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An approximate spin design criterion for monoplanes, 1 May 1939

Description: An approximate empirical criterion, based on the projected side area and the mass distribution of the airplane, was formulated. The British results were analyzed and applied to American designs. A simpler design criterion, based solely on the type and the dimensions of the tail, was developed; it is useful in a rapid estimation of whether a new design is likely to comply with the minimum requirements for safety in spinning.
Date: January 1, 1976
Creator: Seidman, O. & Donlan, C. J.

Spin tests of a low-wing monoplane to investigate scale effect in the model test range, May 1941

Description: Concurrent tests were performed on a 1/16 and a 1/20 scale model (wing spans of 2.64 and 2.11 ft. respectively) of a modern low wing monoplane in the NACA 15 foot free-spinning wind tunnel. Results are presented in the form of charts that afford a direct comparison between the spins of the two models for a number of different conditions. Qualitatively, the same characteristic effects of control disposition, mass distribution, and dimensional modifications were indicated by both models. Quantitatively, the number of turns for recover and the steady spin parameters, with the exception of the inclination of the wing to the horizontal, were usually in good agreement.
Date: January 1, 1976
Creator: Donlan, C. J.

An Analysis of Ramjet Engines Using Supersonic Combustion

Description: From Introduction: "The concept of supersonic combustion is by no means new, although little work appears to have been published on the subject. For example, an analysis of supersonic combustion to provide lift under a wing is given in reference 1. Reference 2 discusses applications to hypersonic ramjets being studied at the University of Michigan."
Date: September 1958
Creator: Weber, Richard J. & MacKay, John S.

Analysis of the creep behavior of a square plate loaded in edge compression

Description: From Introduction: "In reference 1 results of creep tests and empirical method for predicting collapse times are presented for plates loaded in compression on two opposite edges and with the remaining edges unloaded and supported in V-groove fixtures. Other approximate methods for handling plates having types of edge support are suggested in reference 2; however, experimental verification for these methods is quite limited. In reference 3 an analysis based on small-deflection theory is made of the creep deflection of a simply supported plate composed of a linear viscoelastic material - that is, a material in which the stress and strain and their appropriate time derivatives are related in a linear fashion."
Date: September 1958
Creator: Mccomb, Harvey G , Jr

Analysis of turbulent flow and heat transfer in noncircular passages

Description: From Introduction: "In reference 1, wall temperature distributions for turbulent flow in rectangular and triangular ducts were calculated by using experimental velocity distributions and average heat-transfer coefficients, together with assumed similarity of the wall heat-transfer and wall shear-stress variations; no attempt was made to calculate either the heat-transfer coefficients or the velocity and temperature distributions in the fluid field. Some calculations of velocity and shear-stress distributions in corners are reported in reference 2."
Date: September 1958
Creator: Deissler, Robert G & Taylor, Maynard F

Approximate method for calculating motions in angles of attack and sideslip due to step pitching- and yawing-moment inputs during steady roll

Description: Report presenting an extension of a method for calculating motions in angles of attack and sideslip resulting from a trim angle of attack and steady rolling velocity to the condition of pitching- and yawing-moment inputs. The resulting formulas are intended primarily for rolling-velocity conditions in which rolling divergence is not encountered.
Date: September 1958
Creator: Moul, Martin T. & Brennan, Teresa R.

Approximate solutions of a class of similarity equations for three-dimensional, laminar, incompressible boundary-layer flows

Description: Report presenting an analysis for obtaining approximate solutions of the similarity equations for three-dimensional laminar-boundary-layer flows over a flat surface under main-flow streamlines that are translates and representable as infinite series expansions.
Date: September 1958
Creator: Hansen, Arthur G. & Herzig, Howard Z.

Cumulative fatigue damage at elevated temperature

Description: From Summary: "A study of cumulative fatigue damage at elevated temperatures was conducted using heat-treated SAE 4130 alloy steel. The S-N curves at room temperature, 400 degrees Fahrenheit, and 800 degrees Fahrenheit were obtained from rotating-beam fatigue tests. Two-step, three-step, and five-step cumulative-damage fatigue tests were conducted on rotating-beam fatigue specimens at room temperature, 400 degrees Fahrenheit, and 800 degrees Fahrenheit. The results of the cumulative-damage tests are compared with those of a theoretical analysis."
Date: September 1958
Creator: Rey, William K.

Effect of pressure and duct geometry on bluff-body flame stabilization

Description: Report presenting blowoff velocities and recirculation-zone lengths of propane-air flames stabilized by cylindrical flameholders measured as a function of pressure, cylinder diameter, fuel-air ratio, and tunnel geometry for a range of Reynolds numbers. Results regarding blowoff velocities, recirculation-zone lengths, critical time, and heat losses from recirculation zone are provided.
Date: September 1958
Creator: Potter, Andrew E., Jr. & Wong, Edgar L.

Effects of compressibility on rotor hovering performance and synthesized blade-section characteristics derived from measured rotor performance of blades having NACA 0015 airfoil tip sections

Description: Report presenting an investigation to determine the low tip Mach number blade maximum mean lift coefficients and the high tip Mach number effects of compressibility for rotor blades with NACA 0015 tip airfoil sections. The characteristics of this rotor was similar to those from other investigations, which is that at low Mach numbers, there is a stable pitching moment past rotor-blade drag divergence. Results regarding hovering performance, synthesized rotor-blade section characteristics, rotor-blade pitching moments, rotor-blade profile-drag torque, comparison of profile-drag torque ratios, and a comparison of experimental and two-dimensional drag-divergence characteristics are provided.
Date: September 1958
Creator: Shivers, James P. & Carpenter, Paul J.

Effects of frequency and amplitude on the yawing derivatives of triangular, swept, and unswept wings and of a triangular-wing-fuselage combination with and without a triangular tail performing sinusoidal yawing oscillations

Description: Report presenting an investigation to determine the effects of frequency and amplitude on the yawing derivatives of triangular, swept, and unswept wings. Results regarding the damping in yaw, rolling moment due to yawing, acceleration derivatives, and comparison of yawing and acceleration derivatives with combined derivatives for wings alone are provided for configurations of the wing alone and wing-body combinations.
Date: September 1958
Creator: Letko, William & Fletcher, Herman S.

Effects of ground proximity on the thrust of a simple downward-directed jet beneath a flat surface

Description: Report presenting an investigation to determine the effects of some of the basic parameters on the thrust of a simple downward-directed jet beneath a flat plate in a static-thrust facility. Some of the variables investigated included the size and shape of the flat plate, aspect ratio of the plate, distance of the flat plate and nozzle exit above the ground, and surface conditions of the ground.
Date: September 1958
Creator: Spreemann, Kenneth P. & Sherman, Irving R.

Effects of nose angle and Mach number on transition on cones at supersonic speeds

Description: An investigation has been made to determine the transition characteristics of a group of smooth, sharp-nosed cones varying from 10 degrees to sixty degrees in included apex angle over a Mach number range from 1.61 to 2.20 and a range of Reynolds number per foot from about 1.5 x 10 to the 6th power to 8 x 10 to the 6th power. Increasing the cone angle is shown to decrease slightly the transition Reynolds number, whereas the effects of changes of Mach number and unit Reynolds number are negligible. When transition occurred within 15 to 20 percent of the model length from the base there was a dropoff in transition Reynolds number. (author).
Date: September 1, 1958
Creator: Czarnecki, K R & Jackson, Mary W