Search Results

open access

Chain Reaction of Pure Fissionable Materials in Solution

Description: The critical mass of 94-239 and the corresponding critical dimensions of homogeneous mixtures of 94-239 with various moderating media been calculated as a function of the concentration of 94. A simple transformation makes the figures applicated to92-235. the results are in essential agreement with the preliminary estimated made independently by Oppenheimer and Serber. The problem of the stability of a chain reaction in solution and questions of protection are discussed.
Date: January 1, 1943
Creator: Christy, Robert F., 1916-2012 & Wheeler, John Archibald, 1911-2008
Partner: UNT Libraries Government Documents Department
open access

Derivation of charts for determining the horizontal tail load variation with any elevator motion

Description: Report presenting equations relating the wing and tail loads are derived for a unit elevator displacement. The equations are converted into a nondimensoinal form and charts are given that can be used to predict wing- and tail-load-increment variation for any type of elevator motion and for degrees of airplane stability.
Date: January 1943
Creator: Pearson, Henry A.
Partner: UNT Libraries Government Documents Department
open access

Icing Tests of Aircraft-Engine Induction Systems

Description: Report presenting a program of icing tests conducted on an aircraft-engine induction system consisting of a Wright R-1820, G-200 blower section, Holley 1375-F carburetor and adapter, and specially built air scoop. The primary purpose of the investigation was to determine the effect of a number of possible factors on icing of engine-induction systems, including carburetor-air temperature, air-moisture content, water-droplet size, throttle opening, mixture ratio, rate of air flow, altitude, and o… more
Date: January 1943
Creator: Kimball, Leo B.
Partner: UNT Libraries Government Documents Department
open access

Use of Wetting Agents in Reducing Dust Produced by Wet Drilling in Basalt

Description: Report issued by the U.S. Bureau of Mines on wet-drilling tests using two different wetting agents. Amounts are listed in the results. This report includes tables, and illustrations.
Date: January 1943
Creator: Johnson, John A.
Partner: UNT Libraries Government Documents Department
open access

Wind Tunnel Investigation of Control-Surface Characteristics 11: Various Large Overhang and Internal-Type Aerodynamic Balances for a Straight- Contour Flap on the NACA 0015 Airfoil

Description: Report presenting force-test measurements in two-dimensional flow in the 4- by 6-foot vertical tunnel to determine the characteristics of several different shaped overhang-type aerodynamic balances applied to a straight-contour flap mounted on an NACA 0015 airfoil. The flap with blunt-nose overhang was overbalanced throughout certain ranges of flap deflection. Results regarding precision, lift, flap hinge moments, pitching moment, and drag are provided.
Date: January 1943
Creator: Sears, Richard I. & Hoggard, H. Page, Jr.
Partner: UNT Libraries Government Documents Department
open access

Wind Tunnel Investigation of Control Surface Characteristics: [Part] 12 - Various Cover-Plate Alinements on the NACA 0015 Airfoil With a 30 Percent Chord Flap and Large Sealed Internal Balance

Description: Report presenting force-test measurements in two-dimensional flow made in the 4- by 6-foot vertical tunnel to determine the aerodynamic effects of changing the alignment of the cover plates on a sealed internally balanced flap. Manufacturing imperfections in the alignment of the cover plates with the airfoil contour may have serious effects on the resultant hinge moment of a flap with a sealed internal balance. Results regarding lift, flap hinge moments, pitching moment, and drag are provided.
Date: January 1943
Creator: Hoggard, H. Page, Jr.
Partner: UNT Libraries Government Documents Department
open access

Theory and preliminary flight tests of an all-movable vertical tail surface

Description: Report presenting flight testing of an improved type of all-movable tail surface. The particular arrangement tested provides control-free stability and a stable variation of the control forces during maneuvers. Results regarding rudder effectiveness, directional stability, rudder-free lateral motion, and rudder-free turns are provided.
Date: January 1943
Creator: Jones, Robert T. & Kleckner, Harold F.
Partner: UNT Libraries Government Documents Department
open access

