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- Performance and Component Frontal Areas of a Hypothetical Two-Spool Turbojet Engine for Three Modes of Operation
- Engine performance is better for constant outer-spool mechanical-speed operation than for constant inner-spool mechanical-speed operation over most of the flight range considered. Combustor and afterburner frontal areas are about the same for the two modes. Engine performance for a mode characterized by a constant outer-spool equivalent speed over part of the flight range and a constant outer-spool mechanical speed over the rest of the flight range is better that that for constant outer-spool mechanical speed operation.
- Aerodynamic principles for the design of jet-engine induction systems
- From Introduction: "It is the purpose of this report to assemble principles of induction-system design for flight to a Mach number of 2 and to use existing data to show the consequences of compromising them."
- Static Longitudinal and Lateral Stability and Control Characteristics of an Airplane Configuration Having a Wing of Trapezoidal Plan Form With Various Tail Airfoil Sections and Tail Arrangements at a Mach Number of 6.86
- Memorandum presenting an investigation carried out in the 11-inch hypersonic tunnel to determine the static longitudinal and lateral stability and control characteristics of an airplane configuration with a trapezoidal wing with a modified hexagonal airfoil section and equipped with various tail airfoil sections and tail arrangements. The tests were made at Mach number 6.86 and Reynolds number 343,000 based on the wing mean aerodynamic chord.
- Flight Determination of the Longitudinal Stability and Control Characteristics of the Bell X-5 Research Airplane at 58.7 Degrees Sweepback
- Memorandum presenting the Bell X-5 research airplane tested at 58.7 degrees sweepback during the program to determine the characteristics of a variable-sweep fighter airplane at transonic speeds. This paper includes the stability and control characteristics in the stable lift range up to Mach numbers near 1.0 at an altitude of 40,000 feet and to slightly lower Mach numbers at altitudes of 25,000 feet and 15,000 feet. Results regarding general comments, static stability and control characteristics, and longitudinal dynamic stability are provided.
- A method for evaluating the loads and controllability aspects of the pitch-up problem
- Report presenting a procedure for estimating the range of peak airplane load factors and maneuvering tail loads likely to be experienced in pitch-up maneuvers. Results of computations indicated that though the load factors and maneuvering tail loads were not critical in pitch-up maneuvers at 35,000 feet, they were likely to exceed design levels at 15,200 feet.
- A Theoretical Investigation of a Compensating Network With Application to Roll Control Systems for Automatic Interceptors
- Memorandum presenting a theoretical analysis of an airplane automatic control system incorporating a compensating network. The compensating network is a computing network that has characteristics that are the inverse of the airframe; consequently, airplane dynamics are eliminated from the system response. Results regarding the displacement control system, the velocity command system, and the acceleration control system are provided.
- An experimental investigation at a Mach number of 2.01 of the effects of body cross-section shape on the aerodynamic characteristics of bodies and wing-body combinations
- Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effect of changes in body cross-section shape on the aerodynamic characteristics of bodies and wing-body combinations. A series of 13 bodies of a given length and volume but various cross-section shapes were tested at a Mach number of 2.01. The results showed that changes in drag at zero lift due to changes in body cross-section shape from the basic circular shape are small and of the same order as the test accuracy.
- Effect of Wing Size and Amount of Indentation on Applicability of Transonic Area Rule to Swept-Wing Configurations
- Memorandum presenting a systematic transonic zero-lift drag investigation utilizing a swept-wing configuration with three different ratios of wing to fuselage size utilizing a 6-inch helium gun. The experiments and comparisons with other results indicated that the reduction of pressure drag obtainable from partial indentation is approximately proportional to the amount of indentation employed up to a Mach number of 1.3. Results regarding the basic data, total drag, pressure drag, equivalent bodies, and special projections are provided.
- Analysis of effects of airplane characteristics and autopilot parameters on a roll-command system with aileron rate and deflection limiting
- From Summary: "The dynamic characteristics of an airplane with a proportional-gain roll-control autopilot are discussed. A comparison of three different high-speed fighter airplanes is presented. The dynamic effects of time lags and various gains in the system are described."
