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Application of Theodorsen's Theory to Propeller Design (open access)

Application of Theodorsen's Theory to Propeller Design

"A theoretical analysis is presented for obtaining by use of Theodorsen's propeller theory the load distribution along a propeller radius to give the optimum propeller efficiency for any design condition. Examples are included to illustrate the method of obtaining the optimum load distributions for both single-rotating and dual-rotating propellers" (p. 1).
Date: July 26, 1948
Creator: Crigler, John L.
System: The UNT Digital Library
Aerodynamic Characteristics at High and Low Subsonic Mach Numbers of the NACA 0012, 64₂-015, and 64₃-018 Airfoil Sections at Angles of Attack from -2 Degrees to 30 Degrees (open access)

Aerodynamic Characteristics at High and Low Subsonic Mach Numbers of the NACA 0012, 64₂-015, and 64₃-018 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.
Date: July 23, 1954
Creator: Critzos, Chris C.
System: The UNT Digital Library
Theoretical analysis of the motions of an aircraft stabilized in roll by a displacement-response, flicker-type automatic pilot (open access)

Theoretical analysis of the motions of an aircraft stabilized in roll by a displacement-response, flicker-type automatic pilot

Report presenting a general analysis that allows the rolling motions of an aircraft using a displacement-response, flicker-type automatic pilot to be determined. The system is not ideal for many stabilization problems due to inherent residual oscillations, but it offers a simple and economical solution in situations in which steady state oscillations are not a problem. Results regarding some general remarks, transient and steady states, stabilization boundaries, amplitude equations, and period equations are provided.
Date: July 7, 1948
Creator: Curfman, Howard J., Jr. & Gardner, William N.
System: The UNT Digital Library
Experimental investigation at supersonic speeds of twin-scoop duct inlets of equal area 3: inlet enclosing 37.2 percent of the maximum circumference of the forebody (open access)

Experimental investigation at supersonic speeds of twin-scoop duct inlets of equal area 3: inlet enclosing 37.2 percent of the maximum circumference of the forebody

Report presenting testing of a twin-scoop duct inlet that enclosed 37.2 percent of the forebody circumference at Mach numbers between 1.36 and 2.01. The approach to each scoop consisted of a ramp that deflected the flow to create an oblique shock wave in front of the duct entrance. Results regarding the inlet proportions, ramp angle, slots, and angle of incidence are provided.
Date: July 22, 1948
Creator: Davis, Wallace F. & Edwards, Sherman S.
System: The UNT Digital Library
Performance Evaluation of Reduced-Chord Rotor Blading as Applied to J73 Two-Stage Turbine 6: Stage Performance With Standard Rotor Blading at Inlet Conditions of 35 Inches of Mercury Absolute and 700 Degrees R (open access)

Performance Evaluation of Reduced-Chord Rotor Blading as Applied to J73 Two-Stage Turbine 6: Stage Performance With Standard Rotor Blading at Inlet Conditions of 35 Inches of Mercury Absolute and 700 Degrees R

Report presenting an evaluation of the stage performance of the J73 turbine on the basis of previous performance investigations of the first stages alone and of the two-stage turbines with standard and with reduced-chord rotor blading for a range of rotational speeds and pressure ratios. The results demonstrated that both of the two-stage turbines and first-stage turbines had comparable performance.
Date: July 11, 1957
Creator: Davison, Elmer H. & Schum, Harold J.
System: The UNT Digital Library
Stability and control characteristics obtained during demonstration of the Douglas X-3 research airplane (open access)

Stability and control characteristics obtained during demonstration of the Douglas X-3 research airplane

Report presenting flight tests performed using the Douglas X-3 research airplane during the manufacturer's demonstration program and U.S. Air Force evaluation. Tests were performed over a range of Mach numbers and altitudes. Longitudinal, lateral, and directional stability and control data were obtained during steady and maneuvering flight and are compared with wind-tunnel and rocket-model data in this report.
Date: July 21, 1955
Creator: Day, Richard E. & Fischel, Jack
System: The UNT Digital Library
Additional measurements of the low-speed static stability of a configuration employing three triangular wing panels and a body of equal length (open access)

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."
Date: July 25, 1955
Creator: Delany, Noel K.
System: The UNT Digital Library
A Preliminary Investigation of the Power Requirements of Slotted Test Sections (open access)

