UNT Libraries Government Documents Department - 338 Matching Results
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- Power-Off Tests of the Northrop N9M-2 Tailless Airplane in the 40- by 80-Foot Wind Tunnel
- Report discussing tests on the N9M-2 airplane to evaluate the airplane efficiency factor and to investigate the characteristics of the aeroboost in the elevon control system. The efficiency factor compared reasonably well to conventional airplanes and the aeroboost system and valve-chatter tests were satisfactory.
- Flight Tests of the High-Speed Performance of a P-51B Airplane (AAF No. 43-12105)
- Report discussing testing to check the improvement of 3 or 4 miles per hour in the maximum speed of the P-51B airplane as a result of sealing the wing-gun access doors and flap-spar lightening holes. Large variations in speed were observed during testing, so additional testing and analysis was carried out to determine the effects of various factors that were suspected of contributing to the inconsistency of the plane's performance.
- Pressure-Distribution Measurements of a Model of a Davis Wing Section with Fowler Flap Submitted by Consolidated Aircraft Corporation
- Wing pressure distribution diagrams for several angles of attack and flap deflections of 0 degrees, 20 degrees, and 40 degrees are presented. The normal force coefficients agree with lift coefficients obtained in previous test of the same model, except for the maximum lifts with flap deflection. Pressure distribution measurements were made at Reynolds Number of about 6,000,000.
- Pressure-distribution measurements of two airfoil models with Fowler flaps submitted by Consolidated Aircraft Corporation as alternative wing sections of the XB-32 airplane
- Report presenting pressure distribution measurements on two 24-inch chord models equipped with Fowler flaps in the two-dimensional low-turbulence pressure tunnel. Results regarding pressure-distribution diagrams and normal-force and moment coefficients are provided.
- Pressure-Distribution Measurements of a Low-Drag Airfoil With Slotted Flap Submitted by Curtiss-Wright Corporation
- "Pressure-distribution measurements were made at the request of the Materiel Division, U.S. Army Air Corps, on a 24-inch-chord wooden model equipped with a slotted flap and submitted by the Curtiss-Wright Corporation. The tests were made in the Langley two-dimensional tunnel at a Reynolds number of about 5,600,000" (p. 1).
- Some Flight Measurements on Pressure Distribution During Tail Buffeting
- Report presenting pressure-distribution measurements obtained from the horizontal tail surfaces of the Curtiss P-40K airplane during low-speed pull-ups to abrupt stall in which tail buffeting was experienced. The chordwise load distributions during buffeting are similar to those experienced during angle-of-attack changes. The location of the stall and frequency of stall disturbances are also described.
- Flutter tests of B-34 fin-rudder-tab system
- From Summary: "Tests on the B-34 fin-rudder-tab assembly were performed in the NACA 8-foot high-speed tunnel. Two cases of tab flutter were studied. It was shown conclusively that the frequency of the original or heavy tab was too low and caused coupling with one of the lower bending frequencies. A general conclusion was made that the tab frequency should be considerably higher than the lower modes of the fin-rudder assembly because there is generally a weaker coupling between the tab and the higher mode responses."
- The High-Speed Characteristics of Several Flaps and Spoilers on the Upper Surface of the Horizontal Stabilizer of a Model of a Radial-Engine Pursuit Airplane
- Report discussing an investigation into several types and sizes of flaps and spoilers located forward of the elevators on the upper surface of the horizontal stabilizer of a model of a radial-engine pursuit airplane. Information about the elevator characteristics, elevator-fixed and elevator-free balance lift coefficient, and trim drag coefficient for a range of Mach numbers is provided.
- Flight tests of various tail modifications on the Brewster XSBA-1 airplane 3: measurements of flying qualities with tail configuration 3
- Report presenting a series of tests on the Brewster XSBA-1 airplane to determine the effects of various tail modifications. Some of the modifications include variations of the chord of the elevator and rudder while the span and total area of the surfaces are kept constant and variations of the total area of the vertical tail surface. Results regarding the longitudinal stability and control and lateral stability and control are provided.
