Formulas, computer program, and illustrations for a great circle path at ionospheric heights.

We undertook the present diffraction study of the bifluoride ion in sodium acid fluoride and the present refinement of the earlier data on potassium acid fluoride with the hope of obtaining more accurate information not only on the position of the hydrogen atom, but also on the vibrations of the ion. We felt that it would be through the combination of information on the motions of the system from diffraction and spectroscopic studies that the question of the symmetry of the ion could be settled. In this paper we summarize briefly the results of our diffraction study and show that these data, in combination with the spectroscopic data, provide new, and we feel convincing, evidence that the F-H-F ion is linear and symmetric.

A pool of material in steady-state turnover is a collection of identical molecules from which deletions are made at a constant rate, along with simultaneous addition of new identical molecules at the same rate, the total pool size remaining unchanged. It is of interest to consider what may be expected in the way of such pools among the various chemical species which can be isolated from biological systems. It is clear what the model requires, i.e. any molecule belonging to the pool must have as much chance as any other pool molecule to make its exit. This situation is approximated by molecules in solution in a well mixed volume of fluid, hence the choice of the word "pool." The mixing brings pool molecules into proximity with the exit mechanism in a random way.

A stimulation study of the deign as of June 1960 of the gas-cooled ORR Loop No. 1 was made using the ORNL analog computer. The proposed method of temperature control is evaluated, and the dynamic behavior of the loop for accidents and component failures is presented in graphical form.

Abstract: A definitive investigation of the boron-carbon equilibrium system is being made by X-ray diffraction, metallographic, and thermal analytical techniques. Additional baron-carbon alloys have been prepared by sintering and arc-melting compacts prepared from boron and high-purity graphite. Metallographic examinations of these alloys are in agreement with alloys previously preapred from lampblack. X-ray investigation of sintered compacts indicates that the solubility range of boron carbide extends almost to pure boron. Boron of various purities has been annealed for times up to four hours, but no structure other than beta-rhombohedral has been detected. Very high purity boron (10 ppm impurity) has been obtained for the study of allotropy and the equilibrium relationships at very dilute carbon contents.

Abstract: "As part of a program entitled "Improved Zirconium Alloys" a brief summary of a present zirconium research at various organizations has been prepared. Information was obtained by telephone and personnel contact; and these discussions, along with the organization and personnel, are presented."

An experiment has been performed using nuclear emulsions to measure the neutron flux and energy spectrum from a thick uranium target bombarded by 18-Mev electrons. The total integrated flux of 3.6 x 10(-4) neutrons/electron found here is considerably lower than the figure reported by other investigators. We attribute this discrepancy primarily to a wandering of the electron beam. The neutron spectrum should be unaffected. In addition to the expected peak at 1 Mev the energy spectrum shows a secondary peak at about 5 Mev. The shape of the experimental spectrum excluding this secondary peak, is fitted theoretically by a combination of the "evaporative" and "resonance direct" effects.

A modification of the Bridgeman anvils is described. This modification permits studies to be made to a load of 400 kbars, about twice that previously available.

Report discussing tests performed with a rocket-boosted model of the McDonnell F4H-1 airplane at transonic and supersonic speeds. Special attention is given to the external drag coefficient at various Mach numbers. Large pitching oscillations were also noted at Mach numbers between 0.20 and 1.17, which made it impossible to determine the drag at that range.

From Summary: "A flight test was conducted with a 0.13-scale rocket-boosted model of the McDonnell F4H-1 airplane configuration at transonic and supersonic speeds. The external drag coefficient varied from a value of 0.044 at a Mach number of 1.17 to 0.045 at a Mach number of 1.40 and then decreased to 0.041 at a Mach number of 1.90. The limited oscillatory data available indicate the existence of a coupled longitudinal-lateral motion in the Mach number range from 0.20 to 1.17."

"An investigation has been made at Mach numbers of 1.61 and 2.01 and Reynolds numbers of 1.7 x l0(exp 6) and 3.6 x l0(exp 6) to determine the pressure distributions over a swept wing with a series of 14 control configurations. The wing had 40 deg of sweep of the quarter-chord line, an aspect ratio of 3.1, and a taper ratio of 0.4. Measurements were made at angles of attack from 0 deg to +/- 15 deg for control deflections from -60 deg to 60 deg. This report contains tabulated pressure data for the complete range of test conditions" (p. 1).