Wind-Tunnel Investigation of a Plain Aileron with Various Trailing-Edge Modifications on a Tapered Wing 3: Ailerons with Simple and Spring-Linked Balancing Tabs

Description: Aerodynamics data are obtained for the design of linked balancing tabs and effect of varied tab span and location to produce suitable lateral control characteristics with reasonable stick pressures for high-speed aircraft. Simple and spring-linked balancing tabs may considerably reduce control pressures if aileron system is designed for low maximum aileron deflection. Spring-linked tabs also decrease variation of stick pressure with speed and impart better controlllability at low speeds.
Date: January 1943
Creator: Purser, Paul E. & Rogallo, F. M.
Partner: UNT Libraries Government Documents Department
open access

Wind-tunnel investigation of a plain aileron with thickened and beveled trailing edges on a tapered low-drag wing

Description: Report presenting an investigation in the 7- by 10-foot tunnel of various modifications of the trailing-edge portion of a 0.20-chord plain aileron on a partial-span model of a tapered low-drag wing. The modifications tested included various amounts of symmetrical and unsymmetrical thickening and beveling of the aileron trailing edge. Results regarding coefficients and corrections, characteristics with ailerons neutral, characteristics with ailerons deflected, aileron trim characteristics, and e… more
Date: January 1943
Creator: Purser, Paul E. & McKee, John W.
Partner: UNT Libraries Government Documents Department
open access

Wind-tunnel investigation of profile drag and lift of an intermediate wing section of the XP-51 airplane with beveled trailing-edge and contour ailerons

Description: Report presenting the results of flight investigations showing that a beveled trailing-edge aileron gives as low or a lower profile drag than a contour aileron. Section profile drag and lift coefficients with two different types of ailerons were obtained at 3 different Reynolds numbers.
Date: January 1943
Creator: Abbott, Frank T., Jr. & Underwood, William J.
Partner: UNT Libraries Government Documents Department
open access

The significance of the time concept in engine detonation

Description: Report presenting an experimental technique developed by means of which the variables affecting the time element in the detonation process in a spark-ignition engine can be controlled and approximately measured. Results indicated that higher maximum permissible pressures can be used if the rate of compression of the end gas is increased. Suggestions for future study are provided.
Date: January 1943
Creator: Leary, W. A. & Taylor, E. S.
Partner: UNT Libraries Government Documents Department
open access

An experimental survey of flow across banks of elliptical and pointed tubes

Description: Report presenting an experimental survey of the details of the flow of fluids across banks of streamline tubes as a continuation of previous work. Information that clarifies the picture of flow has been obtained by surveys of total, dynamic, and static pressure, and hot-wire cooling surveys of the unheated tubes.
Date: January 1943
Creator: Joyner, Upshur T. & Palmer, Carl B.
Partner: UNT Libraries Government Documents Department
open access

General free to trim tests in NACA tank no.2 of three 1/8-full-size models of flying-boat hulls at low speeds-NACA models 116E-3K, 120R, and 143

Description: Report presenting tests of representative models of flying boat hulls to determine the resistance at low speeds. Results regarding the effect of load coefficients, resistance coefficients, and towing and drifting calculations are provided.
Date: January 1943
Creator: Carter, Arthur W.
Partner: UNT Libraries Government Documents Department
open access

The Effect of Amphibious Floats on the Power-Off Stability and Control Characteristics of a Twin-Engine Cargo Airplane

Description: Report presenting power-off wind tunnel tests of a scale model of a twin-engine cargo airplane equipped with amphibious floats. Longitudinal and lateral stability and control characteristics were investigated for three flap positions.
Date: January 18, 1943
Creator: Belsley, Steven E. & Jackson, Roy P.
Partner: UNT Libraries Government Documents Department
open access

Comparison of various methods for computing drag from wake surveys

Description: "The various equations for computing profile drag by the momentum method are examined, and the errors arising from complete or partial neglect of compressibility effects in the Jones equation and the Bicknell equation are evaluated. The integrating method of Silverstein and Katzoff is shown to be accurate over a wide range of Mach number and wake shapes" (p. 1).
Date: January 1943
Creator: Davis, Wallace F.
Partner: UNT Libraries Government Documents Department
open access

The Effect on Stability and Control of a Pusher Propeller Behind Conventional Tail Surfaces as Determined by Tests of a Powered Model in the Free-Flight Tunnel

Description: Report presenting an investigation of the effects on stability and control of a pusher propeller behind conventional horizontal and vertical tail surfaces in the free-flight tunnel by tests of a scale model of a submerged-engine pusher airplane. The investigation consisted of flight and balance tests at windmilling and high-power conditions with a partial-span Zap extensible flap extended and retracted. Results regarding the longitudinal stability, longitudinal control, stalling characteristics… more
Date: January 1943
Creator: Campbell, John P. & Hollingworth, Thomas A.
Partner: UNT Libraries Government Documents Department
open access

A preliminary study of the effect of compressive load on the fairness of a low-drag wing specimen with Z-section stiffeners

Description: "A low-drag airfoil specimen was loaded in compression, and surveys of the fairness of the surface were made at different stresses as well as at zero load after successively higher stresses had been applied and removed. The tests reported and the discussion of the significance of the results obtained suggest a procedure for determining the probable outcome of a particular type of construction for a low-drag wing" (p. 1).
Date: January 1943
Creator: Jacobs, Eastman N.; Lundquist, Eugene E.; Davidson, Milton & Houbolt, John C.
Partner: UNT Libraries Government Documents Department
open access

Additional design charts relating to the stalling of tapered wings

Description: From Introduction: "The present report, therefore, may be considered a supplement to reference 1. The combined scope of the stall charts of reference 1, designated A, and of the present work, designated B, is summarized in the following table: For the wing with root thickness ratio to 18 was also investigated.
Date: January 1943
Creator: Harmon, Sidney M.
Partner: UNT Libraries Government Documents Department
open access

Flight Investigation of NACA D(Sub S) Cowlings on the XP-42 Airplane 1: High-Inlet-Velocity Cowling with Propeller Cuffs Tested in High-Speed Level Flight

Description: Report presenting results from a series of flight tests of the maximum speed and cooling characteristics in full-throttle level flight of the XP-42 airplane equipped with a short-nose high-inlet velocity cowling. The results of the tests indicated a maximum speed of 336 miles per hour at 960 horsepower at 25,000 feet. Results regarding maximum speed and pressure and temperatures are provided.
Date: January 1943
Creator: Bailey, F. J., Jr.
Partner: UNT Libraries Government Documents Department
open access

Flight investigation of NACA D(sub S) cowlings on the XP-42 airplane 3: low-inlet-velocity cowling without fan or propeller cuffs, with axial-flow fan alone, and with two different sets of propeller cuffs

Description: Report presenting the results of flight measurements of performance and cooling characteristics of the XP-42 airplane equipped with a short-nose low-inlet-velocity cowling. Testing included measurements in level flight and climb of the effects of a spinner-mounted axial-flow fan without propeller cuffs, no fan or cuffs, and two different sets of propeller cuffs.
Date: January 1943
Creator: Johnston, J. Ford & Voglewede, T. J.
Partner: UNT Libraries Government Documents Department
open access

Flight investigation of NACA D(sub S) cowlings on the XP-42 airplane 4: high-inlet-velocity cowling tested in climb with and without propeller cuffs and in high-speed level flight without propeller cuffs

Description: Report presenting flight measurements of the performance and cooling characteristics of a short-nose high-inlet-velocity cowling on the XP-42 for conditions of climb with and without propeller cuffs and for high speed without cuffs. The speed of the airplane was approximately 1 mile per hour greater without propeller cuffs than the previously measured value with cuffs. Results regarding maximum speed, pressures and temperatures, and ground cooling are provided.
Date: January 1943
Creator: Johnston, J. Ford & Voglewede, T. J.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen