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An 8-foot axisymmetrical fixed nozzle for subsonic Mach numbers up to 0.99 and for a supersonic Mach number of 1.2
From Introduction: "This paper, which should be of interest to those concerned with transonic wind tunnels, covers the design and operating characteristics of the nozzle."
Ability of pilots to control simulated short-period yawing oscillations
No Description Available.
Abstracts pertaining to seaplanes
Report discussing about 400 references pertaining to the hydrodynamic design of seaplanes have been compiled, and the information is presented in the form of abstracts classified under six main headings.
Acceleration characteristics of a turbojet engine with variable-position inlet guide vanes
No Description Available.
Acceleration Characteristics of R-3350 Engine Equipped with NACA Injection Impeller
Qualitative investigations have shown that use of the NACA injection impeller with the R-3350 engine increases the inertia of the fuel-injection system and, when the standard fuel-metering system is used, this increase in inertia results in poor engine acceleration characteristics. This investigation was therefore undertaken to determine whether satisfactory acceleration characteristics of the engine equipped with the injection impeller could be obtained by simple modifications to the fuel-monitoring system. The engine was operated with two types of carburetor; namely, a hydraulic-metering carburetor incorporating a vacuum-operated accelerating pump and a direct-metering carburetor having a throttle-actuated accelerating pump. The vacuum-operated accelerating pump of the hydraulic-metering carburetor was modified to produce satisfactory accelerations by supplementing the standard air chamber with an additional 75-cubic spring. The throttle-actuated accelerating pump of the direct-metering carburetor was modified to produce satisfactory accelerations by replacing the standard 0.028-inch-diameter bleed in the load-compensator balance line with a smaller bleed of 0.0225-inch diameter. The results of this investigation indicated that both carburetors can be easily modified to produce satisfactory acceleration characteristics of the engine and no definite choice between the types of carburetor and accelerating pump can be made. Use of the direct-metering carburetor, however, probably resulted in better fuel distribution to the cylinders during the acceleration period and reduced the backfire hazard because all the fuel is introduced through the injection impeller.
Acceleration Measurements During Landing in Rough Water of a 1/7-Scale Dynamic Model of Grumman XJR2F-1 Amphibian - Langley Tank Model 212, TED No. NACA 2378
Tests of a 1/7 size model of the Grumman XJR2F-1 amphibian were made in Langley tank no.1 to examine the landing behavior in rough water and to measure the normal and angular accelerations experienced by the model during these landings. All landings were made normal to the direction of wave advance, a condition assumed to produce the greatest accelerations. Wave heights of 4.4 and 8.0 inches (2.5 and 4.7 ft, full size) were used in the tests and the wave lengths were varied between 10 and 50 feet (70 and 350 ft, full size). Maximum normal accelerations of about 6.5g were obtained in 4.4 inch waves and 8.5g were obtained in 8.0 inch waves. A maximum angular acceleration corresponding to 16 radians per second per second, full size, was obtained in the higher waves. The data indicate that the airplane will experience its greatest accelerations when landing in waves of about 20 feet (140 ft, full size) in length.
Acceleration Measurements During Landings of a 1/5.5-Size Dynamic Model of the Columbia XJL-1 Amphibian in Smooth Water and in Waves: Langley Tank Model 208M, TED No. NACA 2336
A 1/5.5-size powered dynamic model of the Columbia XJL-1 amphibian was landed in Langley tank no. 1 in smooth water and in oncoming waves of heights from 2.1 feet to 6.4 feet (full-size) and lengths from 50 feet to 264 feet (full-size). The motions and the vertical accelerations of the model were continuously recorded. The greatest vertical acceleration measured during the smooth-water landings was 3.1g. During landings in rough water the greatest vertical acceleration measured was 15.4g, for a landing in 6.4-foot by 165-foot waves. The impact accelerations increased with increase in wave height and, in general, decreased with increase in wave length. During the landings in waves the model bounced into the air at stalled attitudes at speeds below flying speed. The model trimmed up to the mechanical trim stop (20 deg) during landings in waves of heights greater than 2.0 feet. Solid water came over the bow and damaged the propeller during one landing in 6.4-foot waves. The vertical acceleration coefficients at first impact from the tank tests of a 1/5.5-size model were in fair agreement with data obtained at the Langley impact basin during tests of a 1/2-size model of the hull.
Acceleration of high-pressure-ratio single-spool turbojet engine as determined from component performance characteristics : effect of compressor interstage air bleed
No Description Available.
