National Advisory Committee for Aeronautics (NACA) - 81 Matching Results

Search Results

The aerodynamic properties of thick aerofoils suitable for internal bracing

Description: From Introduction: "The object of this investigation was to determine the characteristics of various types of wings having sufficient depth to entirely inclose the wing bracing, and also to provide data for the further design of such sections. Results of the investigation of the following subjects are given: (1) effect of changing the upper and lower camber of thick aerofoils of uniform section; (2) effect of thickening the center and thinning the tips of a thin aerofoil; (3) effect of adding a convex lower surface to a tapered section; (4) effect of changing the mean thickness with constant center and tip sections; and (5) effect of varying the chord along the span."
Date: 1920
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department

Airplane performance as influenced by the use of a supercharged engine

Description: The question of the influence of a supercharged engine on airplane performance is treated here in a first approximation, but one that gives an exact idea of the advantage of supercharging. Considered here is an airplane that climbs first with an ordinary engine, not supercharged, and afterwards climbs with a supercharged engine. The aim is to find the difference of the ceilings reached in the two cases. In the case of our figure, the ceiling from 25,000 feet is increased to 37,000 feet, the supercharging maintaining the power only up to 20,000 feet. This makes, in comparison with an engine without supercharging, an increase of about 50 percent.
Date: May 1920
Creator: De Bothezat, George
Partner: UNT Libraries Government Documents Department

Aluminum and its light alloys

Description: Report is a summary of research work which has been done here and abroad on the constitution and mechanical properties of the various alloy systems with aluminum.
Date: 1920?~
Creator: Merica, Paul D
Partner: UNT Libraries Government Documents Department

Annual report of the National Advisory Committee for Aeronautics (4th).administrative report including Technical Reports nos. 24 to 50

Description: Report includes the National Advisory Committee for Aeronautics letter of submittal to the President, Congressional report, summaries of the committee's activities and research accomplished, expenditures, problems, recommendations, and a compilation of technical reports produced.
Date: 1920
Partner: UNT Libraries Government Documents Department

Annual report of the National Advisory Committee for Aeronautics (5th).administrative report including Technical Reports nos. 51 to 82

Description: Report includes the National Advisory Committee for Aeronautics letter of submittal to the President, Congressional report, summaries of the committee's activities and research accomplished, expenditures, and a compilation of technical reports produced.
Date: 1920
Partner: UNT Libraries Government Documents Department

Bomb trajectories

Description: The report is a mathematical treatise dealing with the trajectories of bombs of high terminal velocity, dropped from a great altitude.
Date: January 1, 1920
Creator: Wilson, Edwin Bidwell
Partner: UNT Libraries Government Documents Department

Calculation of low-pressure indicator diagrams

Description: Report develops a fundamental conception and partial application of a method for calculating the pressure-volume relationships to be expected for any given engine design. It outlines a method of computing and interpreting low-pressure indicator cards.
Date: January 1, 1920
Creator: Kemble, E C
Partner: UNT Libraries Government Documents Department

Carbureting conditions characteristics of aircraft engines

Description: Tests were conducted at the altitude laboratory erected at the Bureau of Standards for the National Advisory Committee for Aeronautics to determine the changes in engine performance with changes in atmospheric temperature and pressure at various levels above the earth's surface, with special reference to (a) the variables affecting the functioning of the carburetor and (b) the changes in performance resulting from variables in the carburetor itself. This report constitutes a concise statement of the difficulties to be encountered in this branch of carburetion.
Date: January 1, 1920
Creator: Tice, Percival S
Partner: UNT Libraries Government Documents Department

Characteristics of high-tension magnetos

Description: This report gives the results of an investigation made into the fundamental physical characteristics of high-tension ignition magnetos, and also describes the methods used for measuring the quantities involved.
Date: January 1, 1920
Creator: Silsbee, F. B.
Partner: UNT Libraries Government Documents Department

Design of recording wind tunnel balances

Description: Given here is a description of the design of a scientific recording wind tunnel balance. It was decided that the most satisfactory arrangement would be a rigid ring completely surrounding the tunnel or wind stream, so that the model could be supported from it by wires or any arrangement of spindles. The forces and moments acting on this ring can then be recorded by suitable weighing apparatus. The methods available for recording forces on the arms are explained. The proposed type of balance will support the model rigidly in a variety of ways, will make a complete test without attention, and will plot the results so that all computations are avoided.
Date: December 1, 1920
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department

