Experimental Flutter Results for Cantilever-Wing Models at Mach Numbers Up to 3.0 (open access)

Experimental Flutter Results for Cantilever-Wing Models at Mach Numbers Up to 3.0

Report presenting experimental flutter testing at Mach numbers up to 3.0 using cantilever-wing models with 0 to 60 degree sweepback and 60 degree delta-wing models. The main variables explored were the high Mach number and center-of-gravity location on flutter trends. The theoretical results for flutter analyses were noted to be lower than the experimental results.
Date: June 14, 1955
Creator: Tuovila, W. J. & McCarty, John Locke
System: The UNT Digital Library
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 (open access)

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.
Date: December 14, 1954
Creator: Cook, Woodrow L.; Griffin, Roy N., Jr. & Hickey, David H.
System: The UNT Digital Library
Some effects of aileron span, aileron chord, and wing twist on rolling effectiveness as determined by rocket-powered model tests and theoretical estimates (open access)

Some effects of aileron span, aileron chord, and wing twist on rolling effectiveness as determined by rocket-powered model tests and theoretical estimates

A determination of the variation of rolling effectiveness with spanwise aileron extent for full-chord ailerons on a sweptback wing over a range of Mach numbers. The test wings had NACA 65A006 airfoil sections, an aspect ratio of 4.0, 45 degrees sweepback at the quarter-chord line, and a taper ratio of 0.6. Results regarding ailerons and twisted wings are provided.
Date: September 14, 1954
Creator: Strass, H. Kurt & Tucker, Warren A.
System: The UNT Digital Library
Aspects of internal-flow-system design for helicopter propulsive units (open access)

Aspects of internal-flow-system design for helicopter propulsive units

A discussion of pertinent items related to the design of internal-flow systems for reciprocating engine, turbine engine, and pressure-jet installations in helicopters. The following items are emphasized: controllable exit and ram recovery for reciprocating-engine cooling, performance penalties possible in turbine-engine installations, the effects of high subsonic flow velocities on the performance of duct elements, and the effects of centrifugal forces on the flow in a ducted helicopter rotor.
Date: September 14, 1954
Creator: Henry, John R.
System: The UNT Digital Library
Effect of boundary-layer control and inlet lip shape on the performance of a twin-scoop air-induction system at Mach numbers from 0 to 1.9 (open access)

Effect of boundary-layer control and inlet lip shape on the performance of a twin-scoop air-induction system at Mach numbers from 0 to 1.9

Report presenting an experimental investigation to determine the effect of boundary-layer control and inlet lip shape on the performance of a side-inlet air-induction system for a fighter-type airplane. Two methods of boundary layer control and three inlet lip shapes were investigated at a range of Mach numbers and mass-flow ratios. Results regarding net propulsive thrust are also provided.
Date: February 14, 1956
Creator: Lazzeroni, Frank A. & Pfyl, Frank A.
System: The UNT Digital Library
A fuel-distribution control for gas-turbine engines (open access)

A fuel-distribution control for gas-turbine engines

"The principle of operation of a device to control the distribution of fuel to any number of discharge nozzles of a gas-turbine engine is presented. A description of an experimental model of the device and the results of a bench investigation are presented. This device controlled the flow to four discharge nozzles within 2 percent of perfect distribution over a wide range of fuel flow and was unaffected by uneven discharge-nozzle pressures" (p. 1).
Date: June 14, 1948
Creator: Gold, Harold & Straight, David M.
System: The UNT Digital Library
High-Speed Wind-Tunnel Investigation of a Sweptback Wing With an Added Triangular Area at the Center (open access)

High-Speed Wind-Tunnel Investigation of a Sweptback Wing With an Added Triangular Area at the Center

Report discussing an investigation of two sweptback wings of different plan form in order to determine the effects of adding a triangular area to the inboard section of a conventional sweptback wing as a way to create a wing with two stages of sweepback. Lift, drag, and pitching-moment characteristics are provided for a range of Mach numbers.
Date: January 14, 1949
Creator: Henry, Beverly Z., Jr.
System: The UNT Digital Library
The Effectiveness at High Speeds of a 10-Percent-Chord Plain Trailing-Edge Flap on the NACA 65-210 Airfoil Section (open access)

The Effectiveness at High Speeds of a 10-Percent-Chord Plain Trailing-Edge Flap on the NACA 65-210 Airfoil Section

