under Approximate Altitude Conditions
- Note presenting a description of the aviation testing laboratory that has been built at the Bureau of Standards in order to test aviation engines under approximate engine conditions. A description of some of the calculations that are used to compare experimental and theoretical results are provided.
- Tests of rotating cylinders
- Tests were made in the no. 1 (5 ft. atmospheric) wind tunnel at Langley Memorial Aeronautical Laboratory to determine the air forces acting on rotating cylinders with axes perpendicular to the direction of motion. Two cylinders were tested, one with a circular cross-section and the other with a Greek cross. The cross cylinder and compound strut were found to not be as efficient as the circular one.
- The American Airship ZR-3
- This airship was built by the Zeppelin Airship Company at Friedrichshafen in 1923-4, for the United States Navy, as the reparations service of the German Government in fulfillment of the treaty of peace. A description of the design, components, flight characteristics, blueprints, and photographs are provided.
- Effect of Altitude on Power of Aviation Engines
- "These notes are intended to furnish practical and general data on the effect of altitude on engine power. The effective horsepower of an engine is a function of the mean pressure of the fluid acting on the pistons, of the R.P.M. of the engine and of the mechanical efficiency" (p. 1).
- The Simplifying Assumptions, Reducing the Strict Application of Classical Hydrodynamics to Practical Aeronautical Computations
- Note presenting a general method followed to simplify the numerical work in hydrodynamics, which consists of neglecting quantities of a lower order of magnitude. Four of the solutions covered in this report include the theory of the lateral air forces on airship hulls, theory of wing sections in a two-dimensional flow, theory of wings with a finite span, and propeller theory.
- Stieber Dynamometer Hub for Aircraft Propellers
- The knowledge gained from previous experiments and reports was utilized for the construction of a dynamometer hub for 200 mkg (134.4 ft.-lb.) and 1200 kg (2646 lb.) thrust suited for a Liberty "12" engine. A reversing device is also described.
- Structural Weight of Aircraft as Affected by the System of Design
- Various details of design or arrangement of the parts of airplane structures are shown and discussed, the use of these devices having resulted in the production of structures of adequate strength, yet of a weight less than one-half of the usual construction.
- Tests on Duralumin Columns for Aircraft Construction
- The following paper is based on the results of tests, upon duralumin columns, contained in two theses presented to the Department of Civil and Sanitary Engineering of the Massachusetts Institute of Technology.
- Two-Seat Light Airplanes Which Participated in Contest Held at Lympne, England, Week of September 29 to October 4, 1924
- Memorandum presenting a description of a competition to produce an airplane suitable for school work. The characteristics evaluated included the speed range, take off, landing, reliability, and high and low speed are provided. A variety of monoplanes and biplanes were entered and a description of each and their blueprints are provided.
- Calculation of the hull and of the car-suspension systems of airships
- Differential and integral curves are presented and well as numerous calculations relating to hulls. Some of the calculations include those relating to hulls, those relating to the invariability of the shape of the hulls, and those relating to the suspension of the hull.
- Combustion of Liquid Fuels in Diesel Engine
- Hitherto, definite specifications have always been made for fuel oils and they have been classified as more or less good or non-utilizable. The present aim, however, is to build Diesel engines capable of using even the poorest liquid fuels and especially the waste products of the oil industry, without special chemical or physical preparation.
- Duralumin, Its Properties and Uses
- A historical sketch of duralumin is presented, especially in regards to its manufacture by various countries. The properties of duralumin are discussed and strength characteristics listed. Increasing the hardness of duralumin by tempering is discussed as well as the uses of the metal.
- The Logarithmic Polar Curve - Its Theory and Application to the Predetermination of Airplane Performance
- "The logarithmic polar curve has for several years been used by the most prominent aerodynamical laboratories as well as by airplane manufacturers in Europe. To show more clearly the practical application of the polar curve, a series of examples are given with suggestions for solution. After a discussion of the theory and the practical application of the polar curve, the following problems are discussed: climbing flight, speed at various altitudes, and the characteristics of two seater observation airplanes of recent design" (p. 1).
- Mooring Airships
- The purpose of this paper is to summarize the present status of the problem of mooring airships. Mooring with one, two and even three cables are all discussed.
- Results of Experiments With Slotted Wings
- This report recounts some of the successful experiments conducted in England and Germany on slotted wings and ailerons. Wind tunnel test results are given and examples of aircraft constructed with these new wing components are described.
- Effect of Ratio Between Volume and Surface Area of Airships
- Report presenting an exploration of the concept that the ratio between the volume and the surface area also exerts an influence on other secondary characteristics of airships.
- Experimental Investigation of the Effect of an Oscillating Airstream (Katzmayr Effect) on the Characteristics of Airfoils
- A series of experiments were conducted related to the action of an airstream oscillating vertically on supporting surfaces. The object of the experiments was to verify the very interesting results of Mr. Katzmayr, Director of the Vienna Aerodynamics Laboratory, and, if possible, to obtain more complete data on the effect of the amplitude and velocity of the oscillations of the airstream. The results obtained by Mr. Katzmayr are briefly summarized. The conduct of the numerous experiments to verify his results are described in detail. Experimental results are given in tabular and graphical form.
