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Wind-Tunnel Tests of a Dual-Rotating Propeller Having One Component Locked or Windmilling

Description: "The effect on the propulsive efficiency of locking or windmilling one propeller of a six-blade dual-rotating propeller installation was determined in the Langley propeller-research tunnel. Tests were made of both pusher and tractor configurations, with the unpowered propeller both leading and following the powered propeller, which was set at a blade angle of 40 degrees. The maximum propulsive efficiency of the powered propeller in combination with the locked or windmilling propeller was, in al… more
Date: January 1945
Creator: Bartlett, Walter A., Jr.
Item Type: Refine your search to only Report
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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… more
Date: December 26, 1946
Creator: Queijo, M. J.
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of a Piston-Type Control Booster on an Airfoil and Aileron Model

Description: "Measurements of control moments were made in the NACA stability tunnel to determine the operational characteristics of a piston-type control booster on an aileron. The booster was so constructed and installed that pressures picked up from the air stream below the wing acted on a pair of pistons. The data are presented in the form of curves of pressure coefficients acting on the pistons, hinge-moment coefficients, and booster coefficients plotted against aileron deflection" (p. 1).
Date: November 1943
Creator: Bird, J. D. & Mendelsohn, Robert A.
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of a Portion of a PV-2 Helicopter Rotor Blade

Description: From Summary: "A portion of a PV-2 helicopter rotor blade has been tested in the 6- by 6-foot test section of the Langley stability tunnel to determine if the aerodynamic characteristics were seriously affected by cross flow or fabric distortion. The outer portion of the blade was tested as a reflection plane model pivoted about the tunnel wall to obtain various angles of cross flow over the blade. Because the tunnel wall acts as a plane of symmetry, the measured aerodynamic characteristics cor… more
Date: March 29, 1945
Creator: Kemp, William B., Jr.
Item Type: Refine your search to only Report
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Wind Tunnel Tests of a Submerged-Engine Fuselage Design

Description: Report presenting tests conducted in the 8-foot high-speed wind tunnel of a scale model pursuit-type fuselage with practicable internal duct arrangement designed to meet all of the air requirements of a 1000-horsepower radial engine submerged at the maximum section. The results showed that the required internal flow can be obtained with negligible ducting losses provided that basic principles are observed in designing the air passages.
Date: October 1940
Creator: Becker, John V. & Baals, Donald D.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
open access

Wind-Tunnel Tests of a Twin-Engine Model to Determine the Effect of Direction of Propeller Rotation on the Static-Stability Characteristics

Description: Report presenting tests made in the 7- by 10-foot tunnel to determine the effect of direction of propeller rotation on the static longitudinal and lateral stability characteristics of the scale model of the North American B-28 airplanes. The results of the present investigation indicate that the mode of propeller operation has a considerable effect upon lateral and longitudinal stability and may have an effect upon propulsive efficiency.
Date: January 1943
Creator: Rogallo, Francis M. & Swanson, Robert S.
Item Type: Refine your search to only Report
open access

Wind Tunnel Tests of Ailerons at Various Speeds 1: Ailerons of 0.20 Airfoil Chord and True Contour With 0.35 Aileron-Chord Extreme Blunt Nose Balance on the NACA 66,2-216 Airfoil

Description: "Hinge-moment, lift, and pressure-distribution measurements were made in the two-dimensional test section of the NACA stability tunnel on a blunt-nose balance-type aileron on an NACA 66,2-216 airfoil at speeds up to 360 miles per hour corresponding to a Mach number of 0.475. The tests were made primarily to determine the effect of speed on the action of this type of aileron. The balance-nose radii of the aileron were varied from 0 to 0.02 of the airfoil chord and the gap width was varied from 0… more
Date: June 1943
Creator: Letko, W.; Denaci, H. G. & Freed, C.
Item Type: Refine your search to only Report
open access

Wind-tunnel tests of ailerons at various speeds 2: ailerons of 0.20 airfoil chord and true contour with 0.60 aileron-chord sealed internal balance on the NACA 66,2-216 airfoil