A Preliminary Investigation of the Power Requirements of Slotted Test Sections

Report presenting an investigation of the power requirements for slotted tunnels and methods of reducing these requirements. All pressure losses reported occurred in the region between the upstream end of the entrance ball and the entrance to the diffuser and in handling air taken in through the slotted wall. Results regarding auxiliary pumping and ejector pumping are provided.
Date: July 7, 1953
Creator: Dennard, John S.
System: The UNT Digital Library
Dynamic corrosion of a stainless-steel specimen by water at 500 degrees F using a toroid circulating apparatus (open access)

Dynamic corrosion of a stainless-steel specimen by water at 500 degrees F using a toroid circulating apparatus

A slug of air-saturated distilled water was circulated for 317 hours at a velocity of 15 feet per second in an AISI 347 stainless-steel toroid with a wall temperature of 500 F and a 30 F difference in temperature between the hot and cold sections. The depth of corrosion layer was 0.001 inch (0.028 in./yr) in the hot sector and 0.0007 inch (0.019 in./yr) in the cold sector; no mass transfer was observed. The results of gas,water,and X-ray diffraction analyses are given together with photomicrographs of sections taken from the hot and cold sections of the specimen.
Date: July 16, 1952
Creator: Desmon, Leland G. & Mosher, Don R.
System: The UNT Digital Library
Investigation of the Loads on a Conventional Front and Rear Sliding Canopy (open access)

Investigation of the Loads on a Conventional Front and Rear Sliding Canopy

"As one phase of a comprehensive canopy load investigation, conventional front and rear sliding canopies which are typified by installation on the SB2C-4E airplane, were tested in the Langley full-scale tunnel to determine the pressure distributions and the aerodynamic loads on the canopies. A preliminary analysis of the results of these tests is presented in this report. Plots are presented that show the distribution of pressure at four longitudinal stations through each canopy for a range of conditions selected to determine the effects of varying canopy position, yaw, lift coefficient, and power" (p. 1).
Date: July 9, 1947
Creator: Dexter, Howard E. & Rickey, Edward A.
System: The UNT Digital Library
Acceleration Characteristics of a Turbojet Engine With Variable-Position Inlet Guide Vanes (open access)

Acceleration Characteristics of a Turbojet Engine With Variable-Position Inlet Guide Vanes

Report presenting a study of the acceleration characteristics of a turbojet engine equipped with variable-position inlet guide vanes in the altitude test chamber. Maximum acceleration values for 3 engines of the same model were also obtained during testing and were found to differ as much as 50 percent. Results regarding the effect of fuel step size and inlet guide vane on acceleration, effect of flight condition, reproducibility of engine acceleration, compressor pressure ratio in relation to acceleration, and acceleration with inlet air distortion are provided.
Date: July 7, 1955
Creator: Dobson, W. F. & Wallner, Lewis E.
System: The UNT Digital Library
An assessment of the airplane drag problem at transonic and supersonic speeds (open access)

An assessment of the airplane drag problem at transonic and supersonic speeds

Report presenting the airplane drag problem at transonic and supersonic speeds. The area rule is shown to be a powerful tool that provides guidance for designers in selecting aerodynamic features compatible with low wave drag. Analytical methods have been developed that permit quantitative evaluation of the wave-drag level likely to be experienced with a given design.
Date: July 15, 1954
Creator: Donlan, Charles J.
System: The UNT Digital Library
Exploratory investigation of aerodynamic effects of external combustion of aluminum borohydride in airstream adjacent to flat plate in Mach 2.46 tunnel (open access)

Exploratory investigation of aerodynamic effects of external combustion of aluminum borohydride in airstream adjacent to flat plate in Mach 2.46 tunnel

Report presenting pressure distributions associated with stable combustion of aluminum borohydride in the supersonic stream adjacent to a short, 13-inch chord, and an extended, 25-inch chord, flat-plate model. High-speed direct and schileren motion pictures of the flame and associated shock waves were taken. Results regarding the description of the combustion and associated stream disturbances, static-pressure change at model reference surface caused by combustion, lift forces resulting from combustion, base pressure change caused by combustion, stream-parameter measurements during combustion, and surface temperature changes during combustion are provided.
Date: July 29, 1957
Creator: Dorsch, Robert G.; Serafini, John S. & Fletcher, Edward A.
System: The UNT Digital Library
Experimental performance of fluorine-oxygen with JP4 fuel in a rocket engine (open access)