- Experiments in the Use of Back Pressures on Oil Wells
- Technical paper issued by the Bureau of Mines over experiments conducted on the back pressure of oil wells. The results of the experiments are presented and discussed. This paper includes tables, photographs, and illustrations.
- General Rules for Metal Aircraft Construction
- "The Commissariat of Aviation deems it expedient to issue a few rules of a general character which should be followed by constructors in designing aircraft, into the manufacture of which metal enters to a considerable extent. The materials covered include: aluminum, duralumin, soft steel, high-resistance steel, in sheets, tubing, and shaped elements" (p. 1).
- Micarta propellers IV : technical methods of design
- A description is given of the methods used in design of Micarta propellers. The most direct method for working out the design of a Micarta propeller is to start with the diameter and blade angles of a wooden propeller suited for a particular installation and then to apply one of the plan forms suitable for Micarta propellers. This allows one to obtain the corresponding blade widths and to then use these angles and blade widths for an aerodynamic analysis.
- Motive Power Required to Operate a Wind Tunnel
- The use of exit cones and different blade configurations to reduce the motive power required in wind tunnels is discussed in this report.
- Provisional Rules for the Inspection of Aircraft Adopted by the French Bureau Veritas
- These new regulations are intended to replace those of November 1, 1922, and give the directions to be followed in the supervision of aircraft by the agents of the Aeronautical Section of the Bureau Veritas. The rules consist of four sections: rules regarding an aircraft leaving a repair shop, the objects of quarterly and weekly inspections, and rules regarding the upkeep and repair of airplanes.
- Recent Researches in Airship Construction 3: A New Type of Nonrigid Airship
- The author describes experiments in designing nonrigid airships. A nonrigid airship of 32,000 cubic meters, the PL 27 withstood all stresses with 20 kg/m(exp 2) hull pressure during its life of two years. The moment of resistance is known, as also the stresses in the envelope for the given hull pressure. The mean internal pressure necessary to give the airship the requisite rigidity and to prevent buckling was also investigated.
- A Short Method of Calculating Torsional Stresses in an Airplane Fuselage
- "This report deals with an investigation carried out in the Civil Engineering Laboratory of the University of California, to determine the accuracy of existing methods of computing the stresses in an airplane fuselage when subjected to torsion, and to derive a simple approximate formula for the rapid calculation of these stresses. The formula is derived by using the customary least work equation and considering each bay separately" (p. 1).
- A Study of Static Stability of Airships
- The first section deals with the theoretical side of statical stability of airships in general. The second section deals with preliminary tests of the model and experiments for the determination of effects due to change of tail area, aspect ratio, tail form, and tail thickness.
- Revision of the American Pikas (Genus Ochotona)
- Discusses distribution, habitat, habits, pelage, molt, specimens, history, and nomenclature of pikas. Provides descriptions, locations, and a key for species and subspecies.
- Formulas, Tables and Curves for Computing the Mutual Inductance of Two Coaxial Circles
- Scientific paper issued by the Bureau of Standards over the mutual inductance of two coaxial circles. As stated in the abstract, "a number of examples are given to show the methods of computation by the different formulas, tables, and charts" (p. 541). This paper includes tables, and illustrations.
- Gas Masks for Gasoline and Petroleum Vapors
- Technical paper issued by the Bureau of Mines over gas masks developed for gasoline and petroleum vapors. Descriptions of different types of gas masks developed are presented. This paper includes tables, photographs, and illustrations.
- Historical Notes on Aerodynamic Research
- "It is obviously interesting to know the names of those who were the first contributors to aeronautical science. Therefore, without claiming to give a complete history, I present in this article a summary list of names in chronological order relating to the history of experiments on the resistance of the air and its application to aeronautics" (p. 1).
- Micarta Propellers 1: Materials
- Here, values for tension, compression edgewise of laminations, and transverse flatwise of laminations are given for Micarta made with various kinds of sheet material. The corresponding values for white oak are given for comparison. It was found by destructive and service tests that Micarta made with a good grade of cotton duck will give satisfactory service with most designs.
- Micarta Propellers 2: Method of Construction
- The methods used in manufacturing Micarta propellers differ considerably from those employed with wood propellers on account of the hardness of the materials. The propellers must be formed accurately to size in a mold and afterwards balanced without the customary trimming of the material from the tips. Described here are the pressing and molding processes, filing, boring, balancing, and curing.
- Micarta Propellers III: General Description of the Design
- The design of propellers made of Micarta is discussed. The advantages of the material are noted, especially as compared with wood. The design changes necessitated by the use of Micarta are discussed with reference to the hub boss, the narrowing of the blade tips, the thinning of the blades, the angles of the leading and trailing edges, and the adjustment of the pitch. Results of flight tests show that the Micarta propeller gave a top speed of 2 miles per hour more than the wooden propeller while turning about 120 r.p.m slower, with about the same rate of climb.
