The effect of high solidity on propeller characteristics at high forward speeds from wind-tunnel tests of the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 two-blade propellers (open access)

The effect of high solidity on propeller characteristics at high forward speeds from wind-tunnel tests of the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 two-blade propellers

From Summary: "Tests of two-blade propellers having the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 blade designs (blade activity factors of 179 and 263, respectively) have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 70 degrees for free-stream Mach numbers from 0.165 to 0.725 to determine the effects of high solidity and compressibility on propeller characteristics. The tests are part of a general investigation of propellers at high forward speeds. Results previously reported for similar tests of two-blade propellers having the NACA 4-308-03 and NACA 4-308-045 blade designs (blade activity factors of 87 and 133, respectively) are included for comparison. The results showed that the 0.06- and 0.09-solidity blades, although producing efficiencies of the order of 90 percent, were less efficient than blades of conventional solidity."
Date: February 27, 1947
Creator: Delano, James B.
System: The UNT Digital Library
Lateral Stability Characteristics of a 1/8.33-Scale Powered Model of the Republic XF-12 Airplane (open access)

Lateral Stability Characteristics of a 1/8.33-Scale Powered Model of the Republic XF-12 Airplane

"The XF-12 airplane is a high-performance photo-reconnaissance aircraft designed for the Army Air Forces by the Republic Aviation Corporation. An investigation of a 1/8.33 - scale powered model was made in the Langley l9-foot pressure tunnel to obtain information relative to the aerodynamic design of the airplane. The model was tested with and without the original vertical tail. and with two revised tails. For the revised tail no. 1, the span of the original vertical .tail was increased about 15 percent and the portion of the vertical tail between the stabilizer and fuselage behind the rudder hinge line was allowed to deflect simultaneously with the main rudder" (p. 1).
Date: February 27, 1947
Creator: Pepper, Edward & Foster, Gerald V.
System: The UNT Digital Library
High-speed aerodynamic characteristics of horn and overhang balances on a full-scale elevator (open access)

High-speed aerodynamic characteristics of horn and overhang balances on a full-scale elevator

Report presenting high-speed wind tunnel testing of horn- and overhang-balance elevators on a full-scale, semispan, horizontal tail. The effects of unshielding the horn and unsealing the overhang were investigated. Results regarding aerodynamic characteristics, distortions of the tail, and critical Mach numbers are provided.
Date: February 27, 1948
Creator: Cleary, Joseph W. & Krumm, Walter J.
System: The UNT Digital Library
Stall Characteristics Obtained from Flight 10 of Northrop X-4 No. 2 Airplane (USAF No. 46-677) (open access)

Stall Characteristics Obtained from Flight 10 of Northrop X-4 No. 2 Airplane (USAF No. 46-677)

NACA instrumentation has been installed in the X-4 airplanes to obtain stability and control data during the acceptance tests conducted by the Northrop Aircraft Corporation. This report presents data obtained on the stalling characteristics of the airplane in the clean and gear- down configurations. The center of gravity was located at approximately 18 percent of the mean aerodynamic chord during the tests. The results indicated that the airplane was not completely stalled when stall was gradually approached during nominally U accelerated flight but that it was completely stalled during a more abruptly approached stall in accelerated flight. The stall in accelerated flight was relatively mild, and this was attributed to the nature of the variation of lift with angle of attack for the 001-614 airfoil section, the plan form of the wing, and to the fact that the initial sideslip at the stall produced (as shown by wind-tunnel tests of a model of the airplane) a more symmetrical stall pattern.
Date: February 27, 1950
Creator: Sadoff, Melvin & Sisk, Thomas R.
System: The UNT Digital Library
Turbojet-engine evaluation of AISI 321 and AISI 347 stainless steels as nozzle-blade materials (open access)

Turbojet-engine evaluation of AISI 321 and AISI 347 stainless steels as nozzle-blade materials

Report presenting an investigation to evaluate the engine service performance of nozzle-diaphragm blades of AISI 321 and AISI 347 stainless steels. Data were obtained from three nozzle diaphragms alternately bladed with each of the two materials. Results regarding a visual inspection, a metallurgical examination, the mechanism of cracking, and the classification of failures are provided.
Date: February 27, 1950
Creator: Garrett, Floyd B. & Yaker, Charles
System: The UNT Digital Library
Comparison of Turbojet-Engine Altitude Performance Characteristics and Ignition Limits With MIL-F-5624A Fuel, Grades JP-3 and JP-4 (open access)

