An Introduction to the Laws of Air Resistance of Aerofoils (open access)

An Introduction to the Laws of Air Resistance of Aerofoils

Report presents methods of calculating air resistance of airfoils under certain conditions of flow phenomena around the airfoil.
Date: September 1918
Creator: de Bothezat, George
System: The UNT Digital Library
Annual Report of the National Advisory Committee for Aeronautics (3rd). Administrative Report Including Technical Report Nos. 13 to 23 (open access)

Annual Report of the National Advisory Committee for Aeronautics (3rd). Administrative Report Including Technical Report Nos. 13 to 23

Report includes the National Advisory Committee for Aeronautics letter of submittal to the President, Congressional report, summaries of the committee's activities and research accomplished, expenditures, and problems.
Date: 1918
Creator: unknown
System: The UNT Digital Library
Experimental Research on Air Propellers (open access)

Experimental Research on Air Propellers

The purposes of the experimental investigation on the performance of air propellers described in this report are as follows: (1) the development of a series of design factors and coefficients drawn from model forms distributed with some regularity over the field of air-propeller design and intended to furnish a basis of check with similar work done in other aerodynamic laboratories, and as a point of departure for the further study of special or individual types and forms; (2) the establishment of a series of experimental values derived from models and intended for later use as a basis for comparison with similar results drawn from certain selected full-sized forms and tested in free flight.
Date: 1918
Creator: Durand, William F.
System: The UNT Digital Library
Nomenclature for Aeronautics (open access)

Nomenclature for Aeronautics

Report defines the principal terms which have come into use in the development of aeronautics.
Date: 1918
Creator: unknown
System: The UNT Digital Library
The Stretching of the Fabric and the Deformation of the Envelope in Nonrigid Balloons (open access)

The Stretching of the Fabric and the Deformation of the Envelope in Nonrigid Balloons

Report presents the performance of fabrics used for the envelopes of airships.
Date: 1918
Creator: Haas, Rudolf & Dietzius, Alexander
System: The UNT Digital Library
An Investigation of the Elements Which Contribute to Statical and Dynamical Stability, and of the Effects of Variation in Those Elements (open access)

An Investigation of the Elements Which Contribute to Statical and Dynamical Stability, and of the Effects of Variation in Those Elements

Part 1 gives details of models tested and methods of testing of the Eiffel 36 wing alone and the JN2 aircraft. Part 2 presents a statistical analysis of the following: lift and drag contributed by body and chassis tested without wings; lift and drag contributed by tail, tested without wings; the effect on lift and drift of interference between the wings of a biplane combination; lift and drag contributed by the addition of body, chassis, and tail to a biplane combination; total parasite resistance; effect of varying size of tail, keeping angle of setting constant; effect of varying length of body and size of tail at the same time, keeping constant moment of tail surface about the center of gravity; forces on the tail and the effects of downwash; effect of size and setting of tail on statical longitudinal stability effects of length of body on stability; the effects of the various elements of an airplane on longitudinal stability and the placing of the force vectors. Part 3 presents the fundamental principals of dynamical stability; computations of resistance derivatives; solution of the stability equation; dynamical stability of the Curtiss JN2; tabulation of resistance derivatives; discussion of the resistance derivatives; formation …
Date: 1918
Creator: Klemin, Alexander; Warner, Edward P. & Denkinger, George M.
System: The UNT Digital Library
Periodic Stresses in Gyroscopic Bodies, With Applications to Air Screws (open access)

Periodic Stresses in Gyroscopic Bodies, With Applications to Air Screws

Report discusses periodic stresses in gyroscopic bodies with applications to air screws caused by particle mass. Report concludes that all modern air screws obey the laws found for plane groups of particles. In particular the two-bladers exert on the shaft a rhythmic gyroscopic torque; the multibladers a steady one; both easily calculable for any given conditions of motion and mass distribution.
Date: 1918
Creator: Zahm, A. F.
System: The UNT Digital Library
Aerofoils and Aerofoil Structural Combinations (open access)

Aerofoils and Aerofoil Structural Combinations

Report presents results of wind tunnel tests of cambered aerofoils and body-wing combinations used for biplanes. Aerodynamic characteristics including drag, lift-drift ratio and stability derivatives are given.
Date: 1918?
Creator: Gorrell, Edgar S. & Martin, H. S.
System: The UNT Digital Library
Aerodynamic Coefficients and Transformation Tables (open access)

Aerodynamic Coefficients and Transformation Tables

From Introduction: "The following brief explanation with tables of equivalents in various systems of units, has been prepared in order to facilitate such transformation."
Date: 1918~
Creator: Ames, Joseph S.
System: The UNT Digital Library
Fabrics for Aeronautic Construction (open access)

Fabrics for Aeronautic Construction

The Bureau of Standards undertook the investigation of airplane fabrics with the view of finding suitable substitutes for the linen fabrics, and it was decided that the fibers to be considered were cotton, ramie, silk, and hemp. Of these, the cotton fiber was the logical one to be given primary consideration. Report presents the suitability, tensibility and stretching properties of cotton fabric obtained by laboratory tests.
Date: 1918
Creator: Walen, E. D.
System: The UNT Digital Library
Air Flow Through Poppet Valves (open access)

Air Flow Through Poppet Valves

Report discusses the comparative continuous flow characteristics of single and double poppet valves. The experimental data presented affords a direct comparison of valves, single and in pairs of different sizes, tested in a cylinder designed in accordance with current practice in aviation engines.
Date: 1918
Creator: Lewis, G. W. & Nutting, E. M.
System: The UNT Digital Library
Theory of an Airplane Encountering Gusts, 3 (open access)

Theory of an Airplane Encountering Gusts, 3

Report presents a new method for solving linear equations developed by Bromwich, which is suited to determine the motion for any particular gust, when the machine started from equilibrium, without the trouble of determining the constants of integration in the complementary function. (author).
Date: October 15, 1918
Creator: Wilson, Edwin Bidwell
System: The UNT Digital Library
Airplane stress analysis (open access)

Airplane stress analysis

Report presents stress analysis of individual components of an airplane. Normal and abnormal loads, sudden loads, simple stresses, indirect simple stresses, resultant unit stress, repetitive and equivalent stress, maximum steady load and stress are considered.
Date: January 1918
Creator: Zahm, A. F. & Crook, L. H.
System: The UNT Digital Library