Explore Results

open access

The determination of the effective resistance of a spindle supporting a model aerofoil

Description: An attempt was made to determine the effect of spindle interference on the lift of the airfoil by measuring moments about the axis parallel to the direction of air flow. The values obtained are of the same degree as the experimental error, and for the present this effect will be neglected. The results obtained using a U.S.A. 15 wing (plotted here) show that the correction is nearly constant from 0 degrees to 10 degrees incidence and that at greater angles its value becomes erratic. At such angl… more
Date: January 1921
Creator: Davidson, W. E. & Bacon, D. L.
Partner: UNT Libraries Government Documents Department
open access

Measurements of Rudder Moments on an Airplane During Flight

Description: Tests indicated that: 1) C airplanes with two struts are extremely susceptible to aileron maneuvers, slight alterations of the aileron sufficing to compensate great unequalized moments; 2) great unequalized moments can be produced or neutralized by the unequalized alternation of the angle of attack below the outer and inner struts. Adjustment below the outer strut is the more effective of the two. 3) When a load of bombs is suspended beyond the center of the airplane, below the wings, the bombs… more
Date: January 1921
Creator: Heidelberg, V.
Partner: UNT Libraries Government Documents Department
open access

The 300 H.P. Benz Aircraft Engine

Description: This report provides a description of the Benz 300 H.P. aircraft engine containing 12 cylinders placed at a 60° angle. It includes a detailed description of the development of the constructional points, particularly the cylinders, pistons, and connecting rods, as well as the engine fitting, lubrication, oil pumps, bearings, oil tank, fuel pump, carburetors, and cooling system. There are seven pages of illustrative figures at the end of the report.
Date: January 1921
Creator: Heller, A.
Partner: UNT Libraries Government Documents Department
open access

The optical wing aligning device of the Langley Field tunnel

Description: Described here is a convenient and accurate method of aligning the wing chord with the airflow. The device was developed to permit rapid and accurate alignment of airfoils and models with the airstream passing through the tunnel. It consists of three main parts: a projector, a reflector, and a target. The arrangement, which is shown in a figure, has proven satisfactory in operation. It is far better than the old method of sighting across a long batten, as the operator of a balance may see the t… more
Date: January 1921
Creator: Norton, F. H. & Bacon, D. L.
Partner: UNT Libraries Government Documents Department
open access

N.A.C.A. Langley field wind tunnel apparatus: The tilting manometer

Description: A description is given of a tilting manometer designed to meet the requirements of a manometer for use in the wind tunnel at the Langley Memorial Aeronautical Laboratory. This gauge was designed to meet the requirements of a manometer in use in connection with a static pressure plate to indicate the wind speed in the tunnel. The requirements are noted. The sensitivity of the gauge must be made inversely proportional to the pressure to be measured. The gauge must be accurately and quickly set fo… more
Date: January 1921
Creator: Norton, F. H. & Bacon, D. L.
Partner: UNT Libraries Government Documents Department
open access

A Preliminary Investigation of a New Method for Testing Aerofoils in Free Flight

Description: "This report is a description of a new method of testing aerofoils in free flight devised by the National Advisory Committee for Aeronautics. The method consists in lowering below a flying airplane a large inverted aerofoil on three small steel wires in such a way that the lift on the aerofoil always keeps the wires tight. The resultant force is measured by the tension in the wires, and the direction of the resultant by the amount the wing trails backwards" (p. 1).
Date: January 1922
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department
open access

Langley Field wind tunnel apparatus

Description: This report is broken up into two sections: one about the regulators for speed of wind tunnel drive motor and one about a vernier manometer with adjustable sensitivity.
Date: January 1922
Creator: Bacon, D. L.
Partner: UNT Libraries Government Documents Department
open access

Notes on the construction and testing of model airplanes

Description: Here, it is shown that the construction of an airplane model can and should be simplified in order to obtain the most reliable test data. General requirements for model construction are given, keeping in mind that the general purpose of wind tunnel tests on a model airplane is to obtain the aerodynamic characteristics, the static balance, and the efficiency of controls for the particular combination of wings, tail surfaces, fuselage, and landing gear employed in the design. These parts must be … more
Date: January 1922
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
open access

An Optical Altitude Indicator for Night Landing

Description: One of the most ingenious of the devices intended for use in night landing, especially emergency landing, is a very simple optical instrument known as the Jenkins night altitude indicator. The design and operation of this instrument, which allows a pilot to determine the altitude of the aircraft, is discussed. The author discusses various modifications and improvements that might be made to the instrument.
Date: January 1923
Creator: Warner, John A. C.
Partner: UNT Libraries Government Documents Department
open access

Downwash of Airplane Wings

Description: "The data for the calculation of the air forces acting on the elevators, obtained from previous model experiments are not immediately applicable in practice, as the angle at which the control surfaces meet the air stream is, in general, still unknown. The air stream, when it reaches the elevator has already been deflected by the wings and although the velocity imparted to the air current by the wings is of negligible amount compared with the speed of flight, the air behind the wings has been de… more
Date: January 1923
Creator: Munk, Max & Cario, Gunther
Partner: UNT Libraries Government Documents Department
open access

