Technical Report Archive and Image Library (TRAIL) - 143 Matching Results

Search Results

Additional test data on static longitudinal stability

Description: From Summary: "The purpose of this investigation was to explore the influence of weights of the controls on the stability with elevator released. The available test data were extended to stability with elevator locked. In this connection the study of the propeller effect seemed of vital importance."
Date: August 1934
Creator: Hubner, Walter
Partner: UNT Libraries Government Documents Department

An aerodynamic analysis of the autogiro rotor with a comparison between calculated and experimental results

Description: This report presents an extension of the autogiro theory of Glauert and Lock in which the influence of a pitch varying with the blade radius is evaluated and methods of approximating the effect of blade tip losses and the influence of reversed velocities on the retreating blades are developed. A comparison of calculated and experimental results showed that most of the rotor characteristics could be calculated with reasonable accuracy, and that the type of induced flow assumed has a secondary effect upon the net rotor forces, although the flapping motion is influenced appreciably. An approximate evaluation of the effect of parasite drag on the rotor blades established the importance of including this factor in the analysis.
Date: 1934
Creator: Wheatley, John B
Partner: UNT Libraries Government Documents Department

The aerodynamic analysis of the gyroplane rotating-wing system

Description: From Summary: "An aerodynamic analysis of the gyroplane rotating-wing system is presented herein. This system consists of a freely rotating rotor in which opposite blades are rigidly connected and allowed to rotate or feather freely about their span axis. Equations have been derived for the lift, the lift-drag ratio, the angle of attack, the feathering angles, and the rolling and pitching moments of a gyroplane rotor in terms of its basic parameters. Curves of lift-drag ratio against lift coefficient have been calculated for a typical case, showing the effect of varying the pitch angle, the solidarity, and the average blade-section drag coefficient. The analysis expresses satisfactorily the qualitative relations between the rotor characteristics and the rotor parameters. As disclosed by this investigation, the aerodynamic principles of the gyroplane are sound, and further research on this wing system is justified."
Date: March 1934
Creator: Wheatley, John B
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of anemometer cups

Description: From Introduction: "The investigation was intended to cover the characteristics of individual cups and of similar cups mounted on complete cup wheals. This report treats the static tests run on the individual cups."
Date: February 1934
Creator: Brevoort, M J & Joyner, U T
Partner: UNT Libraries Government Documents Department

Aerodynamic effects of a split flap on the spinning characteristics of a monoplane model

Description: From Summary: "The investigation described in this report was made to determine the change in aerodynamic forces and moments produced by split flaps in a steady spin. The test were made with the spinning balance in the NACA 5-foot vertical wind tunnel. A low-wing monoplane model was tested with and without the split flaps in 12 spinning attitudes chosen to cover the probable spinning range. The results obtained indicate that the use of split flaps on an airplane is unlikely, in any case, to have much beneficial effect on a spin, and it might make the spin dangerous."
Date: December 1934
Creator: Bamber, M J
Partner: UNT Libraries Government Documents Department

The aerodynamic effects of wing cut-outs

Description: From Introduction: "The information now available concerning wing cut-outs or applicable to the analysis of their effects is plentiful (references 1 to 7) but too disconnected and unorganized to be of the greatest possible usefulness. In connection with the interference program being conducted in the N.A.C.A. varible-density wind tunnel, an analysis was therefore made of existing material to determine the qualitative effects of the different features of wing cut-outs, and to obtain means of calculating wing characteristics as affected by them."
Date: 1934
Creator: Sherman, Albert
Partner: UNT Libraries Government Documents Department

Aerodynamic principles of the direct lifting propeller

Description: 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."
Date: January 1934
Creator: Schrenk, Martin
Partner: UNT Libraries Government Documents Department

Aerodynamic rolling and yawing moments produced by floating wing-tip ailerons, as measured by spinning balance

Description: 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."
Date: March 1934
Creator: Bamber, Millard J
Partner: UNT Libraries Government Documents Department

Air conditions close to the ground and the effect on airplane landings

Description: 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.
Date: April 3, 1934
Creator: Thompson, F L; Peck, W C & Beard, A P
Partner: UNT Libraries Government Documents Department

Air flow in a separating laminar boundary layer

Description: 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.
Date: December 1, 1934
Creator: Schubauer, G. B.
Partner: UNT Libraries Government Documents Department

Aircraft power-plant instruments

Description: 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."
Date: January 1, 1934
Creator: Sontag, Harcourt & Brombacher, W. G.
Partner: UNT Libraries Government Documents Department

Analysis of spinning in a monoplane wing by the induction method as compared with the strip method

Description: The problem of autorotation has been attacked by various authors, in particular Fuchs and Schmidt who applied the so-called strip method which is based upon the assumption that the forces and moments per unit length acting in each section of the wing are equal to those on an infinite cylindrical wing of equal section in an air flow of intensity and direction resulting from the apparent relative motion of this section with respect to the surrounding air. In other words they disregarded the induced velocities, which, however, are of such importance that their omission is bound to result in appreciable errors, as we attempt to prove in this report.
Date: June 1, 1934
Creator: Poggi, L
Partner: UNT Libraries Government Documents Department

Applied Methods and Equipment for Reducing Evaporation Losses of Petroleum and Gasoline

Description: From Scope of Report: "The subject matter in this bulletin is divided as follows: Theory of evaporation; methods of determining evaporation losses; lease operation; transportation and storage of crude petroleum; and evaporation losses of gasoline at the refineries."
Date: 1934
Creator: Schmidt, Ludwig
Partner: UNT Libraries Government Documents Department

The behavior under shearing stress of duralumin strip with round, flanged holes

Description: This report presents the results of an investigation to determine the behavior of dural strip with flanged holes in the center when subjected to shear stresses. They buckle under a certain load just as a flat sheet. There is one optimum hole spacing and a corresponding buckling load in shear for each sheet width, sheet thickness, and flange form. Comparison with non-flanged sheets revealed a marked increase of buckling load in shear due to the flanging and a slightly greater displacement. Strips were clamped between two stationary end rails and one sliding center rail at which the shear is applied. The force was measured with a tension stirrup up to 20 tons and a compression dynamometer up to 10 tons. The displacement was recorded with the Zeiss dial gauge. The following were investigated: 1) effect of strip width; 2) strip thickness; 3) diameter of flanging; 4) depth of flanging; 5) and hole distance.
Date: October 1, 1934
Creator: Schussler, Karl
Partner: UNT Libraries Government Documents Department