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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 of a 6-Percent-Thick Symmetrical Circular-Arc Airfoil Having a 30-Percent-Chord Trailing-Edge Flap at a Mach Number of 6.9
Memorandum presenting an investigation of the flow characteristics over a 6-percent-thick symmetrical circular-arc airfoil section with a 30-percent-chord trailing-edge flap at a Mach number of 6.90 and a Reynolds number of 1.65 x 10(sub 6). The model was tested over an angle-of-attack range of 0 to 16 degrees and a flap-deflection range of -16 degrees to 16 degrees. Results regarding pressure results and aerodynamic characteristics are provided.
Aerodynamic Characteristics of a 45 Degree Swept Wing Fighter Airplane Model and Aerodynamic Loads on Adjacent Stores and Missiles at Mach Numbers of 1.57, 1.87, 2.16, and 2.53
Report discussing tests to determine the aerodynamic characteristics of a model of a 45 degree swept-wing fighter airplane and to determine the loads on attached stores and detached missiles. An investigation into aileron-spoiler effectiveness, aileron hinge moments, and the effects of wing modifications of aerodynamic characteristics was also carried out at various Mach numbers. Results are presented, but caution is provided in regards to extrapolating results from the model onto a full-scale aircraft.
Aerodynamic Characteristics of a 45 Degree Swept-Wing Fighter-Airplane Model and Aerodynamic Loads on Adjacent Stores and Missiles at Mach Numbers of 1.57, 1.87, 2.16, and 2.53
Memorandum presenting an investigation in the Unitary Plan wind tunnel to determine the aerodynamic characteristics of a model of a 45 degree swept-wing fighter airplane, and to determine the loads on attached stores and detached missiles in the presence of the model. Results also included a determination of aileron-spoiler effectiveness, aileron hinge moments, and the effects of wing modifications on model aerodynamic characteristics. The results are presented with minimum analysis.
Aerodynamic Characteristics of Four Wings of Sweepback Angles 0 Degrees, 35 Degrees, 45 Degrees, and 60 Degrees, NACA 65A006 Airfoil Section, Aspect Ratio 4, and Taper Ratio 0.6 in Combination With a Fuselage at High Subsonic Mach Numbers and at a Mach Number of 1.2
Report discussing an investigation of the effect of sweepback angle on wing-fuselage characteristics at a subsonic and a supersonic Mach number. Lift, drag, and pitching-moment coefficients, downwash-angle, and total-pressure measurements are all provided.
Aerodynamic Characteristics of Missile Configurations With Wings of Low Aspect Ratio for Various Combinations of Forebodies, Afterbodies, and Nose Shapes for Combined Angles of Attack and Sideslip at a Mach Number of 2.01
"An investigation has been made in the Langley 4-by-4-foot supersonic pressure tunnel to determine the aerodynamic characteristics of a series of missile configurations having low-aspect-ratio wings at a Mach number of 2.01. The effects of wing plan form and size, length-diameter ratio, forebody and afterbody length, boattailed and flared afterbodies, and component force and moment data are presented for combined angles of attack and sideslip to about 28 degrees. No analysis of the data was made in this report" (p. 1).
Aerodynamic characteristics of several flap-type trailing-edge controls on a trapezoidal wing at Mach numbers of 1.61 and 2.01
Report presenting an investigation at Mach numbers of 1.61 and 2.01 to determine the control effectiveness and hinge-moment characteristics for a series of 25.4-percent-chord trailing-edge controls on a trapezoidal wing with a 23 degree sweptback leading edge, aspect ratio of 3.1, and taper ratio of 0.4. Pressure distribution and hinge-moment measurements were made at a range of angles of attack and control deflections. Results regarding effect of control deflection, effect of wing angle of attack, effect of Reynolds number, effect of trailing-edge thickness, effect of hinge-line gap, effect of Mach number, and effect of control size and location are provided.
