You limited your search to:

  Partner: UNT Libraries Government Documents Department
 Decade: 1920-1929
 Collection: National Advisory Committee for Aeronautics Collection
Micarta Propellers II : method of construction

Micarta Propellers II : method of construction

Date: August 1, 1924
Creator: Caldwell, F W
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
The simplifying assumptions, reducing the strict application of classical hydrodynamics to practical aeronautical computations

The simplifying assumptions, reducing the strict application of classical hydrodynamics to practical aeronautical computations

Date: November 1, 1924
Creator: Munk, Max M
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Wind tunnel tests of fuselages and windshields

Wind tunnel tests of fuselages and windshields

Date: September 1, 1925
Creator: Warner, Edward P
Description: The tests described herein were made in 1918, in the old four-foot wind tunnel at the Massachusetts Institute of Technology and at the request of the Engineering Division of the U.S. Army Air Service. The results were given circulation only in official circles at that time. The interest of the work appears sufficient to justify its wider distribution even at this very late date.
Contributing Partner: UNT Libraries Government Documents Department
Some tables of the factor of apparent additional mass

Some tables of the factor of apparent additional mass

Date: July 1, 1924
Creator: Munk, Max M
Description: 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.
Contributing Partner: UNT Libraries Government Documents Department
Propeller scale effect and body interference

Propeller scale effect and body interference

Date: September 1, 1925
Creator: Weick, Fred E
Description: This note shows that the main part of the discrepancy between full flight propeller performance and the performance of models in a wind tunnel is due to a scale effect, and that a minor part is caused by body interference. Analyses are made of propeller performances on several standard airplanes, and the actual brake horsepower compared with the power as calculated from model test data. The calculated power is based on that absorbed by a wind tunnel propeller model which is geometrically similar to the full scale propeller and is operating under the same ratio of V/nD.
Contributing Partner: UNT Libraries Government Documents Department
Model supports and their effects on the results of wind tunnel tests

Model supports and their effects on the results of wind tunnel tests

Date: February 1, 1923
Creator: Bacon, David L
Description: The airflow about a model while being tested is often sufficiently affected by the model support to lead to erroneous conclusions unless appropriate corrections are used. In this paper some new material on the subject is presented, together with a review of the airfoil support corrections used in several other laboratories.
Contributing Partner: UNT Libraries Government Documents Department
Tests on an airplane model, AEG D I of the Allgemeine Elektricitats Gesellschft, A-G, airplane construction section conducted at the Gottingen Model Testing Laboratory for Aerodynamics

Tests on an airplane model, AEG D I of the Allgemeine Elektricitats Gesellschft, A-G, airplane construction section conducted at the Gottingen Model Testing Laboratory for Aerodynamics

Date: February 1, 1923
Creator: Munk, Max
Description: Tests were carried out in the small wind tunnel of the Gottingen establishment on a complete model of the AEG D I airplane. The agreement between the model and the complete airplane applies particularly to the wings, which have ribs cut out of sheet metal and built up in exactly the same manner as in the actual airplane. Various series of tests were carried out with this model in which one or the other of the control surfaces were adjusted to various angles, while the others remained in their neutral positions. During the first three series of tests, the stabilizer was set at a positive angle of 3 degrees, 45' relative to the axis of the engine crankshaft, after which further tests at a 6 degree 30' we made. Finally, the model was tested with the tail group removed. With the elevators set in the prescribed positions, the lift, the drag, and the moments about an axis passing through the center of gravity and perpendicular to the plane of symmetry were measured. All three sets of readings are given as absolute coefficients. Where one of the other control surfaces was deflected from its normal position, the moment produced by that ...
Contributing Partner: UNT Libraries Government Documents Department
The air propeller, its strength and correct shape

The air propeller, its strength and correct shape

Date: February 1, 1923
Creator: Dietsius, H
Description: It is possible to give a propeller such a shape that, under given conditions, viz., a definite speed of revolution and flying speed, the bending stresses in the blades will assume quite an insignificant magnitude.
Contributing Partner: UNT Libraries Government Documents Department
Determination of climbing ability

Determination of climbing ability

Date: February 1, 1923
Creator: Blasius, H
Description: The vertical distribution of the pressure, temperature, and density of the atmosphere varies from day to day. Thus, rates of climb on different days cannot be compared directly, but must be corrected with reference to a standard rate of diminution of air density with increasing altitude. The following problem, therefore, has to be solved. An airplane has climbed on a certain day under prevailing atmospheric conditions as shown by the barograph. How would the same airplane climb in a standard atmosphere? This problem has already been dealt with by Everling, using the monthly and yearly mean of the vertical temperature distribution. Von Mises solved the problem by arithmetical methods. Here, conditions are examined which shorten or lengthen the climbing time. In establishing the corrected barogram, computation seems more practical than graphical treatment. The basis of the answer to the question answered here is summed up in the remark that lift, drag, propeller thrust, and torque and engine power depend only on the density of the air and do not change with the pressure and temperature, provided that the density remains constant.
Contributing Partner: UNT Libraries Government Documents Department
Wind tunnel tests of five strut sections in yaw

Wind tunnel tests of five strut sections in yaw

Date: November 1, 1923
Creator: Warner, Edward P
Description: In the first series of wind tunnel tests, the drag and cross wing force of all the struts were measured at a wind speed of 30 mph and at angles of yaw from 0 degrees to 20 degrees. To determine the magnitude of the VL effect, each strut was tested at zero yaw and at a series of speeds ranging from 15 to 38 mph. Although designed as fairings for cables, part of these sections gave such high crosswind forces that they seemed to have possibilities as airfoils. Therefore, the lift (identical with the crosswind force) and drag coefficients were recalculated for four sections on the basis of broadside area to make them comparable with wing coefficients. The general conclusion that the best fineness ratio for a strut is a function of the Reynolds number, decreasing steadily as that quality increases, has of course been reached many times, both by theory and experiment. It was confirmed here once more, and the effect of form on sensitiveness to VL is also strikingly shown. It seems probable that this effect of form is largely due to interaction between the nose and tail, and to the influence which the form of the nose ...
Contributing Partner: UNT Libraries Government Documents Department