Report presenting drag coefficients determined by the accelerometer method for the Bell X-1 airplane with 8-percent-thick wing and 6-percent-thick tail in power-off flight over a range of Mach numbers and lift coefficients. Results regarding the variation of computed lift and drag coefficients, variation of lift coefficient with Mach number, and effect of Mach number on lift-drag ratio are provided.

Report presenting results and analysis of the longitudinal stability and control characteristics of the Douglas D-558-I airplane at a range of altitudes and Mach numbers. It was found that large and rapid changes in elevator deflection and force were required for balance at Mach numbers above 0.84 due to a sharp decrease in elevator-stabilizer effectiveness.

Report presenting visual observations and flow analyses made of annular liquid flow with cocurrent air flow in 2- and 4-inch-diameter horizontal transparent tubes. The experiments occurred over a range of air mass velocities, air temperatures, and Reynolds numbers. Results regarding the velocity and thickness of liquid films, description of water-film disturbances, effect of flow variables on liquid-film characteristics, and relation between disturbances and flow conditions are provided.

Report presenting a comparison of the calculated response characteristics corresponding to the maximum maneuver of a variable-incidence, a canard, and a conventional tail-aft-control, beam-rider, guided missile. All the configurations were designed to be the same except for the effects of changes in lift ratio. Results regarding limited control-surface deflection, limited angle of attack of the critical surface, servo energy, surface-deflection interference, and size of surfaces are provided.

Report presenting measurements of pressure made over the chord of a swept-wing model at four stations along the span by the NACA wing-flow method. The model was an untapered 45 degree sweptback wing of aspect ratio 3.5 with 2-inch-chord NACA 65-210 airfoil sections normal to the leading edge. Results regarding the chordwise pressure distributions and spanwise distributions of section lift, drag, and pitching moment.

Report presenting an investigation at low speed in the low-turbulence tunnel to determine the effects of variations in propeller-shank geometry and propeller-spinner-juncture configuration on the aerodynamic characteristics of an NACA 1-series cowling-spinner combination with an eight-blade dual-rotation propeller. Results regarding internal flow and external flow are provided.

"Values of total drag coefficient were measured for four round-nosed bodies of revolution in free flight at Mach numbers from 0.6 to 1.5 and Reynolds numbers from 10 x 10(6) to 50 x 10(6). The bodies were designed by rounding off the sharp, fineness-ratio-3.56 nose of a previously tested configuration. The nose radii tested were 27.4, 38.7, 80.6, and 100 percent of the maximum body radius and corresponded to values of 0.075, 0.150, 0.650, and 1.000, respectively, for the ratio of nose-sphere frontal area to body frontal area" (p. 1).

Report presenting a pilot-opinion survey conducted with a conventional fighter airplane fitted with special servo devices for varying in flight the dihedral effect, static directional stability, and directional damping. Results showing the boundaries that define satisfactory and tolerable lateral oscillatory characteristics are presented.

Memorandum presenting the pressure recovery, mass flow, and drag of a twin-scoop, side-inlet-body combination measured at Mach number 1.4 and 1.7. The inlet was located on a body having an ogival nose followed by a cylindrical section and a total fineness ratio of 5.

Memorandum presenting a systematic study to determine the effect of molecular structure on the flammability limits of pure hydrocarbon-air mixtures at reduced pressures and room temperature. This report presents results obtained for 17 pure normal paraffins, branched paraffins, and mono-olefins. Results regarding experimental variables and experimental observations are provided.

Memorandum presenting an investigation to evaluate the effect of Reynolds number and Mach number on the aerodynamic characteristics of a horizontal tail of aspect ratio 3 equipped with a plain, sealed, full-span elevator. The line joining the quarter-chord points of the airfoil sections was swept back 45 degrees and the sections perpendicular to this line were the NACA 64A010. Results regarding the effect of Reynolds number and effects of leading-edge roughness and elevator-nose seal are provided.

Memorandum presenting the pressure recovery, mass flow, and axial force of four bodies with nose inlets measured at Mach numbers between 1.4 and 2.0 and angles of attack of 0, 3, 6, and 9 degrees. The drag coefficients of axially symmetric diffusers operating at the maximum mass-flow rates were calculated from schileren photographs of the head shock waves and frictional drag considerations. Results regarding open-nose diffusers and conical-shock diffusers are provided.

Report presenting the effect on drag of varying the vertical position of a nacelle at 40 percent semispan of a 45 degree sweptback wing and body combination as determined by transonic flight tests at zero lift. Three nacelle positions were investigated: a pylon mounted nacelle, an underslung nacelle, and a symmetrically mounted nacelle. Results regarding total drag coefficient and maximum wing-tip helix angle are provided.

Three homologous series of related dicyclic hydrocarbons are presented for comparison on the basis of their physical properties, which include net heat of combustion, density, melting point, boiling point, and kinematic viscosity. The three series investigated include the 2-n-alkylbiphenyl, 2-n-alkylbicyclohexyl (high boiling), and 2-n-alkylbiphenyls (low boiling) series through c sub 16, in addition to three branched-chain (isopropyl, sec-butyl, and isobutyl) 2-alkylbiphenyls and their corresponding 2-alkylbicyclohexyls. The physical properties of the low-boiling and high-boiling isomers of 2-sec-butylbicyclohexyl and 2-isobutylbicyclohexyl are reported herein for the first time.

"A general method of design is developed for two-dimensional unbranched channels with prescribed velocities as a function of arc length along the channel walls. The method is developed for both compressible and incompressible, irrotational, nonviscous flow and applies to the design of elbows, diffusers, nozzles, and so forth. In part I solutions are obtained by relaxation methods; in part II solutions are obtained by a Green's function. Five numerical examples are given in part I including three elbow designs with the same prescribed velocity as a function of arc length along the channel walls but with incompressible, linearized compressible, and compressible flow" (p. 153).

A vector study of the partial-differential equation of steady linearized supersonic flow is presented. General expressions which relate the velocity potential in the stream to the conditions on the disturbing surfaces, are derived. In connection with these general expressions the concept of the finite part of an integral is discussed. A discussion of problems dealing with planar bodies is given and the conditions for the solution to be unique are investigated. Problems concerning nonplanar systems are investigated, and methods are derived for the solution of some simple nonplanar bodies. The surface pressure distribution and the damping in roll are found for rolling tails consisting of four, six, and eight rectangular fins for the Mach number range where the region of interference between adjacent fins does not affect the fin tips.