"An investigation has been undertaken on two dynamic models simulating 1/20-scale and 1/25-scale models of propeller-driven tail-sitter vertically rising airplanes to determine the altitude required to approach normal-flight conditions after power failure in hovering flight. The results of the investigation indicated that, for the two models investigated, an altitude of 3,600 to 5,400 feet may be required to attain normal gliding flight" (p. 1).

The three papers collected here are: 'The Effect of Nose Shape on the Drag of Bodies of Revolution at Zero Angle of Attack.', 'Base Pressure on Wings and Bodies with Turbulent Boundary Layers', and 'Flow over Inclined Bodies'. The subject of the first paper is the drag of the nose section of bodies of revolution at zero angle of attack. The main object of the second paper is to summarize the prinicpal results of the many wind tunnel and free flight measurements of base pressure on both bodies of revolution and blunt trailing edge airfoils.

From Summary: "An experimental investigation was made to determine the permeability and strength characteristics of a number of sintered, porous, hollow turbine rotor blades and to determine the effectiveness of the blade fabrication method on permeability control. The test blades were fabricated by the American Electro Metal Corporation under a contract with the Office of Naval Research, Department of the Navy, and were submitted to the NACA for testing. Of the 22 test blades submitted, ten were sintered but not coined, five were sintered and coined, and seven were sintered and not coined but contained perforated reinforcements integral with the blade shells. Representative samples of each group of blades were tested."

Review of certain characteristics necessary to determine skin friction and heat transfer on the surfaces of high-speed missiles, including temperature recovery, skin-friction coefficients and heat-transfer coefficients of laminar and turbulent boundary layers, and the position of the transition from laminar to turbulent flow. A comparison is also made between existing flight data and results computed by the boundary-layer momentum-integral method in an attempt to establish design criteria for missiles that are very different from the typical shape.

A flight investigation was made at high subsonic, transonic, and supersonic speeds and at high Reynolds numbers to determine the zero-lift drag of a 1/10-scale model of the Northrop MX-775A missile and a scale model of the missile fuselage. The model of the complete configuration has a 45deg swept wing of aspect ratio 5.5 and a 33deg swept vertical fin. The body model was stabilized by three 45deg swept fins. The-drag-rise Mach number for the model of the complete configuration was approximately 0.96. The drag coefficient based on total wing area was 0.0330 at Mach number 1.39. The drag coefficient of the body model less fin drag was approximately 55 percent that of the complete model at the same Mach number. Addition of the wing to the fuselage apparently resulted in a favorable drag interference near Mach number 1.0.

A flight test of a rocket-propelled model of the Convair XFY-1 airplane was conducted to determine the lateral stability and control characteristics, The 0.133-scale model had windmilling propellers for this test, which covered a Mach number range of O.70 to 1.12. The center of gravity was located at 13.9 percent of the mean aerodynamic chord. The methods of analysis included both a solution by vector diagrams and simple one- and two-degree-of-freedom methods. The model was both statically and dynamically stable throughout the speed range of the testa The roll damping was good, and the slope of the side-force curve varied little with speed. The rudder was effective throughout the test speed range, although it was reduced to about 43 percent of its subsonic value at supersonic speeds.

Technical report with short articles on (1) Uranium-oxygen system compositions UO2 to U3O3; (2) Thorium hydride; (3) Production of cerium; and (4) Production of thorium.

Two methods were developed for the determination of uranium metal in UF3 with other fluoride compounds. A simplified method of determination which has a relatively high degree of precision (coefficient of variation 2 per cent) is carried out by decomposing the hydride in an atmosphere of carbon dioxide and subsequently measuring the hydrogen over an aqueous solution of potassium hydroxide. The ignition of the hydride in an atmosphere of oxygen and volumetric measurement of the water at reduced pressures provide a more sensitive method of determination. The coefficient of variation of the latter procedure is 7 per cent. The yield of gas from the reaction of the hydride with ammonia and gaseous hydrogen chloride was found to be neither stoichiometric nor reproducible.

The purpose of the test was to determine the direction and magnitude of any drift in the temperature sensing elements and the receiver-indicating units for the primary loop and pressurizer resistance thermometers. To obtain intercalibration data for various temperature sensing elements in the primary coolant system. To obtain data on the difference between the calculated signal generated by the BF-3 counters, considering the known rate of decay of the PO-BE source, and the measured values. Determination of temperature sensing element and instrumentation drifts could not be made due to a lack of comparative data. Five temperature intercalibrations were performed using the calibrating Tc resistance thermometers as a standard. The data obtained from the nuclear instrumentation was too erratic to form any conclusions.

The purpose of the test was to determine the direction and magnitude of any drift in the temperature sensing elements and the receiver-indicating units for the primary loop and pressurizer resistance thermometers. To obtain intercalibration data for various temperature sensing elements in the primary coolant system. To obtain data on the difference between the calculated signal generated by the BF-3 counters, considering the known rate of decay of the PO-BE source, and the measured values. Of the 62 core thermocouples observed 19 were either reading less than 400 F or were reading in excess of 20 F from the calibrating thermometer temperatures. In each case the thermocouple was considered defective. The remainder were within 2 per cent of the calibrating thermometers. The primary loop (Norwood Indicators) resistance thermometers all read with 0.2 percent of the calibrating thermometers. No conclusion could be made for the pressurizer temperature instruments or the boiler Tb resistance thermometers, except that the 1A boiler temperature varied 10 F to 20 F from the 1Band 1C boiler temperatures. A laboratory calibration of this instrument will be made. The data obtained from the source range nuclear instrumentation was too erratic to form any conclusion. No drift evaluation on …