Report presenting a method for predicting the amplitude and frequency, under certain simplifying conditions, of the hunting oscillations of an automatically controlled aircraft with lag in the control system or in response of the aircraft to the controls. Formulas are given expressing the response to a variation of signal in terms of response to a unit signal.

"The results of flight investigations of the profile drag of several carefully finished conventional and low-drag airfoils are presented. The results indicated that in all cases lower profile-drag coefficients were obtained with the low-drag than with the conventional airfoils over the range of lift coefficient tested and that, for comparable conditions of lift coefficient and Reynolds number, the low-drag airfoils may have profile-drag coefficients which are at least 27 percent lower than the profile-drag coefficients of the conventional airfoils" (p.1).

Describes the mission, organization, and principles of employment of the field artillery unit.

This report contains work summaries for the week of May 18th, 1944 at the Hanford Atomic Products Operation. Canning, stack gas disposal, and graphite testing are discussed. (JL)

This report is a copy of a letter sent on May 23, 1944, concerning the analytical evaluation of Columbia River water by Clinton Laboratories.

This document contains information about the sampling program at Columbia River during May 5, 1944. Topics discussed include: securing representative samples; analysis of the samples looking at temperature, bacteriological content, dissolved oxygen, and physical tests; and the method and equipment used in the sampling procedure.

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This document provides the analytical reports on the aluminum-silicon alloy, tin and copper analytical reports are also provided.

It is usual to determine the density of neutrons by using foils of metals which become radioactive as a result of bombardment in the region under investigation. From the rate of disintegration of the newly formed radioactive element the number of neutrons absorbed can be calculated. By use of the capture cross section of the element of which the foil is composed the density of the neutrons can then be computed. By counting the alpha particles from a bismuth foil of known weight after exposure to neutrons the density of the neutrons which produced this activity can be calculated. The least accurately known value which enters into this evaluation is the capture cross-section of bismuth for pile neutrons. This value may be improved by future measurements. It is of importance only for absolute measurements of neutron density so that relative values can be measured with considerable accuracy on the basis of known data.

Abstract: "The advantages of high scaling ratios in counting random pulses are discussed. The mechanism of the basic circuit used in the Columbia University scaling circuits is described. The difficulties experienced in the performance of the earlier circuits are indicated and modified circuits to eliminate these difficulties are given. Precautions that must be observed in carrying out the constructional details are suggested. The complete circuit and specifications are given in detail for a Scale of 128 for use with linear-amplifier systems" (p. 1).

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Report discusses the results of testing to determine the maximum rates of control stick (elevator) motion and corresponding maximum stick forces that could be exerted based on experiments with several pilots. The main topics explored were the comparison of the maximum rates of push and pull, maximum rates of push and pull when a mental restriction was placed on the pilot, and maximum rates at which the pilot though he would apply the elevator control forces versus the actual application of forces. Information about experimental procedures and the rig the testing occurred on is included.

From Introduction: "The present paper deals with control surfaces having plain-overhang and Frise balances."

Report discusses an analysis and preliminary design of a control linkage that varies automatically with dynamic pressure. The advantages of the device, including greater lateral control than a fixed control linkage without additional aerodynamic balance, are detailed. The effect of variable linkage on lateral-control characteristics is also described.

From Introduction: "As a part of the general lateral-control investigation by the NACA, the large amount of two- and three-dimensional data on the rolling effectiveness of ailerons without exposed overhang balance is collected and analyzed in the present paper."

Report presenting methods for estimating pressure distributions over protuberances such as cockpit canopies, gun turrets, blisters, scoops, and sighting domes. The methods are applied to the estimation of the pressure distributions over spherical segment and faired gun turrets and over the protuberances on the Brewster SB2A-1 airplane. The effects of compressibility, interference, and flow separation are discussed.

"The effects of changes in aileron rigging between 2 deg up and 2 deg down on the stick forces were determined from wind-tunnel data for a finite-span wing model. These effects were investigated for ailerons deflecting equally in both directions and linearly with stick deflection. Data were analyzed for a Frise, a sealed internally balanced, and a beveled-trailing-edge aileron" (p. 1).

A step-by-step guide to making a dress at home, using a commercial home sewing pattern and woven fabric.

A guide to growing green onions from sets, in order to increase production and alleviate a wartime onion shortage.

From Summary: "The results of an analytical investigation to determine the qualitative effects of elevator-fabric distortion on the stick-force characteristics of an airplane are presented. These results indicate that serious alteration of intended stick-force characteristics can be produced by elevator-fabric distortion."

From Summary: "A method is outlined for determining in flight the weight rate of air flow to the engine equipped with a Bendix-Stromberg injection-type carburetor. The method has the advantage that no additional equipment need be inserted in the charge-air system and only a few simple measurements are necessary. The analysis of an air-box calibration of the carburetor to be used in interpreting the flight measurements is shown by an example."

From Summary: "This paper deals with the single problem if circular shell-supported frames subjected to concentrated loadings. A mathematical attack is developed and presented in the form of nondimensional-coefficient curves."

Field measurements were made on a fighter airplane to determine the approximate magnitude of the horizontal tail loads in accelerated flight. In these flight measurements, pressures at a few points were used as an index of the tail loads by correlating these pressures with complete pressure-distribution data obtained in the NACA full-scale tunnel. In addition, strain gages and motion pictures of tail deflections were used to explore the general nature and order of magnitude of fluctuating tail loads in accelerated stalls.