Comparative Drag Measurements at Transonic Speeds of 6-Percent-Thick Airfoils of Symmetrical Double-Wedge and Circular-Arc Sections From Tests by the NACA Wing-Flow Method (open access)

Comparative Drag Measurements at Transonic Speeds of 6-Percent-Thick Airfoils of Symmetrical Double-Wedge and Circular-Arc Sections From Tests by the NACA Wing-Flow Method

Report presenting comparative drag measurements at zero lift at transonic speeds for two sharp-leading-edge airfoils using the NACA wing-flow method. One airfoil had a symmetrical circular-arc section and one had a symmetrical double-wedge section. The primary difference in the drag characteristics of the two airfoils at zero lift is the earlier drag rise of the double-wedge section.
Date: April 8, 1947
Creator: Silsby, Norman S.
System: The UNT Digital Library
Comparison of the transonic drag characteristics of two wing-body combinations differing only in the location of the 45 degree sweptback wing (open access)

Comparison of the transonic drag characteristics of two wing-body combinations differing only in the location of the 45 degree sweptback wing

Report presenting the drag of a series of wing-body combinations by the free-fall method in order to provide information on the drag characteristics of promising transonic and supersonic airplane arrangements. Time histories, Mach number variations, and drag coefficients for several areas of the body are provided.
Date: December 8, 1947
Creator: Mathews, Charles W. & Thompson, Jim Rogers
System: The UNT Digital Library
Investigation of Effects of Several Fuel-Injection Locations on Operational Performance of a 20-Inch Ram Jet (open access)

Investigation of Effects of Several Fuel-Injection Locations on Operational Performance of a 20-Inch Ram Jet

Report presenting the results of an investigation to determine the effects of several methods of fuel injection on the operational performance of a 20-inch ram jet. Four fuel-injection arrangements using the same flame holder were presented. Results regarding the variation of combustion efficiency, ram-pressure ratio, location of the point of fuel injection, and range of fuel-air ratios over which combustion can be maintained are provided.
Date: June 8, 1948
Creator: Sterbentz, W. H.; Perchonok, E. & Wilcox, F. A.
System: The UNT Digital Library
Notes on Geared Tabs at Supersonic Speeds (open access)

Notes on Geared Tabs at Supersonic Speeds

Memorandum presenting an analysis of the two-dimensional, geared, trailing-edge flap-tab combination at supersonic speeds to determine if the combination could be used to reduce the hinge moments to extremely small values while retaining a large part of the lift effectiveness of a plain flap with the same ratio of flap chord to wing chord.
Date: July 8, 1948
Creator: Tucker, Warren A.
System: The UNT Digital Library
Drag Measurements of a Swept-Back Wing Having Inverse Taper as Determined by Flight Tests at Supersonic Speeds (open access)

Drag Measurements of a Swept-Back Wing Having Inverse Taper as Determined by Flight Tests at Supersonic Speeds

Report discussing the results of flight tests to determine the drag at zero lift of a swept-back wing of inverse taper using an NACA 65-009 airfoil. The data was compared to untapered wings with a similar degree of sweepback. The tapered wing was found to have a lower drag coefficient than the 34-degree swept-back untapered wing but a higher drag coefficient than the 45-degree swept-back untapered wing.
Date: April 8, 1947
Creator: Alexander, Sidney R.
System: The UNT Digital Library
Experimental investigation of thrust augmentation of axial-flow-type 4000-pound-thrust turbojet engine by water and alcohol injection at compressor inlet (open access)

Experimental investigation of thrust augmentation of axial-flow-type 4000-pound-thrust turbojet engine by water and alcohol injection at compressor inlet

Report presenting an experimental investigation of thrust augmentation of an axial-flow-type turbojet engine with a 4000-pound-thrust rating using a water-alcohol injection at the compressor inlet at sea-level conditions and zero ram. Three injection systems were investigated in order to obtain satisfactory atomization and distribution of the injected liquids. Results regarding engine performance and engine operation are provided.
Date: July 8, 1948
Creator: Baron, Burnett; Dowman, Harry W. & Dackis, William C.
System: The UNT Digital Library
Estimated transonic flying qualities of a tailless airplane based on a model investigation (open access)

Estimated transonic flying qualities of a tailless airplane based on a model investigation

