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Ability of Pilots to Control Simulated Short-Period Yawing Oscillations (open access)

Ability of Pilots to Control Simulated Short-Period Yawing Oscillations

Report discussing an investigation into the ability of human pilots to control short-period yawing oscillations using a yaw simulating device. The ability to control the oscillations was determined to be a function of period, control effectiveness, and inherent damping. Pilot control effectiveness was found to improve with practice.
Date: November 13, 1950
Creator: Phillips, William H. & Cheatham, Donald C.
System: The UNT Digital Library
Aerodynamic Characteristics at High Speeds of Full-Scale Propellers Having Different Shank Designs (open access)

Aerodynamic Characteristics at High Speeds of Full-Scale Propellers Having Different Shank Designs

"Tests of two 10-foot-diameter two-blade propellers which differed only in shank design have been made in the Langley 16-foot high-speed tunnel. The propellers are designated by their blade design numbers, NACA 10-(5)(08)-03, which had aerodynamically efficient airfoil shank sections, and NACA 10-(5)(08)-03R which had thick cylindrical shank sections typical of conventional blades. The propellers mere tested on a 2000-horsepower dynamometer through a range of blade-angles from 20 degrees to 55 degrees at various rotational speeds and at airspeeds up to 496 miles per hour" (p. 1).
Date: February 13, 1947
Creator: Maynard, Julian D.
System: The UNT Digital Library
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 (open access)

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.
Date: June 13, 1951
Creator: Polhamus, Edward C. & King, Thomas J., Jr.
System: The UNT Digital Library
Aerodynamic Characteristics of Three Deep-Stepped Planing-Tail Flying-Boat Hulls (open access)

Aerodynamic Characteristics of Three Deep-Stepped Planing-Tail Flying-Boat Hulls

"An investigation was made in the Langley 300 MPH 7- by 10-foot tunnel to determine the aerodynamic characteristics of three deep-stepped planing-tail flying-boat hulls differing only in the amount of step fairing. The hulls were derived by increasing the unfaired step depth of a planing-tail hull of a previous aerodynamic investigation to a depth about 92 percent of the hull beam. Tests were also made on a transverse-stepped hull with an extended afterbody for the purpose of comparison and in order to extend and verify the results of a previous investigation" (p. 1).
Date: March 13, 1947
Creator: Riebe, John M. & Naeseth, Rodger L.
System: The UNT Digital Library
Aerodynamics of bodies, wings, and wing-body combinations at high angles of attack and supersonic speeds (open access)

Aerodynamics of bodies, wings, and wing-body combinations at high angles of attack and supersonic speeds

From Introduction: "The primary purpose of this paper is to describe progress in the aerodynamics of wings, bodies, and wing-body combinations at high angles of attack."
Date: February 13, 1956
Creator: Nielsen, Jack N.; Spahr, J. Richard & Centolanzi, Frank
System: The UNT Digital Library
Aerodynamics of slender bodies at Mach number of 3.12 and Reynolds numbers from 2 x 10(exp 6) to 15 x 10(exp 6) 1: body of revolution with near-parabolic forebody and cylindrical afterbody (open access)

Aerodynamics of slender bodies at Mach number of 3.12 and Reynolds numbers from 2 x 10(exp 6) to 15 x 10(exp 6) 1: body of revolution with near-parabolic forebody and cylindrical afterbody

An experimental investigation of the aerodynamic characteristics of a slender, square-based body of revolution was conducted at a Mach number of 3.12 for angles of attack from 0 degree to 10 degrees and for Reynolds numbers from 2 x 10(exp 6) to 15 x 10(exp 6). Boundary-layer measurements at zero angle of attack are compared with several compressible flow formulating for predicting boundary-layer characteristics. Comparison of experimental pressure and force values with theoretical values showed good agreement for low angles of attack. The measured mean skin-friction coefficients agreed well with those predicted by Mangler's transformation for laminar flow over cones.
Date: November 13, 1951
Creator: Jack, John R. & Burgess, Warren C.
System: The UNT Digital Library
Altitude Acceleration Investigation of the RA-14 Avon Turbojet Engine (open access)

