From Introduction: "Early in 1951 the National Advisory Committee for Aeronautics published, as Technical Note 2276 (ref. 1), a report by the Aluminum Research Laboratories of the Aluminum Company of America on the results of static and fatigue tests of high-strength aluminum alloy monobloc specimens and bolted joints. In view of special interest shown by several aircraft companies, certain expansions of the test program were undertaken by the Aluminum Research Laboratories and are reported herein."

From Introduction: "The present paper contains a first-order evaluation of a number of aerodynamic derivatives for a rectangular wing of infinite aspect ratio at finite angles of attack, based upon the linear perturbation theory for rotational flow."

From Introduction: "The primary purpose of the investigation described in the present report is to formulate a method which is of value for quantitative calculations of base pressure on airfoils and bodies without boat-tailing. Part I consists of a detailed study of the base pressure in two-dimensional and axially-symmetric inviscid flow. In part II a semi-empirical theory is formulated since the results of part I indicate that an inviscid-flow theory cannot possibly be satisfactory for quantitative calculations of a viscous flow."

From Introduction: "The buzz or pulsation of axially symmetric supersonic inlets having central bodies has been the subject of investigations since Oswatitsch first observed the phenomenon in 1944 (ref.1). This buzzing is essentially an oscillation of the normal shock along the spike of certain diffusers operating at mass flows below design, and this buzz decreases the performance of the propulsion units appreciably (ref.2). This paper continues the analysis of the buzzing cycle by means of a modified one-dimensional approach."

Report presenting normal-acceleration and airspeed data obtained from V-G recorders installed in a two-engine type of transport airplane, employed in routine commercial operation in the United States for two years, which was analyzed to determine the gust and gust-load experiences of the airplane. Results regarding the acceleration experience, gust experience, average operating airspeed, maximum airspeed, comparison of predicted gust envelopes, and predicted gust-load envelopes are provided.

Report presenting the effect of compressibility on the loss characteristics downstream of two-dimensional turbomachine blade rows. In this particular example, increasing the trailing-edge thickness increased the overall loss coefficients significantly, with an effect of compressibility only at exit flow angles close to axial.

Note presenting equations derived for the prediction of velocity distributions for fully developed adiabtic turbulent flow in smooth tubes; both the incompressible and compressible flow cases were treated. The analysis produced a single equation that represents flow in both the conventional buffer layer and the laminar layer. The results for fully developed flow were correlated by using conventional dimensionless velocity and distance parameters, and agreed closely with those of Nikuradse and other investigators.

"In the analytical investigation reported herein, which was conducted in the NACA Lewis laboratory, both velocity and temperature distribution are obtained for fully developed laminar flow in tubes of gases and of liquid metals with variable fluid properties" (p. 1).

Report presenting an analysis of two x-ray absorption methods for determining small air-density gradients. One method uses a Geiger-Mueller counter for detection and the other uses photographic film for detection. Both of the methods are found to have some advantages and disadvantages.

From Summary: "Aerodynamic influence coefficients for symmetrically loaded wings of arbitrary plan form in subsonic flow are derived from a simple empirical method of estimating spanwise lift distributions. The application of the coefficients to an aeroelastic analysis is discussed."

Note presenting an approximate blade-element design method for compressible or incompressible nonviscous flow in high-solidity stators or rotors of axial-, radial-, or mixed-flow compressors, turbines, or two-dimensional cascades. The method is based upon channel-type flow between blade elements on a specified surface of revolution that lies between the hub and shroud and is concentric with the axis of the compressor turbine.

Report presenting a method for estimating the equilibrium operating line for a compressor as a component part of a turbojet engine. Charts are presented for locating the equilibrium operating line on the performance map of the compressor component of a turbojet engine operating at sea-level static conditions. Results regarding design-point operation, off-design operation, effect of compressor-discharge bleed, effect of jet-nozzle adjustment, and an example are provided.

Note presenting the development of the axial-momentum theory for compressible flow as a step in the formulation of a rational propeller theory for compressible flow. The simple theory neglects some properties but predicts flow conditions through a propeller that are significantly different from the conditions predicted by the incompressible-flow theory.

Report presenting a review of available information on the behavior of brittle and ductile materials under conditions of thermal stress and thermal shock. A number of practical methods that have been used to minimize the negative effects of thermal stress and shock are provided.

Note presenting testing of an autopilot sensitive to yawing acceleration, which was used to control four simulated airplane (mass-spring) configurations, and a series of bench tests to determine the response characteristics of the combinations.

Twenty-five ring-stiffened circular cylinders were loaded to failure in bending. The results are presented in the form of design curves which are applicable to cylinders with heavy rings that fail as a result of local buckling.

Report presenting some simple approximate solutions that are derived for the relationships between rotor thrust and flight path velocity components and the rotor blade angle, torque, and in-plane forces.

From Summary: "Ward's slender-body-theory formula for zero-lift drag contains three integrals plus a base-drag term. Two of these integral terms depend only upon the cross-sectional area distribution of the body. The third integral term depends only upon the body shape and axial slopes at the base of the body. This term is neglected in the transonic area rule because in many cases it is zero; however, there are also many cases in which it is not zero. This paper examines the term for the possibility of drag reduction for a particular case."

Experimental and theoretical results are presented for boundary layer studies consisting of Schlieren observations and momentum surveys made on hollow cylinder models with their axes aligned parallel to the stream. Results were obtained for three model diameters and for natural and artificially induced turbulent boundary layer flows.

Note presenting an investigation of the laminar boundary layer on a cooled 20 degree cone at Mach numbers of 1.5 and 2.0 to determine the variation of the position of transition with surface temperature for both constant surface temperatures and surface temperatures that increased toward the rear of the cone. The increase in the extent of the laminar boundary layer for uniform surface temperatures was found to be directly proportional to the difference between the surface and recovery temperatures.

Note presenting some calculations made on the basis of simplifying assumptions to determine the effect on the ground-run distance of maintaining a nose-high attitude instead of a three-point attitude in landings of several types of jet airplanes on slippery runways. The airplanes considered were a swept-wing transport and unswept-, swept-, and delta-wing fighters. Results regarding the effect of airplane attitude and effect of flap retraction are provided.

Report presenting exact and approximate methods based on linearized supersonic flow theory for the calculation of the velocity potential and the downwash from thin wings of arbitrary plan form. The applicability of the method inherently depends on a knowledge of the load distribution over the plan form of the wing.

Report presenting a method that has been developed for the calculation of the natural coupled or uncoupled frequencies and modes of a structure with modifications directly from the known modes and frequencies of the unmodified structure. The method is advantageous when the modes and frequencies of the unmodified structure either are known or are required along with the modes and frequencies of the structure with various modifications.

Note presenting a method of calculating two-dimensional compressible flows past thin airfoils with particular reference to the transonic speed range. The method is based on the integral form of the equation of continuity and on the intrinsic form, in terms of the streamline curvature, of the irrotationality condition.