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Simplified Propeller Design for Low-Powered Airplanes

Description: "The object of this report is to furnish the designer and builder of small airplanes a simple system for designing the propeller and making the drawing. An empirical design method is used, based on tests of model propellers in a wind tunnel and full scale tests of propellers in flight. The actual designing is accomplished by means of charts and involves very little calculation" (p. 1).
Date: January 1925
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Propeller Design: Extension of Test Data on a Family of Model Propellers by Means of the Modified Blade Element Theory 2

Description: This report is the second of a series of four on propeller design, and describes the method used to extend the data obtained from tests on a family of thirteen model propellers to include all propellers of the same form likely to be met in practice. This necessitates the development of a method of propeller analysis which when used to calculate the powers and efficiencies gives results which check the tests throughout their range.
Date: May 1926
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Propeller Scale Effect and Body Interference

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" (p. 1).
Date: September 1925
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Propeller Design 4: A Simple Method for Determining the Strength of Propellers

Description: "The object of this report, the last of a series of four on propeller design, is to describe a simple method for determining whether the strength of a propeller of a standard form is sufficient for safe operation. An approximate method of stress analysis is also given" (p. 1).
Date: June 1926
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Propeller Design: Practical Application of the Blade Element Theory 1

Description: "This report is the first of a series of four on propeller design and contains a description of the blade elements or modified Drzewiecke theory as used in the Bureau of Aeronautics, U.S. Navy Department. Blade interference corrections are used which were taken from R.& M. NO. 639 of the British Advisory Committee for Aeronautics. The airfoil characteristics used were obtained from tests of model propellers, not from tests of model wings" (p. 1).
Date: May 1926
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Full Scale Drag Tests on Various Parts of Sperry Messenger Airplane

Description: "The drag of a Sperry Messenger airplane with the wings removed, and also the drag of its various component parts, was measured in the 20-foot air stream of the N.A.C.A. propeller research tunnel at air speeds from 50 to 100 m.p.h. It was found that the three-cylinder radial air-cooled engine nearly doubled the drag of the bare fuselage, and the drag of the landing gear was about the same as that of the fuselage and engine combined" (p. 1).
Date: January 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Study of Open Jet Wind Tunnel Cones

Description: "Tests have been made by the National Advisory Committee for Aeronautics on the air flow in an open jet wind tunnel with various sizes, shapes, and spacings of cones, and the flow studied by means of velocity and direction surveys in conjunction with flow pictures. It was found that for all combinations of cones tested the flow is essentially the same, consisting of an inner core of decreasing diameter having uniform velocity and direction, and a boundary layer of more or less turbulent air increasing in thickness with length of jet. The energy ratio of the tunnel was obtained for the different combinations of cones, and the spilling around the exit cone causing undesirable air currents in the experiment chamber was noted" (p. 1).
Date: August 1927
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

The effect of the wings of single engine airplanes on propulsive efficiency as shown by full scale wind tunnel tests

Description: An investigation was conducted to determine the effect of the wings on propulsive efficiency. The wings are shown to cause a reduction of 1 percent to 3 percent in propulsive efficiency, which is about the same for monoplane as well as biplane wings.
Date: October 1929
Creator: Weick, Fred E. & Wood, Donald H.
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics of a model wing having a split flap deflected downward and moved to the rear

Description: From Summary: "Tests were made on a model wing with three different sized split trailing-edged flaps, in the NACA 7 by 10 foot wind tunnel. The flaps were formed of the lower rear portion of the wing and were rotated downward about axes at their front edges. The lift, drag, and center of pressure were measured with the axis in its original position and also with it moved back in even steps to the trailing edge of the main wing, giving in effect an increase in area. The split flaps when deflected about their original axis locations gave slightly higher maximum lift coefficients than conventional trailing-edge flaps, and the lift coefficients were increased still further by moving the axes toward the rear. The highest value of C(sub L max), which was obtained with the largest flap hinged at 90 per cent of the chord from the leading edge, was 2.52 as compared with 1.27 for the basic wing."
Date: May 1932
Creator: Weick, Fred E. & Harris, Thomas E.
Partner: UNT Libraries Government Documents Department

Wind tunnel research comparing lateral control devices, particularly at high angles of attack 11: various floating tip ailerons on both rectangular and tapered wings

Description: Discussed here are a series of systematic tests being conducted to compare different lateral control devices with particular reference to their effectiveness at high angles of attack. The present tests were made with six different forms of floating tip ailerons of symmetrical section. The tests showed the effect of the various ailerons on the general performance characteristics of the wing, and on the lateral controllability and stability characteristics. In addition, the hinge moments were measured for the most interesting cases.
Date: May 1933
Creator: Weick, Fred E. & Harris, Thomas A.
Partner: UNT Libraries Government Documents Department

