Memorandum presenting an exploratory investigation to determine the aerodynamic effects of camber on a 60 degree apex delta-wing model conducted in the 300 mph 7- by 10-foot tunnel. Camber variation was accomplished through the deflection of full-span round and 25 degree beveled leading-edge flaps on a flat-sided triangular plan-form wing.

Report presenting an investigation of the experimental performance of chlorine triflouride and hydrazine measured over a range of propellant mixtures in a 100-pound-thrust rocket engine. Experimental values of specific impulse, volume specific impulse, heat rejection per propellant weight, nozzle thrust coefficient, and characteristic velocity were obtained as functions of percent fuel by weight in the propellant mixture.

Report presenting a flight investigation of rocket-powered models at high-subsonic, transonic, and supersonic speeds to determine the zero-lift drag of fin-stabilized bodies of revolution differing in maximum diameter. All bodies had 6.04 fineness ratio and cut-off sterns with equal base area. The most favorable location out of the 20-percent, 40-percent, and 60-percent positions were evaluated for different speeds.

Report presenting the results of flight tests showing lateral oscillation in the Bell X-1 and calculations created to determine the effects of changes in several mass and aerodynamic parameters on the lateral oscillations. Calculations indicate that lateral stability should be improved by a more positive inclination of the principal axis of inertia or a reduction of the value of yawing moment of inertia.

Report presenting an approximate method for calculating the interference pressure distribution at zero lift of a symmetrical sweptback wing mounted on a circular cylindrical body with the chord plane of the wing passing through the axis of the body. An example is provided using a circular cylindrical body and an untapered wing with 60 degrees of sweepback.

Report presenting an investigation of a series of flame holders designed with the objective of providing a high combustion efficiency in a ramjet combustor at an inlet air velocity of 200 feet per second, inlet-air pressure of 60 inches of mercury absolute, inlet air temperature of 200 degrees Fahrenheit, and near stoichiometric fuel-air ratio. Results regarding the preliminary experiments, two parallel rows of gutters, three rows of gutters, staggered gutters, simultaneous use of three rows and staggered gutters, use of molybdenum, and magnitude of pressure fluctuations are provided.

Report presenting data from 95 subsonic flutter tests conducted in the flutter research tunnel on untapered cantilever wings with sweepback angles of 0, 45, and 60 degrees and carrying a single concentrated weight. The primary purpose of the investigation was to present experimental information to be used to evaluate analytical procedures for determining the flutter speed of weighted sweptback wings. The dynamic pressure, flutter velocity, Mach number, natural and flutter frequencies, and phase-angle relationships of the stresses for the natural and flutter frequencies are presented.

Report presenting wind-tunnel testing to determine the independent effects of Mach and Reynolds numbers on the aerodynamic characteristics of a wing-fuselage combination with a wing with the leading edge swept back 63 degrees and with camber and twist. Results regarding the fuselage alone and the effects of camber and twist are also provided.

Report presenting an investigation of the effect of hull length-beam ratio on the hydrodynamic characteristics of flying boats that extend to a length-beam ratio of 20. The results are compared with flying boats having a length-beam ratio of 15. Results regarding longitudinal stability, spray characteristics, take-off performance, taxiing and take-off behavior in waves, landing behavior in waves, and a summary chart are provided.

Report presenting an analysis of the dynamic-lateral-stability characteristics of the Bell X-2 airplane as affected by variations in mass, aerodynamic, and dimensional parameters by means of calculations of the period and rate of damping of the lateral oscillation. Results regarding the airplane with flaps and gear retracted, airplane with flaps and gear lowered, and effects of assumed modifications to the airplane are provided.

"This paper presents some data on the dynamic lateral stability characteristics of the Douglas D-558-II (BuAero No. 37974) airplane. For the airplane in the clean condition, the lateral oscillations are lightly damped. In the landing condition, the airplane performs a constant-amplitude lateral oscillation" (p. 1).

"Abrupt rudder-fixed aileron rolls have been made with the Bell X-1 airplane in powered flight at Mach numbers between 0.90 and 1.06 at about 40,000 feet pressure altitude. These aileron rolls indicate that the aileron effectiveness for large deflections at Mach number 0.94 is only one-fourth the value at Mach number 0.82, and the effectiveness at Mach number 1.06 is slightly greater than at Mach number 0.94" (p. 1).

From Introduction: "An analysis of eddy currents in a compressor blade, the geometry of which has been limited to that of a flat plate for simplicity, is presented."

