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Wind-tunnel measurements of the dynamic cross derivative (rolling moment due to yawing velocity and to acceleration in sideslip) of the Douglas D-558-II airplane and its components at supersonic speeds including description of the technique

Description: Report presenting a technique and the results obtained of wind-tunnel forced-oscillation tests on a model of the Douglas D-558-II airplane which was instrumented to obtain the dynamic cross derivative and static derivative. Tests were conducted for a range of Mach numbers and angles of attack. Results regarding sample calculations of the period and damping of the full-scale airplane are provided despite not being conclusive due to the inadequate number of flight conditions investigated.
Date: November 3, 1955
Creator: Boatright, William B.

Wind-tunnel measurements of wing buffeting on 1/16-scale model of Douglas D-558-II research airplane

Description: Report presenting exploratory measurements of the fluctuations of wing bending moment during normal performance and wind-tunnel testing of a model of the Douglas D-558-II from Mach numbers 0.60 to 0.96. The effects of leading-edge chord-extensions and pylon-mounted underwing external stores were investigated. Results regarding the general nature of buffeting measurements, frequency distribution of buffeting response, interpretation of model buffeting measurements, and effects of changes in model configuration are provided.
Date: September 24, 1956
Creator: Kemp, William B., Jr. & King, Thomas J., Jr.

Wind-Tunnel Tests of a 0.16-Scale Model of the Douglas MX-656 Airplane at High Subsonic Speeds, 1, Stability and Control Characteristics

Description: Wind tunnel tests of the 0.16-scale Douglas MX-656 model were made at low and high subsonic Mach numbers to investigate the static longitudinal- and lateral stability characteristics. The tests shows that undesirable changes in longitudinal stability at the stall were apparently caused by an altered downwash pattern at the tail. The jettisonable nose fins were highly destabilizing. Compressibility effects for the test Mach numbers were not detrimental to the longitudinal- or lateral-stability characteristics.
Date: April 26, 1949
Creator: Hamilton, William T. & Cleary, Joseph W.

Wind-Tunnel Tests of a 0.16-Scale Model of the Douglas MX-656 Airplane at High Subsonic Speeds. 2 - Wing and Fuselage Pressure Distribution

Description: From Summary: "Measurements of wing and fuselage pressure distributions were made at low and high subsonic Much numbers on a 0.16-scale model of the projected MX-656 research airplane. The MX-656 is a supersonic design utilizing a low-aspect-ratio wing and tail. Pressure-distribution measurements indicated that, although the critical Mach number of the wing was approximately 0.81 at 0 degree angle of attack, compressibility effects were of little significance below a Mach number of at least 0.90. The principal effect of compressibility was an increase in the pressure gradient over the after 30 percent of the wing chord, causing a tendency for the flow to separate."
Date: August 22, 1949
Creator: Cleary, Joseph W. & Mellenthin, Jack A.

Wind-tunnel tests of a 0.16-scale model of the X-3 airplane at high subsonic speeds : additional stability and control characteristics and the aerodynamic effects of external stores and ram jets

Description: Report presenting additional wind-tunnel tests of a model of the X-3 airplane at low and high subsonic numbers to investigate the lateral and longitudinal-stability and control characteristics. Results regarding the aerodynamic characteristics in pitch and aerodynamic characteristics in yaw are provided.
Date: June 13, 1950
Creator: Cleary, Joseph W. & Mellenthin, Jack A.

Wind-tunnel tests of a 0.16-scale model of the X-3 airplane at high subsonic speeds: stability and control characteristics

Description: Report presenting static lateral- and longitudinal-stability tests of a scale model of a projected, low-aspect-ratio, supersonic airplane at low and high subsonic Mach numbers. The wing was equipped with leading-edge flaps and had a modified double-wedge airfoil with sharp leading and trailing edges. Results regarding lift characteristics, static longitudinal stability and control, lateral and directional stability, drag characteristics, and wing and fuselage tuft studies are provided.
Date: April 21, 1950
Creator: Hamilton, William T. & Cleary, Joseph W.

Wind-tunnel tests of a 0.16-scale model of the X-3 airplane at high subsonic speeds: wing and fuselage pressure distribution

Description: Report presenting measurements of wing and fuselage pressure distributions made at low and high subsonic Mach numbers on a scale model of the projected X-3 research airplane. Tests were conducted in pitch and yaw and included measurements of the total pressure in the fuselage boundary layer at the location of the left boundary-layer bleed scoop.
Date: June 22, 1950
Creator: Cleary, Joseph W. & Mellenthin, Jack A.