Aerodynamic characteristics of several jet-spoiler controls on a 45 degree sweptback wing at Mach numbers of 1.61 and 2.01
Report presenting an investigation in the supersonic pressure tunnel at two Mach numbers to determine the aerodynamic characteristics of several jet-spoiler controls on a wing having a 45 degree sweepback of the quarter-chord line, an aspect ratio of 3.5, a taper ratio of 0.3, and an NACA 65A005 airfoil section. Testing indicated that the jet-spoiler effectiveness increased with increasing angle of attack and correlated well with the momentum of jet flow.
Aerodynamic Characteristics of Tapered Wings Having Aspect Ratios of 4, 6, and 8, Quarter-Chord Lines Swept Back 45 Degrees, and NACA 63(Sub 1)a012 Airfoil Sections: Transonic-Bump Method
Report presenting testing of a series of three wings over a range of Mach numbers by the use of the transonic-bump technique. The lift, drag, pitching-moment, and root-bending-moment data of wings of a variety of aspect ratios but with the same quarter-chord lines and airfoil sections were obtained.
The aerodynamic characteristics throughout the subsonic speed range of a thin, sharp-edged horizontal tail of aspect ratio 4 equipped with a constant-chord elevator
From Introduction: "Recent investigations have indicated several wing plan forms, wing sections, and wing-body-tail combinations suitable for flight at supersonic speeds. One such lifting surface, a thin, sharp-edged without sweep of aspect ratio 4 and taper ratio 0.5, has been the subject of an investigation in the Ames 12-foot pressure wind tunnel. The aim of the investigation was to determine the aerodynamic characteristics of such a wing plan form throughout the range of subsonic Mach numbers up to 0.94."
Aerodynamic Heating and Boundary-Layer Transition on a 1/10-Power Nose Shape in Free Flight at Mach Numbers Up to 6.7 and Free-Stream Reynolds Numbers Up To 16 x 10(Exp 6)
Report presenting testing of a modified 1/10-power nose shape in free flight at Mach numbers up to 6.7. Measured heating rates were presented and compared with calculated values. Results regarding transition and comparison with previous investigations are provided.
Aerodynamics of Oscillating Control Surfaces at Transonic Speeds
Memorandum presenting a discussion of oscillating flap-type and all-movable controls with particular emphasis on the aerodynamic forces and moments at transonic speeds. Hinge-moment results from recent wind-tunnel and rocket-powered-model tests are summarized for trailing-edge flap-type controls to illustrate the effects of control hinge-line position and profile shape on one-degree-of-freedom flutter of this type of control.
Aileron and Elevator Hinge Moments of the Bell X-1 Airplane Measured in Transonic Flight
"During the flight investigation of the X-1 airplane the hinge moments of the elevator and aileron control surfaces have been measured over a Mach number range extending to above 1.0. The results of these measurements are presented in this paper" (p. 2).
Altitude Investigation of Can-Type Flame Holder in 20-Inch-Diameter Ram-Jet Combustor
From Introduction: "The combustor efficiency, combustor total-pressure ratio, combustor-outlet total pressure, combustor-inlet Mach number, and specific fuel consumption are presented. The effect of combustor length on efficiency and the effect of pilot operating conditions burning limits are also presented."
Altitude Investigation of Can-Type Flame Holder in 20-Inchdiameter Ram-Jet Combustor
Memorandum presenting an investigation of a can-type flame holder employing a fuel-air-mixture control sleeve in a 20-inch-diameter ramjet combustor conducted by free-jet and direct-connect techniques at a simulated flight Mach number of 3.0 and altitudes from about 70,000 to 80,000 feet. Results regarding the effect of shortening combustion chamber and effect of pilot-burner variables are provided.
Altitude Performance and Operational Characteristics of YJ71-A-7 Turbojet Engine
"Altitude performance of a YJ71-A-7 turbojet engine, with afterburner inoperative, was determined in the NACA Lewis altitude wind tunnel over a wide range of flight conditions. Engine speed and exhaust-nozzle area were controlled independently during this investigation. The variation of corrected values of air flow, net thrust, and fuel flow with corrected engine speed was not defined by a single curve with changes in altitude at given flight Mach number" (p. 1).
