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Tests of a Heated Low-Drag Airfoil

Description: Report discusses the results of an experimental investigation into the NACA 65,2-016 heated wing. Information about the effect of heating on the drag coefficients, Reynolds numbers, and stability of the laminar boundary layer.
Date: December 1942
Creator: Frick, Charles W., Jr. & McCullough, George B.
Partner: UNT Libraries Government Documents Department

The Effect of Streamlining the Aterbody of an N.A.C.A. Cowling

Description: Report presenting an investigation of the drag and power cost associated with the changing of the nose of a nacelle from a streamline shape to a conventional cowling shape. Full-scale propellers and nacelles were used. The results of the tests showed that the streamline afterbody drag approached that of an airship form and that the added drag due to the open-nose cowling was only a quarter of the drag increase obtained with the other afterbody.
Date: December 1939
Creator: Stickle, George W.; Crigler, John L. & Naiman, Irven
Partner: UNT Libraries Government Documents Department

Preliminary Aerodynamic and Structural Tests Showing the Effect of Compressive Load on the Fairness of a Low-Drag Wing Specimen With Chordwise Hat-Section Stiffeners

Description: Report presenting an investigation that is part of a research program to obtain structures suitable for low-drag wings. The purpose of this particular investigation was to study the drag characteristics of an NACA 66(215)-(1.25)16 airfoil specimen of two-spar construction with hat-section chordwise stiffeners after a compressive load comparable with the maximum applied flight load of a modern military airplane has been applied and removed. Results regarding the variation of section drag coefficient with Reynolds number for the wing specimen of the airfoil, variation of section drag coefficient with section lift coefficient, and drag coefficients at specified Reynolds numbers are provided.
Date: December 1943
Creator: Davidson, Milton; Houbolt, John C.; Rafel, Normal & Rossman, Carl A.
Partner: UNT Libraries Government Documents Department

Extension of Useful Operating Range of Axial-Flow Compressors by Use of Adjustable Stator Blades

Description: "A theory has been developed for resetting the blade angles of an axial-flow compressor in order to improve the performance at speeds and flows other than the design and thus extend the useful operating range of the compressor. The theory is readily applicable to the resetting of both rotor and stator blades or to the resetting of only the stator blades and is based on adjustment of the blade angles to obtain lift coefficients at which the blades will operate efficiently. Calculations were made for resetting the stator blades of the NACA eight-stage axial-flow compressor for 75 percent of design speed and a series of load coefficients ranging from 0.28 to 0.70 with rotor blades left at the design setting" (p. 425).
Date: December 29, 1944
Creator: Sinnette, John T., Jr. & Voss, William J.
Partner: UNT Libraries Government Documents Department

The Design of Cooling Ducts With Special Reference to the Boundary Layer at the Inlet

Description: "A study has been made of underslung cooling ducts with special references to the problems presented by the boundary layer on the fuselage skin. It was found that good flow can be obtained in such ducts by (1) making the inlet opening of such size that the mean inlet velocity is about 0.6 the free-stream velocity and (2) providing vanes behind as well as ahead of the radiator. Tables to facilitate design are included, together with an example " (p. 1).
Date: December 1940
Creator: Katzoff, S.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of an NACA Low-Drag Tapered Wing With Straight Trailing Edge and Simple Split Flaps, Special Report

Description: Report discusses the results of an investigation to determine the effect of the split flaps on the aerodynamic characteristics of the tapered wing. The results indicated that values of maximum lift coefficient obtained from the NACA low-drag sections are comparable to values obtained on tapered wings with conventional sections. The addition of split flaps did not appreciably alter the pattern of the stall.
Date: December 1941
Creator: Muse, Thomas C. & Neely, Robert H.
Partner: UNT Libraries Government Documents Department

Tests of a Highly Cambered Low-Drag-Airfoil Section with a Lift-Control Flap, Special Report

Description: Tests were made in the NACA two-dimensional low turbulence pressure tunnel of a highly cambered low-drag airfoil (NACA 65,3-618) with a plain flap designed for lift control. The results indicate that such a combination offers attractive possibilities for obtaining low profile-drag coefficients over a wide range of lift coefficients without large reductions of critical speed.
Date: December 1942
Creator: Abbott, Ira H. & Miller, Ralph B.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of Control-Surface Characteristics 15: Various Contour Modifications of a 0.30-Airfoil-Chord Plain Flap on an NACA 66(215)-014 Airfoil

Description: Report presenting force-test measurements in two-dimensional flow made in the 4- by 6-foot vertical tunnel to determine the aerodynamic characteristics of an NACA 66(215)-014 airfoil equipped with true-contour, straight-contour, and beveled-trailing-edge flaps with chords 30 percent of the airfoil chord. The results are presented in the form of aerodynamic section characteristics for several flap deflections and for a sealed and unsealed gap at the flap nose.
Date: December 1943
Creator: Purser, Paul E. & Riebe, John M.
Partner: UNT Libraries Government Documents Department

