National Advisory Committee for Aeronautics (NACA) - 193 Matching Results
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- Performance of B. M. W. 185-horsepower airplane engine
- Report discusses the results of testing on a B.M.W. engine in an altitude chamber where temperature and pressure can be controlled to simulate flight at various altitudes. Results for various engine speeds, altitudes, and propeller speeds are provided.
- Ditching investigation of a 1/25-scale model of a 255,000-pound transport airplane
- "An investigation was made of a 1/25-scale dynamically similar model of a 255,000-pound transport airplane in order to study its behavior when ditched. The model was free-launched from the Langley tank no. 2 monorail carriage into calm water. Various landing attitudes, flap settings, speeds, and configurations were investigated" (p. 1).
- The effect of blunt-trailing-edge elevons on the longitudinal and lateral handling qualities of the semitailless airplane
- Report presenting a flight program using the Northrop X-4 semitailless airplane to investigate the effect on the longitudinal and lateral stability and control of thickened elevons with trailing-edge thickness one-half the control-hinge-station thickness. The investigation consisted of speed runs, wind-up turns, abrupt rudder-fixed rolls, and longitudinal pulses between a range of Mach numbers.
- Stabilization of 50-Percent Magnesium - JP-4 Slurries With Some Aluminum Soaps of C(Sub 8) Acids
- Report presenting an exploratory investigation of three aluminum disoaps of C(sub 8) acids to determine the gelling properties and stabilizing ability in slurries of 50 percent magnesium power and JP-4 fuel. All of the soaps were found to gel the slurries satisfactorily and to exhibit adequate reproducibility of gel properties. Results regarding the soap behaviors, effects of temperature, viscosity, and formation of the gel structures are provided.
- Factors Affecting Lateral Stability and Controllability
- The effects on dynamic lateral stability and controllability of some of the important aerodynamic and mass characteristics are discussed and methods are presented for estimating the various stability parameters to be used in the calculation of the dynamic lateral stability of airplanes with swept and low-aspect-ratio wings.
- Evaluation of Gust and Draft Velocities From Flights of P-61C Airplanes Within Thunderstorms July 31, 1947 to August 6, 1947 at Clinton County Army Air Field, Ohio
- Memorandum presenting the results of measurements of gust and draft velocities within thunderstorms at an air field over a 7-day period. The data are summarized in tables and compared to previous flights.
- Analytical and experimental investigation of thrust augmentation of axial- and centrifugal-compressor turbojet engines by injection of water and alcohol in combustion chambers
- Report presenting an investigation of thrust augmentation by injection of water and water-alcohol mixtures in the combustion chambers at sea-level zero-ram flight conditions on 4000-pound-thrust axial-flow and centrifugal-flow turbojet engines. Thrust augmentation, compressor characteristics, fuel flow, and turbine-outlet-temperature distributions are presented for various injection rates and water-alcohol mixtures.
- Preliminary investigation of flow fluctuations during surge and blade row stall in axial-flow compressors
- "A preliminary investigation of the flow fluctuations of surge and blade row stall was conducted with three single-stage axial-flow compressors with hub-tip ratios of 0.9,0.8, and 0.5 and with a multistage axial-flow compressor. Flow fluctuations of large amplitude associated with stall were detected in all compressors investigated. The fluctuations were caused by low flow regions affecting 25 to 40 percent of the annulus area and propagating in the direction of compressor rotation, but at a lower speed. Mild audible surge was obtained with the single-stage compressors with hub-tip ratios of 0.9 and 0.8" (p. 1).
- Investigation of Interference, Lift, Drag, and Pitching Moment of a Series of Rectangular Wing and Body Combinations at Mach Numbers of 1.62, 1.93,and 2.41
- Report presenting an investigation of a series of rectangular wing and body combinations at Mach numbers 1.62, 1.93, and 2.41 to determine the effects of aspect ratio, incidence angle, and forebody length on the interference lift, drag, and pitching moment. A limited investigation to determine the effect of Reynolds number on the wings in the presence of the body was also carried out. Information regarding wing lift, basic quantities for interference evaluation, interference qualities, contributions of the various components, and the concept of wing-lift carry-over is provided.
