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  Partner: UNT Libraries Government Documents Department
 Serial/Series Title: NACA Research Memorandums
 Collection: Technical Report Archive and Image Library
Altitude-Wind-Tunnel Investigation of Performance of Several Propellers on YP-47M Airplane at High Blade Loading, 1, Aeroproducts H20C-162-X11M2 Four-Blade Propeller

Altitude-Wind-Tunnel Investigation of Performance of Several Propellers on YP-47M Airplane at High Blade Loading, 1, Aeroproducts H20C-162-X11M2 Four-Blade Propeller

Date: October 11, 1946
Creator: Saari, Martin J.
Description: An investigation was made in the Cleveland Altitude wind tunnel to determine the performance of an Aeroproducts H20C-162-X11M2 four-blade propeller on a YP-47M airplane at high blade loadings and high engine powers. The propeller characteristics were obtained for a range of power coefficients from 0.30 to 1.00 at free-stream Mach numbers of 0.40 and 0.50. The results of the force measurements are indicative only of trends in propeller efficiency with changes in power coefficient and advance-diameter ratio because unknown interference effects existed during the investigation. At a free-stream Mach number of 0.40, the envelopes of the efficiency curves decreased about 11% between advance-diameter ratios of 2.40 and 4.40. An increase in power coefficient from 0.30 to 0.80 at an advance-diameter ratio of 2.40 had little effect on the propeller efficiency. A change in power coefficient from 0.40 to 1.00 at an advance-diameter ratio of 4.40 increased the propeller efficiency by about 40%. For conditions below the stall the thrust loading on the outboard blade sections increased more rapidly than on the inboard sections as the power coefficient was increased or as the advance-diameter ratio was decreased. For conditions beyond the stall, the thrust loading decreased on the outboard sections and ...
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Langley Full-Scale Tunnel Investigation of a 1/3-Scale Model of the Chance Vought XF5U-1 Airplane

Langley Full-Scale Tunnel Investigation of a 1/3-Scale Model of the Chance Vought XF5U-1 Airplane

Date: October 11, 1946
Creator: Lange, Roy H.
Description: The results of an investigation of a 1/3-scale model of the Chance Vought XF5U-1 airplane in the Langley full-scale tunnel are presented in this report. The maximum lift and stalling characteristics of several model configurations, the longitudinal stability characteristics of the model, and the effectiveness of the control surfaces were determined with the propellers removed. The propulsive characteristics, the effect of propeller operation on the lift, and the static thrust of the model propellers were determined at several propeller-blade angles. The results with the propellers removed showed that the maximum lift coefficient of the complete model configuration was only 0.97 was compared with the value of 1.31 for the model configuration in which the engine-air ducts and canopy are removed. The model with the propellers removed (normal center-of-gravity position) has a positive static margin, stick fixed, varying from 5 to 13 percent of the mean aerodynamic chord throughout the unstalled range of lift coefficients. The unit horizontal tail is sufficiently powerful to trim the airplane with the propellers removed throughout the unstalled range of lift coefficients. The peak propulsive efficiencies for beta = 20 degrees and beta = 30 degrees were increased 7 percent at C(sub L) congruent to 0.67 ...
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Waters Loads on the XJL-1 Hull as Obtained in Langley Impact Basin, TED No. NACA 2413.3

Waters Loads on the XJL-1 Hull as Obtained in Langley Impact Basin, TED No. NACA 2413.3