- Wind-tunnel investigation of an NACA 23012 airfoil with a 30 percent chord Maxwell slate and with trailing-edge flaps
- Report presenting an investigation in the 7- by 10-foot wind tunnel of an NACA 23012 airfoil with a 30 percent-chord Maxwell leading-edge slat and a slotted and a split flap. The main purpose was to determine the optimum slot cap of the Maxwell slat for, and the aerodynamic section characteristics of, the airfoil with several deflections for both types of flaps. Curves of lift, drag, and pitching-moment characteristics for optimum arrangements are provided.
- Wind-tunnel investigation of an NACA 23012 airfoil with an 18.05 percent chord Maxwell slat and with trailing-edge flaps
- Report presenting an investigation in the 7- by 10-foot wind tunnel of an NACA 23012 airfoil with an 18.05-percent-chord Maxwell leading-edge slat and with a slotted and a split flap. The main purpose of the investigation was to determine the optimum slot gap of the Maxwell slat for, and the aerodynamic section characteristics of, the airfoil with several deflections of both types of flap.
- Airfoil Section Data From Tests of 10 Practical-Construction Sections of Helicopter Rotor Blades Submitted by the Sikorsky Aircraft Division, United Aircraft Corporation
- Report presenting 10 practical-construction models of sections of helicopter rotor blades tested in the NACA two-dimensional low-turbulence pressure tunnel at atmospheric pressure. Lift, drag, and pitching-moment characteristics of blades representing the present method of construction of the YR-4A helicopter were determined.
- 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
- 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.
- Drag measurements at high Reynolds numbers of a 100-inch-chord NACA 23016 practical construction wing section submitted by Chance Vought Aircraft Company
- Report presenting drag measurements in the two-dimensional low-turbulence tunnel of an available 100-inch-chord model of the NACA 23016 wing section. Results regarding the curves of section drag coefficient plotted against Reynolds number for various surface conditions and lift coefficients, variation of drag coefficient with lift coefficient, and effects of skin friction are provided.
- Flight measurements of horizontal tail loads on a typical propeller-driven pursuit airplane during stalled pull-outs at high speed
- Report presenting flight measurements of the pressures on the horizontal tail surfaces of a typical propeller-driven pursuit airplane during stalled pull-outs at high Mach number. Unit loads measured on the stabilizer at safe maneuvering limits were not only considerably in excess of the design unit loads, but also occurred in a direction opposite to the design loads. Revision of the tail-load design requirements and manner of specifying safe maneuverability limits to pilots appears necessary.
- Estimates of the Vertical-Tail Loads of a Bell P-63A-1 Airplane (AAF No. 42-68889) in Accelerated Rolling Maneuvers Based on Flight Tests With Two Vertical-Tail Arrangements
- Report discussing the results of using an enlarged vertical tail on a P-63A-1 on directional stability. The tests included measurements of the amount of sideslip at various speeds and normal accelerations. Potential required modifications for increased performance using the larger tail are also described.
- Vibration Surveys of the P-40 Rudder and Fin-Rudder Assembly
- "The following surveys on the vibration response of the P-40 rudder and fin-rudder assembly were conducted during the fall of 1942 for the purpose of obtaining information on the flutter characteristics of high-speed airplanes of known performance. The tests on the rudder alone were made with the rudder suspended in a floating condition; the tests on the fin-rudder unit were made with the fin rigidly fastened to a concrete base" (p. 1). A variety of figures and diagrams for the assembly are provided.
- Flight Tests of a Rudder With a Spring Tab on an F6F-3 Airplane (BuAer No.04776)
- 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.
- Preliminary Vibration and Flutter Studies on P-47 Tail
- Report presenting a report illustrated by photographs and vibration records on the failure of the P-47 rudder in the high-speed tunnel at a true speed of 468 miles per hour and a density corresponding to 9000 feet altitude. The fin-rudder unit was tested as being at least representative of the tail design of the P-47 airplane.
- Vibration Surveys of the P-47-B Rudder and Fin-Rudder Assembly
- Report presenting a study of the flutter characteristics of the P-47 tail assembly, which included replacing the original fabric-covered rudder with a metal-covered rudder and reinforcing the fin. Figures are provided for different configurations and the cycles per second under the same conditions are provided.
