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- Acoustical Treatment for the NACA 8- by 6-Foot Supersonic Propulsion Wind Tunnel
- "This report presents results of a research and engineering program performed during the first half of 1950 that resulted in an acoustical treatment for the 8- by 6-foot supersonic wind tunnel at the Lewis Flight Propulsion Laboratory" (p. 1).
- 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 a Refined Deep-Step Planing-Tail Flying-Boat Hull with Various Forebody and Afterbody Shapes
- From Introduction: "The results of one phase of this investigation, presented in reference 1, have indicated that hull drag can be reduced without causing large changes in aerodynamic stability and hydrodynamic performance by the use of high length-beam ratios. Another phase of the investigation, reference 2, indicated that hulls of the deep-step planning-tail type have much lower air drag than the conventional type of hull and about the same aerodynamic stability; tank tests, reference 3, have indicated that this type of hull also has hydrodynamic performance equal to and in some respects superior to the conventional type of hull. Unpublished tank tests have indicated that the hull models presented in the present paper (with the possible exception of the forebody alone for which data are not available) will have acceptable hydrodynamic performance."
- 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 Design of High Mach Number Nozzles Utilizing Axisymmetric Flow with Application to a Nozzle of Square Test Section
- From Introduction: "A method for the design of three-dimensional nozzles based on axi-symmetric flow is presented in this paper. The design method presented in this paper is general; however, as an illustrative example of the design of a Mach number 10 nozzle with square test section is included."
- 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.
- Aerodynamic investigation of a four-blade propeller operating through an angle-of-attack range from 0 to 180 degrees
- Report presenting an investigation of the aerodynamic characteristics of a four-blade rigid model propeller in the full-scale tunnel for a range of angles of attack, blade angles, and advance ratio. It included a preliminary explanation of vertical descent and a comparison with theory. Results regarding the static thrust and forward flight are provided.
- Aerodynamic loads on a leading-edge flap and a leading-edge slat on the NACA 64A010 airfoil section
- From Summary: "The present report presents the chordwise distributions of pressure measured concurrently with the force and moment data of NACA TN 3007."
- 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).
- Air forces and moments on triangular and related wings with subsonic leading edges oscillating in supersonic potential flow
- From Introduction: "This report is concerned with the derivation of expressions for the velocity potential and associated forces and moments for oscillating triangular wings in supersonic flow. The purpose of the present report is to make use of the expanded form of the velocity potential to obtain the forces and moments, based on the first terms of this potential, for a rigid triangular wing performing vertical and pitching sinusoidal oscillations in mixed supersonic flow."
- 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 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."
- Analogue-computer simulation of an autopilot servo system having nonlinear response characteristics
- From Introduction: "The servo system considered in this report is in the latter category, due mainly to the fact its amplifier tends to saturate. An investigation of the longitudinal dynamic response of the stabilized airplane was made and the results were reported in reference 1. In this investigation it was found that when restricted to linear methods of analysis the performance of the autopilot-aircraft combination could be predicted for only the small range of operation where the elements of the autopilot operated within their linear range."
- 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 Supersonic Flow in the Region of the Leading Edge of Curved Airfoils, Including Charts for Determining Surface-Pressure Gradient and Shock-Wave Curvature
- Note presenting an investigation of the inviscid flow in the region of the leading edge of curved airfoils with attached shock waves. Tables and charts are presented for determining the surface-pressure gradient and the shock-wave curvature in supersonic flow of an ideal diatomic gas. An approximate procedure for determining the flow field a short distance downstream of the leading edge is also presented.
- 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 thrust augmentation of turbojet engines by water injection at compressor inlet including charts for calculating compression processes with water injection
- From Summary: "Curves are presented that show the theoretical performance of the augmentation method for various amounts of water injected and the effects of varying flight Mach number, altitude, ambient-air temperature, ambient relative humidity, compressor pressure ratio, and inlet-diffuser efficiency. Numerical examples, illustrating the use of the psychrometric chart and the Mollier diagram in calculating both compressor-inlet and compressor-outlet conditions when water is injected at the compressor inlet, are presented."
- 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 Derivation and Experimental Evaluation of Short-Bearing Approximation for Full Journal Bearing
- From Introduction: "This report extends the short-bearing pressure-distribution function of Michell and Cardullo to give equations for the various bearing characteristics. This short-bearing approximation makes available formulas relating eccentricity ratio to applied load, attitude angle, angular position of peak film pressure to unit pressure on projected area."
- 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."
- An analytical investigation of airplane spin-recovery motion by use of rotary-balance aerodynamic data
- From Introduction: "Many investigations have been made in the Langley 20-foot free-spinning tunnel in which the natures of airplane spins and recoveries have been determined experimentally with dynamically scaled-down models. The results of some of these investigations are presented in references 1 to 5."
- 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 Method for Determining Transmission and Absorption of Time-Dependent Radiation Through Thick Absorbers 3: Absorber With Radioactive Daughter Products
- Report presenting a theoretical treatment of absorption problems that considers the following cases: radiation is normal to an absorber with plane parallel surfaces, radiations are of several polyenergetic types, induced radioactive isotopes decay to stable atoms in multistep decay processes, and radiations from the absorber affect the time-dependency of the source activity. Radiation from intermediate isotopes can become more dangerous than the original activity, so the entire range of radiations must be accounted for.
- 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."
- Applicability of the hypersonic similarity rule to pressure distributions which include the effects of rotation for bodies of revolution at zero angle of attack
- The analysis of Technical Note 2250, 1950, is extended to include the effects of flow rotation. It is found that the theoretical pressure distributions over drive cylinders can be related by the hypersonic similarity rule with sufficient accuracy for most engineering purposes. The error introduced into pressure distributions and drag effective cylinders by ignoring the rotation term in the characteristic equations is investigated.