Date: October 11, 1946
Creator: Steiner, Margaret F.
Description: An investigation was conducted in the Langley impact basin of the water loads on a half scale model of the XJL-1 hull whose forebody has a vee bottom with exaggerated chine flare. The impact loads, moments, and pressures were determined for a range of landing conditions. A normal full-scale landing speed of 86 miles per hour was represented with effective flight paths ranging from 0.6deg to 11.6deg. Landings were made with both fixed trim and free-to-trim mounting of the float over a trim range of -15deg to 12deg into smooth water and into waves having equivalent full-scale length. of 120 feet and heights ranging from 1 to 4 feet. All data and results presented in this report are given in terms of equivalent full-scale values. Summary tables and illustrative plots are used in presenting the material. The following maximum values of load and pressure are those which are apropos for effective flight paths less than 6.5deg which was the maximum value obtained in tests with the XJL-1 hull model representing full-scale landings with vertical velocity of 4.5 feet per second into 4-foot waves. The maximum local pressure on the flat portion of the bottom is 130 pounds per square inch ...
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Investigation of the performance of a 20-inch ram jet using preheated fuel

Investigation of the performance of a 20-inch ram jet using preheated fuel

Date: October 28, 1946
Creator: Perchonok, Eugene
Description: None
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Preliminary Tests of a Buffet Stall-Warning Device on a 1/5-Scale Model of the Republic XP-84 Airplane

Preliminary Tests of a Buffet Stall-Warning Device on a 1/5-Scale Model of the Republic XP-84 Airplane

Date: October 30, 1946
Creator: Tucker, Warren A.
Description: During the first flight tests of the Republic XP-84 airplane it was discovered that there was a complete lack of stall warning. A short series of development tests of a suitable stall-warning device for the airplane was therefore made on a 1/5-scale model in the Langley 300 MPH 7- by 10-foot tunnel. Two similar stall-warning devices, each designed to produce early root stall which would provide a buffet warning, were tested. It appeared that either device would give a satisfactory buffet warning in the flap-up configuration, at the cost of an increase of 8 or 10 miles per hour in minimum speed. Although neither device seemed to give a true buffet warning in the flaps-down configuration, it appeared that either device would improve the flaps-down stalling characteristics by lessening the severity of the stall and by maintaining better control at the stall. The flaps-down minimum-speed increase caused by the devices was only 1 or 2 miles per hour.
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Characteristics of a Sealed Internally Balanced Aileron from Tests of a 1/4-Scale Partial-Span Model of the Republic XF-12 Airplane in the Langley 19-Foot Pressure Tunnel

Characteristics of a Sealed Internally Balanced Aileron from Tests of a 1/4-Scale Partial-Span Model of the Republic XF-12 Airplane in the Langley 19-Foot Pressure Tunnel

Date: November 1, 1946
Creator: Graham, Robert R.
Description: This paper presents the results of the aileron investigation and includes rolling-moment, yawing-moment, and aileron hinge-moment coefficients and pressure coefficients across the aileron-balance seal through a range of angle of attack, tab deflection, and aileron deflection with flaps neutral and deflected 20 degrees and 55 degrees. Some of the effects of wing roughness and balance seal leakage on the aileron and tab characteristics are also presented.
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An Estimation of the Flying Qualities of the Kaiser Fleetwing All-Wing Airplane from Tests of a 1/7-Scale Model, TED No. NACA 2340

An Estimation of the Flying Qualities of the Kaiser Fleetwing All-Wing Airplane from Tests of a 1/7-Scale Model, TED No. NACA 2340

Date: November 1, 1946
Creator: Brewer, Gerald W.
Description: An investigation of a 1/7-scale powered model of the Kaiser Fleetwing all-wing airplane was made in the Langley full-scale tunnel to provide data for an estimation of the flying qualities of the airplane. The analysis of the stability and control characteristics of the airplane has been made as closely as possible in accordance with the requirements of the Bureau of Aeronautics, Navy Department's specifications, and a summary of the more significant conclusions is presented as follows. With the normal center of gravity located at 20 percent of the mean aerodynamic chord, the airplane will have adequate static longitudinal stability, elevator fixed, for all flight conditions except for low-power operation at low speeds where the stability will be about neutral. There will not be sufficient down-elevator deflection available for trim above speeds of about 130 miles per hour. It is probable that the reduction in the up-elevator deflections required for trim will be accompanied by reduced elevator hinge moments for low-power operation at low flight speeds. The static directional stability for this airplane will be low for all rudder-fixed or rudder-free flight conditions. The maximum rudder deflection of 30 deg will trim only about 15 deg yaw for most flight conditions ...
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Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms. IV - July 19, 1946 to July 20, 1946 at Orlando, Florida, Part 4, July 19, 1946 to July 20, 1946 at Orlando, Florida

