Report presents the results of an investigation of full-scale nose-slot cowlings conducted in the NACA 20-foot wind tunnel to furnish information on the pressure drop available for cooling. Engine conductances from 0 to 0.12 and exit-slot conductances from 0 to 0.30 were covered. Two basic nose shapes were tested to determine the effect of the radius of curvature of the nose contour; the nose shape with the smaller radius of curvature gave the higher pressure drop across the engine. The best axial location of the slot for low-speed operation was found to be in the region of maximum negative pressure for the basic shape for the particular operating condition. The effect of the pressure operating condition on the available cooling pressure is shown.

An aid in airplane design, charts have been prepared to show the effects of wing taper, thickness ratio, and Reynolds number on the spanwise location of the initial stalling point. Means of improving poor stalling characteristics resulting from certain combinations of the variables have also been considered; additional figures illustrate the influence of camber increase to the wing tips, washout, central sharp leading edges, and wing-tip slots on the stalling characteristics. Data are included from which the drag increases resulting from the use of these means can be computed. The application of the data to a specific problem is illustrated by an example.

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.

Report discussing tests of the drag clean-up and stability of the Bell YP-59A jet-propelled airplane. The general stability, static stability, and control characteristics were examined. Specific details are also included about the effects of the exhaust jet on air flow at the tail.

Introduction: "The ionization region in the Nier mass spectrometer is customarily constructed of copper. Various other metals were tried for this purpose; among them tantalum and molybdenum, with both metals it was found that a spectrum of the fluoride of the metal appeared when uranium hexafluoride was admitted. It was thus possible to produce tantalum fluoride with comparative ease and to make a critical examination of the mass spectrum to set an upper limit of abundance of tantalum isotopes. For positive identification, a line must appear in all ion positions in the same abundance, relative to the main line. It must be shown that any lines which appear are not contributed by other elements or compounds."

Historical: This process is based on experimental work done in Jackson Laboratory, Send Works, Blue Products, and East Area. It supersedes the Tentative Chambers Works Process for the Manufacture of Fluorine Using Carbon Anode Units, dated December 2, 1943.

A method is developed whereby the fundamental mechanisms are investigated by which processing, heat treatment, and chemical composition control the properties of alloys at high temperatures. The method used metallographic examination -- both optical and electronic --studies of x-ray diffraction-line widths, intensities, and lattice parameters, and hardness surveys to evaluate fundamental structural conditions. Mechanical properties at high temperatures are then measured and correlated with these measured structural conditions. In accordance with this method, a study was made of the fundamental mechanism by which aging controlled the short-time creep and rupture properties of solution-treated low-carbon n-155 alloy at 1200 degrees F.

Three graphs representing the four series of isotopes.

An investigation was conducted on an 0.08-scale semispan model of the Chance Vought XF7U-1 airplane in the Langley high-speed 7- by 10-foot tunnel in the Mach number range from 0.40 to 0.97. The results are compared with those obtained with an 0.08-scale sting-mounted complete model tested in the same tunnel and with an 0.026-scale semispan model tested by the wing-flow method. The lift-curve slopes obtained for the 0.08-scale semispan model and the 0.026-scale wing-flow model were in good agreement but both were generally lower than the values obtained for the sting model.

Contains results of calculations made to determine the neutral oscillatory stability boundaries, period and time to damp of the oscillatory mode, and motions following disturbances. The calculations were made for Mach numbers of 0.75 and 2.3 at an attitude of 35,000 feet and for the landing condition at sea level.

Report presenting a wind-tunnel investigation at low speed to determine the lateral control characteristics of a 51.3 degree sweptback-wing model equipped with either plain or stepped spoiler ailerons with a fixed projection of 5-percent-wing chord and various spans and spanwise locations. The results indicated that spanwise rolling-effectiveness charts of flap-type ailerons can not be used to predict effectiveness of spoiler-type ailerons on swept wings. Results regarding the wing aerodynamic characteristics with spoiler ailerons retracted, wing aerodynamic characteristics with spoiler ailerons projected, and a comparison of spoiler-type and flap-type ailerons.

Report presenting the effectiveness of a 50-percent-semispan, constant-percent-chord elevon, and of upper-space spoilers as lateral control surfaces for a wing-fuselage combination with a wing swept back 63 degrees over a range of Mach numbers. For the elevon, results indicated that only about half of the predicted rolling-moment effectiveness was realized. The spoilers were found to be inferior to the elevons for lateral control because of a rapid loss of effectivness above an angle of attack of 4 degrees.