Altitude Acceleration Investigation of the RA-14 Avon Turbojet Engine

As a part of this investigation, the acceleration characteristics of the engine, using the standard engine fuel-control system, were obtained for conditions simulating flight at altitudes of 35,000 and 50,000 feet with a flight Mach number of 0.4. Rapid and wave-off type accelerations were made at each flight condition, and the transient performance of the engine was recorded with a multiple-channel oscillograph. The parameters are presented graphically in the form of time histories, augmented by short segments of the oscillograph recordings, in order to more completely describe the behavior of the engine parameters when surge was encountered.
Date: March 13, 1956
Creator: Russey, Robert E.
System: The UNT Digital Library
Altitude Performance of Modified J71 Afterburner with Revised Engine Operating Conditions (open access)

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."
Date: June 13, 1955
Creator: Useller, James W. & Russey, Robert E.
System: The UNT Digital Library
Altitude-wind-tunnel investigation of tail-pipe burning with a Westinghouse X24C-4B axial-flow turbojet engine (open access)

Altitude-wind-tunnel investigation of tail-pipe burning with a Westinghouse X24C-4B axial-flow turbojet engine

From Summary: "Thrust augmentation of an axial-flow type turbojet engine by burning fuel in the tail pipe has been investigated in the NACA Cleveland altitude wind tunnel. The performance was determined over a range of simulated flight conditions and tail-pipe fuel flows. The engine tail pipe was modified for the investigation to reduce the gas velocity at the inlet of the tail-pipe combustion chamber and to provide an adequate seat for the flame; four such modifications were investigated."
Date: December 13, 1948
Creator: Fleming, William A. & Wallner, Lewis E.
System: The UNT Digital Library
Analytical and experimental investigation of inlet-engine matching for turbojet-powered aircraft at Mach numbers up to 2.0 (open access)

Analytical and experimental investigation of inlet-engine matching for turbojet-powered aircraft at Mach numbers up to 2.0

An analysis of inlet-turbojet-engine matching for a range of Mach numbers up to 2.0 indicates large performance penalties when fixed-geometry inlets are used. Use of variable-geometry inlets, however, nearly eliminates th The analysis was confirmed experimentally by investigating at Mach numbers of 0, 0.63, and 1.5 to 2.0 two single oblique-shock-type inlets of different compression-ramp angles, which simulated a variable-geometry configuration. The experimental investigation indicated that total-pressure recoveries comparable withose attainable with well designed nose inlets were obtained with the side inlets when all the boundary layer ahead of the inlets was removed. Serious drag penalties resulted at a Mach number of 2.0 from the use of blunt-cowl leading edges. However, sharp-lip inlets produced large losses in thrust for the take-off condition. These thrust penalties which are associated with the the low-speed operation of the sharp-lip inlet designs can probably be avoided without impairing the supersonic performance of the inlet by the use of auxiliary inlets or blow-in doors.
Date: February 13, 1952
Creator: Schueller, Carl F. & Esenwein, Fred T.
System: The UNT Digital Library
Analytical and experimental investigation of thrust augmentation of axial- and centrifugal-compressor turbojet engines by injection of water and alcohol in combustion chambers (open access)

Analytical and experimental investigation of thrust augmentation of axial- and centrifugal-compressor turbojet engines by injection of water and alcohol in combustion chambers

Report presenting an investigation of thrust augmentation by injection of water and water-alcohol mixtures in the combustion chambers at sea-level zero-ram flight conditions on 4000-pound-thrust axial-flow and centrifugal-flow turbojet engines. Thrust augmentation, compressor characteristics, fuel flow, and turbine-outlet-temperature distributions are presented for various injection rates and water-alcohol mixtures.
Date: April 13, 1950
Creator: Gabriel, David S.; Dowman, Harry W. & Jones, William L.
System: The UNT Digital Library
Analytical Investigation of Propeller Efficiency at High Subsonic Flight Speeds near Mach Number Unity (open access)

Analytical Investigation of Propeller Efficiency at High Subsonic Flight Speeds near Mach Number Unity