Acceleration of high-pressure-ratio single-spool turbojet engine as determined from component performance characteristics I : effect of air bleed at compressor outlet
An analytical investigation was made to determine from component performance characteristics the effect of air bleed at the compressor outlet on the acceleration characteristics of a typical high-pressure-ratio single-spool turbojet engine. Consideration of several operating lines on the compressor performance map with two turbine-inlet temperatures showed that for a minimum acceleration time the turbine-inlet temperature should be the maximum allowable, and the operating line on the compressor map should be as close to the surge region as possible throughout the speed range. Operation along such a line would require a continuously varying bleed area. A relatively simple two-step area bleed gives only a small increase in acceleration time over a corresponding variable-area bleed. For the modes of operation considered, over 84 percent of the total acceleration time was required to accelerate through the low-speed range ; therefore, better low-speed compressor performance (higher pressure ratios and efficiencies) would give a significant reduction in acceleration time.
Acceleration of high-pressure-ratio single-spool turbojet engine as determined from component performance characteristics III : effect of turbine stator adjustment
No Description Available.
An acceleration schedule control for accelerating a turbojet engine and its use with a speed control
No Description Available.
An acceleration schedule control for accelerating a turbojet engine and its use with a speed control
Accelerating-limiting controls for turbojet engines.
Accelerations in fighter-airplane crashes
From Introduction: "This report describes some measurements of these quantities obtained by crashing fighter aircraft under circumstances approximating those observed in service."
An active particle diffusion theory of flame quenching for laminar flames / Dorothy M. Simon and Frank E. Belles
An equation for quenching distance based on the destruction of chain carriers by the surface is derived. The equation expresses the quenching distance in terms of the diffusion coefficients and partial pressures of the chain carriers and gas phase molecules, the efficiency of the surface as a chain breaker, the total pressure of the mixture, and a constant which depends on the geometry of the quenching surface. Quenching distances measured by flashback for propane-air flames are shown to be consistent with the mechanism. The derived equation is used with the lean inflammability limit and a rate constant calculated from burning velocity data to estimate quenching distances for propane-air (hydrocarbon lean) flames satisfactorily.
Adaptation of a Cascade Impactor to Flight Measurement of Droplet Size in Clouds
A cascade impactor, an instrument for obtaining: the size distribution of droplets borne in a low-velocity air stream, was adapted for flight cloud droplet-size studies. The air containing the droplets was slowed down from flight speed by a diffuser to the inlet-air velocity of the impactor. The droplets that enter the impactor impinge on four slides coated with magnesium oxide. Each slide catches a different size range. The relation between the size of droplet impressions and the droplet size was evaluated so that the droplet-size distributions may be found from these slides. The magnesium oxide coating provides a permanent record. of the droplet impression that is not affected by droplet evaporation after the. droplets have impinged.
Adaptation of Combustion Principles to Aircraft Propulsion, Volume 2, Combustion in Air-Breathing Jet Engines
This volume continues the NACA study of combustion principles for aircraft propulsion. The various aspects of combustion pertinent to jet engines are organized and interpreted with quite extensive information, particularly for basic or fundamental. subject matter. The report concerns only air-breathing engines and hydrocarbon fuels, and not rocket engines and high-energy fuels. Since the references have been selected to illustrate important points, the bibliographies, while thorough, are not complete. This volumes describes the observed performance and design problems of engine combustors of the principal types. These include combustor-inlet conditions; starting, acceleration, combustion limits, combustion efficiency, coke deposits, and smoke formation in turbojets; ram-jet performance; and afterburner performance and design.
Adaptation of Combustion Principles to Aircraft Propulsion, Volume I, Basic Considerations in the Combustion of Hydrocarbon Fuels with Air
The report summarizes source material on combustion for flight-propulsion engineers. First, several chapters review fundamental processes such as fuel-air mixture preparation, gas flow and mixing, flammability and ignition, flame propagation in both homogenous and heterogenous media, flame stabilization, combustion oscillations, and smoke and carbon formation. The practical significance and the relation of these processes to theory are presented. A second series of chapters describes the observed performance and design problems of engine combustors of the principal types. An attempt is made to interpret performance in terms of the fundamental processes and theories previously reviewed. Third, the design of high-speed combustion systems is discussed. Combustor design principles that can be established from basic considerations and from experience with actual combustors are described. Finally, future requirements for aircraft engine combustion systems are examined.