Description: Report presenting hinge-moment, lift, pressure difference across the balance, and pressure-distribution measurements in the two-dimensional test section of the stability tunnel on a 0.60 aileron-chord sealed internal-balance aileron on a specified NACA airfoil. The primary test objective was to determine the effect of speed on the action of the aileron.
Date: June 1943
Creator: Denaci, H. G. & Bird, J. D.
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of Ailerons at Various Speeds 3: Ailerons of 0.20 Airfoil Chord and True Contour With 0.35-Aileron-Chord Frise Balance on the NACA 23012 Airfoil

Description: Report presenting hinge moment, lift, and pressure-distribution measurements made on a Frise aileron on an NACA 23012 airfoil in the two-dimensional test section of the stability tunnel. Speeds up to 360 miles per hour corresponding to a Mach number of about 0.470 were used.
Date: September 1943
Creator: Letko, W. & Kemp, W. B.
Item Type: Refine your search to only Report
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Wind Tunnel Tests of Ailerons at Various Speeds 4: Ailerons of 0.20 Airfoil Chord and True Contour With 0.35 Aileron-Chord Extreme Blunt-Nose Balance on the NACA 23012 Airfoil

Description: Report presenting tests made on an NACA 23012 airfoil fitted with a 20-percent-chord, true-contour aileron with 35-percent-chord, extreme blunt-nose balance. The primary purpose of the investigation was to determine the variation of the aerodynamic characteristics of this type of aileron with airspeed; the effect of variations of gap width and balance-nose radii was also investigated. Results regarding hinge moments, lift, and pitching-moment coefficients are provided.
Date: August 1943
Creator: Anderson, R. A.
Item Type: Refine your search to only Report
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Wind Tunnel Tests of Ailerons at Various Speeds 5: Pressure Distributions Over the NACA 66,2-216 and NACA 23012 Airfoils With Various Balances on 0.20-Chord Ailerons

Description: Report presenting pressure distribution testing of an NACA 66,2-216, a = 1.0 airfoil equipped with a blunt nose balance aileron and a sealed internal-balance aileron and of an NACA 23012 airfoil equipped with a Frise aileron and a blunt nose balance aileron in the stability tunnel. Results regarding the section pressure distribution and section loads and moments are provided.
Date: November 1943
Creator: Letko, W. & Denaci, H. G.
Item Type: Refine your search to only Report
open access

Wind tunnel tests of air inlet and outlet openings on a streamline body

Description: Report presenting testing in the 8-foot high-speed wind tunnel to determine the effect on external drag and pressure distribution of air inlet openings on the stagnation point of a streamline body. The results showed that external drag of the body with suitably designed nose-inlet and tail-outlet openings over a wide range of rates of internal air flow was no higher than the drag of the streamline body. Specific results for the streamline body, nose-inlet openings, outlet openings, and inlet-ou… more
Date: November 1940
Creator: Becker, John V.
Item Type: Refine your search to only Report
open access

Wind tunnel tests of an NACA 23021 airfoil equipped with a slotted extensible and a plain extensible flap

Description: "An investigation has been made in the NACA 7- by 10-foot wind tunnel of a large chord NACA 23021 airfoil equipped with two arrangements of a completely extended 15 percent chord extensible flap. One of the flaps had a faired juncture, without a gap; the other was provided with a slot between the trailing edge of the airfoil and the nose of the flap. The results showed that the basic airfoil gave the lowest profile-drag coefficients over the low lift range, the airfoil with the plain extensible… more
Date: November 1940
Creator: Swanson, Robert S. & Harris, Thomas A.
Item Type: Refine your search to only Report
open access

Wind-tunnel tests of dual-rotating propellers with systematic differences in number of blades, blade setting, and rotational speed of front and rear propellers

Description: Report presenting the results of aerodynamic tests of seven-blade propellers which were considered as a possible arrangement to avoid vibration difficulties. Variations of relative blade angle and rotational speeds of the front and rear components of a six-blade dual-rotating propeller were also investigated.
Date: May 1944
Creator: Gray, W. H.
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of Eight-Blade Single and Dual-Rotating Propellers in the Tractor Position

