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- Aerodynamic forces and moments of a seaplane on the water
- From Introduction: "This report gives the results of wind-tunnel tests with a seaplane model as a contribution to the solution of the aerodynamic problems."
- The Aerodynamic Forces and Moments on a Spinning Model of the F4B-2 Airplane as Measured by the Spinning Balance
- "The tests described in this report were made as part of an investigation of the spinning characteristics of the F4B-2 airplane conducted at the request of the Bureau of Aeronautics, Navy Department" (p. 1).
- Aerodynamic Investigation of a Cup Anemometer
- Results of an investigation wherein the change of the normal force coefficient with Reynolds Number was obtained statically for a 15.5-centimeter hemispherical cup.
- Aerodynamic principles of the direct lifting propeller
- From Summary: "The purpose of this report is to make the complicated processes on the direct-lift propeller amenable to analysis and observation. This is accomplished by placing the physical phenomena, starting with the most elementary process, in the foreground, while limiting the mathematical treatment to the most essential in view of the fundamental defects of the theorems. Comparison with model experiments supplements and corroborates the theoretical results."
- Aerodynamic Rolling and Yawing Moments Produced by Floating Wing-Tip Ailerons, as Measured by Spinning Balance
- From Summary: "The investigation described in this report was made to determine the effectiveness of floating wing-tip ailerons as an airplane control in the spin. In these tests the ailerons, not being balanced, were set parallel to the axis of rotation, which is probably very nearly the attitude that balanced floating ailerons would assume in a spin. Rolling - and yawing moment coefficients are given as measured for the model with and without the ailerons, and computed values are given for the ailerons alone."
- The aerodynamic safety of airplanes
- This report presents several hypotheses regarding airplane safety, mainly concerning the nondimensional coefficient of air, speed, acceleration, and wing area on aerodynamic considerations of safety.
- Aerodynamic tests of a low aspect ratio tapered wing with an auxiliary airfoil for use on tailless airplanes
- From Introduction: "The present report gives the results of tests made on a tapered wing with a nontapered auxiliary airfoil affixed to it. The wing was the one used in reference 7."
- Aerodynamic tests of a low aspect ratio tapered wing with various flaps, for use on tailless airplanes
- From Introduction: "The tests described in this report are the first in an investigation by N.A.C.A. of the aerodynamic characteristics of possible tailless arrangements. The investigations will be extended to include whatever range is through most desirable and may include, among other things, variations in aspect ratio, taper, sweepback, washout, air-foil section, dihedral, and also control flaps or other control devices of different forms and proportions."
- The Aerodynamic Wind Vane and the Inherent Stability of Airplanes
- Report discussing the design of the wind vane described rests on the following line of reasoning: An airplane, originally in equilibrium about its C.G. is assumed to be deflected from this position through an angle (delta)i, the variation (delta)i being so sudden that the path of the C.G. and the airplane speed do not change while it is taking place. The aerodynamic forces acting on the wings, tail surfaces, fuselage, etc., which, as a whole, exerted a zero moment (M(sub G) = 0) about the center of gravity at the instant of equilibrium, now exert a moment M(sub G) not equal to 0.
- Aeronautical education and research at the Swiss Institute of Technology in Zurich
- Progress in the scientific and practical fields of aviation has caused the Swiss Institute of Technology to organize lectures and practical training courses in all three branches of aeronautics and to found centers of scientific research, laboratories, etc., in order to supply the government and industries with scientifically and technically trained engineers.
- The Aeronautical Laboratory of the Stockholm Technical Institute
- This report presents a detailed analysis and history of the construction and operation of the aeronautical laboratory of the Stockholm Technical Institute. Engines and balances are discussed and experimental results are also given.
- Agglomeration and Leaching of Slimes and Other Finely Divided Ores
- Report discussing the loads and extracting of slime and other divided ores. The report discusses experimental work done on the materials.
- Agglutinating, Coking, and By-Product Tests of Coals From Pierce County, Washington
- Report discussing testing of coals in Pierce County, Washington. The investigation had three parts: a geological survey of the coal property, washing and crushing tests of the coals, and coking and by-product tests.