Report presenting an investigation in the 16-foot transonic tunnel to determine the effects of leading-edge droop on the pressure distribution on a 45 degree sweptback wing with an aspect ratio of 4, a taper ratio of 0.6, and NACA 65A006 airfoil sections parallel to the plane of symmetry. Results regarding the chordwise pressure distributions, wing-panel characteristics, wing-section characteristics, and maximum additional normal load on wing leading edge are provided.

Report presenting a supersonic flight investigation of a roll-stabilized acceleration control missile for a Mach number range from 1.4 to 1.7. The control system operation was found to be satisfactory and applicable to some present-day missiles using linear acceleration commands. Results regarding analysis, preflight simulator results, a comparison between simulator and analytical results, flight test results, and a comparison between the flight test and preflight simulator results are presented.

A high-solidity low-aspect-ratio transonic rotor with an inlet hub-tip ratio of 0.52 was investigated experimentally. The rotor developed a total-pressure tatio of 1.93 and an efficiency of 92 percent at an equivalent wheel tip speed of 1036 feet per second. The feasibility of using this rotor as a component of an inlet stage of an axial-flow compressor was investigated.

In the reference document, a statistical method for analyzing run to rupture tests involving two metal types, a test material and a control standard, is presented. It often happens that more than two metal types are involved in a production test. In this document, the statistical procedure recommended for this situation is presented.

A survey of unclassified axial-flow-compressor literature is presented in the form of brief reviews of the methods, results, and conclusions of selected reports. The reports are organized into several main categories with subdivisions, and frequent references are made within the individual reviews to pertinent material elsewhere in the survey.

Report presenting an investigation in the transonic tunnel to determine the effects of adding external, pylon-suspended stores to a model of the Douglas D-558-II research airplane. Tests were made for two spanwise store locations and covered a range of angles of attack and Mach numbers. Results regarding the drag, lift, and pitching-moment characteristics are provided.

In tests of a portable tank specially designed and constructed under Air Force Contract AF 33(616)-2229, liquid fluorine was safely transported and stored. The investigation included 82 hours of transportation in a total storage time of 2570 hours.

"The transonic longitudinal aerodynamic characteristics of a 0.0858-scale model of the Lockheed XF-104 airplane have been obtained from tests at the Langley 16-foot transonic tunnel. The results of the investigation provide some general information applicable to the transonic properties of thin, low-aspect-ratio, unswept wing configurations utilizing a high horizontal tail . The model employs a horizontal tail mounted at the top of the vertical tail and a wing with an aspect ratio of 2.5, a taper ratio of 0.385, and 3.4-percent-thick airfoil sections" (p. 1).

Report presenting an investigation to measure the flying qualities of a high-performance personal-owner airplane to investigate the possible causes of instrument flying accidents with that type of aircraft. Testing indicated that the lack of aerodynamic stall warning and rapid roll-off at the stall could contribute to stall-spin accidents with high-performance personal-owner aircraft. Results regarding the handling qualities and the control under instrument flying conditions are provided.

The following quarterly report covers the period of July through September of 1950, split into three reports discussing the metabolic properties of plutonium and allied materials, biological studies of radiation effects, and health chemistry and physics.

Report presenting a wind-tunnel investigation to determine propeller section aerodynamic characteristics by measuring surface pressure distribution on the airfoil sections of a rotating propeller. The pressures were measured at nine radial sections of the NACA 10-(3)(08)-03 two-blade propeller. Results regarding sectional critical Mach number, and aerodynamic coefficients are also presented.

From Summary: "An investigation of turbojet-engine thrust augmentation by means of tail-pipe burning has been conducted in the NACA Lewis altitude wind tunnel. Several fuel systems and flame holders were investigated in a 29-inch-diameter tail-pipe burner to determine the effect of fuel distribution and flame-holder design on tail-pipe-burner performance and operational characteristics over a range of simulated flight conditions. At an altitude of 5000 feet, the type of flame holder used had only a slight effect on the combustion efficiency."

Report presenting an investigation of the characteristics of a low-aspect-ratio wing at high subsonic Mach numbers in the high-speed tunnel. The wing model had an NACA 65-108 airfoil section, an aspect ratio of 4.01, a taper ratio of 0.498, and no twist or dihedral. Results regarding normal-force characteristics, pitching-moment characteristics, and drag characteristics are provided.