From Introduction: "Tests have recently been conducted in the Langley 8-foot high-speed tunnel (reference 1) to study the effects of changes in operating advance ratio, blade plan form, blade-section thickness, section camber, and other variables on the on the propeller characteristics in the transonic-speed range. The method in reference 2, which evaluated the profile drag losses and the induced losses seperately, is followed in this paper. The method as presented offers the general prediction of propeller performance, and can be used to supplement the experimental data."
Date: February 13, 1950
Creator: Gilman, Jean, Jr.; Crigler, John L. & McLean, F. Edward
System: The UNT Digital Library
An Anaylsis of Control Requirements and Control Parameters for Direct-Coupled Turbojet Engines (open access)

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).
Date: June 13, 1947
Creator: Novik, David & Otto, Edward W.
System: The UNT Digital Library
Angle-of-attack-supersonic performance of a configuration consisting of a ramp-type scoop inlet located either on top or bottom of a body of revolution (open access)

Angle-of-attack-supersonic performance of a configuration consisting of a ramp-type scoop inlet located either on top or bottom of a body of revolution

From Introduction: "In reference 1, in which the performance of conical supersonic scoop inlets on circular fuselages is reported, the drag of the bottom-inlet configuration was considerably higher than for the top inlet."
Date: May 13, 1954
Creator: Kremzier, Emil J. & Campbell, Robert C.
System: The UNT Digital Library
Application of Tchebichef form of harmonic analysis to the calculation of zero-lift wave drag of wing-body-tail combinations (open access)

Application of Tchebichef form of harmonic analysis to the calculation of zero-lift wave drag of wing-body-tail combinations

Report presenting an improvement of the computing procedure of NACA RM A53H17 using a new procedure of harmonic analysis using Tchebichef polynominals. The two main improvements are the simplification of computing procedures and the provision for a comprehensive check solution which includes a direct check of how well the number of harmonics used represent the area-distribution curve.
Date: February 13, 1956
Creator: Holdaway, George H. & Mersman, William A.
System: The UNT Digital Library
Calculated effects of turbine rotor-blade cooling-air flow, altitude, and compressor bleed point on performance of a turbojet engine (open access)

Calculated effects of turbine rotor-blade cooling-air flow, altitude, and compressor bleed point on performance of a turbojet engine

Effects of air-cooling turbine rotor blades on performance of a turbojet engine were calculated for a range of altitudes from sea level to 40,000 feet and a range of coolant flows up to 3 percent of compressor air flow, for two conditions of coolant bleed from the compressor. Bleeding at required coolant pressure resulted in a sea-level thrust reduction approximately twice the percentage coolant flow and in an increase in specific fuel consumption approximately equal to percentage coolant flow. For any fixed value of coolant flow ratio the percentage thrust reduction and percentage increase in specific fuel consumption decreased with altitude. Bleeding coolant at the compressor discharge resulted in an additional 1 percent loss in performance at sea level and in smaller increase in loss of performance at higher altitudes.
Date: August 13, 1951
Creator: Arne, Vernon L. & Nachtigall, Alfred J.
System: The UNT Digital Library
Chordwise and Spanwise Loadings Measured at a Large Triangular Wing Having an Aspect Ratio of 2 and a Thin, Subsonic-Type Airfoil Section (open access)

Chordwise and Spanwise Loadings Measured at a Large Triangular Wing Having an Aspect Ratio of 2 and a Thin, Subsonic-Type Airfoil Section

Memorandum presenting pressure-distribution and force data at various angles of attack of a triangular wing of aspect ratio 2 and having an NACA 0005 modified section. The wing had a plain, constant-chord, trailing-edge flap which was deflected 0 and 10 degrees. Results regarding the gross force characteristics of the wing, including lift, drag, pitching-moment, and flap hinge-moment coefficients are provided.
Date: March 13, 1950
Creator: Graham, David
System: The UNT Digital Library
Combustion efficiencies in hydrocarbon-air systems at reduced pressures (open access)

Combustion efficiencies in hydrocarbon-air systems at reduced pressures

Report presenting results obtained with quiescent fuel-air mixtures and with small diffusion flames, which indicate that combustion efficiencies close to 100 percent were obtained at pressure much lower than those found in turbojet combustors at altitudes of 60,000 feet.
Date: September 13, 1950
Creator: Hibbard, Robert R.; Drell, Isadore L.; Metzler, Allen J. & Spakowski, Adolph E.
System: The UNT Digital Library
Comparison of Wind-Tunnel Predictions with Flight Measurements of the Longitudinal-Stability and -Control Characteristics of a Douglas BTD-1 Airplane (open access)