Wind-Tunnel Tests of a 0.182-Scale Model of an F4U-1 Airplane with External Stores

Description: Tests were made in the Langley 7- by 10-foot tunnel on a 0.182-scale model of an F4U-1 airplane with external stores. This paper is concerned mainly with presenting the data obtained in this investigation and with a comparison of some of these data with flight-test results determining the feasibility of estimating flight buffet Mach number from tunnel data. The results of this investigation indicate that the incremental drag coefficient due to external stores may be used to estimate the maximum Mach number that the F4U-1 airplane may reach in flight when it is equipped with external stores. This estimation is conservative for the five configurations investigated by mounts varying from 0 to 10 percent of the flight limit Mach number. The free-stream tunnel Mach number corresponding to sonic flow over the lower surface of the wing in the region of the store is a good indication of the lower limit of buffet in flight of the F4U-1 airplane when equipped with external stores. The fluctuations of total pressure over the horizontal tail are not sufficiently large (maximum of 1 percent q(sub o) to cause buffeting of the airplane.
Date: June 5, 1947
Creator: Silvers, H. Norman & Spreemann, Kenneth P.

Wind-Tunnel Tests of a 1/4-Scale Model of the Naval Aircraft Factory Float-Wing Convoy Interceptor, TED No. NACA 2314

Description: A 1/4 - scale model of the Naval Aircraft Factory float-wing convoy interceptor was tested in the Langley 7-by 10-foot tunnel to determine the longitudinal and lateral stability characteristics. The model was tested in the presence of a ground board to determine the effect of simulating the ground on the longitudinal characteristics.
Date: January 16, 1947
Creator: Wells, Evalyn G. & McKinney, Elizabeth G.

Wind-Tunnel Tests of a 1/8-Scale Powered Model of the XTB3F-1 Airplane, TED No. NACA 2382

Description: A 1/8 scale model of the Grumman XTB3F-1 airplane was tested in the Langley 7- by 10-foot tunnel to determine the stability and control characteristics and to provide data for estimating the airplane handling qualities. The report includes longitudinal and lateral stability and control characteristics of the complete model, the characteristics of the isolated horizontal tail, the effects of various flow conditions through the jet duct, tests with external stores attached to the underside of the wing, ana tests simulating landing and take-off conditions with a ground board. The handling characteristics of the airplane have not been computed but some conclusions were indicated by the data. An improvement in the longitudinal stability was obtained by tilting the thrust line down. It is shown that if the wing flap is spring loaded so that the flap deflection varies with airspeed, the airplanes will be less stable than with the flap retracted or fully deflected. An increase in size of the vertical tail and of the dorsal fin gave more desirable yawing-moment characteristics than the original vertical tail and dorsal fin. Preventing air flow through the jet duct system or simulating jet operation with unheated air produced only small changes in the model characteristics. The external stores on the underside of the wing had only small effects on the model characteristics. After completion of the investigation, the model was returned to the contractor for modifications indicated by the test results.
Date: August 1947
Creator: McKee, John W. & Vogler, Raymond D.

Wind-tunnel tests of a 1/12-scale model of the X-3 airplane at subsonic and supersonic speeds.

Description: Report presenting the static longitudinal-, lateral-, and directional-stability and control characteristics of a model of the Douglas X-3 airplane at subsonic and supersonic Mach numbers. The model was equipped with an all-movable horizontal tail, an aileron on the left wing, and a rudder on the vertical-tail surface.
Date: September 14, 1951
Creator: Olson, Robert N. & Chubb, Robert S.

Wind-tunnel tests of a model of a wingless fin-controlled missile to obtain static stability and control characteristics through a range of Mach numbers from 0.5 to 0.88

Description: From Summary: "An investigation at medium to high subsonic speeds has been conducted in the Langley low-turbulence pressure tunnel to determine the static stability and control characteristics and to measure the fin normal forces and moments for a model of a wingless fin-controlled missile. With the horizontal-fin deflection limited to a maximum of 6 degrees, longitudinally stable and trimmed flight could not be maintained beyond an angle of attack of 17 degrees for a Mach number of 0.88 and beyond 20 degrees for a Mach number of 0.50 for any center-of-gravity location without the use of some auxiliary stability or control device such as jet vanes."
Date: April 12, 1954
Creator: Burrows, Dale L. & Newman, Ernest E.

Wind-Tunnel Tests of a Modified Koppers Aeromatic Impeller-Generator Combination, TED No. NACA ARR 2901

Description: From Summary: "An investigation was conducted in the 6- by 6-foot test section of the Langley stability tunnel on a modified Koppers Aeromatic wind-driven impeller-generator combination. This investigation consisted of a few fixed pitch tests and a series of variable pitch tests. The fixed pitch tests indicated that the impeller should operate between the blade-pitch angles of 20 and 32deg at the specified output of 11.7 kilowatts in order to remain within the specified rotational speed of from 5000 to 8000 rpm for airspeeds of from 130 to 175 miles per hour. The requirement that the impeller maintain rotational speeds of - between 5000 and 8000 rpm as the impeller output varied from 0 to ll.7 kilowatts at airspeeds of from 130 to 175 miles per hour was not met at any time during the variable pitch tests."
Date: December 26, 1946
Creator: Queijo, M. J.