Altitude performance investigation of a high-temperature afterburner
From Introduction: "In response to the ever-increasing need for high thrust augmentation, an investigation was conducted that had as its primary objective the attainment of maximum exhaust-gas temperature and thrust (ref. 1). The investigation reported herein was therefore conducted to ascertain the operational limits of the most promising high-temperature afterburner design of reference 1 and to determine its performance over a wind range of flight conditions."
Altitude performance investigation of single- and double-annular turbojet-engine combustors with various size fuel nozzles
From Introduction: "The purpose of the investigation conducted at the NACA Lewis laboratory and reported herein was to determine the improvements possible in full-scale turbojet-engine performance when a single-annular combustor with slotted air-inlet orifices was used."
Altitude Performance of a 20-Inch-Diameter Ram-Jet Engine Investigated in a Free-Jet Facility at Mach Number 3.0
Report discussing the performance of a 20-inch-diameter ram-jet engine at Mach number 3.0 over a range of simulated altitudes from 60,500 to 66,500 feet. Information about the maximum combustor efficiency, range of exhaust-nozzle total pressures, lean blow-out, diffuser total-pressure recovery, and internal thrust coefficient is provided.
Altitude Performance of a 20-Inch-Diameter Ram-Jet Engine Investigated in a Free Jet Facility at Mach Number 3.0
Report presenting an investigation of the performance of a 20-inch-diameter ram-jet engine at Mach number 3.0 in a free-jet facility over a range of simulated altitudes. Results regarding the diffuser characteristics, combustor performance, thrust output, and operational characteristics are provided.
Altitude Performance of Modified J71 Afterburner with Revised Engine Operating Conditions
From Summary: "An investigation was conducted in an altitude test chamber at the NACA Lewis laboratory to determine the effect of a revision of the rated engine operating conditions and modifications to the afterburner fuel system, flameholder, and shell cooling on the augmented performance of the J71-A-2 (x-29) turbo jet engine operating at altitude . The afterburner modifications were made by the manufacturer to improve the endurance at sea-level, high-pressure conditions and to reduce the afterburner shell temperatures. The engine operating conditions of rated rotational speed and turbine-outlet gas temperature were increased. Data were obtained at conditions simulating flight at a Mach number of 0.9 and at altitudes from 40,000 to 60,000 feet."
Altitude Starting Tests of a Small Solid Propellant Rocket
From Summary: "Four solid-propellant rocket engines of nominal 500-pound thrust were tested for starting characteristics at pressure altitudes ranging from 89,000 to 111,000 feet and at a temperature of -75^o F. Chamber pressures were measured on two of the runs. Average chamber pressures in these two runs were lower than expected, although action times agreed with the expected values."
Altitude-Test-Chamber Investigation of McDonnell Afterburner on J34 Engine
"An altitude-test-chamber investigation was conducted to determine the operational and performance characteristics of a McDonnell afterburner with a fixed-area exhaust nozzle on a J34 engine. At rated engine speed, the altitude limit, as determined by combustion blow-out, occurred as a band of unstable operation of about 6000-foot altitude in width with minimum altitude limits from 31,000 feet at a simulated flight Mach number of 0.40 to about 45,500 feet at a simulated flight Mach number of 1.00. Considerable difficulty was experienced in attempting to establish or maintain balanced-cycle engine operation at altitudes above 36,000 feet" (p. 1).
Altitude Wind Tunnel Investigation of High-Temperature Afterburners
From Introduction: "During previous investigations of afterburning conducted at the NACA Lewis laboratory (references 1 to 4, for example), the objective of obtaining high exhaust-gas temperatures and, consequently, maximum thrust augmentation was compromised to some extent in order to alleviate the problem of afterburner shell cooling. The primary objective of the investigation reported herein was therefore the attainment of maximum exhaust-gas temperature imposed by the cooling techniques previously used, a secondary flow of cooling air was provided around the afterburner shell."