"NACA instrumentation has been installed in the Northrop X-4 airplane to obtain stability and control data during the Northrop conducted acceptance tests. The results of the fourth and fifth flights of the Northrop X-4 number 1 airplane are presented in this paper. These data were obtained for a center-of-gravity position of approximately 19.5 percent of the mean aerodynamic chord. The results of this flight showed that the directional stability as measured in steadily increasing sideslips was positive and high and that the effective dihedral was positive. The results also show the airplane to be longitudinally stable, stick fixed, with the center of gravity at 19.5 percent of the mean aerodynamic chord" (p. 1).

Report presenting aerodynamic and icing investigations in the icing research tunnel on a model of a turbojet-engine nacelle with a short straight air inlet. The hot-gas blowback system consisted of several orifices peripherally located around the inlet and was investigated in both dry-air and icing conditions. Results regarding the aerodynamic investigation without bleedback, aerodynamic investigation with cold-gas bleedback, aerodynamic investigation with hot-gas bleedback, and icing with bleedback are provided.

Report discussing an investigation to determine the effect of sweepback on the static and rolling stability derivatives of a series of wings with a taper ratio of 0.6 and an aspect ratio of 4. The influence on the straight-flow characteristics, rolling-flow characteristics, and aileron characteristics are provided.

Report presenting an investigation to determine the damping-in-roll characteristics of a 42.7 degree sweptback wing using a linearly twisted wing to represent a rolling wing. Results regarding the effect of the airfoil contour, damping-in-roll coefficient, wing-tip helix angle, and theoretical results are provided.

Report presenting the results of an experimental investigation to determine the pressure-recovery and mass-flow characteristics of single and twin NACA submerged intakes on the sides of a fuselage at various angles of sideslip. Tests were conducted with single and twin submerged intakes on a model of a fighter-type airplane.

Memorandum presenting measurements made in the transonic speed ranges of the static-pressure position error at a distance of 0.96 chord ahead of the wing tip of both the 8-percent-thick-wing and the 10-percent-thick-wing X-1 airplanes, and at a point 0.6 maximum fuselage diameter ahead of the fuselage nose of the X-1 airplanes. Results regarding the accuracy of pitot-static heads, static-pressure error of wing-tip installation, static-pressure error of the fuselage-nose installation, and error in total pressure are provided.

Ignition studies of flowing gases were made to obtain information applicable to ignition problems in gas-turbine and ram-jet aircraft propulsion systems operating at altitude conditions.Spark energies required for ignition of a flowing propane-air mixture were determined for pressure of 2 to 4 inches mercury absolute, gas velocities of 5.0 to 54.2 feet per second, fuel-air ratios of 0.0607 to 0.1245, and spark durations of 1.5 to 24,400 microseconds. The results showed that at a pressure of 3 inches mercury absolute the minimum energy required for ignition occurred at fuel-air ratios of 0.08 to 0.095. The energy required for ignition increased almost linearly with increasing gas velocity. Shortening the spark duration from approximately 25,000 to 125 microseconds decreased the amount of energy required for ignition. A spark produced by the discharge of a condenser directly into the spark gap and having a duration of 1.5 microseconds required ignition energies larger than most of the long-duration sparks.

A supplementary investigation on the stabilization of the Jettisonable nose section of the X-2 airplane has been conducted in the Langley 20-foot free-spinning tunnel. It was found that the nose section could be stabilized by the addition of curved fins which could be folded against the fuselage for normal flight.

"A single-stage modification of the turbine from a Mark 25 torpedo power plant was investigated to determine the performance with two nozzle designs in combination with special rotor blades having a 20 inlet angle. The performance is presented in terms of blade, rotor, and brake efficiency as a function of blade-jet speed ratio for pressure ratios of 8, 15 (design), and 20. The blade efficiency with the nozzle having circular pas- sages (K) was equal to or higher than that with the nozzle having rectangular passages (J) for all pressure ratios and speeds investigated" (p. 1).

"As part of the performance investigation of compressors for the J33 turbojet engine, the A-21 model and the A-23 model with a 17- and a 34-blade impeller were operated with water injection at their respective design equivalent speeds of 11,500 and 11,750 rpm. Inlet conditions of pressure of 14 inches of mercury absolute and of ambient temperature correspond to those of the investigation of these models without water injection. The water-air ratio by weight ranged from 0.05 to 0.06. By the use of water injection, the peak pressure ratio of the A-21 compressor and the A-23 compressor with a 34-blade impeller increased approximately 0.38, whereas that of the A-23 compressor with a 17-blade impeller increased only 0.14" (p. 1).

A vane-type angle-of-attack indicator suitable for measurements at both subsonic and supersonic speeds has been developed by the National Advisory Committee for Aeronautics. A brief history is given of the development, and a wind-tunnel calibration of the indicator is presented, together with a discussion of the corrections to be applied to the indicated readings.