This report contains the results of a high-speed wind-tunnel investigation of the effectiveness of a 10-percent-chord plain flap on the NACA 65-210 airfoil section. The results include an indication of the lift-producing characteristics and the effectiveness of the 10-percent-chord flap. From a comparison of the characteristics of the 10-percent-chord flap with those of a 20-percent-chord flap it was concluded that, although a reduction in flap-chord ratio from 0.20 to 0.10 lessens the severity of the effectiveness loss at supercritical speeds, the 20-percent-chord flap is more effective throughout the entire range of Mach numbers from 0.3 to 0.875.
Date: June 14, 1948
Creator: Ilk, Richard J.
System: The UNT Digital Library
Preliminary Investigation to Determine Propeller Section Characteristics by Measuring the Pressure Distribution on an NACA 10-(3)(08)-03 Propeller Under Operating Conditions (open access)

Preliminary Investigation to Determine Propeller Section Characteristics by Measuring the Pressure Distribution on an NACA 10-(3)(08)-03 Propeller Under Operating Conditions

"An investigation has been made in the Langley 16-foot high-speed tunnel to determine the propeller-section characteristics by measuring the pressure distribution on the airfoil sections of a rotating propeller. The pressures were measured at nine radial stations on an NACA 10-(3)(08)-03 design two-blade propeller. This paper presents the results of the pressure measurements in the form of normal-force and moment coefficients and covers a range of nominal angle of attack (simple blade element theory) from 0 degrees to 4 degrees for a section Mach number range of approximately 0.6 to 1.15 for the outboard stations and approximately 0.3 to 0.6 for inboard stations" (p. 1).
Date: July 14, 1948
Creator: Evans, Albert J. & Liner, George
System: The UNT Digital Library
Experimental Investigation of the Effect of Forebody Bluntness on the Pressure Recovery and Drag of a Twin-Scoop Inlet-Body Combination at Mach Numbers of 1.4 and 1.7 (open access)

Experimental Investigation of the Effect of Forebody Bluntness on the Pressure Recovery and Drag of a Twin-Scoop Inlet-Body Combination at Mach Numbers of 1.4 and 1.7

Memorandum presenting the pressure recovery, mass flow, and drag of a twin-scoop inlet-body combination measured at Mach numbers 1.4 and 1.7 at zero angle of attack. Tests were made of the inlet-body combination with an ogival forebody, an ogival forebody with a small amount of bluntness near the tip, and two forebodies of elliptical longitudinal section. Results regarding the effect of forebody bluntness on pressure recovery, effect of forebody bluntness on mass-flow ratio, and the effects of forebody bluntness on drag are provided.
Date: February 14, 1952
Creator: Stroud, John F.
System: The UNT Digital Library
A summary and analysis of the low-speed longitudinal characteristics of swept wings at high Reynolds number (open access)

A summary and analysis of the low-speed longitudinal characteristics of swept wings at high Reynolds number

Report presenting the low-speed longitudinal characteristics of swept wings derived from investigations at high Reynolds numbers. Two different types of flow separation, trialing-edge and leading-edge separation, are identified and discussed.
Date: August 14, 1952
Creator: Furlong, G. Chester & McHugh, James G.
System: The UNT Digital Library
The Use of Area Suction for the Purpose of Delaying Separation of Air Flow at the Leading Edge of a 63 Degree Swept-Back Wing: Effects of Controlling the Chordwise Distribution of Suction Air Velocities (open access)

The Use of Area Suction for the Purpose of Delaying Separation of Air Flow at the Leading Edge of a 63 Degree Swept-Back Wing: Effects of Controlling the Chordwise Distribution of Suction Air Velocities

Report discusses the results of an updated investigation into the effectiveness of area suction when used to prevent air-flow separation at the leading edge of a 63 degree swept-back wing. This new report investigates the results of tests with chordwise distribution of the suction-air velocities controlled to give lower total-flow quantity requirements. The primary focus is the delay effected in air-flow separation and improvements made on aerodynamic characteristics of a wing with area suction specifically designed for a lift coefficient of 0.77.
Date: January 14, 1952
Creator: Cook, Woodrow L. & Kelly, Mark W.
System: The UNT Digital Library
Spreading of Exhaust Jet From 16 Inch Ream Jet at Mach Number 2.0 (open access)

