Memorandum presenting a theoretical investigation to determine the reasons for poor airplane response to longitudinal control. Some effects of airplane configuration on the response, primarily for short time periods, were also determined. Results regarding a comparison of three airplanes, the effect of changes on airplane B, and the effect of changes on airplane C are provided.

Note presenting a method for the rapid determination of design velocity diagrams of turbine stages within specified aerodynamic limits. The method is presented in both chart and tabular form.

Note presenting porcelain-enamel ground coats, which were prepared and applied under conditions that gave various degrees of adherence between enamel and a low-carbon steel. This study was primarily undertaken to find out additional information on the mechanism of adherence of porcelain-enamel ground coats to iron.

Note presenting results of an investigation of the fatigue strength of several full-scale aircraft wing structures. The 34 fatigue failures which resulted from the tests were of four main types and occurred in three principal localities on the test wings. Results regarding the definition of fatigue failure, load history of specimens, description of fatigue failures, spread in fatigue life, stress concentration factors, rate of crack growth, and effect of fatigue damage on natural frequency and damping are provided.

From Introduction: "This paper presents the basic design method and experimental results of calibration of a nozzle which was constructed to conform to the analytically determined ordinates."

"An approximate method for computing water loads and pressure distributions on lightly loaded elliptical cylinders during oblique water impacts is presented. The method is of special interest for the case of emergency water landings of helicopters. This method makes use of theory developed and checked for landing impacts of seaplanes having bottom cross sections of V and scalloped contours. An illustrative example is given to show typical results obtained from the use of the proposed method of computation" (p. 1).

From Introduction: "The purpose of this report is to treat analytically heat addition heat addition to a divergent stream with initially sonic flow and to employ the results thus obtained in evaluating the effect of delayed combustion on convergent-divergent nozzle performance."

Report presenting an experimental investigation to determine the effect of changes in shape of the rear fuselage of an airplane on ditching behavior. The behavior of the models was recorded with a high-speed camera, the records were analyzed, and the data is presented as curves of speed, attitude, and center-of-gravity height plotted against time.

Report presenting an analysis for optimum controllers of general, linear, time-invariant multiloop systems. General representations of controller characteristics, stable process characteristics, and error relations are used. General solutions are presented for four special cases.

Presents zero-lift drag data of an NACA RM-10 slender body of revolution with and without stabilizing fins attached. The results from several wind tunnels and in flight are compared. The results cover a Reynolds number range from about 1 time 10 to the 6th power to 40 times 10 to the 6th power for the flight models. The Mach numbers covered include 1.5 to 2.4 in the wind tunnels and 0.85 to 2.5 in flight.

"A study of the motion of a personal-owner or liaison airplane through the stall and into the incipient spin has been made by catapulting a dynamic model into still air. The results showed that the model became unstalled in inverted flight after its initial rotation of substantially 180 degrees in roll. Since the rates of rotation were low, it may be inferred that termination of the incipient spin would be most readily obtained by proper control movements at this point" (p. 1).

Report presenting an investigation to determine the effect of blade-section camber on the stall-flutter characteristics of three propellers using a 6000-horsepower propeller dynamometer. Up to a certain blade angle, there was an increase in flutter-speed coefficient with an increase in blade-section design lift coefficient. An increase in thrust was found to lead to an increase in tip Mach number in the flutter region of the propeller blades.

From Summary: "The general effect of wing sweep on cloud-droplet trajectories about swept wings of high aspect ratio moving at subsonic speeds is discussed. A method of computing droplet trajectories about yawed cylinders and swept wings is presented, and illustrative droplet trajectories are computed. A method of extending two-dimensional calculations of droplet impingement on nonswept wings to swept wings is presented."

Memorandum presenting a direct-connect duct investigation conducted with a one-quarter segment of a 25.5 inch diameter annular combustor which had been previously developed for liquid fuel injection. The combustor was modified by changing the fuel injectors and the liner design for vapor fuel injection. Results regarding accuracy and reproducibility, combustion efficiency, combustor-outlet temperature profiles, and pressure losses are provided.

Report presenting component performance data for one modification of a 16-stage compressor and a 3-stage turbine to determine the matched performance characteristics of an engine with those components. The compressor surge line and infinite exhaust-nozzle-area equilibrium operating line restricted the region of matched compressor-turbine operation. Results regarding the engine operation with modified compressor and three-stage turbine, effect of leakage on engine operation, component efficiencies, and operation in the surge region are provided.

Memorandum presenting the application of the concept of indicial functions to the analysis of the aerodynamic phenomena associated with the short-period pitching mode of wings in subsonic and supersonic flight. Simple physical relationships are pointed out and are used to study the effect on the rotary-damping-moment coefficient of changes in center-of-gravity position, Mach number, aspect ratio, plan form, frequency, and thickness.

Memorandum presenting testing of an experimental Custer Channel Wing airplane in the full-scale tunnel to investigate the lift characteristics of a channel-propeller combination and the flow phenomena in and about a channel wing.

Report presenting an investigation to determine the low-speed large-scale characteristics of an aspect ratio 3 triangular-wing airplane model. The model consisted of the wing in combination with a fuselage of fitness ratio 12.5, a thin, triangular vertical tail with a constant-chord rudder, and a thin, unswept, all-movable tail.

From Summary: "Calculated velocity and temperature distributions, as well as relations among Nusselt number, Reynolds number, and friction factor, are presented. The effect of variation of fluid properties across the tube on the Nusselt number and friction factor correlations can be eliminated by evaluating the properties at a reference temperature which is a function of both the wall temperature and the ratio of wall-to-bulk temperatures."

The structural damping in the torsion mode of vibration of a series of untwisted, laminated thin beams simulating propeller blades is presented. The number of lamination were varied, as well as the bonding material and the method of joining lamination. Application of the data to the calculation of the minimum flutter speed of thin propeller blades indicates that appreciable gains in the minimum flutter speed may be obtained for laminated blades using a Cycleweld bond.

Report presenting cold-flow free-flight tests at zero lift to investigate the possibility of flutter of simulated wing-ram-jet-nacelle configurations which were 1/9-scale models of the wing and ramjet nacelles of the Grumman XSSM-N-6a missile. Testing was performed on three different configurations. Results regarding Mach number, velocity, aerodynamic density, and flutter are provided.

Report presenting some equations that give the interference on the trailing-vortex system of a uniformly loaded finite-span wing in a circular tunnel containing partly open and partly closed walls, with special reference to symmetrical arrangements of the open and closed portions. Methods are given for extending the equations to include tunnel shapes other than circular.

From Summary: "An analytical method for calculating the aerodynamic loading on wing-tip-tank combinations in subsonic flow is developed by using a simple horseshoe vortex-image system for the case of the tank axis in the plane of the wing. An illustrative example is given in the appendix, in which wing and tip-tank loadings are calculated for three configurations. The calculated results are shown to be in good agreement with experimental data."

Memorandum presenting a rigorous expression for the slowing-down length of neutrons in hydrogenous media under the assumption that the nonhydrogen nuclei have infinite mass and that capture is absent. Two expressions have been applied to the same sample mixture, a uranium-235 and water mixture with the ratio of hydrogen to uranium nuclei chosen as 25.