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Investigation at high subsonic speeds of the static lateral and directional stability and tail-loads characteristics of a model having a highly tapered swept wing of aspect ratio 3 and two horizontal-tail positions

Description: Report presenting an investigation made in the 7- by 10-foot tunnel of the static lateral and directional stability and some tail-load characteristics of a model with a highly tapered swept wing and two horizontal-tail positions. Testing were made with the horizontal tail located at the tip of the swept vertical tail and with the horizontal tail located in the wing-chord plane extended. Results regarding static lateral and directional stability and vertical-tail loads are provided.
Date: September 11, 1956
Creator: Few, Albert G., Jr.
Partner: UNT Libraries Government Documents Department

Investigation at transonic speeds of aerodynamic characteristics of a semielliptical air inlet in the root of a 45 degree sweptback wing

Description: Report presenting an investigation in the transonic blowdown tunnel at a range of Mach numbers to determine the increments in lift, drag, and pitching moments due to the installation of a semielliptical-shaped air inlet in the root of a 45 degree sweptback wing and to study the internal flow characteristics of the inlet. Results regarding the internal pressure measurements, effect of inlet installation on external aerodynamic characteristics, effect of boundary-layer removal on internal pressure recovery, and inlet performance are provided.
Date: December 11, 1953
Creator: Howell, Robert R. & Trescot, Charles D., Jr.
Partner: UNT Libraries Government Documents Department

Performance evaluation of reduced-chord rotor blading as applied to J73 two-stage turbine 2: over-all performance at inlet conditions of 35 inches of mercury absolute and 700 degrees R

Description: Report presenting an investigation to determine the feasibility of utilizing a reduced-chord rotor blading on the two-stage turbine of the J73 turbojet engine in order to reduce the weight. The turbine was operated as a component over a range of speeds and overall pressure ratios at turbine-inlet conditions corresponding to 35 inches of mercury absolute and 700 degrees R. Results regarding the overall performance, performance map, and peak efficiency are provided.
Date: July 11, 1957
Creator: Schum, Harold J.; Rebeske, John J., Jr. & Forrette, Robert E.
Partner: UNT Libraries Government Documents Department

Performance evaluation of reduced-chord rotor blading as applied to J73 two-stage turbine 1: over-all performance with standard rotor blading at inlet conditions of 35 inches of mercury absolute and 700 degrees R

Description: Report presenting an investigation conducted to determine the overall performance of the J73 two-stage turbine with a standard rotor-blade configuration. The turbine operated with a maximum brake internal efficiency between 0.91 and 0.92 at an overall pressure ratio of about 3.4 and 120 percent equivalent design rotor speed. Results regarding the overall performance, variation of equivalent weight flow with overall pressure ratio, and effect of limiting blade loading are provided.
Date: July 11, 1957
Creator: Berkey, William E.; Rebeske, John J., Jr. & Forrette, Robert E.
Partner: UNT Libraries Government Documents Department

A specially constructed metallograph for use at elevated temperatures

Description: "A metallographic microscope was developed with provision for heating a specimen to 1800 F in protective atmospheres, that is, vacuum or gas. A special objective was constructed of reflecting elements with an unusually long working distance (7/16 in.) and a high numerical aperture (0.5). Changes in specimen microstructure were observed and recorded on 35-millimeter motion-picture film. The resulting pictures were projected as motion pictures and individual frames were cut and enlargements made for close observation" (p. 1).
Date: September 11, 1951
Creator: Jenkins, Joe E.; Buchele, Donald R. & Long, Roger A.
Partner: UNT Libraries Government Documents Department

Wind-tunnel oscillation tests of the Bendix-Friez aerovane anemometer

Description: Report presenting a Bendix-Friez Aerovane Anenometer oscillated in the streamwise direction at several frequencies for each of several low wind-tunnel airspeeds. Records of the displacement of the anenometer and velocity indicated by the instrument during oscillation are provided. The over-registration of this anenometer was found to be much smaller than predicted by theory.
Date: August 11, 1953
Creator: Fisher, Lewis R.
Partner: UNT Libraries Government Documents Department