Wind-tunnel tests of a series of practice bombs

Description: Report discussing zero-lift drag data for several bomb configurations at various Mach numbers. Seven configurations were tested with different combinations of interchangeable noses and tail cones with fins, some with different surface conditions. Surface conditions were not found to affect the drag, but the thickness of the tail fins and shape of the noses did change the shape of the drag curve.
Date: October 1, 1957
Creator: Ward, Donald H.

Wind-tunnel tests of a swept-blade propeller and related straight blades having thickness ratios of 5 and 6 percent

Description: Report discussing the aerodynamic characteristics of three sets of blades over as wide a range of operating conditions as possible. One set of blades was conventional, one had blades that embodied sweep, and one was a nonswept set with thinner blade sections. The sweptback blades were found to be generally inferior to the straight blades, but the Mach numbers tested were not high enough to include speeds that might benefit from sweepback.
Date: November 10, 1948
Creator: Gray, W. H.

Wind-tunnel tests of blowing boundary-layer control with jet pressure ratios up to 9.5 on the trailing-edge flaps of a 35 degree sweptback wing airplane

Description: Report presenting a full-scale wind-tunnel investigation to determine whether the effects of blowing high-velocity air over trailing-edge flaps could be adequately correlated by jet momentum over a range of jet velocities. Good correlation of lift with jet momentum was obtained over the range of jet pressure ratios.
Date: October 26, 1956
Creator: Kelly, Mark W. & Tucker, Jeffrey H.

Wind-Tunnel Tests of the 1/25-Scale Powered Model of the Martin JRM-1 Airplane. 4 - Tests with Ground Board and with Modified Wing and Hull - TED No. NACA 232, Part 4, Tests with Ground Board and with Modified Wing and Hull, TED No. NACA 232

Description: From Summary: "Wind-tunnel tests were made of a 1/25 scale model of the Martin JRM-1 airplane to determine: (1) The longitudinal stability and control characteristics of the JRM-1 model near the water and lateral and directional stability characteristics with power while moving on the surface of the water, the latter being useful for the design of tip floats; (2) The stability and stalling characteristics of the wing with a modified airfoil contour; (3) Stability characteristics of a hull of larger design gross weight; The test results indicated that the elevator was powerful enough to trim the original model in a landing configuration at any lift coefficient within the specified range of centers of gravity."
Date: September 4, 1947
Creator: Lockwood, Vernard E. & Smith, Bernard J.

Wind-tunnel tests of the static longitudinal characteristics at low speed of a swept-wing airplane with blowing flaps and leading-edge slats

Description: Report presenting a wind-tunnel investigation of a high-wing airplane with an aspect ratio 6.75 wing with approximately 36 degrees of sweepback to determine the lift effectiveness obtainable with trailing-edge blowing flaps in combination with leading-edge slats. Flap effectiveness and stability were maintained to high angles of attack by control of leading-edge flow separation with slats. An analysis of the take-off performance, landing performance, and comparisons with flight data are provided.
Date: July 5, 1957
Creator: James, Harry A. & Maki, Ralph L.

Wind-tunnel tests of the static longitudinal characteristics at low speed of a swept-wing airplane with slotted flaps, area-suction flaps, and wing leading-edge devices

Description: Report presenting a low-speed wind-tunnel investigation of a high-wing airplane with an aspect ratio of 6.75 and 36 degrees of sweepback on the quarter-chord line in order to determine the lift increments obtainable with area-suction flaps. Comparisons were made to the slotted flaps normally used. Results regarding the flap lift, maximum lift and stability, and boundary-layer control requirements are provided.
Date: April 30, 1957
Creator: Maki, Ralph L. & James, Harry A.

Wind-Tunnel Tests to Determine Aileron Characteristics of the McDonnell XFD-1 Airplane, TED No. NACA 23102

Description: Tests were performed on a partial span of the wing of a McDonnell XFD-1 airplane to determine a combination of sealed internal balance and spring-tab stiffness for the aileron that would give satisfactory stick-force characteristics for the airplane. Two sealed internal balances were tested in combination with spring tabs of various stiffnesses. One of the combinations was tested at several speeds to determine the variation of stick force with speed. Estimates, based on the results of the tests, indicate that for this airplane any reduction of stick force by use of the spring tab reduces the helix angle pb/2V below the required value of 0.09. The estimates show that, of the configurations tested, the most satisfactory combination for obtaining a stick force of 30 pounds at 300 miles per hour indicated airspeed is a 0.48-chord internal balance in combination with a spring-tab stiffness of 500 pounds per inch. With this combination, a wing-tip helix angle of 0.078 is estimated. Stick-force curves for all configurations show a rapid increase in stick force above approximately 20 deg. total aileron deflection.
Date: September 26, 1946
Creator: Yates, Campbell C. & Schneiter, Leslie E.