Altitude-wind-tunnel investigation of thrust augmentation of a turbojet engine IV: performance with tail-pipe burning and water injection
From Introduction: "Thrust augmentation of an axial-flow-type turbojet engine by burning fuel in the tail pipe is discussed in references 1 to 3. Thrust augmentation of the same turbojet engine by water injection at the compressor inlet is reported in reference 4."
Analyses for Turbojet Thrust Augmentation With Fuel-Rich Afterburning of Hydrogen, Diborane, and Hydrazine
Turbojet thrust augmentation with fuel-rich afterburning of hydrogen, diborane, and hydrazine was computed. Results regarding takeoff thrust augmentation and flight thrust augmentation are provided.
Analyses for turbojet thrust augmentation with fuel-rich afterburning of hydrogen, diborane, and hydrazine
From Introduction: "This report presents net thrusts computed for hydrogen, diborance, and hydrazine with fuel-air ratios form stoichiometric values to 0.5. Net thrusts for fuel-rich afterburning are compared with those for stoichiometric combustion of the turbojet fuel and air augmented with a 220-second specific-impulse rocket."
An analysis of axial- and centrifugal-flow turbojet-engine performance with variable-area exhaust nozzle
From Introduction: "The purpose of this report is to compare the effect on engine performance of the variable-area exhaust nozzle for axial- and centrifugal-flow turbojet engines."
Analysis of Factors Affecting Selection and Design of Air-Cooled Single-Stage Turbines for Turbojet Engines 2: Analytical Techniques
Memorandum presenting computation methods for analyzing turbojet-engine performance for a series of air-cooled nonafterburning and afterburning engines where all the engine components are simultaneously aerodynamically limited. The coolant-flow ratio was arbitrarily assigned so that the results of the analysis can be applied to any specific air-cooled blade configurations.
Analysis of Stage Matching and Off-Design Performance of Multistage Axial-Flow Compressors
From Introduction: "The present report is intended to give a qualitative picture of the operation of each stage of a multistage compressor over a range of actual operating conditions from 50 to 100 percent design speed and to point out some means of achieving improved off-design performance. The method used in the report is primarily analytical and is based on single-stage-performance results."
An Analysis of the Effect of Structural Feedback on the Flutter of a Control Surface Having a Power-Boost System
From Summary: "Such devices as leading- and trailing-edge flaps which are now in use on operational aircraft permit the attainment of maximum airplane lift coefficients, power-off, of the order of 2.8 (reference 1). Airfoil-section maximum lift coefficients as high as 5.5 have been obtained in wind-tunnel tests (see, for example, reference 2), and in a limited flight investigation airplane lift coefficients of 4.2 were obtained (reference 3)."
Analysis of transonic rotor-blade passage loss with hot-wire anemometers
From Introduction: "This report presents data from measurements of the flow in a single-stage research compressor, which supports the model of reference 1. A calculated shock technique similar to that of reference 1 is incorporated with these experimental results. Another approach for estimating passage shock loss given a flow rate and blade geometry was reported in reference 2."
Analysis of two-spool turboprop-engine characteristics
From Introduction: "The purpose of this report is to present the results of an analytical investigation of the engine characteristics of two-spool engines with high over-all compressor pressure ratio (12.0 at design). Some of the turbine design problems encountered in a single-spool engine with current compressor pressure ratio (7.32 at design) were investigated in reference 1. The investigation was extended in reference 2 to cover the effect of mode of engine operation on the turbine design requirements and engine performance for a single-spool engine with current compressor pressure ratio."
Analytical and experimental investigation of a temperature-schedule acceleration control for a turbojet engine
From Introduction: "This report investigates some of the problems involved in scheduling the tailpipe temperature to avoid stall during acceleration. The object of this report is to investigate the dynamics of a closed-loop acceleration control that follows a schedule of tailpipe temperature with rotor speed."