Aerodynamic study of a wing-fuselage combination employing a wing swept back 63 degrees: Subsonic Mach and Reynolds number effects on the characteristics of the wing and on the effectiveness of an elevon

Description: Report presenting a wind-tunnel investigation of a semispan model of a wing swept back 63 degrees with an aspect ratio of 3.5 and a taper ratio of 0.25. The tests were conducted to evaluate the effects of Reynolds and Mach number on the aerodynamic characteristics of the wing. Results regarding the characteristics of the wing with the elevon undeflected, effectiveness of the elevon, effects of roughness strips, and effect of model deflection under varying loads are provided.
Date: October 11, 1948
Creator: Reynolds, Robert M. & Smith, Donald W.
Partner: UNT Libraries Government Documents Department

Effect of inlet-duct length in uniform-flow field on turbojet-engine operation

Description: Report presenting a high-pressure-ratio axial-flow turbojet engine in the altitude wind tunnel to determine the effect of inlet-duct length on engine operation. Data were obtained with a short bellmouth inlet and a 20-foot duct section of uniform diameter between the inlet and compressor. Results regarding the steady-state characteristics, acceleration characteristics, compressor stall limits, and surge characteristics are provided.
Date: April 11, 1956
Creator: Lubick, Robert J.; Chelko, Louis J. & Wallner, Lewis E.
Partner: UNT Libraries Government Documents Department

Effects of Secondary-Air Flow on Annular Base Force of a Supersonic Airplane

Description: Memorandum presenting an investigation of the effect of base bleed on the base force of a supersonic-interceptor model in the 8- by 6-foot supersonic wind tunnel. Two groups of fixed-geometry nozzles and shroud combinations simulating double-iris-type configurations were evaluated over a range of secondary to primary exit-diameter ratios.
Date: October 11, 1954
Creator: Vargo, Donald J.
Partner: UNT Libraries Government Documents Department

Investigation of a translating-cone inlet at Mach numbers from 1.5 to 2.0

Description: Report presenting an investigation in the 8- by 6-foot supersonic wind tunnel to evaluate the performance of a translating-cone inlet operated over a range of Mach numbers and angles of attack. The effects of spike projection and internal flow area variation on pressure recovery, external drag, and corrected air-flow variation were determined.
Date: May 11, 1954
Creator: Sterbentz, William H. & Leissler, L. Abbott
Partner: UNT Libraries Government Documents Department

Low-speed longitudinal aerodynamic characteristics of a twisted and cambered wing of 45 degree sweepback and aspect ratio 8 with and without high-lift and stall-control devices and a fuselage at Reynolds numbers from 1.5 x 10(exp 6) to 4.8 x 10(exp 6

Description: Report presenting a low-speed investigation of the static longitudinal aerodynamic characteristics of a twisted and cambered wing with 45 degrees of sweepback and an aspect ratio of 8.0 in the 19-foot pressure tunnel. Testing included the effects of leading- and trailing-edge flaps, flow control fences, and a fuselage. Report presenting longitudinal stability characteristics, lift characteristics, drag characteristics, fuselage effects, Reynolds number effects, effect of wing roughness are provided.
Date: June 11, 1952
Creator: Salmi, Reino J.
Partner: UNT Libraries Government Documents Department

Low-velocity turning as a means of minimizing boundary-layer accumulations resulting from secondary flows within turbine stators

Description: A study of a series of three single-passage nozzles, designed to turn the flow at different velocity levels but to identical outlet conditions, in order to determine whether secondary-flow accumulations of boundary-layer fluids within nozzles could be minimized by use of low-velocity turning. Results indicated that the type of turning with subsequent acceleration is highly effective in minimizing secondary-flow accumulations at the corner where the suction surface joins the end walls.
Date: May 11, 1954
Creator: Stewart, Warner L. & Wong, Robert Y.
Partner: UNT Libraries Government Documents Department