Additional abstracts pertaining to seaplanes
From Summary: "About 500 additional references pertaining to hydrodynamic design of seaplanes have been compiled, and the information is presented in the form of abstracts classified under six main headings:GENERAL INFORMATION, HYDROSTATICS, HYDRODYNAMICS, AERODYNAMICS, OPERATION, and RESEARCH. The compilation is an extension of NACA RM No. L6I13, entitled "Abstracts Pertaining to Seaplanes," by Jerold M. Bidwell and Douglas A. King. An author index and a subject index are included."
Additional comparisons between computed and measured transonic drag-rise coefficients at zero lift for wing-body-tail configurations
From Introduction: "This report makes further comparisons of the theoretical computing method with available experimental results, showing effects of wing plan-form changes, and the effect of an airfoil-section change on a wing of given plan form."
Additional experimental heat-transfer and durability data on several forced-convection, air-cooled, strut-supported turbine blades of improved design
No Description Available.
Additional experiments with flat-top wing- body combinations at high supersonic speeds
Flat top wing body configuration effects on aerodynamic characteristics of supersonic aircraft.
Additional fatigue tests on effects of design details in 355-T6 sand-cast aluminum alloy
From Introduction: "Reported herein are results of the additional direct-stress fatigue tests on: (1) a plate-type specimen with cored centrally located hole and (2) 0.300-inch-diameter round polished specimens with various degrees of porosity."
Additional free-flight tests of the rolling effectiveness of several wing-spoiler arrangements at high subsonic, transonic, and supersonic speeds
From Introduction: "The purpose of the present paper is to present results obtained recently relating to the characteristics of a full-span sharp-edge spoiler with an 0.02-chord projection above the wing surface at several chordwise positions and also to the relative effectiveness of the sharp-edge spoiler and a wedge-type spoiler located at the 80-percent-chord line."
Additional measurements of the low-speed static stability of a configuration employing three triangular wing panels and a body of equal length
From Introduction: "The results of an investigation of the low-speed static stability of a simplified model of such an arrangement having one of the airfoils placed vertically on top of the body and the other two as wing panels having negative dihedral are presented in reference 1. In order to provide information for predicting the effects of changes in the basic configuration on the low-speed stability characteristics presented in reference 1, additional measurements have been made."
Additional results in a free-flight investigation of control effectiveness of full-span, 0.2-chord plain ailerons at high subsonic, transonic, and supersonic speeds to determine some effects of wing sweepback, aspect ratio, taper, and section thickne
No Description Available.
Additional results of an investigation at transonic speeds to determine the effects of a heated propulsive jet on the drag characteristics of a series of related afterbodies
From Introduction: "Presented in this report are the basic data obtained from investigation. The data are presented with limited analysis in order to expedite their availability to those concerned with jet-exit-afterbody design."
Additional Results on the Static Longitudinal and Lateral Stability Characteristics of a 0.05-Scale Model of the Convair F2Y-1 Airplane at High Subsonic Speeds
Additional results on the static longitudinal and lateral stability characteristics of a 0.05-scale model of the Convair F2Y-1 water-based fighter airplane were obtained in the Langley high-speed 7- by 10-foot tunnel over a Mach number range of 0.50 to 0.92. The maximum angle-of-attack range (obtained at the lower Mach numbers) was from -2 degrees to 25 degrees. The sideslip-angle range investigated was from -4 degrees to 12 degrees. The investigation included effects of various arrangements of wing fences, leading-edge chord-extensions, and leading-edge notches. Various fuselage fences, spoilers, and a dive brake also were investigated. From overall considerations of lift, drag, and pitching moments, it appears that there were two modifications somewhat superior to any of the others investigated: One was a configuration that employed a full-chord fence and a partial-chord fence located at 0.63 semispan and 0.55 semispan, respectively. The second was a leading-edge chord-extension that extended from 0.68 semispan to 0.85 semispan in combination with a leading-edge notch located at 0.68 semispan. With plus or minus 10 degrees aileron, the estimated wing-tip helix angle was reduced from 0.125 at a Mach number of 0.50 to 0.088 at a Mach number of 0.92, with corresponding rates of roll of 4.0 and 5.2 radians per second. The upper aft fuselage dive brake, when deflected 30 degrees and 60 degrees, reduced the rudder effectiveness about 10 to 20 percent and about 35 to 50 percent, respectively.
Additional Studies of the Stability and Controllability of an Unswept-Wing Vertically Rising Airplane Model in Hovering Flight Including Studies of Various Tethered Landing Techniques
No Description Available.
The adhesion of molten boron oxide to various materials
From Introduction: "The present report evaluates the amount of adhesion existing between the liquid boron oxide and various materials used in engines."
