You limited your search to:

  Partner: UNT Libraries Government Documents Department
 Serial/Series Title: NACA Technical Reports
 Collection: National Advisory Committee for Aeronautics Collection
Full-scale turning characteristics of the U.S.S. Los Angeles

Full-scale turning characteristics of the U.S.S. Los Angeles

Date: January 1, 1930
Creator: Thompson, F L
Description: This paper present a description of the method employed and results obtained in full-scale turning trials on the rigid airship U. S. S. "Los Angeles". The results of this investigation are not sufficiently comprehensive to permit definite conclusions as to the variation of turning characteristics with changes in speed and rudder angle. They indicate however, that the turning radius compares favorably with that for other large airships, that the radius is independent of the speed, that the position of the point of zero yaw is nearly independent of the rudder angle and air speed, and that a theoretical relation between radius and angle of yaw in a turn gives a close approximation to actuality.
Contributing Partner: UNT Libraries Government Documents Department
Flight tests on U.S.S. Los Angeles. Part II : stress and strength determination

Flight tests on U.S.S. Los Angeles. Part II : stress and strength determination

Date: January 1, 1930
Creator: Burgess, C P
Description: The tests described in this report furnished data on the actual aerodynamic forces, and the resulting stresses and bending moments in the hull of the U. S. S. "Los Angeles" during as severe still-air maneuvers as the airship would normally be subjected to, and in straight flight during as rough air as is likely to occur in service, short of squall or storm conditions. The maximum stresses were found to be within the limits provided for in accepted practice in airship design. Normal flight in rough air was shown to produce forces and stresses about twice as great as the most severe still-air maneuvers. No light was thrown upon the forces which might occur in extreme or exceptional conditions, such as the storm which destroyed the "Shenandoah". The transverse aerodynamic forces on the hull proper were found to be small and irregular. Owing to the necessity of conserving helium, it was impossible to fly the airship in a condition of large excess of buoyancy or weight in order to determine the air pressure distribution at a fixed angle of pitch. However, there is every reason to believe that in that condition the forces on the actual airship are as close ...
Contributing Partner: UNT Libraries Government Documents Department
The torsion of members having sections common in aircraft construction

The torsion of members having sections common in aircraft construction

Date: January 1, 1930
Creator: Trayer, George W
Description: Within recent years a great variety of approximate torsion formulas and drafting-room processes have been advocated. In some of these, especially where mathematical considerations are involved, the results are extremely complex and are not generally intelligible to engineers. The principal object of this investigation was to determine by experiment and theoretical investigation how accurate the more common of these formulas are and on what assumptions they are founded and, if none of the proposed methods proved to be reasonable accurate in practice, to produce simple, practical formulas from reasonably correct assumptions, backed by experiment. A second object was to collect in readily accessible form the most useful of known results for the more common sections. Formulas for all the important solid sections that have yielded to mathematical treatment are listed. Then follows a discussion of the torsion of tubular rods with formulas both rigorous and approximate.
Contributing Partner: UNT Libraries Government Documents Department
The torsional strength of wings

The torsional strength of wings

Date: January 1, 1930
Creator: Burgess, C P
Description: This report describes a simple method for calculating the position of the elastic axis of a wing structure having any number of spars. It is shown that strong drag bracing near the top and bottom of a wing greatly increases the torsional strength. An analytical procedure for finding the contribution of the drag bracing to the torsional strength and stiffness is described, based upon the principle of least work, and involving only one unknown quantity. A coefficient for comparing the torsional rigidity of different wings is derived in this report.
Contributing Partner: UNT Libraries Government Documents Department
Aerodynamic theory and tests of strut forms. Part II