Performance characteristics of cylindrical target-type thrust reversers

Description: From tests on cylindrical target-type thrust reversers, it was found that the reverser frontal area, lip angle, end-plate angle, and end-plate depth had important effects on reverse-thrust performance. Frontal area, reverser depth, lip angle, and end-plate angele had important effects on the spacing required for unrestricted nozzle flow. For reverse-thrust ratios greater than 64 percent, the reversed flow attached to the 7 degree cowl in quiescent air. Swept-type cylindrical reversers were generally unstable. The thrust-modulation characteristics of a cylindrical target-type thrust reverser were found to be satisfactory.
Date: January 11, 1956
Creator: Steffen, Fred W. & McArdle, Jack G.
Partner: UNT Libraries Government Documents Department

Experimental investigation of a two-dimensional split-wing ram-jet inlet at Mach number of 3.85

Description: Performance characteristics of a two-dimensional isentropic diffuser have been experimentally determined at a Mach number of 3.85. At zero angle of attack, a maximum total-pressure recovery of 0.41 was obtained with a supercritical mass-flow ratio of 0.95. As a consequence of the twin-duct arrangement of the diffuser, a large discontinuity in pressure recovery and mass flow with a characteristic hysteresis was encountered between critical and subcritical operation. An asymmetric shock pattern with large-scale separation and flow reversal in one of the passages occurred at reduced mass flows. Pressure and force data presented for an angle-of-attack range from zero to 4 degrees.
Date: August 11, 1952
Creator: Connors, James F. & Woollett, Richard R.
Partner: UNT Libraries Government Documents Department

Flight measurements of section efficiency, thrust, and power of a supersonic-type propeller at Mach numbers to 0.9

Description: Report discussing testing on a supersonic-type propeller designed for a forward Mach number of 0.95, advance ratio of 2.2, and power coefficient of 0.26. Thrust distributions were found to be smooth and uniform over a range of Mach numbers, indicating efficient operation.
Date: January 11, 1956
Creator: Hammack, Jerome B. & O'Bryan, Thomas C.
Partner: UNT Libraries Government Documents Department

Force characteristics in the submerged and planing condition of a 1/5.78-scale model of a hydro-ski-wheel combination for the Grumman JRF-5 airplane

Description: From Summary: "Force characteristics determined from tank tests of a 1/5.78-scale model of a hydro-ski-wheel combination for the Grumman JRF-5 airplane are presented. The model was tested in both the submerged and planing conditions over a range of trim, speed, and load sufficiently large to represent the most probable full-size conditions."
Date: July 11, 1952
Creator: Land, Norman S. & Pelz, Charles A.
Partner: UNT Libraries Government Documents Department

An investigation of the low-speed longitudinal stability characteristics of a swept-wing airplane model with two modifications to the wing-root plan form

Description: Report presenting a wind-tunnel investigation to determine the effects of two wing-root leading-edge plan-form modifications, including a notched leading-edge fillet and a rounded leading-edge fillet, on the low-speed longitudinal stability characteristics of an airplane model with a 50.7 degree sweptback wing. Results regarding stability at zero lift, variation of stability with lift coefficient, and lift and drag characteristics are provided.
Date: July 11, 1952
Creator: Kemp, William B., Jr.
Partner: UNT Libraries Government Documents Department

Comparison of two methods of modulating the throat area of convergent plug nozzles

Description: Report presenting an investigation to determine the effect on performance of two methods of throat-area modulation of two convergent plug nozzles. Data were obtained over a range of pressure ratios. Results regarding the performance of the translatable outer-shell-type plug nozzle, performance of the iris-outer-shell-type plug nozzles, sensitivity to throat-area variation, and air-flow parameter are provided.
Date: May 11, 1955
Creator: Krull, H. George & Beale, William T.
Partner: UNT Libraries Government Documents Department

