Airfoil section characteristics as affected by protuberances (open access)

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."
Date: July 11, 1932
Creator: Jacobs, Eastman N.
System: The UNT Digital Library
Calculation of Potential Flow Past Airship Bodies in Yaw (open access)

Calculation of Potential Flow Past Airship Bodies in Yaw

An outline of Von Karman's method of computing the potential flow of airships in yaw by means of partially constant dipolar superposition on the axis of the body is followed by several considerations for beginning and end of the superposition. Then this method is improved by postulating a continuous, in part linearly variable dipolar superposition on the axis. The second main part of the report brings the calculation of the potential flow by means of sources and sinks, arranged on the surface of the airship body.
Date: July 1932
Creator: Lotz, I.
System: The UNT Digital Library
Comparative Performance of a Powerplus Vane-Type Supercharger and an N.A.C.A. Roots-Type Supercharger (open access)

Comparative Performance of a Powerplus Vane-Type Supercharger and an N.A.C.A. Roots-Type Supercharger

"This report presents the results of tests of a Powerplus supercharger and a comparison of its performance with the performance previously obtained with an N.A.C.A. Roots-type supercharger. The Powerplus supercharger is a positive displacement blower of the vane type having mechanically operated vanes, the movement of which is controlled by slots and eccentrics. The supercharger was tested at a range of pressure differences from 0 to 15 inches of mercury and at speeds from 500 to 2,500 r.p.m." (p. 1).
Date: July 1932
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
System: The UNT Digital Library
Effect of Length of Handley Page Tip Slots on the Lateral-Stability Factor, Damping in Roll (open access)

Effect of Length of Handley Page Tip Slots on the Lateral-Stability Factor, Damping in Roll

"Tests have been made in the NACA 7 by 10 foot wind tunnel on a Clark Y wing model equipped with various lengths of Handley Page slots extending inward from the wing tips. The slot lengths tested ranged from 20 to 100 per cent of the semi span. The effect of slot lengths on damping in roll was determined by means of both free-autorotation and forced-rotation test. In addition, the maximum lift coefficient was found with each slot length. The optimum length of slot for satisfactory damping in roll over a large range of angles of attack was found to be slightly over 50 per cent of the semispan for the form of slot tested" (p. 1).
Date: July 1932
Creator: Weick, Fred E. & Wenzinger, Carl J.
System: The UNT Digital Library
The Farman Night Bombers 211 and 212 (French): Four-Engine High-Wing Monoplanes (open access)

The Farman Night Bombers 211 and 212 (French): Four-Engine High-Wing Monoplanes

Circular presenting a description of the Farman night bombers 211 and 212, which are four-engine high-wing monoplanes that are equipped with different engines. Details of the wing structure, fuselage, tail surface and controls, landing gear, power plant, characteristics, performance, drawings, and photographs are provided.
Date: July 1932
Creator: unknown
System: The UNT Digital Library
Increase in the Maximum Lift of an Airplane Wing Due to a Sudden Increase in Its Effective Angle of Attack Resulting From a Gust (open access)

Increase in the Maximum Lift of an Airplane Wing Due to a Sudden Increase in Its Effective Angle of Attack Resulting From a Gust

Wind-tunnel tests are described, in which the angle of attack of a wing model was suddenly increased (producing the effect of a vertical gust) and the resulting forces were measured. It was found that the maximum lift coefficient increases in proportion to the rate of increase in the angle of attack. This fact is important for the determination of the gust stresses of airplanes with low wing loading. The results of the calculation of the corrective factor are given for a high-performance glider and a light sport plane of conventional type.
Date: July 1932
Creator: Kramer, Max
System: The UNT Digital Library
Methods of Visually Determining the Air Flow Around Airplanes (open access)