Memorandum presenting several new methods that have been designed for obtaining electrical connection to thermocouples that are revolving at high speeds. Two general types of pickup system are described with modifications for special installations. Both pickup systems have been proved to transmit an accurate signal from a revolving thermocouple to within 0.045 millivolt at contact sliding speeds up to 5400 feet per minute.

From Abstract: "The report is concerned with a theoretical analysis of the experiment known as the Calibration of the 3" Cross Control Rod. The experiment provided 29 points on a curve of reactivity (in hours per centimeter) versus depth of control rod insertion. An attempt to reproduce this curve theoretically has been quite successful."

This technical report presents "a theoretical study of the motion of gas bubbles in a rotating liquid" in order to "make comparison with experimental data from an investigation concerning the removal of gas bubbles from rotating liquids as descriped in ORNL-630." The report presents a literature review of "motion of gas bubbles in liquids" and provides a "summary of extensive experimental studies at the University of Tennessee." It also presents "an expression for the radial velocity of a gas bubble in a rotating liquid based on principles of mechanics." Finally, this report presents "a method for computing the steady state state [sic] gas hold-up in the HRE reactor core under power producing conditions." (From introduction)

Report presenting a flight investigation conducted on a 35 degree swept-wing fighter airplane with two different horizontal-tail heights. The longitudinal stability and buffet characteristics were compared for the two configurations. Results regarding longitudinal stability, buffet, and pitch-up intensity are provided.

The basic ideas of the slender-body approximation have been applied to the nonlinear transonic-flow equation for the velocity potential in order to obtain some of the essential features of slender-body theory at transonic speeds. The results of the investigation are presented from a unified point of view which demonstrates the similarity of slender-body solutions in the various Mach number ranges. The transonic area rule and some conditions concerning its validity follow from the analysis. (author).

At the request of the Bureau of Aeronautics, Department of the Navy, National Advisory Committee for Aeronautics has conducted a preliminary investigation at high subsonic speeds of the static longitudinal and lateral stability characteristics of a 0.05-scale model of the Convair F2Y-1 water-based fighter airplane. The tests covered a Mach number range from 0.5 to 0.94 and corresponding Reynolds numbers, based on the wing mean aerodynamic chord, from 3.3 x 10(exp 6) to 4.3 x 10(exp 6). The maximum angle-of-attack range (obtained at the lower Mach numbers) was from -2 degrees to 25 degrees. Sideslip angles from -4 degrees to 12 degrees also were investigated. The investigation included effects of various arrangements of wing fences and of rocket packages.

Report presents information about free-flight rocket-propelled model testing to determine the effect of some wing geometry variables on low lift drag at a range of Mach numbers. Results regarding the effect of airfoil section, wing nose droop and nose flaps, plan form, and wing vertical position are provided.

A two-etchant surface preparation treatment has been found which insures good adhesion between the zirconium and the nickel or copper electroplate. The etching process requires 1 1/2 minutes.

Memorandum presenting the effectiveness of a body flare as a pitch-stabilizing device and a body flap as a pitch-control device investigated experimentally at Mach numbers from 3.00 to 6.25. The basic test body was rotationally symmetric and consisted of a fineness ratio 3 nose followed by a fineness ratio 9 afterbody. Results regarding the stability of the flared body, effect of body flap on lift and drag, trim conditions, flow visualization studies, and comparison of theory and experiment are provided.

An investigation of the effectiveness of a body flare as a pitch-stabilizing device and a body flap as a pitch-control device over a range of Mach numbers. Experimentally defined increments in lift and drag due to flap deflection are compared at Mach number 5 with the predictions of generalized shock-expansion theory and Newtonian impact theory. Results regarding the stability of the flared body, effect of body flap on lift and drag, trim conditions, flow visualization studies, and a comparison of theory and experiment are provided.

"A two-dimensional investigation utilizing pressure-distribution measurements and schileren photographs has been made of the flow and force characteristics of slab-sided airfoils of 2-percent thickness at transonic Mach numbers. The airfoils had various combinations of elliptically shaped leading and trailing edges from a fineness ratio of 0 to 10. The aerodynamic characteristics and an analysis of the flow past the models are presented" (p. 1).

Pressure distributions were measured over rectangular wings of aspect ratio 2 and triangular wings of aspect ratios 2 and 4 at Mach numbers of 2.46 and 3.36. The investigation includes some comparison of the effects of Mach number, Reynolds number, and thickening the wing root sections on the loading.