Design and investigation of a transonic axial-flow compressor rotor with an inlet hub-tip radius ratio of essentially zero

Description: Report presenting an investigation of an axial-flow compressor rotor with an inlet hub-tip radius ratio of basically zero. Results regarding the radial distribution of total-pressure ratio and efficiency, measured pressure ratio at design speed, weight flow, and low-speed cascade data are provided.
Date: March 11, 1957
Creator: Westphal, Willard R. & Maynard, John W., Jr.
Partner: UNT Libraries Government Documents Department

Design and performance of a 1400-foot-per-second-tip-speed supersonic compressor rotor

Description: Report presenting performance testing of a supersonic compressor designed for a tip speed of 1400 feet per second, a pressure ratio of 2.0, and a corrected weight flow of 30.5 pounds per second. The overall performance results of the rotor alone at design speed gave a pressure ratio of 2.17, an adiabatic efficiency of 89 percent, and a weight flow of 28 pounds per second. A comparison with the predicted design results is provided.
Date: April 11, 1955
Creator: Klapproth, John F.; Jacklitch, John J., Jr. & Tysl, Edward R.
Partner: UNT Libraries Government Documents Department

An experimental investigation of hollow turbine blades for expandable jet engines

Description: From Summary: "An experimental investigation was made to determine the feasibility of using hollow turbine blades in engines designed for short service life. Airfoils were fabricated from sheet material and techniques of welding and brazing attachment were investigated. The airfoils were not intended to be cooled. A principal objective was the reduction of strategic material requirements primarily as a function of direct weight reduction."
Date: March 11, 1954
Creator: Morgan, W. C. & Morse, C. R.
Partner: UNT Libraries Government Documents Department

Investigation at Mach number 1.91 of spreading characteristics of jet expanding from choked nozzles

Description: It is demonstrated that the temperature profiles of jets expanding into a supersonic stream are considerably smaller than the temperature profiles of jets expanding into quiescent air. The effect on the wake of varying afterbody geometry is shown to be small. The gross spreading characteristics of jets expanding from convergent and convergent-divergent nozzles in the base of a body of revolution with various boattail configurations at a Mach number of 1.91 are presented.
Date: January 11, 1952
Creator: Rousso, Morris D. & Baughman, L. Eugene
Partner: UNT Libraries Government Documents Department

Thrust and drag characteristics of a convergent-divergent nozzle with various exhaust jet temperatures

Description: From Summary: "An investigation was conducted in the 8-by-6 foot supersonic wind tunnel on the effect of exhaust-gas temperatures on the external and internal characteristics of a convergent-divergent nozzle having an area expansion ratio of 1.83. Data were obtained over a pressure-ratio range from 1 to 20 at free-stream Mach numbers of 1.6 and 2.0 for exhaust temperatures of 860 degrees, 1650 degrees, and 2000 degrees R. Results of this investigation indicated that generally both the internal and external performance characteristics were only slightly affected by a large change in jet temperature. The small differences in performance which did occur were predicted satisfactorily from theoretical considerations."
Date: March 11, 1954
Creator: Hearth, Donald P. & Wilcox, Fred A.
Partner: UNT Libraries Government Documents Department

Analysis of factors affecting selection and design of air-cooled single-stage turbines for turbojet engines 4: coolant-flow requirements and performance of engines using air-cooled corrugated-insert blades

Description: Report presenting an investigation of the estimated minimum cooling requirements and related performance of turbojet engines equipped with high-performance single-stage turbines with air-cooled corrugated-insert blades over a range of turbine-inlet temperature, tip speed, and hub-tip radius ratio for Mach number 2 at 50,000 feet. The effects of stress-ratio factor, flight Mach number, altitude, turbine rotor impeller efficiency, and outside heat-transfer coefficient on cooling requirements were also investigated.
Date: May 11, 1955
Creator: Slone, Henry O. & Hubbartt, James E.
Partner: UNT Libraries Government Documents Department