- Theoretical Investigation of the Performance of Proportional Navigation Guidance Systems: Effect of Method of Positioning the Radar Antenna on the Speed of Response
- Memorandum presenting a linear theoretical analysis made of the performance of three proportional navigation guidance systems installed in a given supersonic, variable-incidence, boost-glide, antiaircraft missile at Mach numbers of 2.7 and 1.3. Three guidance systems are compared on the basis of the maximum obtainable speed of response of the missile and guidance-system combination consistent with adequate stability. Results regarding the effect of method of positioning the radar antenna on the speed of response, effect of Mach number on response, and effect of networks are provided.
- Thrust augmentation of a turbojet engine by the introduction of liquid ammonia into the compressor inlet
- Report presenting an experimental investigation to determine the thrust augmentation possible by the injection of liquid ammonia into the compressor inlet of an axial-flow-type turbojet engine. Results regarding the selection of coolant, cooling with liquid ammonia, engine performance, and operating experience are provided.
- Effect of oxygen concentration of the inlet oxygen-nitrogen mixture on the combustion efficiency of a single J33 turbojet combustor
- Report presenting an investigation to determine the importance of molecular-scale processes in the overall turbojet combustion process. The effect of oxygen concentration on the inlet oxygen-nitrogen mixture on the combustion efficiency of a single J33 combustor was determined for a range of combustor-inlet pressures and a range of fuel-flow rates. At a given fuel-flow rate, combustion efficiency decreased at an increasing rate with reduction in oxygen concentration.
- A Relation of Wind Shear and Insolation to the Turbulence Encountered by an Airplane in Clear-Air Flight at Low Altitudes
- Memorandum presenting the observed gust experience of an airplane and information on the associated meteorological conditions to obtain a simple empirical relation for estimating the intensity of turbulence in the earth's friction layer. The relation does not discriminate between differences in turbulence intensity resulting from variations of flight altitude or diurnal variations of turbulence.
- Effect of design changes and operating conditions on combustion and operational performance of a 28-inch diameter ram-jet engine
- The results of an altitude test-chamber investigation of the effects of a number of design changes and operating conditions on altitude peformance of a 28-inch diameter ram jet engine are presented. Most of the investigation was for a simulated flight Mach number of 2.0 above the tropopause. Fuel-air distribution, gutter width, the presence of a pilot flame, cimbustion-chamber-inlet temperature, and exhaust-nozzle throat area were found to have significant effects on limits of combustion. Combustion efficiency increased with increasing combustion-chamber-inlet temperature and was adversely affected by an increase in the exhaust-nozzld area. Similiar lean limits of combustion were obtained for both Diesel fuel and normal heptane, but combustion efficiences obtained with Diesel fuel were lower than those obtained with normal heptane.
- Effect of Magnitude of Vibratory Load Superimposed on Mean Tensile Load on Mechanism of and Time to Fracture of Specimens and Correlation to Engine Blade
- Memorandum presenting tensile fatigue tests run on seven turbine-blade alloys at a temperature of 1500 degrees Fahrenheit and a mean stress of 22,000 pounds per square inch with superimposed alternating stresses of 0, 5000, 10,000, and 15,000 pounds per square inch. The same three types of fracture occurring in turbine blades - stress-rupture, stress-rupture followed by fatigue, and fatigue - were obtained in the specimens. Results regarding the effect of alternating stress on mechanism of failure, specimen life, reduction of area of fractured specimens, and effect of specimen shape on life are provided.
- Internal performance of several types of jet-exit configurations for supersonic turbojet aircraft
- Investigation of the internal performance characteristics of several jet-exit configurations over a wide range of pressure ratios, which are summarized to provide an overall picture of jet-exit performance. The configurations investigated include a convergent nozzle, fixed convergent-divergent nozzles, an adjustable plug-type convergent-divergent nozzle, and jet ejectors. Results regarding the performance of several jet-exit configurations and matching adjustable jet exits to supersonic aircraft are provided.