- Experimental Drag Coefficients of Round Noses With Conical Windshields at Mach Number 2.72
- "An exploratory investigation at Mach number 2.72 has been made to show the decrease in the drag of a round-nose model achieved by mounting a small cone on a rod ahead of the nose. The geometric parameters which were varied were the cone-base diameter, cone angle, and rod length. All models showed large decreases in drag compared to that of the round nose alone" (p. 1).
- A Study of the Correlation Between Flight and Wind-Tunnel Buffeting Loads
- Report presenting a comparison of the buffet loads measured on wind-tunnel models with loads measured in flight, which indicate that a simple strain-gage measurement can be used in wind tunnel testing that can be used to predict the wing buffet loads on the airplane. The technique appears to be usable for both unswept and swept configurations.
- Static longitudinal and lateral stability and control characteristics of an 0.065-scale model of the Chance Vought Regulus II missile at Mach numbers of 1.41, 1.61, and 2.01: TED No. NACA AD 398
- Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the static longitudinal and lateral stability and control characteristics of an 0.065-scale model of the Chance Vought Regulus II missile. The tests were made at three Mach and Reynolds numbers.
- Load distributions on wings and wing-body combinations at high angles of attack and supersonic speeds
- Report presenting an investigation of aircraft which are required to maneuver rapidly at extreme altitudes, which involves reaching maximum loads at high angles of attack. Load information is necessary for that flight condition and for aircraft that reach their maximum loads at high speed and high dynamic pressures. Results regarding the wings and wing-body combinations are provided.
- Some Recent Experimental Data on Three-Dimensional Oscillating Air Forces
- Report presenting the status of oscillating air forces, including forces, moments, and their respective phase angles for a 45 degree swept wing of aspect ratio 2 and for two bodies of revolution. Derivatives based on available analyses were also demonstrated for those three configurations.
- Investigation of the effects of body indentation and of wing-plan-form modification on the longitudinal characteristics of a 60 degree swept-wing-body combination at Mach numbers of 1.41, 1.61, and 2.10
- Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects of body indentation on the minimum drag and maximum lift-drag ratio of a 60 degree swept-wing-body combination. A secondary goal of the tests was to determine the effect on the maximum lift-drag ratio of modifying the inboard plan form of the 60 degree swept wing. Lift, drag, and pitching-moment data are presented.
- Theoretical investigation of the effects of configuration changes on the center of pressure shift of a body-wing-tail combination due to angle of attack and Mach number at transonic and supersonic speeds
- Report presenting a theoretical investigation to study the effects of systematic changes in configuration of a representative airframe on the center-of-pressure travel due to changes in angle of attack and in Mach number. The airframe was an unbanked canard missile configuration with low-aspect-ratio coplanar wing and tail surfaces of triangular plan form. Results regarding the center-of-pressure shift due to angle of attack, center-of-pressure shift due to Mach number, and combined effects of angle of attack and Mach number are provided.
- Effects of leading-edge radius on the longitudinal stability of two 45 degree sweptback wings as influenced by Reynolds numbers up to 8.20 x 10(exp 6) and Mach numbers up to 0.303
- Report presenting an investigation to show the effects of systematic changes of leading-edge radius, aspect ratio, Reynolds number, and Mach number on the static longitudinal aerodynamic characteristics of sweptback wings in the 19-foot pressure tunnel. Results regarding the effects of leading-edge radius and aspect ratio and effect of Reynolds number and Mach number are provided.
- A study of service-imposed maneuvers of four jet fighter airplanes in relation to their handling qualities and calculated dynamic characteristics
- Report presenting results from a flight program conducted to obtain information on the airplane response and actual rates and amounts of control motion used by service pilots to perform squadron operational training missions, which are correlated with the airplane handling qualities and calculated maximum dynamic response. Results regarding longitudinal characteristics, rolling characteristics, and sideslip characteristics are provided.
- Performance characteristics of hemispherical target-type thrust reversers
- Report presenting an investigation to determine the reverse-thrust performance of hemispherical target-type thrust reversers over a wide range of geometric variables. Several factors were found that increased the flow turn angle and reverse-thrust ratio, primarily the hemisphere diameter. Results regarding operating characteristics, relation of flow turn angle and reverse-thrust ratio, reverse-flow velocities and pressures along boattail, effect of boattail shape on reverse-thrust ratio, and modifications to hemispherical thrust reverser are provided.
