1,264 Matching Results

Search Results

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.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of control-surface characteristics 17: beveled-trailing-edge flaps of 0.20, 0.30, and 0.40 airfoil chord on an NACA 0009 airfoil

Description: Report presenting force tests in two-dimensional flow in the 4- by 6-foot vertical tunnel to determine the aerodynamic characteristics of an NACA 0009 airfoil with flaps having chord at 3 locations of the airfoil chord and three degrees of the beveled trailing edges. The results indicated that, with a smooth leading edge, the increased trailing-edge angle on the flaps with sealed gaps decreased the slope of the control-fixed lift curve and the lift effectiveness.
Date: April 1944
Creator: Lockwood, Vernard E.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of control-surface characteristics 13: various flap overhangs used with a 30-percent-chord flap in an NACA 66-009 airfoil

Description: Report presenting force tests in two-dimensional flow made on an NACA 66-009 airfoil with a flap having a chord 30 percent of the airfoil chord and a tab having a chord 20 percent of the flap chord. A plain flap and flaps having overhangs of 35 and 50 percent of the flap chord were tested with two gap variations: sealed and unsealed. Results regarding lift, flap hinge moments, pitching moments, drag, and tab characteristics are provided.
Date: July 1943
Creator: Gillis, Clarence L.
Partner: UNT Libraries Government Documents Department

Flight investigation at high Mach numbers of several methods of measuring static pressure on an airplane wing

Description: Report discusses an investigation into static pressures in subsonic and supersonic flow over an airplane wing as measured by static-pressure tubes, a static-pressure belt, and orifices flush with the wing surface. The results obtained from the three types of measuring devices and a comparison to theoretical calculations are presented.
Date: November 1944
Creator: Zalovcik, John A. & Daum, Fred L.
Partner: UNT Libraries Government Documents Department

Flight Investigation at High Speeds of Profile Drag of Wing of a P-47D Airplane Having Production Surfaces Covered with Camouflage Paint

Description: Wing section outboard of flap was tested by wake surveys in Mach range of 0.25 - 0.78 and lift coefficient range 0.06 - 0.69. Results indicated that minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach less than 0.67. Below Mach number at which compressibility shock occurred, variations in Mach of 0.2 had negligible effect on profile drag coefficient. Shock was not evident until critical Mach was exceeded by 0.025.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Partner: UNT Libraries Government Documents Department

Flight and test-stand investigation of high-performance fuels in double-row radial air-cooled engines 1: determination of cooling characteristics of flight engine

Description: Report discussing the cooling characteristics of a 14-cylinder double-row radial air-cooled engine in a four-engine airplane. The effects of charge-air flow, cooling-air pressure drop, and fuel-air ratio on the cooling characteristics were measured separately. The cooling equation, rear middle-barrel temperature, cooling-limited manifold pressure, and maximum cruising power versus temperature-limited power are described.
Date: December 20, 1944
Creator: Blackman, Calvin C.; White, H. Jack & Pragliola, Philip C.
Partner: UNT Libraries Government Documents Department

Flight and test-stand investigation of high-performance fuels in modified double-row radial air-cooled engines 1: determination of the cooling characteristics of the flight engine

Description: Report discussing the cooling characteristics of a modified 14-cylinder double-row radial air-cooled engine installed in a four-engine airplane at a pressure altitude of 7000 feet. Testing of the variable charge-air flow, variable cooling-air pressure drop, and variable fuel-air ratio was conducted. The cooling equation, temperature-limited performance, maximum engine temperatures, and other information predicted by calculations is described.
Date: July 9, 1945
Creator: Werner, Milton; Blackman, Calvin C. & White, H. Jack
Partner: UNT Libraries Government Documents Department

Flight and test-stand investigation of high-performance fuels in double-row radial air-cooled engines 2: flight knock data and comparison of fuel knock limits with engine cooling limits in flight

Description: Report discussing a comparison of the antiknock characteristics of triptane with a temperature-sensitive blending agent and of the fuel knock limits with engine cooling limits. Estimates were also made of temperature-limited engine performance at several flight and engine conditions.
Date: December 30, 1944
Creator: White, H. Jack; Blackman, Calvin C. & Werner, Milton
Partner: UNT Libraries Government Documents Department