- Air conditions close to the ground and the effect on airplane landings
- This report presents the results of an investigation undertaken to determine the feasibility of making glide landings in gusty air. Wind velocities were measured at several stations between the ground and a height of 51 feet, and flight tests were made to determine the actual influence of gusts on an airplane gliding close to the ground.
- Air flow around finned cylinders
- Report presents the results of a study made to determine the air-flow characteristics around finned cylinders. Air-flow distribution is given for a smooth cylinder, for a finned cylinder having several fin spacings and fin widths, and for a cylinder with several types of baffle with various entrance and exit shapes. The results of these tests show: that flow characteristics around a cylinder are not so critical to changes in fin width as they are to fin spacing; that the entrance of the baffle has a marked influence on its efficiency; that properly designed baffles increase the air flow over the rear of the cylinder; and that these tests check those of heat-transfer tests in the choice of the best baffle.
- Air flow in a separating laminar boundary layer
- Report discussing the speed distribution in a laminar boundary layer on the surface of an elliptic cylinder, of major and minor axes 11.78 and 3.98 inches, respectively, has been determined by means of a hot-wire anemometer. The direction of the impinging air stream was parallel to the major axis. Special attention was given to the region of separation and to the exact location of the point of separation. An approximate method, developed by K. Pohlhausen for computing the speed distribution, the thickness of the layer, and the point of separation, is described in detail; and speed-distribution curves calculated by this method are presented for comparison with experiment.
- Air flow in the boundary layer near a plate
- From Summary: "The published data on the distribution of speed near a thin flat plate with sharp leading edge placed parallel to the flow (skin friction plate) are reviewed and the results of some additional measurements are described. The purpose of the experiments was to study the basic phenomena of boundary-layer flow under simple conditions."
- Air Flow in the Boundary Layer of an Elliptic Cylinder
- From Introduction: "The present investigation was carried out for the purpose of supplementing the earlier work with information on the boundary layer under such conditions of air speed and turbulence that transition occurs and the layer is partly laminar and partly turbulent. In the work reported in reference 1, the air speed was about 12 feet per second, and it was assumed that the boundary layer remained in the laminar condition until after separation because the separation point remained fixed and the pressure distribution about the cylinder was unaffected until an air speed of 15 feet per second was reached."
- Air forces and air-force moments at large angles of attack and how they are affected by the shape of the wing
- From Summary: "The present report is, in the first place, a compilation of the test results now available from wing tests up to angles of attack 90^o. Reports are also given of tests with monoplane and auxiliary wings in the Gottingen wind tunnel for the purpose of plotting a steadily rising curve of the normal force as a foundation of the angle of attack."
- Air propellers in yaw
- 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.
- Aircraft Accidents: Method of Analysis
- The revised report includes the chart for the analysis of aircraft accidents, combining consideration of the immediate causes, underlying causes, and results of accidents, as prepared by the special committee, with a number of the definitions clarified. A brief statement of the organization and work of the special committee and of the Committee on Aircraft Accidents; and statistical tables giving a comparison of the types of accidents and causes of accidents in the military services on the one hand and in civil aviation on the other, together with explanations of some of the important differences noted in these tables.
- Aircraft Accidents: Methods of Analysis
- This report is a revision of NACA-TR-357. It was prepared by the Committee on Aircraft Accidents. The purpose of this report is to provide a basis for the classification and comparison of aircraft accidents, both civil and military.
- Aircraft compass characteristics
- From Summary: "A description of the test methods used at the National Bureau of Standards for determining the characteristics of aircraft compasses is given. The methods described are particularly applicable to compasses in which mineral oil is used as the damping liquid. Data on the viscosity and density of certain mineral oils used in United States Navy aircraft compasses are presented. Results of flight tests are presented."
- Aircraft Power-Plant Instruments
- From Summary: "The report includes a description of the commonly used types and some others, the underlying principle utilized in the design, and some design data. The inherent errors of the instrument, the methods of making laboratory tests, descriptions of the test apparatus, and data in considerable detail in the performance of commonly used instruments are presented. Standard instruments and, in cases where it appears to be of interest, those used as secondary standards are described."