- 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."
- High-Altitude Performance of an Experimental Turbular Prevaporizing Combustor
- Memorandum presenting an investigation of an experimental tubular combustor that provides for prevaporizing and premixing of the fuel with a part of the air before its introduction into the combustion zone. Combustion efficiency and total-pressure loss data are presented for three configurations selected from a total of 43 different modifications investigated. Results regarding the combustor development, comparison of liquid and gaseous fuel, combustor total-pressure losses, combustor-outlet temperature distribution, and evaluation of experimental prevaporizing combustors are provided.
- Preliminary investigation at Mach number 1.9 of simulated wing-root inlets
- Report presenting an experimental investigation to study several wing-root inlet configurations at Mach number 1.9. The inlets were of triangular and rectangular shape and external compression was provided by two-dimensional wedge surfaces. Results regarding the pressure-recovery and mass-flow data, effect of inlet side plates and curved diffusers, exit and inlet total-pressure distributions, improvement of exit total-pressure profiles, and inlet tests at zero flight speed are provided.
- An investigation of string support interference on base pressure and forebody chord force at Mach numbers from 0.60 to 1.30
- Report presenting testing to determine the interference effects of various sting-support configurations on the base pressure and foredrag characteristics of a wing-fuselage combination with a turbulent boundary layer. The primary variable investigated was the length of the constant-diameter portion of a sting support. Results regarding the base-pressure interference and foredrag interference are provided.
- Investigation to Mach number 2.0 of shock-positioning control systems for a variable-geometry inlet in combination with a J34 turbojet engine
- Report presenting shock-position controls designed to actuate the translating spike and variable bypass of a variable-geometry inlet in the 8- by 6-foot supersonic tunnel. The operation of the inlet was observed in combination with a J34 turbojet engine at a range of Mach numbers. Results regarding terminal-shock-positioning control systems and combination control are provided.
- Low-Amplitude Damping-in-Pitch Characteristics of Four Tailless Swept Wing-Body Combinations at Mach Numbers From 0.85 to 1.30 as Obtained With Rocket-Powered Models
- Report presenting an investigation to determine the damping-in-pitch characteristics of four rocket-powered wing-body combinations for a range of Mach numbers from 0.85 to 1.30. The models were tested at the same center-of-gravity location and had identical bodies. Information about the trim, lift, static longitudinal stability, dynamic longitudinal stability, and drag is provided.
- Experimental investigation of drag of afterbodies with exiting jet at high subsonic Mach numbers
- Report presenting an investigation to determine the pressure drag of various blunt-based conical afterbodies at a range of Mach numbers. A generalized series of bodies was included which incorporated convergent nozzles discharging unheated jets at various pressures from the base. Results regarding the afterbodies without the jet and afterbodies with the jet are provided.
- Investigation at Supersonic Speeds of the Effect of Jet Mach Number and Divergence Angle of the Nozzle Upon the Pressure of the Base Annulus of a Body of Revolution
- Report presenting an investigation in the 9-inch supersonic tunnel to determine the jet effects for varying jet Mach number and nozzle divergence angle upon the pressure on the base annulus of a model with a cylindrical afterbody. Testing occurred over a wide range of jet static pressure ratios and Mach numbers. Results regarding sonic jets and supersonic jets are provided.
- The effect of stick-force gradient and stick gearing on the tracking accuracy of a fighter airplane
- Report presenting steady straight-and-level and steady turning tracking runs against an aerial target using an F-51H airplane equipped with a fixed optical sight and with various combinations of maneuvering stick-force and stick-deflection gradients. Results regarding aim wander, elevator movement, and stick-force variation for various test conditions are provided.
- Steady-state and surge characteristics of a compressor equipped with variable inlet guide vanes operating in a turbojet engine
- Report presenting an investigation of a turbojet engine with variable inlet guide vanes in an altitude test facility to determine the steady-state compressor performance and surge characteristics. Compressor surge pressure ratios were found to be unaffected by changes in flight condition for either position of the inlet guide vanes. Decreasing the inlet Reynolds number was found to reduce the corrected fuel flow required for compressor surge.