Wind-tunnel tests of the Fowler variable-area wing

Description: The lift, drag, and center of pressure characteristics of a model of the Fowler variable-area wing were measured in the NACA 7 by 10 foot wind tunnel. The Fowler wing consists of a combination of a main wing and an extension surface, also of airfoil section. The extension surface can be entirely retracted within the lower rear portion of the main wing or it can be moved to the rear and downward. The tests were made with the nose of the extension airfoil in various positions near the trailing edge of the main wing and with the surface at various angular deflections. The highest lift coefficient obtained was C(sub L) = 3.17 as compared with 1.27 for the main wing alone.
Date: May 1932
Creator: Weick, Fred E. & Platt, Robert C.
Partner: UNT Libraries Government Documents Department

Aerodynamic tests of a low aspect ratio tapered wing with various flaps, for use on tailless airplanes

Description: 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."
Date: June 1933
Creator: Weick, Fred E. & Sanders, Robert
Partner: UNT Libraries Government Documents Department

Wind tunnel research comparing lateral control devices, particularly at high angles of attack 10: various control devices on a wing with a fixed auxiliary airfoil

Description: Results are given of a series of systemic tests comparing lateral control devices with particular reference to their effectiveness at high angles of attack. These tests were made with two sizes of ordinary ailerons and different sizes of spoilers on a Clark Y wing model having a narrow auxiliary airfoil fixed ahead and above the leading edge, the chords of the main and auxiliary airfoils being parallel. In addition, the auxiliary airfoil itself was given angular deflection. The purpose was to provide rolling moments for lateral control.
Date: March 1933
Creator: Weick, Fred E. & Noyes, Richard W.
Partner: UNT Libraries Government Documents Department

Wind Tunnel Research Comparing Lateral Control Devices, Particularly at High Angles of Attack 8: Straight and Skewed Ailerons on Wings With Rounded Tips

Description: Tests showed the effect of the ailerons and the tip shapes on the general performance of the wing, as well as on the lateral control and stability characteristics. The hinge moments were not measured but the approximate values are given in the first report of the series.
Date: February 1933
Creator: Weick, Fred E. & Shortal, Joseph A.
Partner: UNT Libraries Government Documents Department

The Behavior of Conventional Airplanes in Situations Thought to Lead to Most Crashes

Description: Simple flight tests were made on ten conventional airplanes for the purpose of determining their action in two situations, which are generally thought to precede and lead to a large proportion of airplane crashes. These situations are when in an attempt to stretch the glide in a forced landing, the airplane is stalled, and when while taking off, particularly if taking off steeply, the engine fails at a low altitude.
Date: February 1931
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Navy Propeller Section Characteristics as Used in Propeller Design

Description: "This report contains artificial aerodynamic characteristics of a set of propeller sections to be used in designing propellers by means of the blade element theory. Characteristics computed from model propeller tests for a single section are extended to cover sections of Navy propeller sections at high Reynolds Number in the variable density tunnel of the NACA" (p. 1).
Date: August 1926
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Drag and Cooling With Various Forms of Cowling for a Whirlwind Engine in a Cabin Fuselage

Description: An investigation on the cowling of radial air-cooled engines was conducted in the 20-foot Propeller Research Tunnel at Langley Field. Cooling and drag tests were made with each form of cowling. The propulsive efficiency was found to be practically the same with all forms of cowling.
Date: November 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

The Drag of a J-5 Radial Air-Cooled Engine

Description: This note describes tests of the drag due to a Wright "Whirlwind" (J-5) radial air-cooled engine mounted on a cabin type airplane. The tests were made in the 20-foot Propeller Research Tunnel of the National Advisory Committee for Aeronautics. The drag was obtained with three different types of exhaust stacks: Short individual stacks, a circular cross section collector ring, and a streamline cross section collector ring.
Date: July 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Full Scale Investigation of the Drag of a Wing Radiator

Description: Tests were made on the 1927 Williams racer in order to determine the effect of the wing radiator on the airfoil characteristics. It was found that the radiator doubled the minimum drag of the portion of the wing it covered, and also reduced the lift somewhat.
Date: September 1929
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

A Comparison of Propeller and Centrifugal Fans for Circulating the Air in a Wind Tunnel

Description: The tests described in this paper afford a direct comparison of the efficiency and smoothness of flow obtained with propeller fan and multiblade centrifugal fan drives in the same wind tunnel. The propeller fan was found to be superior to the centrifugal fan in that the efficiency was about twice as great, and the flow much smoother.
Date: March 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Tests of Four Racing Type Airfoils in the Twenty-Foot Propeller Research Tunnel

Description: Tests were made on four racing type airfoils, the N-9, N-38, C-62, and N-46, in order to determine the high speed characteristics of the wings. The results indicate that the N-46 has about 12 percent lower minimum drag than the regular C-62 section, and that both the N-38 and N-46 have the same exceptionally low minimum drag coefficient.
Date: September 1929
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

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

Description: "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.
Partner: UNT Libraries Government Documents Department

Determination of Propeller Deflection by Means of Static Load Tests on Models

Description: "This note describes a simple and inexpensive method for determining the deflection of propeller blades under operating loads. Both the centrifugal force and air force loads are applied statically as a number of concentrated loads by means of weights and wires. Two methods of attaching the wires to the propeller blades have been tested, both giving approximately the same deflections. The method is considered useful for studying the deflections of propellers of different shapes under various operating conditions" (p. 1).
Date: January 1928
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department