Spreading of Exhaust Jet From 16 Inch Ream Jet at Mach Number 2.0

"An investigation of the jet-spreading characteristics of a 16 inch ram-jet engine was conducted in the 8 by 6 foot supersonic tunnel at a Mach number of 2.0; both a converging nozzle having a contraction ratio of 0.71 and a cylindrical extension to the combustion chamber were used. The jet boundaries determined by means of pitot pressure surveys were compared with boundaries calculated from one-dimensional continuity and momentum relations. For the cylindrical nozzle, the jet reaches its maximum diameter, 4 percent greater than calculated, about 0.6 nozzle-exit diameter downstream of the nozzle exit" (p. 1).
Date: August 14, 1952
Creator: Wilcox, Fred & Pennington, Donald
System: The UNT Digital Library
Some fundamental aspects of nitric acid oxidants for rocket applications (open access)

Some fundamental aspects of nitric acid oxidants for rocket applications

From Summary: "The literature pertaining to the preparation, physical properties, corrosiveness, thermal stability, constitution, and analysis of various nitric acids is reviewed primarily with respect to their use as rocket oxidants. Conflicting data are evaluated and recommendations for additional experimental work are indicated. Reactions of nitric acid which could occur during the starting and steady-stage phases of rocket operation are discussed and probable mechanisms are selected on the basis of reported thermal and kinetic data."
Date: January 14, 1953
Creator: Ladanyi, Dezso J.; Miller, Riley O.; Karo, Wolf & Feiler, Charles E.
System: The UNT Digital Library
Spark ignition of flowing gases III : effect of turbulence promoter on energy required to ignite a propane-air mixture (open access)

Spark ignition of flowing gases III : effect of turbulence promoter on energy required to ignite a propane-air mixture

Report presenting an investigation to determine the effect of turbulence generated by different sizes of wire grid on the minimum spark-ignition energy of a flowing propane-air mixture. Gas-stream velocity, size of turbulence promoter, and distance from the promoter plate to the electrodes on minimum ignition energy were evaluated and the effects are shown in figures.
Date: January 14, 1953
Creator: Swett, Clyde C., Jr. & Donlon, Richard H.
System: The UNT Digital Library
The effects of sweepback on longitudinal characteristics of a 1/30-scale semispan model of the Bell X-5 airplane as determined from NACA wing-flow tests at transonic speeds (open access)

The effects of sweepback on longitudinal characteristics of a 1/30-scale semispan model of the Bell X-5 airplane as determined from NACA wing-flow tests at transonic speeds

Report presenting tests using the NACA wing-flow method to determine the effect of sweepback angle on the longitudinal characteristics of a scale semispan model of the Bell X-5 variable-sweep airplane at a range of Mach numbers. Lift, drag, and pitching moments were obtained for a range of angles of attack.
Date: November 14, 1952
Creator: Kolnick, Joseph J. & Kennedy, Robert M.
System: The UNT Digital Library
Low-Speed Wind-Tunnel Investigation of the Effects of Propeller Operation at High Thrust on the Longitudinal Stability and Trim of a Twin-Engine Airplane Configuration (open access)

Low-Speed Wind-Tunnel Investigation of the Effects of Propeller Operation at High Thrust on the Longitudinal Stability and Trim of a Twin-Engine Airplane Configuration

Report presenting an investigation to determine the effects of dual-rotation propeller operation at high thrust on the static longitudinal stability characteristics of a semispan powered model representing a twin-engine airplane configuration with flaps retracted. Stability and trim changes associated with an extreme constant power conditions were greatly dependent on tail height and vertical location of the center of gravity. Results regarding basic data, effects of power on overall stability and trim, and tuft-grid flow surveys are provided.
Date: July 14, 1952
Creator: Sleeman, William C., Jr. & Linsley, Edward L.
System: The UNT Digital Library
Control Hinge-Moment and Effectiveness Characteristics of a 60 Degree Half-Delta Tip Control on a 60 Degree Delta Wing at Mach Numbers of 1.41 and 1.96 (open access)

Control Hinge-Moment and Effectiveness Characteristics of a 60 Degree Half-Delta Tip Control on a 60 Degree Delta Wing at Mach Numbers of 1.41 and 1.96

Memorandum presenting an investigation of a half-delta wing-tip control on a semispan 60 degree delta-wing-fuselage combination conducted in the 9- by 12-inch supersonic blowdown tunnel. Control-surface hinge moments and bending moments, as well as the characteristics of the complete wing-fuselage combination, were obtained over a large range of control deflection and angle of attack at specified Mach and Reynolds numbers. Results regarding the control bending-moment and hinge-moment characteristics, control effectiveness characteristics, and effect of fence on wing characteristics are provided.
Date: October 14, 1952
Creator: Guy, Lawrence D.
System: The UNT Digital Library
Investigation at high subsonic speeds of bodies mounted from the wing of an unswept-wing-fuselage model, including measurements of body loads (open access)