Flight and test-stand investigation of high-performance fuels in modified double-row radial air-cooled engines 2: flight knock data and comparison of fuel knock limits with engine cooling limits in flight

Description: Report discussing tests on three fuels in a 14-cylinder double-row radial air-cooled engine at different engine speeds, blower ratios, and spark settings.
Date: August 4, 1945
Creator: White, H. Jack; Pragliola, Philip C. & Blackman, Calvin C.
Partner: UNT Libraries Government Documents Department

Flight measurements of the flying qualities of an F6F-3 airplane (BuAer No. 04776) 1: longitudinal stability and control

Description: Report discussing flight measurements of the handling qualities of an F6F-3 obtained over the course of thirty flights and under a variety of conditions. The longitudinal stability and control of the plane were found to be satisfactory by the test pilots. Information about the elevator control, flaps, and the longitudinal trimming device is provided in greater detail.
Date: February 13, 1945
Creator: Williams, Walter C. & Reeder, John P.
Partner: UNT Libraries Government Documents Department

Flight measurements of the flying qualities of an F6F-3 airplane (BuAer No. 04776) 2: lateral and directional stability and control

Description: Report discussing the lateral and directional stability and control of the F6F-3 airplane in a variety of flying conditions. Information about the control-free lateral oscillations, aileron control characteristics, maximum sideslip, dihedral effect, blow-up characteristics of the landing flaps, rudder, pitching moment, and power of the rudder trim tab and aileron trim tab is included.
Date: February 13, 1945
Creator: Williams, Walter C. & Reeder, John P.
Partner: UNT Libraries Government Documents Department

Flight measurements of the effect on elevator stick forces of stabilizer incidence and elevator rib spacing on the P-63A-1-BE series airplane

Description: From Summary: "Flight tests were made to determine the cause and correction for the unusual stick-free instability of the original production P-63 airplane in high-speed straight flight." The rib spacing and stabilizer incidence of the original design were found to increase instability. When they were both altered, stability was improved and fabric deflection was reduced, but stick forces were not substantially altered.
Date: October 1945
Creator: Johnson, Harold I. & Mungall, Robert G.
Partner: UNT Libraries Government Documents Department

Flight tests of a rudder with a spring tab on an F6F-3 airplane (BuAer No.04776)

Description: Report discussing testing on an F6F-3 with a spring-tab rudder to determine the directional stability and control characteristics. Using the spring-tab rudder was found to result in lower trim-force change with speed and lower pedal forces in sideslips than the original rudder. Pilots were found to prefer the maneuverability of this configuration.
Date: March 1945
Creator: Williams, Walter C.
Partner: UNT Libraries Government Documents Department

Flight Measurements to Determine Effect of a Spring-Loaded Tab on Longitudinal Stability of an Airplane

Description: In conjunction with a program of research on the general problem of stability of airplanes in the climbing condition, tests have been made of a spring-loaded tb which. is referred to as a ?springy tab,? installed on the elevator of a low-wing scout bomber. The tab was arranged to deflect upward with decrease in speed which caused an increase in the pull force required to trim at low speeds and thereby increased the stick-free static longitudinal stability of the airplane. It was found that the springy tab would increase the stick-free stability in all flight conditions, would reduce the danger of inadvertent stalling because of the definite pull force required to stall the airplane with power on, would reduce the effect of center-of-gravity position on stick-free static stability, and would have little effect on the elevator stick forces in accelerated f11ght. Another advantage of the springy tab is that it might be used to provide almost any desired variation of elevator stick force with speed by adjusting the tab hinge-moment characteristics and the variation of spring moment with tab deflection. Unlike the bungee and the bobweight, the springy tab would provide stick-free static stability without requiring a pull force to hold the stick back while taxying. A device similar to the springy tab may be used on the rudder or ailerons to eliminate undesirable trim-force variations with speed.
Date: February 1, 1946
Creator: Hunter, Paul A. & Reeder, John P.
Partner: UNT Libraries Government Documents Department

