National Advisory Committee for Aeronautics (NACA) - 2,226 Matching Results

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Determination of Shapes of Boattail Bodies of Revolution for Minimum Wave Drag

Description: By use of an approximate equation for the wave drag of slender bodies of revolution in a supersonic flow field, the optimum shapes of certain boattail bodies are determined for minimum wave drag. The properties of three specific families of bodies are determined, the first family consisting of bodies having a given length and base area and a contour passing through a prescribed point between the nose and base, the second family having fixed length, base area, and maximum area, and the third family having given length, volume, and base area. The method presented is easily generalized to determine minimum-wave-drag profile shapes which have contours that must pass through any prescribed number of points. According to linearized theory, the optimum profiles are found to have infinite slope at the nose but zero radius of curvature so that the bodies appear to have pointed noses, a zero slope at the body base, and no variation of wave drag with Mach number. For those bodies having a specified intermediate.diameter (that is, location and magnitude given), the maximum body diameter is shown to be larger, in general, than the specified diameter. It is also shown that, for bodies having a specified maximum diameter, the location of the maximum diameter is not arbitrary but is determined from the ratio of base diameter to maximum diameter.
Date: August 21, 1951
Creator: Adams, Mac C.
Partner: UNT Libraries Government Documents Department

Analysis of the horizontal-tail loads measured in flight on a multiengine jet bomber

Description: From Introduction: "The primary objectives of the present paper are to report the horizontal-tail-loads measurements for configuration B which have not previously been reported and to summarize the horizontal-tail-loads results obtained with both configurations. The manner in which the aerodynamic-loads data were analyzed to include structural temperature effects and fuselage flexibility effects constitutes an important part of the present paper. "
Date: September 1955
Creator: Aiken, William S & Wiener, Bernard
Partner: UNT Libraries Government Documents Department

Analysis of horizontal-tail loads in pitching maneuvers on a flexible swept-wing jet bomber

Description: From Introduction: "The analysis of flight data in the present report is, to a large extent, based on analyses and information contained in references 1 and 2 for wing deflections, reference 3 for horizontal-tail parameters, reference 4 for airplane lift-curve slopes and angles of zero lift, and reference 5 for wing centers of pressure."
Date: December 1957
Creator: Aiken, William S , Jr
Partner: UNT Libraries Government Documents Department

A study of the motion and aerodynamic heating of missiles entering the earth's atmosphere at high supersonic speeds

Description: A simplified analysis of the velocity and deceleration history of missiles entering the earth's atmosphere at high supersonic speeds is presented. The results of this motion analysis are employed to indicate means available to the designer for minimizing aerodynamic heating. The heating problem considered involves not only the total heat transferred to a missile by convection, but also the maximum average and local time rates of convective heat transfer.
Date: October 1957
Creator: Allen, H. Julian & Eggers, A. J., Jr.
Partner: UNT Libraries Government Documents Department

Motion of a ballistic missile angularly misaligned with the flight path upon entering the atmosphere and its effect upon aerodynamic heating, aerodynamic loads, and miss distance

Description: An analysis is given of the oscillating motion of a ballistic missile which upon entering the atmosphere is angularly misaligned with respect to the flight path. The history of the motion for some example missiles is discussed from the point of view of the effect of the motion on the aerodynamic heating and loading. The miss distance at the target due to misalignment and to small accidental trim angles is treated. The stability problem is also discussed for the case where the missile is tumbling prior to atmospheric entry.
Date: October 1, 1957
Creator: Allen, Julian H
Partner: UNT Libraries Government Documents Department

Compressive crippling of structural sections

Description: A method is presented for calculating crippling stresses of structural sections as a function of material properties and the proportions of the section. The presence of formed or anisotropic material is accounted for by the use of an effective stress-strain curve. The method of analysis applies to many sections for which a procedure for calculating crippling was not previously available.
Date: January 1, 1956
Creator: Anderson, Melvin S
Partner: UNT Libraries Government Documents Department

Local instability of the elements of a truss-core sandwich plate

Description: The charts presented give the compressive buckling coefficients for a single-truss-core and a double-truss-core sandwich plate. These charts cover a wide range of sandwich proportions and may be used for sandwiches with unequal faces. They apply to inplane compressive loads acting parallel or perpendicular to the core direction or for various combinations of these loads. (author).
Date: July 1, 1958
Creator: Anderson, Melvin S
Partner: UNT Libraries Government Documents Department