- Effect of radiant energy on vaporization and combustion of liquid fuels
- Report presenting an investigation of the radiative processes involved in combustion to determine the present role of radiant energy transfer in combustors. The equivalent gray-body emissivity of a hydrocarbon fuel may be increased by use of liquid or solid, soluble or nonsoluble, additives. Results regarding the experimental apparatus and methods, emission characteristics of luminous and nonluminous flames, absorptivity of fuels and of solutions of possible additives, and absorption by slurries are provided.
- Performance characteristics of several types of axially symmetric nose inlets at Mach number 3.85
- Report presenting an experimental investigation conducted a Mach number of 3.85 to determine the diffuser characteristics of a series of conventional axially symmetric nose inlets on a ramjet in a supersonic wind tunnel. Performance evaluations of single-cone, double-cone, and isentropic diffusers were made in terms of total pressure recovery and mass flow for a range of angles of attack. Results regarding performance of 1-cone inlets, performance of 2-cone inlets, and performance of isentropic inlets are provided.
- Some observations of flow at the throat of a two-dimensional diffuser at a Mach number of 3.85
- Report presenting an experimental investigation at a Mach number of 3.85 in the supersonic wind tunnel to study the flow patterns at the throat of a two-dimensional single-shock diffuser and to evaluate qualitatively several schemes for improving the turning conditions. Schileren observations were made for supercritical inlet operation and conditions of maximum total-pressure recovery.
- An Investigation of Longitudinal Control Characteristics of a Wing-Tip Control Surface on a Sweptback Wing at Transonic Speeds by the NACA Wing-Flow Method
- Report presenting an investigation of the longitudinal control effectiveness of a full-chord wing-tip control surface on a wing with 35 degrees of sweepback, 12 percent thickness perpendicular to the quarter-chord line, an aspect ratio of 3.01, and a taper ratio of 0.605 at a range of Mach numbers. Wing-tip control was only 1/6 as effect in producing pitching moment at subsonic speeds as a flap type control and 1/2 as effect at low-supersonic speeds.
- Preliminary Investigation of the Transfer of Heat From a Flat Plate at a Mach Number of 1.5
- "Surface temperatures and heat transfer to the air stream have been measured for turbulent flow over a flat plate at a Mach number of 1.5 and at a Reynolds number, based on the momentum thickness of the boundary layer, of approximately 5000. Preliminary data are presented and the surface heat-transfer coefficients calculated from these data are considered to be accurate to plus or minus 2.6 percent at a temperature potential of 50 degrees Fahrenheit. These data are in good agreement with the results produced by applying modifications obtained from published information to existing subsonic theories" (p. 1).
- Wire cloth as porous material for transpiration-cooled walls
- The permeability characteristics and tensile strength of a porous material developed from stainless-steel corduroy wire cloth for use in transpiration-cooled walls where the primary stresses are in one direction were investigated. The results of this investigation are presented and compared with similar results obtained with porous sintered metal compacts. A much wider range of permeabilities is obtainable with the wire cloth than with the porous metal compacts considered and the ultimate tensile strength in the direction of the primary stresses for porous materials produced from three mesh sizes of wire cloth are from two to three times the ultimate tensile strengths of the porous metal compacts.
- Low-Speed Characteristics of a 45 Degree Swept Wing with Leading-Edge Inlets
- Memorandum presenting an investigation to determine the low-speed aerodynamic characteristics of a 45 degree swept wing with leading-edge inlets. The wing had a constant chord and completely spanned the wind tunnel. Results regarding surface-pressure characteristics, lift and pitching-moment characteristics, wake-drag characteristics, and internal-flow characteristics are provided.
- Effect of Section Thickness and Trailing-Edge Radius on the Performance of NACA 65-Series Compressor Blades in Cascade at Low Speeds
- Report presenting tests of NACA 65-series compressor blades cambered to an isolated airfoil lift coefficient of 1.2 at several maximum section thicknesses to obtain the effect of maximum section thickness on section operating characteristics. Information about surface pressure trends, design angle-of-attack selection, drag, operating range, and critical Mach number is also provided. Changing the section thickness was not found to significantly affect the design angle of attack selected.