- Aircraft rate-of-climb indicators
- From Summary: "The theory of the rate-of-climb indicator is developed in a form adapted for application to the instrument in its present-day form. Certain dynamic effects, including instrument lag, and the use of the rate-of-climb indicator as a statoscope are also considered. Modern instruments are described. A laboratory test procedure is outlined and test results are given."
- Aircraft speed instruments
- From Summary: "This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the Pitot-static air-speed meter which is the standard in the United States for airplanes. A bibliography on air-speed measurement concludes the report."
- Aircraft Woods: Their Properties, Selection, and Characteristics
- From Summary: "This report presents, further, information on the properties of various other native species of wood compared with spruce, and discusses the characteristics of a considerable number of them from the standpoint of their possible application in aircraft manufacture to supplement the woods that are now most commonly used."
- Airfoil Pressure Distribution Investigation in the Variable Density Wind Tunnel
- Report presents the results of wind tunnel tests of pressure distribution measurements over one section each of six airfoils. Pressure distribution diagrams, as well as the integrated characteristics of the airfoils, are given for both a high and a low dynamic scale or, Reynolds number VL/V, for comparison with flight and other wind-tunnel tests, respectively. It is concluded that the scale effect is very important only at angles of attack near the burble.
- Airfoil section characteristics as affected by protuberances
- From Introduction: "The present report deals with another phase of the investigation; that is, the effects on airfoil section characteristics of protuberances extending along the entire span from the airfoil surface."
- Airfoil section characteristics as affected by variations of the Reynolds number
- Report presents the results of an investigation of a systematically chosen representative group of related airfoils conducted in the NACA variable-density wind tunnel over a wide range of Reynolds number extending well into the flight range. The tests were made to provide information from which the variations of airfoil section characteristics with changes in the Reynolds number could be inferred and methods of allowing for these variations in practice could be determined. This work is one phase of an extensive and general airfoil investigation being conducted in the variable-density tunnel and extends the previously published researches concerning airfoil characteristics as affected by variations in airfoil profile determined at a single value of the Reynolds number.
- Airfoil section characteristics as applied to the prediction of air forces and their distribution on wings
- From Introduction: "The system presented herein yields, within the limitations of our present knowledge of aerodynamics, a general solution of the resultant wing forces and moments and their distribution. For the sake of completeness and facility in use, the report contains a table of the important section parameters for many commonly used sections and all other necessary data required to solve the most practical design problems coming within the scope of the system."
- Airfoil section data obtained in the NACA variable-density tunnel as affected by support interference and other corrections
- From Introduction: "The purpose of this report is to present the corrections for application to published results from the variable-density tunnel to give more reliable values of section profile-drag coefficient for airfoils of various thickness."
- An airfoil spanning an open jet
- From Summary: "The first part of the report treats of the theory involved. The second part describes the experiments performed for the purpose of proving the theory."
- Airfoil Theory at Supersonic Speed
- From Summary: "A theory is developed for the airfoil of finite span at supersonic speed analogous to the Prandtl airfoil theory of 1918-1919 for incompressible flow. In addition to the profile and induced drags, account must be taken at supersonic flow of still another drag, namely, the wave drag, which is independent of the wing aspect ratio. Both wave and induced drags are proportional to the square of the lift and depend on the Mach number, that is, the ratio of flight to sound speed. In general, in the case of supersonic flow, the drag-lift ratio is considerably less favorable than is the case for incompressible flow."
- Airplane Flight in the Stratosphere
- This brief survey of the problems encountered in high-altitude flight deals in particular with the need for high lift coefficient in the wings, large aspect ratios in the wings, and also the problem of hermetically sealing the cabin.
- Airplane Landing Gear
- This report presents an investigation of the design and construction of various types of landing gears. Some of the items discussed include: chassises, wheels, shock absorbers (rubber disk and rubber cord), as well as oleopneumatic shock absorbers. Various types of landing gears are also discussed such as the Messier, Bendix, Vickers, and Bleriot.
- Airplane Stability in Taxying
- The stability analysis of an airplane while rolling is much more simplified to the extent that it can be obtained for numerical data which can be put to practical use in the design of landing gear dimensions. Every landing gear type attains to a critical ground friction coefficient that decides the beginning of instability, i.e., nosing over. This study has, in addition, a certain interest for the use of wheel brakes.