Description: Tests of 10-ft. diameter, eight-blade, single - and dual - rotating propellers were conducted in 20-ft propeller research tunnel. Propellers were mounted at front end of a streamline body in spinners that covered hubs and parts of shanks. Effect of a symmetrical wing mounted in slipstream was investigated. Blade-angle settings ranged from 20 Degrees to 65 Degrees. Results indicated that dual rotation resulted in gains of from 1 to 8 percent in efficiency over single rotation for eight-blade pro… more
Date: November 1941
Creator: Biermann, David & Gray, W. H.
Item Type: Refine your search to only Report
open access

Wind-Tunnel Tests of Four- and Six-Blade Single- and Dual-Rotating Tractor Propellers

Description: "Test of 10-foot diameter, four and six blade single-rotating and dual-rotating propellers were conducted in the NACA propeller-research tunnel. The propellers were mounted at the front end of a streamline body incorporating spinners to house the hub portions. The effect of a symmetrical wing mounted in the slipstream ranged from 20 degrees to 65 degrees setting corresponds to airplane speeds greater than 500 miles per hour. The results indicate that dual-rotating propellers were from 0 to 6 pe… more
Date: July 13, 1942
Creator: Biermann, David & Hartman, Edwin P.
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of Four Curtiss Propellers Embodying Different Blade Sections

Description: Tests of four 10-foot propellers were made in the propeller-research tunnel for the Army Air Corps to check flight and static thrust test results made on several propellers embodying Clark Y and modified NACA 16-series sections. These propellers were identical as to diameter and activity factor and very closely identical in thickness ratio and pitch distribution. The blades embodied sections with both single- and double-cambered Clark Y, modified NACA 16-series, and a combination of Clark Y and… more
Date: August 1941
Creator: Gray, W. H.
Item Type: Refine your search to only Report
open access

Wind-tunnel tests of four full-scale seaplane floats

Description: Report presenting wind tunnel testing of four full-scale seaplane floats to determine the aerodynamic characteristics of the floats and to evaluate several drag-reducing refinements. Four floats were investigated; two differed only in external details like flush rivets, while one was the type used on twin-float installations. The variation of lift, drag, and pitching moment with pitch angle are presented for each float.
Date: July 1943
Creator: Conway, Robert N. & Maynard, Julian D.
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of Several Arrangements of External Auxiliary Fuel Tanks on a Fighter-Type Airplane

Description: Report presenting an investigation conducted in the 19-foot pressure tunnel to determine the aerodynamic effects of several arrangements of external auxiliary fuselage and wing tanks of large fuel capacity on a fighter-type airplane. The rectangular tank arrangement of 350-gallon fuel capacity has the greatest adverse aerodynamic effect on the airplane and is the least desirable of all the configurations tested.
Date: August 1942
Creator: Pepper, Edward
Item Type: Refine your search to only Report
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Wind-Tunnel Tests of Several Model Tractor-Propeller and Pusher-Propeller Wing Extension-Shaft Arrangements, Special Report

Description: "Tests were made in the 20-foot propeller-research tunnel to investigate the possibility of obtaining increased net efficiencies of propeller-nacelle units by enclosing the engines in the wings and by using extension shafts. A wing of 5-foot chord was fitted with a propeller drive assembly providing for several axial locations of tractor propellers and pusher propellers. A three-blade 4-foot propeller and a three-blade 3 1/2-foot propeller of special design were tested in this wing with spinner… more
Date: June 1941
Creator: Harmon, Hubert N.
Item Type: Refine your search to only Report
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Wind-tunnel tests of single- and dual-rotating pusher propellers having from three to eight blades

Description: Report presenting tests of 10-foot-diameter, single- and dual-rotating pusher propellers with three to eight blades that were conducted in the 20-foot propeller research tunnel as a continuation of previous investigations of tractor propellers. The propellers were mounted at the rear end of a streamline body in spinners that covered the hubs and part of the shanks. The effects as compared to previous testing differed only in degree of effect size.
Date: February 1942
Creator: Gray, W. H.
Item Type: Refine your search to only Report
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