Development of air speed nozzles

Description: Report describes the development of a suitable speed nozzle for the first few thousand airplanes made by the United States during the recent war in Europe, and to furnish a basis for more mature instruments in the future. Requirements for the project were to provide a suitable pressure collector for aircraft speed meters and to develop a speed nozzle which would be waterproof, powerful, unaffected by slight pitch and yaw, rugged and easy to manufacture, and uniform in structure and reading, so as not to require individual calibration.
Date: January 1, 1920
Creator: Zahm, A F
Partner: UNT Libraries Government Documents Department

Drag or negative traction of geared-down supporting propellers in the downward vertical glide of a helicopter

Description: Discussed here are computations of drag or negative traction of geared down supporting propellers in the downward vertical glide of a helicopter. By means of Frounde's Theory, the maximum value of the drag of a windmill is calculated. For wooden propellers, the author finds that the difference between the drag and the weight is proportional to the number of blades and is larger for propellers of small diameter; thus it is 25 kg. for a six blade propeller with a diameter of 2 m. 50. The author notes that if we are to adopt large propellers, we must have recourse to a different method of construction, resulting in large dimension propellers much lighter than those made of wood. In discussing insufficient drag, the author notes that the question of the drag of geared down supporting propellers can only be decided by experiment.
Date: September 1, 1920
Creator: Toussaint, A
Partner: UNT Libraries Government Documents Department

Duralumin

Description: The use of duralumin in the construction of aircraft makes an account of the properties of this material desirable especially with reference to its working qualities as developed by experience.
Date: July 1, 1920
Creator: Unger, E & Schmidt, E
Partner: UNT Libraries Government Documents Department

The dynamometer hub

Description: The construction of the dynamometer hub is illustrated and explained, and its electrical and aviation motor tests, as well as those in free flight, described.
Date: September 1, 1920
Creator: Stieber, W
Partner: UNT Libraries Government Documents Department

Effect of altitude on radiator performance

Description: As an airplane rises to high altitudes the decrease in the density and the temperature of the air have important effects on the performance of the radiator. This report gives the results of a study of the effect of reduced pressure and temperature upon the capacity of airplane radiators. A method is presented by which the performance of a radiator at an altitude may be estimated for a particular speed of the airplane at a particular altitude.
Date: January 1, 1920
Creator: James, W S & Parsons, S R
Partner: UNT Libraries Government Documents Department

Experience with geared propeller drives for aviation engines

Description: I. The development of the gear wheels: (a) bending stresses; (b) compressive stresses; (c) heating; (d) precision of manufacture. II. General arrangement of the gearing. III. Vibration in the shaft transmission. An overview is given of experience with geared propeller drives for aviation engines. The development of gear wheels is discussed with emphasis upon bending stresses, compressive stresses, heating, and precision in manufacturing. With respect to the general arrangement of gear drives for airplanes, some principal rules of mechanical engineering that apply with special force are noted. The primary vibrations in the shaft transmission are discussed. With respect to vibration, various methods for computing vibration frequency and the influence of elastic couplings are discussed.
Date: September 1, 1920
Creator: Kutzbach, K
Partner: UNT Libraries Government Documents Department

Experimental research on air propellers II

Description: This report is a continuation of NACA Technical Report 14. It presents the results of an experimental investigation on the performance of air propellers which was divided into five parts, as follows: (1) Tests under conditions of flight on 16 model propellers of different forms, sections, or pitch ratios from those of Technical Report 14; (2) Tests under conditions of flight on one model propeller of variable pitch; (3) Tests under conditions of flight on three sets of right and left hand model propellers in series; (4) Tests on 12 model propellers to determine brake effect or negative thrust at negative slip; (5) Standing thrust and power tests of 67 model propellers.
Date: January 1, 1920
Creator: Durand, William F & Lesley, E P
Partner: UNT Libraries Government Documents Department

Experimental research on air propellers III

Description: Report presents the results of wind tunnel tests of propellers that examined the influence of the following characteristics: (1) nominal pitch ratio 1.3 combined with a certain number of the more common or standard forms and proportions; (2) driving face slightly rounded or convex; (3) change in the location of the maximum thickness ordinate of the blade section; (4) pushing forward the leading edge of the blade, thus giving a rounded convex surface on the leading side of the driving face. (5) a series of values for the constant "angle of attack" in forming propellers with radially increasing pitch. In accordance with these purposes tests were carried out on 28 propellers.
Date: January 1, 1920
Creator: Durand, W F & Lesley, E P
Partner: UNT Libraries Government Documents Department