Experimental performance of fluorine-oxygen with JP4 fuel in a rocket engine

Report presenting the performance increase resulting from the addition of fluorine to the oxygen-JP4 rocket propellant combination evaluated experimentally in a 1000-pound-thrust engine with 0, 30, and 70 percent of fluorine by weight in the oxidant. Maximum specific impulse values obtained were 259, 278, and 287 pound-seconds per pound, respectively, at a combustion pressure of 600 pounds per square inch absolute.
Date: July 7, 1955
Creator: Douglass, Howard W.
System: The UNT Digital Library
Preliminary Experiments on the Elastic Compressive Buckling of Plates With Integral Waffle-Like Stiffening (open access)

Preliminary Experiments on the Elastic Compressive Buckling of Plates With Integral Waffle-Like Stiffening

Memorandum presenting an experimental investigation of the elastic compressive buckling strength of plates with various configurations of integral stiffening. Some of the configurations tested included ribbing that was longitudinal, transverse, longitudinal, and transverse, and skewed at various angles to the sides of the plates to form a diamond or waffle-like pattern. The results indicate that the waffle-like stiffening is of sufficient structural interest to merit further study of the plastic buckling and fabrications aspects.
Date: July 28, 1952
Creator: Dow, Norris F. & Hickman, William A.
System: The UNT Digital Library
Altitude-Test-Chamber Investigation of a Solar Afterburner on the 24C Engine 1 - Operational Characteristics and Altitude Limits (open access)

Altitude-Test-Chamber Investigation of a Solar Afterburner on the 24C Engine 1 - Operational Characteristics and Altitude Limits

"An altitude-test-chamber investigation was conducted to determine the operational characteristics and altitude blow-out limits of a Solar afterburner in a 24C engine. At rated engine speed and maximum permissible turbine-discharge temperature, the altitude limit as determined by combustion blow-out occurred as a band of unstable operation of about 8000 feet altitude in width with maximum altitude limits from 32,000 feet at a Mach number of 0.3 to about 42,000 feet at a Mach number of 1.0. The maximum fuel-air ratio of the afterburner, as limited by maximum permissible turbine-discharge gas temperatures at rated engine speed, varied between 0.0295 and 0.0380 over a range of flight Mach numbers from 0.25 to 1.0 and at altitudes of 20,000 and 30,000 feet" (p. 1).
Date: July 6, 1948
Creator: Dowman, Harry W. & Reller, John O.
System: The UNT Digital Library
Operational problems of manned orbital vehicles (open access)

Operational problems of manned orbital vehicles

Report presenting an exploration of some of the problems of manned orbital vehicles, which introduce many problems in the fields of escape, piloting, orbit selection, flight termination, and range requirements. The effects of some of these problems, including some effects of configuration, are discussed.
Date: July 21, 1958
Creator: Drake, Hubert M.; Bellman, Donald R. & Walker, Joseph A.
System: The UNT Digital Library
Aerodynamic Characteristics at Supersonic Speeds of a Series of Wing-Body Combinations Having Cambered Wings With an Aspect Ratio of 3.5 and a Taper Ratio of 0.2: Effect at M = 2.01 of Nacelle Shape and Position on the Aerodynamic Characteristics in Pitch of Two Wing-Body Combinations with 47 Degree Sweptback Wings (open access)

Aerodynamic Characteristics at Supersonic Speeds of a Series of Wing-Body Combinations Having Cambered Wings With an Aspect Ratio of 3.5 and a Taper Ratio of 0.2: Effect at M = 2.01 of Nacelle Shape and Position on the Aerodynamic Characteristics in Pitch of Two Wing-Body Combinations with 47 Degree Sweptback Wings

Memorandum presenting an investigation at M = 2.01 in the 4- by 4-foot supersonic pressure tunnel to determine the effect of a series of nacelles on the longitudinal stability characteristics of a sweptback wing-body combination. Nacelle shape and position were varied on a configuration with a 6-percent-thick wing with an aspect ratio of 3.5, a taper ratio of 0.2, and 47 degrees of sweep at the quarter chord.
Date: July 25, 1952
Creator: Driver, Cornelius
System: The UNT Digital Library
Static longitudinal stability and control characteristics of a model of a 45 degree swept-wing fighter airplane at Mach numbers of 1.41, 1.61, and 2.01 (open access)