Adhesive and protective characteristics of ceramic coating A-417 and its effect on engine life of forged Refractaloy-26 (AMS 5760) and cast stellite 21 (AMS 5385) turbine blades
The adhesive and protective characteristics of National Bureau of Standards Coating A-417 were investigated, as well as the effect of the coating on the life of forged Refractaloy 26 and cast Stellite 21 turbine blades. Coated and uncoated blades were run in a full-scale J33-9 engine and were subjected to simulated service operations consisting of consecutive 20-minute cycles (15 min at rated speed and approximately 5 min at idle). The ceramic coating adhered well to Refractaloy 26 and Stellite 21 turbine blades operated at 1500 degrees F. The coating also prevented corrosion of the Refractaloy 26, a corrosion-sensitive nickel-base alloy, and of the Stellite 21, a relatively corrosion-resistant cobalt-base alloy. Although the coating prevented corrosion of both alloys, it had no apparent effect on blade life.
Aerodynamic and hydrodynamic characteristics of a deck-inlet multijet water-based-aircraft configuration designed for supersonic flight
From Introduction: "In the present investigation, lift, drag, and pitching moment were determined over a Mach number range 0.6 to 1.42. Smooth-water takeoff and landing stability and resistance were investigated. A brief check of the rough-water spray and behavior was also made."
Aerodynamic and hydrodynamic characteristics of a proposed supersonic multijet water-based hydro-ski aircraft with a variable-incidence wing
From Introduction: "The configuration described in this paper represents one approach to such an airplane and the results of the wind-tunnel and tank evaluations are presented. In the present investigation, the aerodynamic longitudinal characteristics over a Mach number range from 0.6 to 1.97 were obtained."
Aerodynamic and hydrodynamic characteristics of models of some aircraft-towed mine-sweeping devices : TED No. NACA AR 8201
From Introduction: "A study is being conducted by the U.S. Naval Air Development Center to determine the feasibility of several airborne magnetic mine-sweeping methods. The advantages of a satisfactory airborne method are greater safety and speed than are possible with existing surface methods. The three configurations investigated are described in some detail in reference 1 where they are designated as the double Q-sweep, the modified double-catenary sweep and the M-sweep."
Aerodynamic and inlet-flow-field characteristics at a free-stream Mach number of 3.0 for airplanes with circular fuselage cross sections and for two engine locations
No Description Available.
Aerodynamic and lateral-control characteristics of a 1/28-scale model of the Bell X-1 airplane wing-fuselage combination : transonic-bump method
No Description Available.
Aerodynamic characteristics and pressure distributions of a 6-percent-thick 49 degree sweptback wing with blowing over half-span and full-span flaps
From Introduction: "The investigation reported herein was initiated to define further the effects on the aerodynamic characteristics and load distribution of a thin, sweptback wing of a low-pressure blowing system and also to provide information on which to base a more thorough study of a complete airplane configuration."
Aerodynamic characteristics at a Mach number of 1.25 of a 6-percent-thick triangular wing and 6- and 9-percent-thick triangular wings in combination with a fuselage : wing aspect ratio 2.31, biconvex airfoil sections
No Description Available.
Aerodynamic characteristics at a Mach number of 1.38 of four wings of aspect ratio 4 having quarter-chord sweep angles of 0 degrees, 35 degrees, 45 degrees, and 60 degrees
No Description Available.
Aerodynamic Characteristics at a Mach Number of 6.8 of Two Hypersonic Missile Configurations, One with Low-Aspect-Ratio Cruciform Fins and Trailing-Edge Flaps and One with a Flared Afterbody and All-Movable Controls
No Description Available.
Aerodynamic characteristics at a Mach number of 6.8 of two hypersonic missile configurations, one with low-aspect-ratio cruciform fins and trailing-edge flaps and one with a flared afterbody and all-movable controls
No Description Available.
Aerodynamic characteristics at high and low subsonic Mach numbers of four NACA 6-series airfoil sections at angles of attack from -2 to 31 degrees
From Introduction: "The airfoil sections tested, which differ only in thickness ratio, were the NACA 64-006, 64-008, 64-010, and 641-012. Lift, drag, and pitching-moment data were obtained for Mach numbers of 0.3 to that for tunnel choke at angles of attack of -2^o to 31^o. The results of this investigation are reported herein."