- Investigation of Supersonic-Compressor Rotors Designed with External Compression
- Report presenting an investigation of the possibility of utilizing the relatively good characteristics of the spike-type diffuser in the supersonic compressor. Results regarding the overall performance, inlet conditions, outlet conditions, entrance flow conditions, and estimated performance of subsonic portion of rotor passage are provided.
- The Effect of Wing Profile on the Transonic Characteristics of Rectangular and Triangular Wings Having Aspect Ratios of 3: Transonic Bump Technique
- Report presenting an investigation to determine the effect of wing profile on the transonic aerodynamic characteristics of rectangular and triangular wings with aspect ratios of 3. Five wings were compared over a range of Mach and Reynolds number. Results regarding the rectangular and triangular wings and use of transonic area rule are provided.
- A flight investigation at transonic speeds and small angles of attack of the aerodynamic characteristics of a model having a 45 degree sweptback wing of aspect ratio 3 with an Naca 64A006 airfoil section
- Report presenting an investigation of the longitudinal aerodynamic characteristics of a model with a 45 degree sweptback wing of aspect ratio 3 and a 45 degree sweptback cruciform tail at transonic speeds and small angles of attack by a free-fall recoverable-model technique. Results regarding lift, drag, static longitudinal stability, dynamic longitudinal stability, and loading distribution over the fuselage are provided.
- Effects of angle of attack and airfoil profile on the two-dimensional flutter derivatives for airfoils oscillating in pitch at high subsonic speeds
- Report presenting two-dimensional aerodynamic lift and moment flutter derivatives for moderate and high angles of attack for several airfoil profiles varying in thickness and thickness distribution. The results indicate that the variables angle of attack, airfoil profile, reduced frequency, and Mach number all have significant interdependent effects.
- Sea-level static equilibrium performance of actual two-spool turbojet engine and comparison with hypothetical engine
- Report presenting an evaluation of the sea-level static equilibrium performance of an early developmental two-spool turbojet engine and its components and a comparison with a hypothetical two-spool turbojet engine. Results regarding the equilibrium performance of the actual engine, including its compressor performance, turbine performance, component operation, and engine performance and a comparison of those categories with the hypothetical engine are provided.
- Low-Speed Measurements of Rolling and Yawing Stability Derivatives of a 60 Degree Delta-Wing Model
- Memorandum presenting an investigation in the free-flight tunnel to determine the low-speed rolling and yawing stability derivatives of a 60 degree delta-wing model from 0 to 30 degrees angle of attack. The derivatives were measured by the free-to-damp oscillation technique and by the steady-roll technique.
- Experimental Investigation of a 0.4 Hub-Tip Diameter Ratio Axial-Flow Compressor Inlet Stage at Transonic Inlet Relative Mach Numbers 2: Stage and Blade-Element Performance
- Memorandum presenting an investigation to determine the feasibility of increasing the specific weight flow of a transonic axial-flow compressor inlet stage by decreasing the hub-tip ratio. The current phase of the investigation was conducted to determine the blade-element and the overall performance of the complete stage. Results regarding the overall performance, blade-element performance, and stator-blade-element performance are provided.
- Lift and drag characteristics of the Douglas X-3 research airplane obtained during demonstration flights to a Mach number of 1.20
- Report presenting lift and drag data obtained during the Douglas X-3 airplane. The data covered the Mach number range from 0.82 to 1.20 with considerable variation in lift. A comparison of the flight data with data from wind-tunnel and rocket-model tests shows that the model tests adequately predict the performance of the airplane.
- Results of initial wind-tunnel flutter experiments at low speed with a towed airplane model having a 40 degree sweptback wing of aspect ratio 3.62 equipped with pylon-mounted stores
- Report presenting wind-tunnel flutter testing at a range of Mach numbers conducted on a swept-wing towed airplane model equipped with an autopilot system. Results regarding the towed model tests, fixed-root tests, and a comparison between the calculated and experimental flutter characteristics are provided.
- Effects of Secondary-Air Flow on Annular Base Force of a Supersonic Airplane
- Memorandum presenting an investigation of the effect of base bleed on the base force of a supersonic-interceptor model in the 8- by 6-foot supersonic wind tunnel. Two groups of fixed-geometry nozzles and shroud combinations simulating double-iris-type configurations were evaluated over a range of secondary to primary exit-diameter ratios.