Static longitudinal stability and control characteristics of a model of a 45 degree swept-wing fighter airplane at Mach numbers of 1.41, 1.61, and 2.01

Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the static longitudinal stability and control characteristics of a model of a 45 degree swept-wing fighter airplane at three Mach numbers. The results indicate that the static margin, which was fairly constant through the lift range, decrease from 32 to 27 percent mean aerodynamic chord with increase in Mach number from 1.41 to 2.01.
Date: July 11, 1956
Creator: Driver, Cornelius & Foster, Gerald V.
System: The UNT Digital Library
Performance Characteristics of a Normal-Shock Side Inlet Located Downstream of a Canard Control Surface at Mach Numbers of 1.5 and 1.8 (open access)

Performance Characteristics of a Normal-Shock Side Inlet Located Downstream of a Canard Control Surface at Mach Numbers of 1.5 and 1.8

The performance characteristics of a downward canted normal-shock side (scoop) inlet located downstream of a triangular control surface are presented for free-stream Mach numbers of 1.5 and 1.8 in terms of total pressure recovery and mass flow ratio for various boundary-layer removal systems, angles of attack, control surface deflections and adverse yaw. An engine operating condition for a hypothetical turbojet engine is established, and the match point characteristics of the engine-inlet configuration are summarized. It is shown that the diffuser performance increases with increased boundary-layer removal and decreases because of the presence of the wake from the forward control surface.
Date: July 29, 1952
Creator: Dryer, Murray & Beke, Andrew
System: The UNT Digital Library
Effects of three types of blunt trailing edges on the aerodynamic characteristics of a plane tapered wing of aspect ratio 3.1, with a 3-percent- thick biconvex section (open access)

Effects of three types of blunt trailing edges on the aerodynamic characteristics of a plane tapered wing of aspect ratio 3.1, with a 3-percent- thick biconvex section

Report presenting effects of wing trailing-edge bluntness on aerodynamic characteristics of a wing-body combination at a range of Mach numbers and Reynolds numbers. Modifications were made to the rear half of a basic plane tapered wing of aspect ratio 3.1 and a 3-percent-thick, circular-arc, biconvex section with three types of trailing-edge shapes. Results regarding the lift characteristics, pitching-moment characteristics, drag characteristics, and maximum lift-drag ratio are provided.
Date: July 22, 1952
Creator: Dugan, Duane W.
System: The UNT Digital Library
Effect of Design Variables on Performance of Mach 4.0 Hydrogen Expansion Engines (open access)

Effect of Design Variables on Performance of Mach 4.0 Hydrogen Expansion Engines

Memorandum presenting performance calculations for hypothetical hydrogen expansion engines in which only a small part of the engine airflow passes through the heat exchanger. The flight path was representative of those for long-range, high-speed aircraft. Results regarding the off-design operation and engine performance are provided.
Date: July 22, 1958
Creator: Dugan, James F., Jr.
System: The UNT Digital Library
Effect of Design Variables on Performance of Mach 4.0 Hydrogen Expansion Engines (open access)

Effect of Design Variables on Performance of Mach 4.0 Hydrogen Expansion Engines

Memorandum presenting performance calculations made for hypothetical hydrogen expansion engines in which only a small part of the engine airflow passes through the heat exchanger. The prescribed flight path was representative of those for long-range, high-speed aircraft. Results regarding the off-design operation and engine performance are provided.
Date: July 22, 1958
Creator: Dugan, James F., Jr.
System: The UNT Digital Library
Analytical investigation of flow and heat transfer in coolant passages of free-convection liquid-cooled turbines (open access)

Analytical investigation of flow and heat transfer in coolant passages of free-convection liquid-cooled turbines

From Introduction: "An analytical investigation of the problems arising in connection with this cooling method was conducted at the NACA Lewis laboratory and is presented herein. This analysis investigates: (1) the smallest diameter hole that can be made without endangering the circulation of the liquid, and (2) methods of improving the circulation in a small-diameter hole."
Date: July 18, 1950
Creator: Eckert, E. R. G. & Jackson, Thomas W.
System: The UNT Digital Library