- Recent Researches in Airship Construction 1: Forces of Flow on a Moving Airship and the Effect of the Control Surfaces
- The problems as to how an airship can best be stabilized and steered and to what stresses it is subjected in the air, are so important as to determine in large measure the future development of airships much more than formerly when velocities of 30-35 meters (98-115 feet) per second were not known and the effects of the air flow were not so great.
- Recent Researches in Airship Construction 2: Bending Stresses on an Airship in Flight
- The first part of this report shows the differences between commercial and war airships and then goes on to show how some of the problems were solved. Their thorough investigations of these problems finally enabled the Schutte-Lanz Company to construct bulkhead diagrams for determining the buoyancy of airships, by means of which the size of each cell was established. These diagrams were derived from bulkhead diagrams employed in ship designing and are used in a similar manner.
- Structural and Economic Limits to the Dimensions of Airships
- "In opposition to the advantage of larger dimensions, there is one disadvantage, namely, the weight of the structure increases more rapidly than the buoyancy. It is not possible, however, to determine a general law. In order to formulate one having the merit of simplicity, we will divide the structure into two parts: one subject to tensile and compressive stresses, varying directly as the ascensional or lifting forces; the other subject to varying stresses of the surface areas" (p. 1).
- Balloon Flight and Atmospheric Electricity
- "The air is known to be charged with electricity (chiefly positive) with reference to the earth, so that its potential increases with the altitude and the difference in potential between two points in the same vertical line, divided by the distance between them, gives a value called the "potential gradient," which may vary greatly with the altitude, the nature of the ground and the atmospheric conditions" (p. 1).
- Experiments on the Resistance of Airplane Wheels and Radiators
- Experiments were made on the resistance of four airplane wheels of different sizes and coverings and two Lamblin radiators. The results show the important influence of the wheel coverings. The closing of a shutter, which was fitted to one of the radiators, considerably lessened the resistance.
- Experiments With a Device for Shortening the Glide and Landing Run of an Airplane
- The improvement of airplanes and increased safety of air traffic can be sought in various ways. In the experiments described below, the aim was to find some simple and inexpensive method of modifying present-day airplanes, so as to improve and simplify the process of landing.
- The Problem of Liquid Fuels (for Aircraft Engines)
- "The crisis which troubles the world market for liquid fuel in general and for carburants in particular is doubtless one of the most serious ever experienced by modern industry. It is a national crisis of economic and political independence for countries like Italy and France. The solutions suggested for meeting the lack of liquid fuel may be summed up under two general headings: the economical use of the petroleum now available; creation of petroleum substitutes from natural sources within the country" (p. 1).
- Some Tables of the Factor of Apparent Additional Mass
- "This note, prepared for publication by the National Advisory Committee for Aeronautics, is a collection of the tables of the factor of apparent mass that have been published up to now. The theory of the motion of solids in a perfect fluid is of the greatest value for the study of most aerodynamic problems, and the additional apparent mass of an immersed solid is the most important characteristic for such theoretical numerical computations. It will therefore be helpful to have the most important values of the apparent mass - for some elementary cases - collected in a convenient form" (p. 1).
- Temperatures in Cabs of Freight Locomotives Passing Through Tunnels of the Chesapeake & Ohio Railroad
- Report issued by the U.S. Bureau of Mines on experiments conducted to improve the cab conditions of freight engines. The temperature, gas content, and other properties are presented. This report includes tables, graphs, and illustrations.
- Velocity and Pressure Distribution Behind Bodies in an Air Current
- The following experiments on the air flow behind bodies were made for the purpose of assisting in the explanation of the phenomena connected with air resistance. The first two series of experiments dealt with the phenomena behind a cylinder. The third series of experiments was carried out behind a streamlined strut.
- Theory of Determination of Ultra-Radio Frequencies by Standing Waves on Wires
- Scientific paper issued by the Bureau of Standards over ultra-radio frequencies. As stated in the abstract, "this paper furnishes the theoretical background for the method of frequency standardization employing short standing waves on parallel wires" (p. 487). This paper includes tables, and illustrations.
- Air Forces Exerted on Streamlined Bodies with Round or Square Cross- Sections, When Placed Obliquely to the Airstream
- "The question of behavior of a streamlined body with round or square cross-sections is of importance in determining the shape to give an airplane fuselage. It is our task here to show how the lift and drag are affected, with the object placed obliquely to the air stream" (p. 1).
- Development of Wing-Steered Messerschmitt Gliders
- The present article is a brief report on the development and testing of the Messerschmidt glider that set a duration record of 21 minutes. Its most conspicuous characteristic was the placing of the steering gear entirely inside the fuselage and wings.
- Device for Measuring Sound in Airplane Engines
- Memorandum describing a device, constructed according to the system of Gati, with which it is possible to measure the sound of an engine and test the effect of a silencer.