Analytical evaluation of effect of inlet-air temperature and combustion pressure on combustion performance of boron slurries and blends of pentaborane in octene-1
From Summary: "The effects of variation in inlet-air temperature, combustion pressure, and boron or pentaborane concentration on combustion performance were discussed. It was shown how the theoretical data herein could be employed in obtaining the combustion efficiency of experimental combustors. Data were presented by which combustion efficiencies obtained with a water-quench heat balance could be adjusted for the heat of dissociation of the combustion products."
Analytical Investigation of Fuel-Cooled Turbine Blades With Return-Flow Type of Finned Coolant Passages
Memorandum presenting an investigation of coolant-flow rates for a turbine rotor blade with return-flow type of coolant-passage configuration formed by fins within a capped blade shell with both hydrogen and methane fuels as coolants. Results regarding spanwise blade and coolant temperature distributions, effects of coolant inlet temperature on hydrogen-coolant-flow requirements, comparison of return-flow-blade coolant requirements, effect of fin thickness and fin height, comparison of hydrogen and methane as coolants, and feasibility of fuel-cooled turbines are provided.
Analytical investigation of fuel-cooled turbine blades with return-flow type of finned coolant passages
From Introduction: "The purpose of this report was to investigate the possible use of engine fuels (hydrogen and methane) as coolants for turbine rotor blades and to determine the pressure-drop characteristics of these coolants for a turbine blade with a more effective coolant-passage configuration than that considered in reference 5 but for the same engine and flight conditions."
Analytical study of blockage- and lift-interference corrections for slotted tunnels obtained by the substitution of an equivalent homogeneous boundary for the discrete slots
From Introduction: "This paper will treat the problem in the suggested manner, beginning with the development of a suitable boundary condition to represent mathematically a homogeneous boundary which has the same flow characteristics, at a point in the flow sufficiently removed from the boundary as the actual physical boundary of alternate open and closed portions of the wall. Numerical results will be presented for circular tunnels with uniformly distributed around the circumference, for rectangular tunnels with uniformly distributed around the circumference, for rectangular tunnels with uniformly distributed slots in the top and bottom walls, for rectangular tunnels with the slot distribution determined by a transformation from a uniformly slotted circular tunnel, and for a two-dimensional tunnel. The results of this paper are derived on the basis of an incompressible potential flow."
An Analytical Study of the Comparative Performance of Four Air-Induction Systems for Turbojet-Powered Airplanes Designed to Operate at Mach Numbers Up to 1.5
Memorandum presenting a study made to ascertain some of the operational characteristics of four types of air-induction systems for a turbojet-powered airplane intended to operate at a range of Mach numbers at an altitude of 35,332 feet. The investigation included air-induction systems with and wthout ramps to produce oblique shock waves, with fixed and variable inlet areas, and with divergent diffusers.
Analytical Study of the Comparative Pitch-Up Behavior of Several Airplanes and Correlation With Pilot Opinion
From Introduction: "An extension of the work presented in reference 2, the method was applied to six swept-wing airplanes for which the pilot opinion was well documented. The analytical results obtained are used herein to illustrate how wind-tunnel data may be used to predict the pitching motions and the comparative pitch-up behavior of new airplane designs or to assess the effects of modifications on existing airplanes."
An Anaylsis of Control Requirements and Control Parameters for Direct-Coupled Turbojet Engines
"Requirements of an automatic engine control, as affected by engine characteristics, have been analyzed for a direct-coupled turbojet engine. Control parameters for various conditions of engine operation are discussed. A hypothetical engine control is presented to illustrate the use of these parameters. An adjustable speed governor was found to offer a desirable method of over-all engine control. The selection of a minimum value of fuel flow was found to offer a means of preventing unstable burner operation during steady-state operation" (p. 1).
Attenuation of Tangential-Pressure Oscillations in a Liquid-Oxygen-n-Heptane Rocket Engine With Longitudinal Fins
Attenuation of tangent-pressure oscillation in liquid-oxygen-heptane rocket engine combustion chamber using longitudinal fin. Results regarding the engine performance with injector A, effect of fins with injector A, and destructiveness of screaming are provided.
Attenuation of tangential-pressure oscillations in a liquid-oxygen - n-heptane rocket engine with longitudinal fins
An investigation of the use of fins to prevent high-frequency combustion-pressure oscillations (screaming) in the combustion chamber of a 1000-pound-thrust rocket engine with a chamber pressure of 300 pounds per square inch and using liquid oxygen and n-heptane as propellants. Tangential combustion-pressure oscillations were found to be eliminated with longitudinal fins located in the combustion zone. Results regarding engine performance, effect of fins, and destructiveness of screaming are provided.
A Bibliography of NACA Reports on Control of Turbojet Engines
Memorandum presenting an annotated bibliography of NACA reports containing information of interest to designers and manufacturers of controls for turbojet engines. The eleven major topics include starting, acceleration, flame-out, temperature control, stability and dynamics of small disturbances, combustion dynamics, engine inlet diffuser control, steady-state engine performance, fuel systems, sensors, and general control system theory.
Boundary-Layer Measurements on Several Porous Materials With Suction Applied
Memorandum presenting the boundary-layer velocity profiles were measured on ten samples of various porous materials and on impervious aluminum plate mounted flush with the inner surface of the side wall of a small wind tunnel. Suction was applied to the back side of the porous test materials through a 4-inch-square opening. Results regarding measurements on the impervious plate and measurements on porous materials without suction and with suction are provided.
A Brief Hydrodynamic Investigation of a 1/24-Scale Model of the DR-77 Seaplane
From Summary: "A limited investigation of a 1/24-scale dynamically similar model of the Navy Bureau of Aeronautics DR-77 design was conducted in Langley tank no. 2 to determine the calm-water take-off and the rough-water landing characteristics of the design with particular regard to the take-off resistance and the landing accelerations. During the take-off tests, resistance, trim, and rise were measured and photographs were taken to study spray. During the landing tests, motion-picture records and normal-acceleration records were obtained."
Calculation of Aerodynamic Forces on an Inclined Dual-Rotating Propeller
Report presenting a method for calculating the aerodynamic forces on the blades of a dual-rotating propeller with its thrust axis inclined to the air stream. Comparison of the fluctuating aerodynamic forces due to pitched or yawed operation of a dual-rotating propeller show that the fluctuation in forces on the front component tend to be greater than those on the rear component.
Calculation of the Lateral Stability of a Directly Coupled Tandem-Towed Fighter Airplane and Correlation with Experimental Data
"A theoretical method is presented for predicting the dynamic lateral stability characteristics of an airplane towed in tandem by a much larger airplane. Values of period and time to damp to one-half amplitude and rolling motions calculated by an analog computer have been correlated with results of two experimental investigations conducted in the Langley free-flight tunnel which were part of a U.S. Air Force program (Project FICON) to develop a satisfactory arrangement by which a bomber could tow a parasite fighter. In general, the theoretical results agree with the experimental results" (p. 1).
Canard Hinge Moments and Longitudinal Stability of a 1/7-Scale Model of the Convair B-58 External Store in a Free-Flight Investigation at Mach Numbers From 0.94 to 2.58
Report presenting a longitudinal stability and control investigation of a model of the Convair B-58 external store over a range of Mach numbers. Normal force, chord force, and static and dynamic stability derivatives are provided. Abrupt pitching disturbances were created by step-function movements of the canard surface.
Canard Hinge Moments and Longitudinal Stability of a 1/7-Scale Model of the Convair B-58 External Store in a Free-Flight Investigation at Mach Numbers From 0.94 to 2.58: Coord. No. AF-204
Memorandum presenting a longitudinal stability and control investigation made over a range of Mach numbers of a scale model of the Convair B-58 external store. Normal force, chord force, and static and dynamic stability derivatives formed an important part of the results. Results regarding the hinge moments and longitudinal trim and force coefficients are also provided.
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