Report presenting an analysis of the estimated flying qualities of a tailless airplane with the wing quarter-chord line swept back 35 degrees in a range of Mach numbers based on tests of a model of the airplane in the 7- by 10-foot tunnel. Results regarding performance, longitudinal stability and control, and lateral stability and control are provided.
Date: June 8, 1949
Creator: Donlan, Charles J. & Kuhn, Richard E.
System: The UNT Digital Library
High-Speed Wind-Tunnel Tests of a 1/16-Scale Model of the D-558 Research Airplane: Longitudinal Stability and Control of the D-558-1 (open access)

High-Speed Wind-Tunnel Tests of a 1/16-Scale Model of the D-558 Research Airplane: Longitudinal Stability and Control of the D-558-1

Report presenting the results of pitching-moment and lift measurements on a model of the D-558-1 airplane with no nose-inlet flow at several tail and elevator settings at a range of Mach numbers. Information about the stability, control, and downwash results is provided.
Date: July 8, 1948
Creator: Wright, John B.
System: The UNT Digital Library
Ice protection of turbojet engines by inertia separation of water 2: single-offset-duct system (open access)

Ice protection of turbojet engines by inertia separation of water 2: single-offset-duct system

Investigation of a single-offset-duct system designed to prevent entrance of water into a turbojet engine was conducted on a half-scale nacelle model. An investigation was made to determine ram-pressure recovery and radial velocity profiles at the compressor section and icing characteristics of such a duct system. At a design inlet velocity of 0.77, the maximum ram-pressure recovery attained with effective water-separating inlet was 77 percent, which is considerably less than attainable with a direct-ram inlet. Continuous heating of the accessory-housing surface would be required for inlets that have a small ice storage space.
Date: June 8, 1948
Creator: von Glahn, Uwe
System: The UNT Digital Library
Model ditching investigation of the Douglas DC-4 and DC-6 airplanes (open access)

Model ditching investigation of the Douglas DC-4 and DC-6 airplanes

Report presenting the ditching characteristics of the Douglas DC-4 and DC-6 in a water tank. Dynamically similar models of 1/16 scale were used for the investigation, which was conducted in calm and rough water. The ditching characteristics and safest ditching procedures were determined by testing at various landing attitudes, speeds, and simulated conditions of damage.
Date: November 8, 1949
Creator: Fisher, Lloyd J. & Hoffman, Edward L.
System: The UNT Digital Library
Estimation of Range of Stability Derivatives for Current and Future Pilotless Aircraft (open access)

Estimation of Range of Stability Derivatives for Current and Future Pilotless Aircraft

Memorandum presenting an analysis made of the probable range of the stability parameters of present and future missiles. Included is a short review of the dynamic theory and some of the factors and assumptions influencing the stability derivatives and equations of motion.
Date: October 8, 1947
Creator: Pitkin, Marvin & Ankenbruck, Herman O.
System: The UNT Digital Library
Tests of the NACA 64-010 and 64A010 Airfoil Sections at High Subsonic Mach Numbers (open access)

Tests of the NACA 64-010 and 64A010 Airfoil Sections at High Subsonic Mach Numbers

Memorandum presenting aerodynamic characteristics of the NACA 64-010 and 64A010 airfoil sections as determined from wind-tunnel tests at Mach numbers from 0.3 to 0.9. Comparisons are made which indicate the only significant differences in the characteristics of the two sections to be a consistently greater lift-curve slope and an approximately 10-percent greater maximum section lift coefficient at Mach numbers above 0.7 for the NACA 64-010 airfoil section.
Date: July 8, 1949
Creator: Hemenover, Albert D.
System: The UNT Digital Library
Investigation of a Thin Wing of Aspect Ratio 4 in the Ames 12-Foot Pressure Wind Tunnel 5: Static Longitudinal Stability and Control Throughout the Subsonic Speed Range of a Semispan Model of a Supersonic Airplane (open access)

Investigation of a Thin Wing of Aspect Ratio 4 in the Ames 12-Foot Pressure Wind Tunnel 5: Static Longitudinal Stability and Control Throughout the Subsonic Speed Range of a Semispan Model of a Supersonic Airplane