Aerodynamic theory and tests of strut forms. Part II

Date: January 1, 1930
Creator: Smith, R H
Description: This report presents the second of two studies under the same title. In this part five theoretical struts are developed from distributed sources and sinks and constructed for pressure and resistance tests in a wind tunnel. The surface pressures for symmetrical inviscid flow are computed for each strut from theory and compared with those found by experiment. The theoretical and experimental pressures are found to agree quantitatively near the bow, only qualitatively over the suction range, the experimental suctions being uniformly a little low, and not at all near the stern. This study is the strut sequel to Fuhrmann's research on airship forms, the one being a study in two dimensions, the other in three. A comparison of results indicates that the agreement between theory and experiment is somewhat better for bodies of revolution than for cylinders when both are shaped for slight resistance. The consistent deficiency of the experimental suctions which is found in the case of struts was not found in the case of airships, for which the experimental suctions were sometimes above sometimes below their theoretical values.
Contributing Partner: UNT Libraries Government Documents Department
Method for studying helicopter longitudinal maneuver stability

Method for studying helicopter longitudinal maneuver stability

Date: January 1, 1954
Creator: Amer, Kenneth B
Description: A theoretical analysis of helicopter maneuver stability is made and the results are compared with experimental results for both a single and a tandem rotor helicopter. Techniques are described for measuring in flight the significant stability derivatives for use with the theory to aid in design studies of means for achieving marginal maneuver stability for a prototype helicopter.
Contributing Partner: UNT Libraries Government Documents Department
Summary of methods for calculating dynamic lateral stability and response and for estimating aerodynamic stability derivatives

Summary of methods for calculating dynamic lateral stability and response and for estimating aerodynamic stability derivatives

Date: January 1, 1952
Creator: Campbell, John P
Description: A summary of methods for making dynamic lateral stability and response calculations and for estimating the aerodynamic stability derivatives required for use in these calculations is presented. The processes of performing calculations of the time histories of lateral motions, of the period and damping of these motions, and of the lateral stability boundaries are presented as a series of simple straightforward steps. Existing methods for estimating the stability derivatives are summarized and, in some cases, simple new empirical formulas are presented. Detailed estimation methods are presented for low-subsonic-speed conditions but only a brief discussion and a list of references are given for transonic and supersonic speed conditions.
Contributing Partner: UNT Libraries Government Documents Department
Preliminary investigation of a new type of supersonic inlet

Preliminary investigation of a new type of supersonic inlet

Date: January 1, 1952
Creator: Ferri, Antonio
Description: A supersonic inlet with supersonic deceleration of the flow entirely outside of the inlet is considered a particular arrangement with fixed geometry having a central body with a circular annular intake is analyzed, and it is shown theoretically that this arrangement gives high pressure recovery for a large range of Mach number and mass flow and, therefore, is practical for use on supersonic airplanes and missiles. Experimental results confirming the theoretical analysis give pressure recoveries which vary from 95 percent for Mach number 1.33 to 86 percent for number 2.00. These results were originally presented in a classified document of the NACA in 1946.
Contributing Partner: UNT Libraries Government Documents Department
Effects of wing position and fuselage size on the low-speed static rolling stability characteristics of a delta-wing model

Effects of wing position and fuselage size on the low-speed static rolling stability characteristics of a delta-wing model

Date: January 1, 1955
Creator: Goodman, Alex
Description: An investigation was made to determine the effects of wing position and fuselage size on the low-speed static and rolling stability characteristics of airplane models having a triangular wing and vertical tail surfaces. (author).
Contributing Partner: UNT Libraries Government Documents Department
Chordwise and compressibility corrections to slender-wing theory

Chordwise and compressibility corrections to slender-wing theory

Date: January 1, 1952
Creator: Lomax, Harvard
Description: Corrections to slender-wing theory are obtained by assuming a spanwise distribution of loading and determining the chordwise variation which satisfies the appropriate integral equation. Such integral equations are set up in terms of the given vertical induced velocity on the center line or, depending on the type of wing plan form, its average value across the span at a given chord station. The chordwise distribution is then obtained by solving these integral equations. Results are shown for flat-plate rectangular, and triangular wings.
Contributing Partner: UNT Libraries Government Documents Department