- Aerodynamics of slender bodies at Mach number of 3.12 and Reynolds numbers from 2 x 10(exp 6) to 15 x 10(exp 6) 1: body of revolution with near-parabolic forebody and cylindrical afterbody
- An experimental investigation of the aerodynamic characteristics of a slender, square-based body of revolution was conducted at a Mach number of 3.12 for angles of attack from 0 degree to 10 degrees and for Reynolds numbers from 2 x 10(exp 6) to 15 x 10(exp 6). Boundary-layer measurements at zero angle of attack are compared with several compressible flow formulating for predicting boundary-layer characteristics. Comparison of experimental pressure and force values with theoretical values showed good agreement for low angles of attack. The measured mean skin-friction coefficients agreed well with those predicted by Mangler's transformation for laminar flow over cones.
- Preliminary Theoretical Investigation of Several Methods for Stabilizing the Lateral Motion of a High-Speed Fighter Airplane Towed by a Single Cable
- Report presenting a theoretical investigation of the lateral stability of a towed high-speed fighter plane using a fighter cruising at supersonic speed at 50,000 feet and a 1000-foot cable. The motion of this configuration was shown to have highly unstable oscillation caused by the towline restraint, but the configuration can be stabilized by choosing the right position for the towline connection and several types of automatic controls.
- Effect of liner air-entry holes, fuel state, and combustor size on performance of an annular turbojet combustor at low pressures and high air-flow rates
- Report presenting the development of an annular combustor by utilizing the design principles evolved in previous investigations and by making 12 design changes to optimize the altitude performance of the combustor. Three types of fuels were used and the combustion efficiency, pressure losses, and outlet temperature profiles were evaluated.
- Tests in the Ames 40- by 80-foot wind tunnel of an airplane configuration with an aspect ratio 3 triangular wing and an all-movable horizontal tail: Longitudinal and lateral characteristics
- Report presenting an investigation to determine the low-speed large-scale characteristics of an aspect ratio 3 triangular-wing airplane model. The model consisted of the wing in combination with a fuselage of fitness ratio 12.5, a thin, triangular vertical tail with a constant-chord rudder, and a thin, unswept, all-movable tail.
- Flight Determination of the Longitudinal Stability in Accelerated Maneuvers at Transonic Speeds for the Douglas D-558-II Research Airplane Including the Effects of an Outboard Wing Fence
- The results of transonic flight measurements of the longitudinal stability characteristics of the Douglas D-558-II research airplane in the original configuration and with outboard fences mounted on the wings are presented. The levels of normal-force coefficient at which the stability decreases and pitch-up starts have been determined for both airplane configurations at Mach numbers up to about 0.94.
- Preliminary Investigation of Several Root Designs for Cermet Turbine Blades in Turbojet Engine 2: Root Design Alterations
- Report presenting engine evaluation tests of twelve sets of cermet turbine blades. The first five runs were similar to previous engine tests, but the remaining ones were modified based on information gained during the first runs.
- Time-History Data of Maneuvers Performed by a Lockheed F-94B Airplane During Squadron Operational Training
- "Preliminary results of approximately 350 maneuvers of all types performed by a Lockheed F-94B jet interceptor airplane during normal operational training are presented in time-history form and are summarized as maximum load factors, control rates, angular accelerations, and sideslip angles plotted against indicated airspeed. The results were obtained from approximately 350 maneuvers performed by a Lockheed F-94B jet interceptor airplane during squadron operational training" (p. 1).
- An Investigation at Mach Numbers 2.98 and 2.18 of Axially Symmetric Free-Jet Diffusion with a Ram-Jet Engine
- "An investigation was conducted to determine the effectiveness of a free-jet diffuser in reducing the over-all pressure ratios required to operate a free jet with a large air-breathing engine as a test vehicle. Efficient operation of the free jet was determined with and without the considerations required for producing suitable engine-inlet flow conditions. A minimum operating pressure ration of 5.5 was attained with a ratio of nozzle-exit to engine-inlet area of 1.85" (p. 1).
