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open access

Lift and drag data for 30 pusher-propeller shaft housings on an NACA 65,3-018 airfoil section

Description: Report presenting tests in the two-dimensional low-turbulence pressure tunnel to study the interference effects of various pusher-propeller shaft-housing combinations on a low-drag airfoil. Thirty different combinations were tested, variations being made in shaft size, shape, angle, and fillet.
Date: November 1943
Creator: Abbott, Frank T., Jr.
open access

Preliminary Tests to Determine the Dynamic Stability Characteristics of Various Hydrofoil Systems for Seaplanes and Surface Boats

Description: Report discusses the results of testing on the dynamic stability characteristics of various hydrofoil systems for seaplanes, including a flat-hydrofoil tandem system, a 20 degree V-hydrofoil tandem system, a curved-hydrofoil tandem system, a flat-hydrofoil ladder system, a Guidoni S.V.A.-type hydrofoil on a streamline spindle, and several self-propelled models, including the Tietjens hydrofoil system. The instability and spray were compared for the different systems.
Date: November 1943
Creator: Benson, James M. & King, Douglas A.
open access

Wind-Tunnel Tests of a Piston-Type Control Booster on an Airfoil and Aileron Model

Description: "Measurements of control moments were made in the NACA stability tunnel to determine the operational characteristics of a piston-type control booster on an aileron. The booster was so constructed and installed that pressures picked up from the air stream below the wing acted on a pair of pistons. The data are presented in the form of curves of pressure coefficients acting on the pistons, hinge-moment coefficients, and booster coefficients plotted against aileron deflection" (p. 1).
Date: November 1943
Creator: Bird, J. D. & Mendelsohn, Robert A.
open access

A Theoretical Investigation of the Rolling Oscillations of an Airplane With Ailerons Free

Description: "An analysis is made of the stability of an airplane with ailerons free, with particular attention to the motions when the ailerons have a tendency to float against the wind. The present analysis supersedes the aileron investigation contained in NACA Technical Report no. 709. The equations of motion are first written to include yawing and sideslipping, and it is demonstrated that the principal effects of freeing the ailerons can be determined without regard to these motions" (p. 255).
Date: November 19, 1943
Creator: Cohen, Doris
open access

The Resonance Absorption Spectrum of Uranium

Description: A model for the capture spectrum of uranium is introduced in which levels occur at 7, 30, 30+D, 30+2D, ..., ev. Gamma ray and neutron widths are derived from the experimental data for values of D between 10 and 25 ev. The constants of the 7 volt level prove to be independent of D. Extrapolation, using the one level formula, gives a capture cross section at (1/40) ev of 4.9 x 10(24) cm2; this number is, however, quite sensitive to the value taken for the resonance activation. Both neutron and ga… more
Date: November 24, 1943
Creator: Dancoff, Sidney M., 1913-1951
open access

Recent Developments in Fuel Supply and Demand

Description: Report issued by the U.S. Bureau of Mines discussing the recent supply and demand of fuels. As stated by the author, "my purpose in this address is to review the changes in fuel supply and demand since 1937 and to give you my views on the outlook for the future" (p. 1). This report includes tables, and illustrations.
Date: November 1943
Creator: Fieldner, Arno Carl
open access

On the plane potential flow past a lattice of arbitrary airfoils

Description: The two-dimensional, incompressible potential flow past a lattice of airfoils of arbitrary shape is investigated theoretically. The problem is treated by usual methods of conformal mapping in several stages, one stage corresponding to the mapping of the framework of the arbitrary line lattice and another significant stage corresponding to the Theodorsen method for the mapping of the arbitrary single wing profile into a circle. A particular feature in the theoretical treatment is the special han… more
Date: November 19, 1943
Creator: Garrick, I. E.
open access

Experimental Investigation of Entrance-Region Heat-Transfer Coefficients

Description: "Experimental results of tests made at the Langley Memorial Aeronautical Laboratory are presented to show how heat-transfer coefficients can be increased by a method utilizing the high rate of heat transfer known to exist on any heat-transfer surface in the region adjacent to the edge on which the cooling or heating fluid impinges. The results show that, for the same pressure drop, the average surface heat-transfer.coefficient can be increased 50 to 100 percent when a cooling surface having a l… more
Date: November 1943
Creator: Joyner, Upshur T.
open access

Charts for calculation of the critical stress for local instability of columns with I-, Z-, channel and rectangular-tube section

Description: Report presenting charts for the calculation of the critical stress for local instability of columns with I-, Z-, channel-, and rectangular-tube sections. An experimental curve is included for use in taking into account the effect of stresses above the elastic range on 24S-T aluminum alloy elasticity.
Date: November 1943
Creator: Kroll, W. D.; Fisher, Gordon P. & Heimerl, George J.
open access

Wind Tunnel Tests of Ailerons at Various Speeds 5: Pressure Distributions Over the NACA 66,2-216 and NACA 23012 Airfoils With Various Balances on 0.20-Chord Ailerons

Description: Report presenting pressure distribution testing of an NACA 66,2-216, a = 1.0 airfoil equipped with a blunt nose balance aileron and a sealed internal-balance aileron and of an NACA 23012 airfoil equipped with a Frise aileron and a blunt nose balance aileron in the stability tunnel. Results regarding the section pressure distribution and section loads and moments are provided.
Date: November 1943
Creator: Letko, W. & Denaci, H. G.
open access

Capture Cross Section of Pb208 for C Neutrons

Description: From abstract: "Using the method of induced radioactivity, the capture cross section of Pb[^]208 for C neutrons is found to be .00045 ± .00015 x 10[^]-24 cm[^]2. This is definitely lower than the value of .001 x 10[^]-24 reported by Maurer and Ramm."
Date: November 5, 1943
Creator: Levinger, Joseph S., 1921-; Compton, A. H.; Allison, Samuel King, 1900-1965; Watson, W. W. & Snell, A. H.
open access

Principles of Moment Distribution Applied to Stability of Structures Composed of Bars or Plates

Description: Principles of the cross method of moment distribution, which have previously been applied to the stability of structures composed of bars under axial load, are applied to the stability of structures composed of long plates under longitudinal load.
Date: November 1943
Creator: Lundquist, Eugene E.; Stowell, Elbridge Z. & Schuette, Evan H.
open access

Design criterions for the dimensions of the forebody of a long-range flying boat

Description: Report presenting a correlation of the gross-load coefficient and the forebody length-beam ratio for a limited number of present-day multiengine long-range flying boats for which the spray characteristics are known. Results indicate that the gross-load coefficient for comparable spray characteristics varies as the square of the forebody length-beam ratio.
Date: November 1943
Creator: Parkinson, John B.
open access

A Comparative Study of the Effect of Wing Flutter Shape on the Critical Flutter Speed

Description: Report presenting a comparison of the results of calculations of the critical flutter speeds of nine uniform rectangular wings without ailerons by two methods: one in which the effect of the wing flutter shape is introduced indirectly by choosing mean values for the wing parameters and one that introduces an additional degree of freedom in the wing-bending flutter mode.
Date: November 1943
Creator: Pinkel, I. Irving
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