Aerodynamic Characteristics at High and Low Subsonic Mach Numbers of the NACA 0012, 64(sub 2)-015, and 64(sub 3)-018 Airfoil Sections at Angles of Attack from -2 Degrees to 30 Degrees
An investigation has been made in the Langley low-turbulence pressure tunnel of the aerodynamic characteristics of the NACA 0012, 64(sub 2)-015, and 64(sub 3)-018 airfoil sections. Data were obtained at Mach numbers from 0.3 to that for tunnel choke, at angles of attack from -2deg to 30deg, and with the surface. of each airfoil smooth-and with roughness applied at the leading edge.The Reynolds numbers of the tests ranged from 0.8 x 10(exp 6) to 4.4 x 10(exp 6). The results are presented as variations of lift, drag, and quarter-chord pitching-moment coefficients with Mach number.
Aerodynamic characteristics at high speeds of a two-blade NACA 10-(3)(062)-045 propeller and of a two-blade NACA 10-(3)(08)-045 propeller
From Introduction: "The aerodynamic characteristics of a series of 10-foot-diameter propellers are being investigated in the Langley 16-foot high-speed tunnel in a comprehensive propeller research program. Using high-critical-speed NACA 16-series airfoil sections (reference 1), these propellers are designed to have Betz minimum induced-energy loss loading (reference 2) for a blade angle of 45^o at the 0.7 radius, when used as a four-blade propeller operating at an advance ratio of approximately 2.1 The ultimate purpose of the program is to determine the influence upon propeller design factors and of compressiblity; the propeller tests reported herein form part of the investigation of the effects of blade-section thickness ratio."
Aerodynamic characteristics at high speeds of full-scale propellers having Clark Y blade sections
From Introduction: "The single purpose of this paper is to make available the data obtained from tests of these two Clark Y section propellers as quickly as possible with no attempt being made to analyze the results or to compare them with other high-speed-propeller test results."
Aerodynamic Characteristics at High Speeds of Full-Scale Propellers having Different Shank Designs
Tests of two 10-foot-diameter two-blade propellers which differed only in shank design have been made in the Langley 16-foot high-speed tunnel. The propellers are designated by their blade design numbers, NACA 10-(5)(08)-03, which had aerodynamically efficient airfoil shank sections, and NACA l0-(5)(08)-03R which had thick cylindrical shank sections typical of conventiona1 blades, The propellers mere tested on a 2000-horsepower dynamometer through a range of blade-angles from 20deg to 55deg at various rotational speeds and at airspeeds up to 496 miles per hour. The resultant tip speeds obtained simulate actual flight conditions, and the variation of air-stream Mach number with advance ratio is within the range of full-scale constant-speed propeller operation. Both propellers were very efficient, the maximum envelope efficiency being approximately 0,95 for the NACA 10-(5)(08)-03 propeller and about 5 percent less for the NACA 10-(5)(08)-03R propeller. Based on constant power and rotational speed, the efficiency of the NACA 10-(05)(08)-03 propeller was from 2.8 to 12 percent higher than that of the NACA 10-(5)(08)-03R propeller over a range of airspeeds from 225 to 450 miles per hour. The loss in maximum efficiency at the design blade angle for the NACA 10-(5)(08)-03 and 10-(5)(08)-03R propellers vas about 22 and 25 percent, respectively, for an increase in helical tip Mach number from 0.70 to 1.14.
Aerodynamic characteristics at Mach number 4.04 of a rectangular wing of aspect ratio 1.33 having a 6-percent-thick circular-arc profile and a 30-percent-chord full-span trailing-edge flap
From Introduction: "The present report gives results at a Mach number of 4.04 of the part of the program concerned with flap controls at Mach numbers from 1.62 to 6.9."
Aerodynamic characteristics at Mach number of 2.01 of two cruciform missile configurations having 70 degree delta wings with length-diameter ratios of 14.8 and 17.7 with several canard controls
From Introduction: "The present paper contains the results of the investigation of the aerodynamic characteristics at Mach number of 2.01 of the two cruciform wing missiles equipped with larger canard controls and compares the result with that obtained previously with a smaller control."
Aerodynamic characteristics at Mach number of 4.06 of a typical supersonic airplane model using body and vertical-tail wedges to improve directional stability
No Description Available.
Aerodynamic characteristics at Mach numbers 2.36 and 2.87 of an airplane configuration having a cambered arrow wing with a 75 degree swept leading edge
From Introduction: "The results obtained in the wind-tunnel tests at Mach numbers 2.36 and 2.87 for several configurations utilizing this wing, including results on the wing alone are presented."
Aerodynamic characteristics at Mach numbers from 0.7 to 1.75 of a four-engine swept-wing airplane configuration as obtained from a rocket-propelled model test
No Description Available.