Memorandum presenting wind-tunnel tests of a semispan model of a hypothetical supersonic airplane to determine the static longitudinal stability and control characteristics of the airplane throughout the range of subsonic Mach numbers up to 0.95. The model had a long slender fuselage and a wing and horizontal tail of aspect ratio 4 and taper ratio 0.5. Results regarding the force and moment characteristics, wing wake and effective downwash at the horizontal tail, effects of compressibility, and longitudinal characterisitcs with the flaps deflected are provided.
Date: December 8, 1949
Creator: Johnson, Ben H., Jr. & Rollins, Francis W.
System: The UNT Digital Library
An empirical criterion for fin stabilizing jettisonable nose sections of airplanes (open access)

An empirical criterion for fin stabilizing jettisonable nose sections of airplanes

"Investigations in the Langley 20-foot free-spinning tunnel of models of five jettisonable nose sections have shown that the airplane nose sections are inherently unstable but can be stabilized by the addition of suitable fins. An empirical criterion has been developed which indicates the fin area required for stabilizing an airplane jettisonable nose section" (p. 1).
Date: December 8, 1949
Creator: Scher, Stanley H.
System: The UNT Digital Library
Longitudinal Stability and Control Characteristics of a Semispan Model of a Supersonic Airplane Configuration at Transonic Speeds From Tests by the NACA Wing-Flow Method (open access)

Longitudinal Stability and Control Characteristics of a Semispan Model of a Supersonic Airplane Configuration at Transonic Speeds From Tests by the NACA Wing-Flow Method

Report presenting an investigation using the NACA wing-flow method to determine the longitudinal stability and control characteristics at transonic speeds of a semispan airplane model with a long slender fuselage, straight wing, and tail of low aspect ratio with faired symmetrical double-wedge airfoil sections. Measurements of the normal force and pitching moments at various angles of attack with five different stabilizer angles of incidence were recorded. The tests were carried out a range of Mach numbers.
Date: November 8, 1948
Creator: Silsby, Norman S. & McKay, James M.
System: The UNT Digital Library
Altitude performance of AN-F-58 fuels in J33-A-21 single combustor (open access)

Altitude performance of AN-F-58 fuels in J33-A-21 single combustor

Report discussing three fuels conforming to AN-F-58 specification were investigated in order to determine the influence of boiling temperatures and aromatic content on altitude performance in single combustor of a 4600-pound-thrust turbojet engine.
Date: April 8, 1949
Creator: Dittrich, Ralph T. & Jackson, Joseph L.
System: The UNT Digital Library
Some preliminary results in the determination of aerodynamic derivatives of control surfaces in the transonic speed range by means of a flush-type electrical pressure cell (open access)

Some preliminary results in the determination of aerodynamic derivatives of control surfaces in the transonic speed range by means of a flush-type electrical pressure cell

Report presenting the use of a flush-type electrical pressure cell for measuring rapidly changing aerodynamic forces on a fluttering control surface. The use of the cell is valuable for the measurement of the aerodynamic forces. Results regarding the individual cells, integrated results, resolution of aerodynamic moments, comparison of aerodynamic with inertia moments, and comparison of static and dynamic hinge moments are provided.
Date: October 8, 1948
Creator: Erickson, Albert L. & Robinson, Robert C.
System: The UNT Digital Library
Yaw Characteristics of a 52 Degree Sweptback Wing of NACA 64(Sub 1)-112 Section With a Fuselage and With Leading-Edge and Split Flaps at Reynolds Numbers From 1.93 X 10(Exp 6) to 6.00 X 10(Exp 6) (open access)

Yaw Characteristics of a 52 Degree Sweptback Wing of NACA 64(Sub 1)-112 Section With a Fuselage and With Leading-Edge and Split Flaps at Reynolds Numbers From 1.93 X 10(Exp 6) to 6.00 X 10(Exp 6)

Report presenting low-speed testing in the pressure tunnel to determine the aerodynamic characteristics in yaw of a 52 degree sweptback wing with aspect ratio 2.88 and taper ratio 0.625 with NACA 64(sub 1)-112 airfoil sections. Testing included an investigation of the effects on the lateral stability of a fuselage and leading-edge and split flaps. Results regarding the lateral stability parameters of a plain wing, effect of flaps on the lateral stability parameters, effect of scale, and airflow characteristics in the region of a vertical tail are provided.
Date: November 8, 1948
Creator: Salmi, Reino J.
System: The UNT Digital Library
Ice protection of turbojet engines by inertia separation of water 3: annular submerged inlets (open access)

Ice protection of turbojet engines by inertia separation of water 3: annular submerged inlets