Performance of NACA Eight-Stage Axial-Flow Compressor at Simulated Altitudes

Description: Report presenting an investigation to determine the design-performance characteristics of the eight-stage axial-flow compressor and the effect of altitude on the performance. The design pressure ratio of 5:1 was obtained at an adiabatic temperature-rise efficiency of 83 percent, a simulated altitude of 36,000 feet, and a compressor Mach number of 0.95.
Date: December 1944
Creator: King, J. Austin & Regan, Owen W.
Partner: UNT Libraries Government Documents Department

Drag and propulsive characteristics of air-cooled engine-nacelle installations for two-engine airplanes

Description: Report presenting a study on wing-nacelle propeller arrangements using a two-engine airplane with nacelles varying in diameter. Results regarding the power-off characteristics, propulsive and overall efficiencies, power-on characteristics, and pressure distributions are provided.
Date: December 1940
Creator: Wilson, Herbert A., Jr. & Lehr, Robert R.
Partner: UNT Libraries Government Documents Department

Charts for the determination of wing torsional stiffness required for specified rolling characteristics or aileron reversal speed

Description: "A series of charts are presented by which the wing torsional stiffness required to meet a given standard of rolling effectiveness may be quickly determined. The charts may also be used to obtain quickly the aileron reversal speed and the variation of the loss in rolling effectiveness with airspeed. The charts apply to linearly tapered wings and elliptical wings of tubular-shell construction having various aspect ratios with aileron span and location of ailerons as variables" (p. 457).
Date: December 1944
Creator: Pearson, Henry A. & Aiken, William S., Jr.
Partner: UNT Libraries Government Documents Department

A comparison at high speed of the aerodynamic merits of models of medium bombers having thickened wing roots and having wings with nacelles

Description: Report presenting testing of models of medium-bomber designs to investigate the relative characteristics of thickened wing roots with propeller-shaft fairings and wings with nacelles. Incremental drag coefficients due to thickened wing roots and due to propeller-shaft fairings through a range of Mach numbers at lift coefficient 0.10. Results regarding force tests, pressure-distribution tests, effect of thickening and filleting, nacelles and propeller-shaft fairings, and a comparison of submerged engines and engine-nacelle combinations are provided.
Date: December 1943
Creator: Draley, Eugene C.
Partner: UNT Libraries Government Documents Department

A flight investigation of NACA aileron modifications for the improvement of the lateral control characteristics of a high-speed fighter airplane

Description: Report presenting a flight investigation to improve the lateral control of a high-speed fighter airplane. Testing occurred with the original ailerons and a set of modified ailerons, which consisted of an increased balance chord and increased nose radius. The modified ailerons appear to offer a solution to the problem of aileron overbalance and oscillation in high-speed dives.
Date: December 1945
Creator: Williams, Walter C.
Partner: UNT Libraries Government Documents Department

Experimental constriction effects in high-speed wind tunnels

Description: From Summary: "An investigation has been conducted to determine the possible extent of effects of wind-tunnel constriction at high speeds for airfoils of various thickness-to-chord ratios at or near zero lift. The results indicate that a limiting test Mach number exists which is principally a function of the ratio of model thickness to tunnel height. At high Mach numbers serious constriction effects occur; these effects are of such a nature that the standard calibration methods given speeds much lower than the actual test speeds."
Date: December 1944
Creator: Byrne, Robert W.
Partner: UNT Libraries Government Documents Department

Two-dimensional wind-tunnel investigation of 0.20-airfoil-chord plain ailerons of different contour on an NACA 65(sub 1)-210 airfoil section

Description: Report presenting an investigation of three interchangeable sealed-gap 0.20-airfoil-chord plain ailerons of different contour on the NACA 65(sub 1)-210 airfoil section. The three aileron contours tested were the true airfoil contour, straight sides, and a beveled trailing edge. Results regarding the aileron effectiveness, aileron hinge moments, lift, pitching moment, and drag are provided.
Date: December 1945
Creator: Underwood, William J.; Braslow, Albert L. & Cahill, Jones F.
Partner: UNT Libraries Government Documents Department

Investigation of Flow in an Axially Symmetrical Heated Jet of Air

Description: The work done under this contract falls essentially into two parts: the first part was the design and construction of the equipment and the running of preliminary tests on the 3-inch jet, carried out by Mr. Carl Thiele in 1940; the second part consisting in the measurement in the 1-inch jet flow in an axially symmetrical heated jet of air.
Date: December 1943
Creator: Corrsin, Stanley
Partner: UNT Libraries Government Documents Department

Performance of an exhaust-gas "blowdown" turbine on a nine-cylinder radial engine

Description: Report presenting tests on an exhaust-gas turbine with four separate nozzle boxes each covering a 90 degree arc of the nozzle diaphragm and each connected to a pair of adjacent cylinders in a Pratt & Whitney R-1340-12 nine-cylinder radial engine. Results regarding the power output of the engine and turbine, effect of the turbine on engine power, turbine power output and speed characteristics, mean turbine efficiency, effect of the blowdown turbine on exhaust-gas temperature, and condition of the blowdown turbine after tests are provided.
Date: December 1944
Creator: Turner, L. Richard & Desmon, Leland G.
Partner: UNT Libraries Government Documents Department