Comparison of Turbojet-Engine Altitude Performance Characteristics and Ignition Limits With MIL-F-5624A Fuel, Grades JP-3 and JP-4

The performance of MIL-F-5624A fuels, grades JP-3 and JP-4, was investigated in an axial-flow turbojet engine over a range of altitude conditions of 10,000 to 55,000 feet. Examination of the fuel flow, combustion efficiency, and net thrust specific fuel consumption showed the grade JP-4 fuel to be slightly inferior to the grade JP-3 fuel, although the altitude ignition limits were essentially equal for the two fuels over a range of flight Mach numbers and fuel-inlet temperatures.
Date: February 27, 1952
Creator: Braithwaite, Willis M. & Renas, Paul E.
System: The UNT Digital Library
Pressure Recovery, Drag, and Subcritical Stability Characteristics of Conical Supersonic Diffusers With Boundary-Layer Removal (open access)

Pressure Recovery, Drag, and Subcritical Stability Characteristics of Conical Supersonic Diffusers With Boundary-Layer Removal

A study of two 20 degrees half-angle, low mass-flow ratio conical supersonic inlets with cone boundary-layer bleed was made on a 16-inch ram-jet engine in the Lewis 8- by 6-foot supersonic wind tunnel. A greater stable subcritical range of operation was obtained with the bleed inlets than with the corresponding inlet without boundary-layer bleed. The drag added by the bleed system was small.
Date: February 27, 1952
Creator: Obery, Leonard J.; Englert, Gerald W. & Nussdorfer, Theodore J.
System: The UNT Digital Library
Pressure Recovery, Drag, and Subcritical Stability Characteristics of Three Conical Supersonic Diffusers at Stream Mach Numbers From 1.7 to 2.0 (open access)

Pressure Recovery, Drag, and Subcritical Stability Characteristics of Three Conical Supersonic Diffusers at Stream Mach Numbers From 1.7 to 2.0

A study of a 20 degree and a 25 degree half-angle high mass-flow ratio conical supersonic inlet was made on a 16-inch ram jet in the 8- by 6-foot supersonic tunnel. A greater range of stable subcritical operation was obtained with the low mass-flow ratio inlets; a greater range was obtained with the 25 degree than with the 20 degree half-angle low mass-flow ratio inlet. The high mass-flow ratio inlet had the least drag.
Date: February 27, 1952
Creator: Nussdorfer, Theodore J.; Obery, Leonard J. & Englert, Gerald W.
System: The UNT Digital Library
Transonic Characteristics of a 45 Degree Sweptback Wing-Fuselage Combination: Effect of Longitudinal Wing Position and Division of Wing and Fuselage Forces and Moments (open access)

Transonic Characteristics of a 45 Degree Sweptback Wing-Fuselage Combination: Effect of Longitudinal Wing Position and Division of Wing and Fuselage Forces and Moments

Report presenting an investigation on a body of revolution with a sweptback wing with a 0.25-mean-aerodynamic-chord point at the maximum body diameter and 1.2 mean aerodynamic chords behind the maximum diameter. The fuselage had a fineness ratio of 10, a 45 degree swept wing with an aspect ratio of 4.0, a taper ratio of 0.6, and NACA 65A006 airfoil sections parallel to the plane of symmetry. Lift, drag, pitching moments, and angles of attack were measured at a range of Mach numbers.
Date: February 27, 1953
Creator: Hallissy, Joseph M. & Bowman, Donald R.
System: The UNT Digital Library
Aerodynamic principles for the design of jet-engine induction systems (open access)

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."
Date: February 27, 1956
Creator: Davis, Wallace F. & Scherrer, Richard
System: The UNT Digital Library
Aerodynamic Principles for the Design of Jet-Engine Induction Systems (open access)

Aerodynamic Principles for the Design of Jet-Engine Induction Systems

Jet engine induction systems investigations and relationship of air inlets, drag, airframe, pressure recovery, flow and interferences.
Date: February 27, 1956
Creator: Davis, Wallace F. & Scherrer, Richard
System: The UNT Digital Library
Tabulated pressure data for several flap-type trailing edge controls on a trapezoidal wing at Mach numbers of 1.61 and 2.01 (open access)