Results of experimental flights at high altitudes with Daimler, Benz and Maybach engines to determine mixture formation and heat utilization of fuel

Description: The experimental flights described herein were made with the object of obtaining information regarding the following two questions, which as yet have not been sufficiently elucidated. These are: 1. What effect has altitude upon the formation of the mixture? 2. What alteration takes place, with increasing altitude, in the utilization of the heat contained in the fuel?.
Date: January 1923
Creator: Kutzbach, K.
Partner: UNT Libraries Government Documents Department
open access

Effect of aerofoil aspect ratio on the slope of the lift curve

Description: On of the most important characteristics of an airfoil is the rate of change of lift with angle of attack, (sup dC)L/d alpha. This factor determines the effectiveness of a tail plane in securing static longitudinal stability. The application of the Gottingen formulas given here for calculating the variation of (sup Dc)L/d alpha with aspect ratio should be of interest to many aeronautical engineers. For the convenience of the engineer, a set of curves calculated by the method set forth here are … more
Date: January 1922
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
open access

The Dead Weight of the Airship and the Number of Passengers That Can Be Carried

Description: In order to determine an approximate formula giving the weight of a dead load as a function of the volume (V) of the envelope and of the maximum velocity (v), we will take the relative weight of the various parts of the airship (P(sub v), M, V, A, T(sup 34)), adopting a mean value of the coefficients determined. This formula may be adopted both for semi-rigid airships with suspended nacelle and non-rigid envelope, with or without internal suspensions. It may also be adapted to airships with rig… more
Date: January 1922
Creator: Crocco
Partner: UNT Libraries Government Documents Department
open access

Absolute Dimensions of Karman Vortex Motion

Description: Note presenting an investigation of the Karman vortex street, which is a flow arrangement occurring behind a plate. The equations governing the flow and some of the hypotheses behind it are provided.
Date: January 1923
Creator: Heisenberg, Werner
Partner: UNT Libraries Government Documents Department
open access

Tests on a model of the D airplane T 39 of the "Deutsche Flugzeug Werke" (German Airplane Works)

Description: 'Experiments similar to those carried out with the A.E.G (Allgemeine Elektrizitats-Gesellschaft) were made in the small wind tunnel of the Gottingen laboratory on a model of the D.F.W. airplane T-29. Three series of tests were carried out on the model with a velocity head (or dynamic pressure) of 5 kg/sq m (1.02 lb/sq ft), during which one of the movable surfaces was deflected at various angles, while both the others were retained in their central positions. Of special interest among the result… more
Date: January 1924
Creator: Molthan, Wilhelm
Partner: UNT Libraries Government Documents Department
open access

Curvilinear Flight of Airplanes

Description: Note presenting an investigation of curvilinear flight, which is defined as steady horizontal flight in a circle in which no side slip occurs. The investigation occurred under very specific circumstances and rests on two basic assumptions, which are that the airplane lies correctly in the turn so the resultant of gravity and centrifugal force falls in the plane of symmetry and that the airplane must lie in the turn so that the axis coincides with the direction of motion.
Date: January 1924
Creator: Salkowski, E.
Partner: UNT Libraries Government Documents Department
open access

Note on the Relative Effect of the Dihedral and the Sweep Back of Airplane Wings

Description: "Dihedral and sweep back can properly be compared only to the extent to which their action is similar in a side slip. In general the rolling moments due to side slip are about three to six times greater for a given dihedral angle than for an equal angle of sweep back" (p. 1).
Date: January 1924
Creator: Munk, Max M.
Partner: UNT Libraries Government Documents Department
open access

The determination of downwash

Description: It is obvious that, in accordance with Newton's second law, the lift on an aerofoil must be equal to the vertical momentum communicated per second to the air mass affected. Consequently a lifting aerofoil in flight is trailed by a wash which has a definite inclination corresponding to the factors producing the lift. It is thought that sufficient data, theoretical and experimental, are now available for a complete determination of this wash with respect to the variation of its angle of inclinati… more
Date: January 1921
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department
open access

Method of correcting wind tunnel data for omitted parts of airplane models

Description: Wind tunnel models do not have complete similarity to the full scale airplane. Part of the dissimilarity is due to the difference between the stationary model in the artificial wind stream of the tunnel and the moving airplane in still air. There are a number of other reasons for departing from exact geometrical similitude. For reasons of accuracy and economy, all minor parts of the full scale airplane, such as struts, wires, fittings, control horns and other parts whose scale corrections are l… more
Date: January 1927
Creator: Smith, R. H.
Partner: UNT Libraries Government Documents Department
open access

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
open access

Special Propeller Protractor

Description: A special protractor was designed and built with a view towards supplying a simple, inexpensive, practical, portable instrument for making measurements to detect propeller warpage under practically all conditions, without the use of auxiliary equipment, and without having to remove the propeller from the airplane. A detailed description is given of the protractor. Techniques for measuring are described. Directions are given on how to use the protractor to set detachable blade-type propellers on… more
Date: January 1928
Creator: Heim, A. L.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen