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open access

The effect of compressibility on two-dimensional tunnel-wall interference for a symmetrical airfoil

Description: Summary: The effective change in the velocity of flow past a wing section, caused by the presence of wind-tunnel walls, is known for potential flow. This theory is extended by investigation of the two-dimensional compressible flow past a thin Rankine Oval. It is shown that for a symmetrical section at zero angle of attack the velocity increment due to the tunnel walls in the incompressible case must be multiplied by the factor 1/1-M^2 to take account of compressibility effects. The Mach numb… more
Date: May 1943
Creator: Nitzberg, Gerald E.
open access

Emergency Measures for Increasing the Range of Fighter Airplanes

Description: "An analysis was made to show the relative effectiveness of streamline external fuel tanks, a fuel tank in the form of a wing mounted in a biplane position, and auxiliary wing panels attached at the wing tips to increase the span as temporary means for increasing the range of a fighter-type airplane. Figures and charts for the various devices considered show the results of calculations of range, duration of flight, and take-off distance for both land-base and carrier operation. The results indi… more
Date: May 1943
Creator: Jones, Robert T. & Wetmore, Joseph W.
open access

Good pastures.

Description: A guide to improving pastures for the purpose of increasing production during wartime.
Date: May 1943
Creator: Semple, Arthur T. (Arthur Truman), 1895- & Hein, M. A. (Mason August), b. 1894

Newsmap. Monday, May 17, 1943 : week of May 7 to May 14, 192nd week of the war, 74th week of U.S. participation

Description: Front: Text describes action on various war fronts: North Africa, Southwest Pacific, China-Burma, Plans, Aleutians, Russia Large world map is keyed to text and shows United Nations, Axis and Axis occupied areas, countries with Axis relations broken, and neutral countries. Inset maps: Shrinking battle lines in Tunisia; Crimea and surrounding region showing Nazi held territories. Photographs: Army-Navy expedition lands at Amchitka; Army gunner sets up AA defense at the westernmost U.S. air ba… more
Date: May 17, 1943
Creator: [United States.] Army Orientation Course.

Newsmap. Monday, May 10, 1943 : week of April 30 to May 7, 191st week of the war, 73rd week of U.S. participation

Description: Front: Text describes action on various war fronts: Tunisia, Command, Russia, Southwest Pacific, China, Air offensive. Special illustrated section describes clearing mine fields in Tunisia. Large world map is keyed to text and shows United Nations, Axis and Axis occupied areas, countries with Axis relations broken, and neutral countries. Inset maps: Tunisia. Photographs: Planes wait to be ferried by barge to land; Convoy of Allied ships steam toward an Arctic port; Army trucks yield to air… more
Date: May 10, 1943
Creator: [United States.] Army Orientation Course.
open access

Metallurgical Laboratory, Chemical Research - Radiation Chemistry, Report for the Month Ending May 15, 1943

Description: Technical report that information has bee obtained on the effect of beta and gamma radiation on the electrical resistance of insulating materials The results are summarized. The recovery to original resistance values has been measured. In general, the initial rate is rapid for the first few hours; the rate then decreases sharply. Certain samples show evidence of complete recovery. Effects on mechanical properties of several plastics has also been studied. Data on gas evolution from severa… more
Date: May 15, 1943
Creator: Franck, J.
open access

The Effect of Fast Fission on k

Description: The importance of fast neutron fission (i.e., fission caused by neutrons before being slowed down) was recognized by Szilard, and calculations similar to the present one have already been carried out by him, Feld, Ashkin, Wheeler, Wigner and others. The purpose of the present paper is to give a general formula for the contribution of fast fission to the multiplication constant, which will include all the cases already considered and will be applicable to more complicated geometries than those c… more
Date: May 4, 1943
Creator: Castle, H.; Ibser, H.; Sacher, G. & Weinberg, Alvin Martin, 1915-2006
open access

Production of (Uranium) Tetrafluoride

Description: Production of tetrafluoride for the month of April was 49,400. New equipment installed late in March operated smoothly and the production was slightly over the rated capacity of the plant. Nickel ends were welded on to the steel reactor tubes to prevent corrosion at the cover joint and possible contamination of the product with iron. The nickel ends will also save considerable repair work on the tube ends. The magnesium trays for some of the reactors are beginning to crack at the sides from fre… more
Date: May 13, 1943
Creator: Long, K. E. & Swinehart, C. F.
open access

Full-scale tunnel investigation of the pressure distribution over the tail of the P-47B airplane

Description: Report presenting measurements made of the pressures of the tail surfaces of the Republic Aviation Corporation P-47B airplane in the full-scale tunnel. Pressures were measured over the horizontal and vertical tail surfaces for several angles of attack and angles of yaw with numerous control-surface deflections to provide a check on the design loads. Results regarding the normal-force coefficients and predictions of forces on horizontal tail surfaces are provided.
Date: May 1943
Creator: Dingeldein, Richard C.
open access

Shear Tests on DuPont Explosive Rivets With the Countersunk Head Milled Flush After Expansion

Description: Report discusses the results of shear testing in which the heads of Du Pont explosive countersunk rivets were allowed to protrude above the skin surface before expansion and the protruding portions were removed after expansion. As the height of the rivet head above the skin increases, the tightness of the rivet was found to increase. The report concludes that it may be desirable to investigating filling an entire shank with an explosive charge in order to permit greater tolerances in the drille… more
Date: May 1943
Creator: Gottlieb, Robert & Bartone, Leonard M.
open access

Method of Calculating Performance of Dual-Rotating Propellers From Airfoil Characteristics

Description: "A method is developed for calculating the performance of a dual-rotating propeller from the section characteristics of the blade elements. The method is applied to an eight-blade dual-rotating propeller and the computed results are compared with low-speed wind-tunnel tests of the same propeller in both the tractor and pusher positions. The computations are found to agree within the experimental accuracy of the measurements" (p. 1).
Date: May 1943
Creator: Naiman, Irven
open access

Least-Work Analysis of the Problem of Shear Lag in Box Beams

Description: The distribution of stress in the cover sheets of thin-wall box beams is analyzed, with regard to the effect of shear deformation in the cover sheets, by the method of least work. Explicit results are obtained for a number of representative cases that show the influence of the following factors on the stress patterns. General conclusions are drawn from the results obtained. Among them the most important one appears to be the fact that the shear-lag effect depends primarily on several tow qualit… more
Date: May 1943
Creator: Hildebrand, Francis B. & Reissner, Eric
open access

Large-Deflection Theory of Curved Sheet

Description: Equations are given for the elastic behavior of initially curved sheets in which the deflections are not small in comparison with the thickness, but at the same time small enough to justify the use of simplified formulas for curvature. These equations are solved for the case of a sheet with circular cylindrical shape simply supported along two edges parallel to the axis of the generating cylinder. Numerical results are given for three values of the curvature and for three ratios of buckle lengt… more
Date: May 1943
Creator: Levy, Samuel
open access

Some Effects of Reynolds and Mach Numbers on the Lift of an NACA 0012 Rectangular Wing in the NACA 19-Foot Pressure Tunnel

Description: Bulletin presenting a short investigation in the 19-foot pressure tunnel to determine the aerodynamic characteristics of a rectangular wing model constructed to NACA 0012 airfoil sections. Tests were run with the air in the tunnel at 2 different pressures: atmospheric and 35 pounds per square inch absolute.
Date: May 1943
Creator: Muse, Thomas C.
open access

Effect of Powered Propellers on the Aerodynamic Characteristics and the Porpoising Stability of a Dynamic Model of a Long-Range Flying Boat

Description: Report discusses the results of two tests: "1) aerodynamic tests to determine the effect of the slipstream and thrust from the powered propellers on the lift and trimming-moment characteristics, and 2) hydrodynamic tests to determine the effect of the powered propellers on the range of stable locations of the center of gravity (from Introduction)." Large differences in the stable range between half-thrust and full-thrust conditions were observed. Three effects of power were also involved in the… more
Date: May 1943
Creator: Land, Norman S.
open access

Jet-boundary corrections for reflection-plane models in rectangular wind tunnels

Description: Report presenting a detailed method for determining the jet-boundary corrections for reflection-plane models in rectangular wind tunnels. The principal effects of aerodynamic induction and boundary-induced curvature of the streamlines are considered. An example is included to illustrate the method.
Date: May 1943
Creator: Swanson, Robert S. & Toll, Thomas A.
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