- Investigation of Two Short Annular Diffuser Configurations Utilizing Section and Injection as a Means of Boundary-Layer Control
- Memorandum presenting an investigation of the performances of two annular diffuser designs applicable to turbojet afterburner installations to determine the effectiveness of injection and suction boundary-layer controls. Results regarding inlet measurements, flow observations, static-pressure distributions, downstream velocity distributions, and mean performance coefficients are provided.
- 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.
- Additional experimental heat-transfer and durability data on several forced-convection, air-cooled, strut-supported turbine blades of improved design
- Report presenting an investigation at the Lewis laboratory to develop air-cooled, strut-supported turbine blades. Six blades were investigated in a full-scale turbojet engine to obtain data on blade durability and blade-cooling effectiveness and strut temperature. Results regarding the heat-transfer investigation and blade-durability investigation are provided.
- A preliminary investigation of the use of circulation control to increase the lift of a 45 degree sweptback wing by suction through trailing-edge slots
- Report presenting an investigation to determine the effectiveness of circulation control by applying suction through trailing-edge slots on a 45 degree sweptback wing. Various chordwise extents and depths of slot were investigated with and without deflection of a trailing-edge split flap. Results regarding the correlation of two-dimensional-section results with Ehlers' theory, effectiveness of circulation control on a sweptback wing, effect of slot configuration on circulation control, effect of trailing-edge split flap on circulation control, effect of circulation control on pitching moment, and circulation control at angle of attack are provided.
- 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.
- Effect on the low-speed aerodynamic characteristics of a 49 degree sweptback wing having an aspect ratio of 3.78 of blowing air over the trailing-edge flap and aileron
- Report presenting an investigation in the full-scale tunnel to determine the effects on the aerodynamic characteristics of a 49.1 degree sweptback wing of blowing a high-energy stream of air over a trailing-edge flap and an aileron. The results indicated that significant increases in lift coefficient and an improvement in aileron effectiveness may be obtained by the blowing method of boundary-layer control.
- Wind-tunnel investigation of the effect of clipping the tips of triangular wings of different thickness, camber, and aspect ratio - transonic bumb method
- Report presenting an investigation on a transonic bump to determine the aerodynamic characteristics of a series of triangular wings. Four basic triangular-wing plan forms with different aspect ratios, taper ratios, and combinations of tip clipping were tested over a range of Mach and Reynolds numbers. Results regarding angle of attack, drag coefficient, pitching-moment coefficient with lift coefficient, and various curves are provided.
- Application of Pulse Techniques to Strain Gages
- Memorandum presenting pulse techniques applied to strain gages for increasing the output level and extending the usable range. Bonded and unbonded strain gages which normally operate with exciting potentials between 3.5 and 14 volts operated satisfactorily with 200-volt pulses of 1-microsecond duration and a repetition rate of 350 per second. Results regarding maximum allowable voltages, effective pulse duration, sensitivity, minimum readable signal, effects of cable capacitance and inductance, sensitivity to external noise, and linearity are provided.
- Altitude performance of compressor, combustor, and turbine components of XT38-A-2 turboprop engine
- From Introduction: "The overall performance and operational characteristics are reported in reference 1. The performance of the components (compressor, combustor, turbine) is reported herein."
- Effect of wing flexibility on the damping roll of a notched delta-wing body combination between Mach numbers 0.6 and approximately 2.2 as determined with rocket-propelled models
- Report presenting an investigation with sting-mounted rocket-propelled models in free flight at approximately zero lift to determine the effect of wing flexibility on the damping-in-roll characteristics of a wing-body combination over a range of Mach numbers.
- Engine performance of alloy 73J turbine blades cast to predetermined grain sizes
- Report presenting an investigation to determine the suitability of alloy 73J as a turbojet turbine-blade alloy and the effect of grain size on engine operating life. Blades made of alloy 73J were run in a full-scale J33-9 turbojet engine under cyclic conditions. Results regarding the macroexamination of blades, engine life, engine life against stress-rupture life, blade failures, blade elongation, metallographic results, and blade dimensions and the possible effects of overdimensions are provided.