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes within Thunderstorms. IV - July 19, 1946 to July 20, 1946 at Orlando, Florida, Part 4, July 19, 1946 to July 20, 1946 at Orlando, Florida

Date: November 1, 1946
Creator: Tolefson, H. B.
Description: Summaries of the gust and draft velocities evaluated from acceleration and airspeed-altitude records taken by NACA instruments installed n P-61c airplanes participating in thunderstorm flights 12 and 13 of July 19, 1946, and July 20, 1946, respectively, are presented in tables I and II herein. These data are of the type presented in reference 1 for previous flights. Inspection of the motion picture records of the pilots' instrument panels for the present flights indicated that the milliameter connected to equipment for measuring ambient air temperature read zero throughout all traverses.
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Effect of an Auxiliary Belly Fuel Tank on the Low-Speed Static Stability Characteristics of a 1/5-Scale Model of the Grumman XF8F-1 Airplane, TED No. NACA 2384

Effect of an Auxiliary Belly Fuel Tank on the Low-Speed Static Stability Characteristics of a 1/5-Scale Model of the Grumman XF8F-1 Airplane, TED No. NACA 2384

Date: November 5, 1946
Creator: Cook, Charles B.
Description: In.order to determine the aerodynamic effects of an auxiliary belly fuel tank on the Grumman F8F-1 airplane, a wind-tunnel investigation was made on a l/5 - scale model of the Grumman XF8F-1 airplane. Pitch and yaw tests were made with the model in the cruising and landing configurations for windmilling and take-off power conditions. Tuft studies and static-pressure measurements were also made to determine the flow characteristics in the region of the fuel tank. It was found that, at low speed, the auxiliary fuel tank test conditions, especially with power on in the landing configuration at high lift coefficients. The static directional stability was decreased for most test conditions, but the addition of a fairing between the fuselage and fuel tank improved the directional stability slightly in the power-on clean condition. The effective dihedral and lateral force were increased for most of the conditions tested. The tuft studies and pressure measurements indicated that the removal of the away braces would improve the.flow characteristics considerably in the region of the fuel tank end might also decrease the buffeting of the belly tank at high speeds.
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Evaluation of Gust and Draft Velocities from Flights of P-61c Airplanes within Thunderstorms. II - July 9, 1946 to July 11, 1946 at Orlando, Florida, II, July 9, 1946 to July 11, 1946 at Orlando, Florida

Evaluation of Gust and Draft Velocities from Flights of P-61c Airplanes within Thunderstorms. II - July 9, 1946 to July 11, 1946 at Orlando, Florida, II, July 9, 1946 to July 11, 1946 at Orlando, Florida

Date: November 5, 1946
Creator: Tolefson, Harold B.
Description: The results obtained from an evaluation for gust and draft velocities of acceleration and airspeed-altitude records taken by NACA recording instruments installed in P-61c airplanes participating in thunderstorm flights 6, 7, and 8 of July 9, 1946, July 10, 1946, and July 11, 1946, respectively, are presented herein. These data are summarized in tables I and II. In accordance with a recent discussion with a member of the U.S. Weather Bureau staff, the tabulated results for the present flight include in addition to data of the type presented in reference 1, the initial heading of the airplane for each traverse, the pressure altitude at the start of each traverse in increments of 500 feet, and the gust gradient distance when it could be evaluated. The cloud entry and exit times for the present data were taken from motion-picture records of the pilot's instrument panels whenever such records were available while the length fo the traverses in seconds and feet was taken from the airspeed-altitude records. In many cases, however, poor agreement is indicated between the duration of the cloud traverses as obtained from the motion-picture records and from the airspeed-altitude records. This result is believed to be due to camera ...
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