- Airship Model Tests in the Variable Density Wind Tunnel
- This report presents the results of wind tunnel tests conducted to determine the aerodynamic characteristics of airship models. Eight Goodyear-Zeppelin airship models were tested in the original closed-throat tunnel. After the tunnel was rebuilt with an open throat a new model was tested, and one of the Goodyear-Zeppelin models was retested. The results indicate that much may be done to determine the drag of airships from evaluations of the pressure and skin-frictional drags on models tested at large Reynolds number.
- The Airspeed "Courier" Commercial Airplane (British): A Low-Wing Cantilever Monoplane
- Circular presenting a description of the first British airplane with a retractable landing gear, which is a small and aerodynamically clean monoplane. A description of the design and flight characteristics is provided.
- The Airspeed "Oxford" Training Airplane (British): A Two-Engine Cantilever Monoplane
- Circular describing the Airspeed A.S. 10 "Oxford", which is a twin-engine trainer with a variety of equipment, including propellers, landing gear, and other components.Details of the wings, fuselage, the inside, characteristics, performance, drawings, and photographs are provided.
- Alaska-Yukon Caribou
- Brief summary of the physical characteristics, general habits, breeding habits, food habits, migratory habits, and habitat of the Alaska-Yukon caribou.
- Alterations and Tests of The "Farnboro" Engine Indicator
- "The 'Farnboro' electric indicator was tested as received from the manufacturers, and modifications made to the instrument to improve its operation. The original design of disk valve was altered so as to reduce the mass, travel, and seat area. Changes were made to the recording mechanism, which included a new method of locating the top center position on the record. The effect of friction on the motion of the pointer while taking motoring and power cards was eliminated by providing a means of putting pressure lines on the record" (p. 1).
- Alternating-current equipment for the measurement of fluctuations of air speed in turbulent flow
- From Summary: "Recent electrical and mechanical improvements have been made in the equipment developed at the National Bureau of Standards for measurement of fluctuations of air speed in turbulent flow. Data useful in the design of similar equipment are presented. The design of rectified alternating-current power supplies for such apparatus is treated briefly, and the effect of the power supplies on the performance of the equipment is discussed."
- Altitude-pressure tables based on the United States standard atmosphere
- This report is a revision of the altitude pressure tables of the United States standard atmosphere given in Technical Report No. 246 and the altitude range has been extended from 50,000 to 80,000 feet.
- The Amiot 140 M Military Airplane (French): An All-Metal Multiplace High-Wing Monoplane
- Circular presenting the Amiot 140 M, which is the first of a series of airplanes that have been developed by a French aircraft manufacturer. A description of the design, dimensions, flight characteristics, blueprints, and photographs are provided.
- Analyses of Crude Oils From Some Fields of Southern Louisiana
- Report issued by the U.S. Bureau of Mines on the studies of crude oil samples collected from southern Louisiana. The properties of each sample are analyzed. This report includes tables.
- Analysis and Model Tests of Autogiro Jump Take-Off
- 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."
- Analysis of 2-Spar Cantilever Wings With Special Reference to Torsion and Load Transference
- "This paper deals with the analysis of 2-spar cantilever wings in torsion, taking cognizance of the fact that the spars are not independent, but are interconnected by ribs and other structural members. The principles of interaction are briefly explained, showing that the mutual relief action occurring depends on the "pure torsional stiffness" of the wing cross section. Various practical methods of analysis are outlined" (p. 45).
- Analysis of a Strut With a Single Elastic Support in the Span, With Applications to the Design of Airplane Jury-Strut Systems
- Report presenting an analysis of a wing brace with a small auxiliary strut, which is attached to the wing spar at the upper end. The design is quite effective but has some difficult analysis problems. The report is broken into two parts; one is a theoretical investigation and one is an experimental investigation.
- An Analysis of Lateral Stability in Power-Off Flight With Charts for Use in Design
- "The aerodynamic and mass factors governing lateral stability are discussed and formulas are given for their estimation. Relatively simple relationships between the governing factors and the resulting stability characteristics are presented. A series of charts is included with which approximate stability characteristics may be rapidly estimated" (p. 1).