Comparison of Wind-Tunnel Predictions with Flight Measurements of the Longitudinal-Stability and -Control Characteristics of a Douglas BTD-1 Airplane

"Low Mach number longitudinal-stability and control characteristics as predicted by use of wind tunnel data from a powered 3/16-scale model are compared with flight test measurements of a Navy BTD-1 airplane. The accuracy of the wind tunnel data and the discrepancies involved in attempting to correlate with flight data are discussed and analyzed. The comparison showed that wind tunnel predictions were, in general, in good agreement with flight test data" (p. 1).
Date: February 13, 1947
Creator: Bunnell, Mort V. & Delany, Noel K.
System: The UNT Digital Library
Cooling of gas turbines 9: cooling effects from use of ceramic coatings on water-cooled turbine blades (open access)

Cooling of gas turbines 9: cooling effects from use of ceramic coatings on water-cooled turbine blades

From Summary: "The hottest part of a turbine blade is likely to be the trailing portion. When the blades are cooled and when water is used as the coolant, the cooling passages are placed as close as possible to the trailing edge in order to cool this portion. In some cases, however, the trailing portion of the blade is so narrow, for aerodynamic reasons, that water passages cannot be located very near the trailing edge. Because ceramic coatings offer the possibility of protection for the trailing part of such narrow blades, a theoretical study has been made of the cooling effect of a ceramic coating on: (1) the blade-metal temperature when the gas temperature is unchanged, and (2) the gas temperature when the metal temperature is unchanged."
Date: October 13, 1948
Creator: Brown, W. Byron & Livingood, John N. B.
System: The UNT Digital Library
Ditching investigation of a 1/25-scale model of a 255,000-pound transport airplane (open access)

Ditching investigation of a 1/25-scale model of a 255,000-pound transport airplane

"An investigation was made of a 1/25-scale dynamically similar model of a 255,000-pound transport airplane in order to study its behavior when ditched. The model was free-launched from the Langley tank no. 2 monorail carriage into calm water. Various landing attitudes, flap settings, speeds, and configurations were investigated" (p. 1).
Date: July 13, 1955
Creator: Windham, John O.
System: The UNT Digital Library
Drag at Model Trim Lift of a 1/15-Scale Convair B-58 Supersonic Bomber (open access)

Drag at Model Trim Lift of a 1/15-Scale Convair B-58 Supersonic Bomber

Report presenting an investigation using rocket-propelled model of the Convair B-58 supersonic bomber. Drag at trim lift was obtained for a range of Mach and Reynolds numbers and is compared to data from several other testing facilities.
Date: July 13, 1956
Creator: Hopko, Russell N. & Kinard, William H.
System: The UNT Digital Library
Drag at Model Trim Lift of a 1/15-Scale Convair B-58 Supersonic Bomber (open access)

Drag at Model Trim Lift of a 1/15-Scale Convair B-58 Supersonic Bomber

Memorandum presenting an investigation utilizing a 1/15-scale rocket-propelled model of the Convair B-58 supersonic bomber. The drag at model trim lift was obtained at a range of Mach and Reynolds numbers. A comparison of the drag at transonic speeds and approximately the same Reynolds number showed excellent agreement.
Date: July 13, 1956
Creator: Hopko, Russell N. & Kinard, William H.
System: The UNT Digital Library
Drag of a Wing-Body Configuration Consisting of a Swept-Forward Tapered Wing Mounted on a Body of Fineness Ratio 12 Measured During Free Fall at Transonic Speeds (open access)

Drag of a Wing-Body Configuration Consisting of a Swept-Forward Tapered Wing Mounted on a Body of Fineness Ratio 12 Measured During Free Fall at Transonic Speeds

Report discussing an investigation to determine the drag of a configuration with a body of fitness ratio 12 with stabilizing tail surfaces and a 12-percent-thick 30-degree swept-forward wing using the free-fall method. The drag oft he wing and the total drag were measured separately and compared. The swept-forward wing was found to greatly increase the effect of drag on the body-tail combination.
Date: March 13, 1947
Creator: Thompson, Jim Rogers & Mathews, Charles W.
System: The UNT Digital Library