Methods of Visually Determining the Air Flow Around Airplanes

"This report describes methods used by the National Advisory Committee for Aeronautics to study visually the air flow around airplanes. The use of streamers, oil and exhaust gas streaks, lampblack and kerosene, powdered materials, and kerosene smoke is briefly described. The generation and distribution of smoke from candles and from titanium tetrachloride are described in greater detail because they appear most advantageous for general application. Examples are included showing results of the various methods" (p. 1).
Date: July 1932
Creator: Gough, Melvin N. & Johnson, Ernest
System: The UNT Digital Library
Preliminary photomicrographic studies of fuel sprays (open access)

Preliminary photomicrographic studies of fuel sprays

Photomicrographs were taken of fuel sprays injected into air at various densities for the purpose of studying the spray structure and the stages in the atomization of the fuel. The photomicrographs were taken at magnifying powers of 2.5, 3.25, and 10, using a spark discharge of very short duration for illumination. The results indicate that the theory advanced by Dr. R. A. Castleman, Jr., on the atomization of fuel in carburetors may also be applied to the atomization of fuel sprays of the solid-injection type. The fuel leaves the nozzle as a solid column, is ruffled and then torn into small, irregular ligaments by the action of the air. These ligaments are then quickly broken up into drops by the surface tension of the fuel. The photomicrographs also show that the dispersion of a fuel spray at a given distance from the nozzle increases with an increase in the jet velocity or an increase in the air density. The first portions of fuel sprays injected from an automatic injection valve into air at atmospheric density have a much greater dispersion than the later portions, but this difference decreases rapidly as the air density is increased.
Date: July 1932
Creator: Lee, Dana W. & Spencer, Robert C.
System: The UNT Digital Library
Stresses Developed in Seaplanes While Taking Off and Landing (open access)

Stresses Developed in Seaplanes While Taking Off and Landing

In the case of seaplanes, the lack of elastic shock absorbers, the presence of which might be quite dangerous, especially in taking off, makes it necessary to give some consideration to the phenomenon of landing. Special consideration must be given the process of taking off, since even moderately rough water may develop rather large stresses. The purpose of this communication is to show what has been accomplished in Italy and other countries and to draw a few useful conclusions.
Date: July 1932
Creator: Verduzio, Rudolfo
System: The UNT Digital Library
Towing Tests of Models as an Aid in the Design of Seaplanes (open access)

Towing Tests of Models as an Aid in the Design of Seaplanes

This report concerns the making and evaluation of a towing test of a seaplane float system. Some of the topics considered are: 1) the influence of the wing cell and power plant on the take-off performance; 2) the determination of the resistance curve for the take-off free to trim; 3) the resistance curves with elevator control (at fixed trims); 4) take-off time and take-off run.
Date: July 1932
Creator: Schröder, P.
System: The UNT Digital Library
Wind-tunnel research comparing lateral control devices, particularly at high angles of attack 6: skewed ailerons on rectangular wings (open access)

Wind-tunnel research comparing lateral control devices, particularly at high angles of attack 6: skewed ailerons on rectangular wings

"This report covers the sixth of a series of investigations in which various lateral control devices are compared with particular reference to their effectiveness at high angles of attack. The present report deals with flap-type ailerons hinged about axes having an angle with respect to the leading and trailing edges of the wing. Tests were made on four different skewed ailerons, including two different angles of skew and two sizes of ailerons" (p. 81).
Date: July 12, 1932
Creator: Weick, Fred E. & Harris, Thomas A.
System: The UNT Digital Library
Working Charts for the Determination of the Lift Distribution Between Biplane Wings (open access)

Working Charts for the Determination of the Lift Distribution Between Biplane Wings

"In this report are presented empirical working charts from which the distribution of lift between wings, that is the fraction of the total lift borne by each, can be determined in the positive lift range for any ordinary biplane cellule whose individual wings have the same profile. The variables taken directly into account include airfoil section, stagger, gap/chord ratio, decalage, chord ratio, and overhang. It is shown that the influence of unequal sweepback and unequal dihedral in upper and lower wings may be properly provided for by utilizing the concepts of average stagger and average gap/chord ratio, respectively" (p. 93).
Date: July 11, 1932
Creator: Kuhn, Paul
System: The UNT Digital Library