Investigation at high subsonic speeds of bodies mounted from the wing of an unswept-wing-fuselage model, including measurements of body loads

Report presenting an investigation with the dual purpose of determining the effect of two bodies in various positions, symmetrically located from the plane of symmetry, on the aerodynamic characteristics of a wing-fuselage model and determining the aerodynamic loads on one of two bodies. Some of the most significant effects were obtained for the direct-mounted tip bodies which gave a large increase in the lift-curve slope of the basic model.
Date: November 14, 1952
Creator: Silvers, H. Norman & King, Thomas J., Jr.
System: The UNT Digital Library
Oxidation-resistance mechanism and other properties of molybdenum disilicide (open access)

Oxidation-resistance mechanism and other properties of molybdenum disilicide

The outstanding oxidation resistance of molybdenum disilicide at 2400 F and above was found to depend on the formation of a protective siliceous coating which a-cristobalie has been identified. Molybdenum disilicide is not inherently resistant to oxidation and in powdered form burns at low temperatures.Melting and casting experiments have demonstrated the decomposition of the material at the melting point. The room-temperature modulus of elasticity has been determined and electric-resistivity data are given to 2000 F.
Date: March 14, 1952
Creator: Maxwell, W. A.
System: The UNT Digital Library
Relations between fuel properties and combustion carbon deposition (open access)

Relations between fuel properties and combustion carbon deposition

Report discussing some methods for predicting the carbon-forming propensity of turbojet-engine fuels from results of simple laboratory tests of the fuels. The prediction of carbon deposition from fuel characteristics including aromatic content, hydrogen-carbon ratio, distillation temperatures, gravity, and aniline point from several empirical laboratory carbon-deposition tests are provided. Results regarding fuel composition and volatility, related fuel properties, empirical laboratory tests, a comparison of methods predicting carbon-deposition characteristics of fuels, and application of fuel quality control methods are provided.
Date: April 14, 1952
Creator: Jonash, Edmund R.; Wear, Jerrold D. & Hibbard, Robert R.
System: The UNT Digital Library
Effects of horizontal-tail position, area, and aspect ratio on low-speed static longitudinal stability and control characteristics of a 60 degrees triangular-wing model having various triangular-all-movable horizontal tails (open access)

Effects of horizontal-tail position, area, and aspect ratio on low-speed static longitudinal stability and control characteristics of a 60 degrees triangular-wing model having various triangular-all-movable horizontal tails

Report presenting a low-speed investigation in the stability tunnel to determine the static longitudinal stability and control characteristics of a 60 degree triangular-wing model with various triangular-all-movable horizontal tails. An all-movable trail of 10 percent of the wing area and aspect ratio 2.31 was investigated in 17 tail positions, including positions above, below, and to the rear of the assumed center of gravity.
Date: December 14, 1951
Creator: Jaquet, Byron M.
System: The UNT Digital Library
Analysis of coolant-flow requirements for an improved, internal-strut-supported, air-cooled turbine-rotor blade (open access)

Analysis of coolant-flow requirements for an improved, internal-strut-supported, air-cooled turbine-rotor blade

From Introduction: "The purpose of this report is to present the results of the investigation, to compare the coolant-flow requirements of the two configurations, and to show what advantages an air-cooled internal-strut-supported blade may have over an equivalent shell-supported air-cooled blade."
Date: February 14, 1952
Creator: Schramm, Wilson B. & Nachtigall, Alfred J.
System: The UNT Digital Library
Investigations of air-cooled turbine rotors for turbojet engines 2: mechanical design, stress analysis, and burst test of modified J33 split-disk rotor (open access)

Investigations of air-cooled turbine rotors for turbojet engines 2: mechanical design, stress analysis, and burst test of modified J33 split-disk rotor

A full-scale J33 air-cooled split turbine rotor was designed and spin-pit tested to destruction. Stress analysis and spin-pit results indicated that the rotor in a J33 turbojet engine, however, showed that the rear disk of the rotor operated at temperatures substantially higher than the forward disk. An extension of the stress analysis to include the temperature difference between the two disks indicated that engine modifications are required to permit operation of the two disks at more nearly the same temperature level.
Date: January 14, 1952
Creator: Kemp, Richard H. & Moseson, Merland L.
System: The UNT Digital Library