Aerodynamic and icing studies were conducted on a one-half-scale model of an annular submerged inlet for use with axial-flow turbojet engines. Pressure recoveries, screen radial-velocity profiles, circumferential mass-flow variations, and icing characteristics were determined at the compressor inlet. In order to be effective in maintaining water-free induction air, the inlet gap must be extremely small and ram-pressure recoveries consequently are low, the highest achieved being 65 percent at inlet-velocity ratio of 0.86. All inlets exhibited considerable screen icing. Severe mass-flow shifts occurred at angles of attack.
Date: June 8, 1948
Creator: von Glahn, Uwe
System: The UNT Digital Library
Internal-Film Cooling of Rocket Nozzles (open access)

Internal-Film Cooling of Rocket Nozzles

Experiments were conducted with 1000-pound-thrust rocket engine to determine feasibility of cooling convergent-divergent nozzle by internal film of water introduced at nozzle entrance. Water flow of 3 percent of propellant flow reduced heat flow into nozzle to 55 percent of uncooled heat flow. Introduction of water by porous ring before nozzle resulted in more uniform coverage of nozzle than water introduced by single arrangement of 36 jets directed along nozzle wall. Water flow through porous ring of 3.5 percent of propellant flow stabilized wall temperature in convergent section but did not adequately cool throat or divergent sections.
Date: June 8, 1948
Creator: Sloop, J. L. & Kinney, George R.
System: The UNT Digital Library
Investigation at large scale of the pressure distribution and flow phenomena over a wing with the leading edge swept back 47.5 degrees having circular-arc airfoil sections and equipped with drooped-nose and plain flaps (open access)

Investigation at large scale of the pressure distribution and flow phenomena over a wing with the leading edge swept back 47.5 degrees having circular-arc airfoil sections and equipped with drooped-nose and plain flaps

Report presenting an investigation of the pressure distribution over a wing with the leading-edge swept back 47.5 degrees and with symmetrical circular-arc airfoil sections in the full-scale tunnel at a designated Mach and Reynolds number. The investigation included measurements of the surface static pressures along the chord for six spanwise stations, for a large angle-of-attack range, and for several angles of yaw.
Date: September 8, 1949
Creator: Lange, Roy H.; Whittle, Edward F., Jr. & Fink, Marvin P.
System: The UNT Digital Library
Analysis and Preliminary Investigation of Eddy-Current Heating for Icing Protection of Axial-Flow-Compressor Blades (open access)

Analysis and Preliminary Investigation of Eddy-Current Heating for Icing Protection of Axial-Flow-Compressor Blades

From Introduction: "An analysis of eddy currents in a compressor blade, the geometry of which has been limited to that of a flat plate for simplicity, is presented."
Date: August 8, 1949
Creator: Dallas, Thomas & Ellisman, C.
System: The UNT Digital Library
An Investigation of the Characteristics of an Unswept Wing of Aspect Ratio 4.01 in the Langley 8-Foot High-Speed Tunnel (open access)

An Investigation of the Characteristics of an Unswept Wing of Aspect Ratio 4.01 in the Langley 8-Foot High-Speed Tunnel

Report presenting an investigation of the characteristics of a low-aspect-ratio wing at high subsonic Mach numbers in the high-speed tunnel. The wing model had an NACA 65-108 airfoil section, an aspect ratio of 4.01, a taper ratio of 0.498, and no twist or dihedral. Results regarding normal-force characteristics, pitching-moment characteristics, and drag characteristics are provided.
Date: November 8, 1949
Creator: Bielat, Ralph P. & Cahn, Maurice S.
System: The UNT Digital Library
Damping-in-Roll Characteristics of a 42.7 Degree Sweptback Wing as Determined From a Wind-Tunnel Investigation of a Twisted Semispan Wing (open access)

Damping-in-Roll Characteristics of a 42.7 Degree Sweptback Wing as Determined From a Wind-Tunnel Investigation of a Twisted Semispan Wing

Report presenting an investigation to determine the damping-in-roll characteristics of a 42.7 degree sweptback wing using a linearly twisted wing to represent a rolling wing. Results regarding the effect of the airfoil contour, damping-in-roll coefficient, wing-tip helix angle, and theoretical results are provided.
Date: August 8, 1949
Creator: Lockwood, Vernard E.
System: The UNT Digital Library