Flight tests of a glider model towed by twin parallel towlines

Description: From Summary: "The stability characteristics of a glider towed by twin parallel towlines have been studied in the NACA free-flight tunnel. A preliminary theoretical analysis of the stability of a glider restrained from yawing was followed by an experimental investigation of the stability of a model towed from fixed tunnel points in such a way as to simulate tow in level flight. The results of the tests confirm the theoretical analysis and indicate that a pilotless, stable, towed-glider system is possible when twin parallel towcables are used."
Date: April 1943
Creator: Pitkin, Marvin & McKinney, Marion O., Jr.
Partner: UNT Libraries Government Documents Department

Free-spinning, longitudinal-trim, and tumbling tests of 1/17.8-scale models of the Cornelius XFG-1 glider

Description: Report discussing testing on the spin and recovery characteristics, longitudinal-trimming characteristics at extreme angles of attack, and tumbling characteristics of a model of the Cornelius XFG-1 glider. The effects of loading, mass distribution, and center-of-gravity position were determined. They also explored the inverted spin characteristics and spin-recovery parachute requirements.
Date: January 1946
Creator: Stone, Ralph W., Jr. & Daughtridge, Lee T., Jr.
Partner: UNT Libraries Government Documents Department

Free-spinning-tunnel tests of a 1/23.75-scale model of the Douglas DC-3 airplane

Description: Report presenting testing of a model of the Douglas DC-3 airplane for several loading conditions. The load factor for the complete airplane, for the horizontal tail, and the force to start moving the elevator downward were estimated for some steady spins. Testing occurred at 2500 feet and 10,000 feet.
Date: June 1942
Creator: MacDougall, George F., Jr.
Partner: UNT Libraries Government Documents Department

Wind Tunnel Investigation of the Effects of Slot Shape and Flap Location on the Characteristics of a Low-Drag Airfoil Equipped with a 0.25-Chord Slotted Flap

Description: Tests were conducted at dynamic pressure of 50 lb per square foot with lift drag and pitch moment measurements throughout useful angle of attack range for constant flap deflection and position of a low-drag airfoil. Two slots were investigated and practical flap paths were selected for each Slot shape had a negligible effect on the maximum lift coefficient flap deflected, the rounded-entry slot had lower profile drag.
Date: December 1944
Creator: Holtzclaw, Ralph W. & Weisman, Yale
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of ailerons on a low-drag airfoil 1: The effect of aileron profile

Description: Report presenting an investigation in the 7- by 10-foot wind tunnel of the effects of various modifications to the profile of a 0.20-chord plain sealed aileron and a 0.15-chord plain sealed aileron on an NACA 66,2-216 airfoil. Thickening of the aileron was found to reduce the aileron effectiveness, reduce the slope of the wing section lift curve, and reduce the hinge-moment coefficients. Results regarding the section data, aileron effectiveness, aileron hinge moments, lift, pitching moment, drag, and Reynolds number are provided.
Date: January 1944
Creator: Crane, Robert M. & Holtzclaw, Ralph W.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of ailerons on a low-drag airfoil 2: the effect of thickened and beveled trailing edges

Description: Report presenting an investigation in the 7- by 10-foot wind tunnel of the effects of modifications to the trailing edge of a 0.20-chord plain sealed aileron on an NACA 66,2-216 airfoil. The modifications considered consisted of various amounts of symmetrical thickening and beveling of the aileron trailing edge. Results regarding aileron effectiveness, aileron hinge moments, aileron control forces, lift, pitching moment, drag, and Reynolds number are provided.
Date: January 1944
Creator: Crane, Robert M. & Holtzclaw, Ralph W.
Partner: UNT Libraries Government Documents Department

High-altitude cooling. 3 : Radiators

Description: Report details the methods of determining the heat-transfer rate, pressure drop, and drag power of high-altitude radiators. Performance charts are provided for a wide range of design variables.
Date: September 1944
Creator: Nielsen, Jack Norman
Partner: UNT Libraries Government Documents Department

Investigation of ice formation in the induction system of an aircraft engine 1: ground tests

Description: From Summary: "Ground tests were conducted on a twin-engine fighter airplane to study icing of an induction system incorporating an exhaust-driven turbosupercharger. The ground tests were made to determine the disposition of free water in the induction system of the airplane, to determine the charge-air heat rise available from the turbosupercharger, and to correlate actual airplane-test results with those of laboratory tests."
Date: March 1946
Creator: Essex, Henry A.; Zlotowski, Edward D. & Ellisman, Carl
Partner: UNT Libraries Government Documents Department