- Analytical and experimental investigation of inlet-engine matching for turbojet-powered aircraft at Mach numbers up to 2.0
- An analysis of inlet-turbojet-engine matching for a range of Mach numbers up to 2.0 indicates large performance penalties when fixed-geometry inlets are used. Use of variable-geometry inlets, however, nearly eliminates th The analysis was confirmed experimentally by investigating at Mach numbers of 0, 0.63, and 1.5 to 2.0 two single oblique-shock-type inlets of different compression-ramp angles, which simulated a variable-geometry configuration. The experimental investigation indicated that total-pressure recoveries comparable withose attainable with well designed nose inlets were obtained with the side inlets when all the boundary layer ahead of the inlets was removed. Serious drag penalties resulted at a Mach number of 2.0 from the use of blunt-cowl leading edges. However, sharp-lip inlets produced large losses in thrust for the take-off condition. These thrust penalties which are associated with the the low-speed operation of the sharp-lip inlet designs can probably be avoided without impairing the supersonic performance of the inlet by the use of auxiliary inlets or blow-in doors.
- Preliminary investigation of combustion of diborane in a turbojet combustor
- Boron and its hydrides offer increased flight range relative to conventional fuels for turbojet engines. Preliminary evaluation has been made of the combustion characteristics and deposition problems resulting from burning diborone in a single, modified J33 combustor. A combustor relatively free of deposits for the limited test conditions has been developed. Three possible methods of alleviating deposits on the turbine blades are reported.
- Stability and control characteristics at low speed of a 1/10-scale model of MX-1554A design
- Report presenting an investigation of the low-speed stability and control characteristics of a scale model of the proposed MX-1554A design. It employs a triangular wing and triangular stabilizing surfaces. Results regarding the effect of wing incidence, tail position, fences, and chord extensions on the longitudinal characteristics are provided.
- Spontaneous Flammability of Pentaborane and Pentaborane-3-Methylpentane Blends
- Memorandum presenting a study of the spontaneous flammability of pentaborane and pentaborane-3-methylpentane blends. The behavior of the substances in air and in liquid and vapor states was studied. Results regarding conditions under which pentaborane did not ignite and conditions under which pentaborane did ignite are provided.
- Effect of Fuel-Air Ratio Concentration in Combustion Zone on Combustion Performance of a 16-Inch Ram-Jet Engine
- The results of fuel-air ratio and temperature surveys made in the flame stabilizing zone of a 16-inch ram-jet combustor indicated that the distribution of combustible mixture immediately downstream of a flame holder should be mechanically controlled if a preferred mixture composition is to be maintained in that zone. A sloping-baffle combustor configuration gave combustion efficiencies of 90 percent or greater over a range of fuel-air ratios from 0.010 to 0.045.
- Transonic free-flight investigation of the total drag and of the component drags (cowl pressure, additive, base, friction, and internal) encountered by a 16-inch-diameter ram-jet engine for Mach numbers from 0.80 to 1.43
- Report presenting an investigation of the drag on four full-scale models of 16-inch-diameter ramjet engines. The total, base, internal, and external drag were evaluated for each of the models. Results regarding the drag evaluations and drag comparison are provided.
- Application of Tchebichef form of harmonic analysis to the calculation of zero-lift wave drag of wing-body-tail combinations
- Report presenting an improvement of the computing procedure of NACA RM A53H17 using a new procedure of harmonic analysis using Tchebichef polynominals. The two main improvements are the simplification of computing procedures and the provision for a comprehensive check solution which includes a direct check of how well the number of harmonics used represent the area-distribution curve.
- Aerodynamics of bodies, wings, and wing-body combinations at high angles of attack and supersonic speeds
- From Introduction: "The primary purpose of this paper is to describe progress in the aerodynamics of wings, bodies, and wing-body combinations at high angles of attack."
- The Origin and Distribution of Supersonic Store Interference From Measurement of Individual Forces on Several Wing-Fuselage-Store Configurations 5: Swept-Wing Heavy-Bomber Configuration With Large Store (Nacelle). Mach Number 2.01
- Report presenting an investigation of store interference in the supersonic pressure tunnel at Mach number 2.01 in which separate forces on a store and a swept-wing-fuselage combination were measured. The interference effects measured at that Mach number were similar to those reported previously at Mach number 1.61. Results regarding store drag, store lift, store side force, store pitching moment and yawing moment, wing-fuselage drag, wing-fuselage lift, total drag, total lift, and wing-fuselage flow field are provided.