Tabulated pressure data for several flap-type trailing edge controls on a trapezoidal wing at Mach numbers of 1.61 and 2.01

Report presenting an investigation at two Mach numbers for a range of Reynolds numbers to determine the pressure distributions at several spanwise stations for a series of 25.4-percent-chord trailing-edge controls on a trapezoidal wing with a 23 degree sweptback leading edge, aspect ratio of 3.1, and taper ratio of 0.4. The report contains the tabulated pressure data for the complete range of test variables.
Date: February 27, 1956
Creator: Lord, Douglas R. & Czarnecki, K. R.
System: The UNT Digital Library
Comparison of Combustion Reactivity of Ethyldecaborane Fuels With Typical Hydrocarbon Fuels on Basis of Spray Flammability Limits of Fuel-Rich Mists and Calculated Lean-Limit Flame Temperatures for Fuel Vapor-Air Systems (open access)

Comparison of Combustion Reactivity of Ethyldecaborane Fuels With Typical Hydrocarbon Fuels on Basis of Spray Flammability Limits of Fuel-Rich Mists and Calculated Lean-Limit Flame Temperatures for Fuel Vapor-Air Systems

From Summary: "The spray flammability limits of various high-energy fuels and hydrocarbon fuels were determined experimentally in an apparatus which measured the minimum percent of oxygen by volume that would permit the ignition of a particular fuel. The fluids investigated were ethyldecaboranes, aliphatic hydrocarbons, olefins, aromatic hydrocarbons, and esters."
Date: February 27, 1957
Creator: Wise, Paul H. & Lipschitz, Abraham
System: The UNT Digital Library
Design and test of mixed-flow impellers 8: comparison of experimental results for three impellers with shroud redesigned by rapid approximate method (open access)

Design and test of mixed-flow impellers 8: comparison of experimental results for three impellers with shroud redesigned by rapid approximate method

Report presenting a comparison of three centrifugal impellers with parabolic, circular, and skewed-parabolic blading that were modified using a recently developed design procedure to reduce velocity gradients along the hub from inlet to outlet. All of the original dimensions except for the shroud contours were retained. Results regarding a comparison of the original and modified parabolic-bladed, circular-bladed, and skewed-parabolic bladed impeller are provided.
Date: February 27, 1957
Creator: Osborn, Walter M.; Smith, Kenneth J. & Hamrick, Joseph T.
System: The UNT Digital Library
Experimental investigation of ejector-nozzle metal temperatures (open access)

Experimental investigation of ejector-nozzle metal temperatures

Metal temperatures were obtained on a full-scale ejector nozzle installed on an afterburner operating at exhaust-gas temperatures up to 3450 degrees R. A favorable afterburner-outlet temperature profile helped keep the primary-jet nozzle components cool. The ejector shroud temperatures were much more sensitive to secondary airflow than were temperatures on the primary-jet nozzle.
Date: February 27, 1957
Creator: Shillito, Thomas B. & Koffel, William K.
System: The UNT Digital Library
Preliminary Investigation of the Combustion of Pentaborane and Diborane in a Turbojet Combustor at Simulated Altitude Conditions (open access)

Preliminary Investigation of the Combustion of Pentaborane and Diborane in a Turbojet Combustor at Simulated Altitude Conditions

Report presenting an investigation to determine the combustion characteristics of pentaborane and diborane in a turbojet combustor. Four different test conditions were explored, which varied in inlet total pressure, temperature, and simulated flight conditions. Results regarding the combustor itself and performance of diborane fuel at high altitude are provided.
Date: February 27, 1957
Creator: Gibbs, J. B.; Kaufman, W. B. & Branstetter, J. R.
System: The UNT Digital Library
A summary of the longitudinal and lateral stability and control characteristics obtained from rocket-model tests of a swept-wing fighter-type airplane at Mach numbers from 0.5 to 1.9 (open access)

A summary of the longitudinal and lateral stability and control characteristics obtained from rocket-model tests of a swept-wing fighter-type airplane at Mach numbers from 0.5 to 1.9

Report presenting a flight investigation of a swept-wing fighter-type airplane to determine drag coefficients, longitudinal and lateral stability derivatives, effects of aeroelasticity on rolling effectiveness, and the effect of the engine jet exhaust on the trim characteristics over the range of Mach numbers.
Date: February 27, 1957
Creator: Mitcham, Grady L.
System: The UNT Digital Library