- Ignition of Ammonia and Mixed Oxides of Nitrogen in 200-Pound-Thrust Rocket Engines at 160 Degrees F
- Memorandum presenting a study of the ignition of ammonia and mixed oxides of nitrogen at 160 degrees Fahrenheit made with and without fuel additives utilizing small-scale rocket engines of approximately 200 pounds thrust. All experiments were conducted at sea-level pressures except two at a range of pressure altitudes. Results regarding the use of lithium as a catalyst, calcium as a catalyst, and no apparent catalyst are provided.
- Forced-convection heat-transfer and pressure-drop characteristics of a closely spaced wire matrix
- Memorandum presenting an investigation of the forced-convection heat-transfer and pressure-drop characteristics of a staggered closely spaced 0.020-inch wire metal-to-air heat exchanger. Eight wire banks were electrically heated, and the range of variables included bulk Reynolds numbers based on wire diameter and maximum velocity, from 82 to 1900, average wire temperatures up to 1109 degrees R, and heat flux densities up to 84,000 Btu per hour per square foot.
- Angle-of-attack-supersonic performance of a configuration consisting of a ramp-type scoop inlet located either on top or bottom of a body of revolution
- From Introduction: "In reference 1, in which the performance of conical supersonic scoop inlets on circular fuselages is reported, the drag of the bottom-inlet configuration was considerably higher than for the top inlet."
- Experimental performance of liquid fluorine-liquid ammonia propellant combination in 1000-pound-thrust rocket engines
- "The performance of liquid fluorine and liquid ammonia as a propellant combination was evaluated in 1000-pound-thrust rocket engines operated at a chamber pressure of 600 pounds per square inch absolute. Values of specific impulse, characteristic velocity, thrust coefficient, and heat rejection were obtained as functions of propellant mixture ratio for each of four injectors: a triplet, a showerhead, and two like-on-like types" (p. 1).
- Theoretical pressure distributions for some slender wing-body combinations at zero lift
- Report presenting pressure distributions calculated for some symmetrical wing-body combinations at zero lift. Of particular interest is the effect of indenting the body on the distribution of pressure over the wing.
- Wind-tunnel investigation at low speed of the yawing stability derivatives of a 1/10-scale model of the Douglas A4D-1 airplane: TED No. NACA DE 389
- Report presenting an experimental investigation to determine the low-speed yawing stability derivatives of a model of the Douglas A4D-1 airplane. The model was tested in clean and landing configurations with horizontal and vertical tails on and off. Results are provided without analysis.
- Longitudinal stability characteristics in maneuvering flight of the Convair XF-92A delta-wing airplane including the effects of wing fences
- Report presenting the longitudinal stability characteristics of the Convair XF-92A delta-wing airplane in maneuvering flight. The investigation included the determination of the characteristics of the basic airplane and the effects of two wing fence configurations on the characteristics.
- Flight measurements of the dynamical longitudinal stability and frequency-response characteristics of the XF-92A delta-wing airplane
- Report presenting dynamic longitudinal maneuvers over a range of Mach numbers at an altitude of 30,000 feet by utilizing the XF-92A delta-wing research airplane. An analysis of the dynamic responses was made with three approaches: measured period and time to damp, analogue computer simulation of the airplane time-response characteristics, and Fourier transformation. Results regarding period, time and cycles to damp, and stability derivatives with Mach number are provided.
- Flight Measurements of Elevon Hinge Moments on the XF-92A Delta-Wing Airplane
- Report presenting flight measurements of the elevon hinge moments on the Convair XF-92A delta-wing airplane over a range of Mach numbers during longitudinal elevon pulses, aileron rolls, and wind-up turns. During wind-up turns, the hinge moments become nonlinear at about the angle of attack at which the airplane experiences a marked decrease in longitudinal stability.