- Flight Investigation of Modifications to Improve the Elevator Control-Force Characteristics of the Curtiss SB2C-1C Airplane in Maneuvers
- Report discussing tests on three sets of elevators with various combinations of section contour, balancing tabs, bobweights, and control-system mechanical advantage on an SB2C-1C airplane. Effects on maneuvering stability, a comparison of production elevators and recommended arrangement, and internal elevator pressures are described.
- The Aerodynamic Tests of Three Edo Floats for the SB2U-3, 0S2U-2, and XSB2C-2 Seaplanes - NACA Models 106-K, 107-K, and 125-AH
- Report presenting aerodynamic testing of scale models of the Edo seaplane floats for the SB2U-3, OS2U-2, and XSB2C-2 seaplanes. Various coefficients, pitching moment, yawing moment, and drag coefficients are provided.
- Analytical investigation of the stability of an F8F dropping model with automatic stabilization
- From Introduction: "All results are presented in the form of motions following abrupt displacements of fixed magnitude - 20^o in bank and 15^o in pitch and yaw - from the reference attitude."
- Flight tests of beveled-trailing-edge ailerons with various modifications on a North American XP-51 airplane (AAF No.41-38)
- Report presenting flight testing using a North American XP-51 airplane with several arrangements of beveled-trailing-edge ailerons to determine the most satisfactory arrangement. Results regarding the aileron configuration, trimming tabs, and factors affecting symmetry of aileron characteristics are provided.
- Wind-Tunnel Investigation of a Beveled Aileron Shape Designed to Increase the Useful Deflection Range
- Report presenting a wind tunnel investigation of a beveled aileron shape designed to increase the useful deflection range. The purpose of the investigation was to determine the general aerodynamic characteristics of this aileron and, in particular, to determine its useful angular range. Results regarding the effect of the hinge-gap seal, the surface condition and Reynolds number, and effect of aileron profile are provided.
- Tests of a 0.1475c Aileron With a Tab on Low-Drag Section for Curtiss XP-60 Airplane in the Low-Turbulence Tunnel
- "Preliminary two-dimensional tests of the hinge-moment characteristics of a 0.1725c internally balanced aileron on the subject XP-60 wing section indicated that more internal balance would be required if light stick forces were to be obtained at high speeds. The present series of tests were therefore undertaken in order to investigate methods of reducing the slope of the hinge-moment curve while still maintaining the required aileron effectiveness" (p. 1).
- Two-Dimensional Wind-Tunnel Investigation of Spoiler Aileron Flap Model for the Hughes XF-11 Airplane
- Report discussing testing on a retractable spoiler aileron on the NACA 66(215)-216 airfoil with a 25-percent-chord slotted flap. The effects of spoiler thickness, spoiler gap, spoiler bevel angle, spoiler roughness, and flap deflection on aerodynamic characteristics are described.
- Measurement of Individual Aileron Hinge Moments and Aileron Control Characteristics of a P-40F Airplane
- "Flight measurements have been made of the individual aileron hinge moments, aileron rolling effectiveness pb/2V ,and stick-force characteristics in abrupt aileron rolls with a P-40F airplane (AAF No. 41-14119) over an indicated airspeed range from 108 to 304 miles per hour. Three methods for measuring the rate of change of hinge moment with angle of attack were investigated. Presented for comparison with the flight results are data from two-dimensional wind-tunnel tests of the wing-aileron profile as measured at the center aileron hinge" (p. 1).
- An Investigation of the Mutual Interference Effects of a Tail-Surface: Stern Propeller Installation on a Model Simulating the Douglas XB-42 Empennage
- Report discussing the mutual interference effects of tail surfaces and a stern propeller on a model of the XB-42.The main focus was to determine the effect of tail surface-propeller spacing upon the periodic tail surface loading coincident with propeller blade passage.
- Calculation of the Aileron and Elevator Stick Forces and Rudder Pedal Forces for the Bell XP-83 Airplane (Project MX-511) in Spins
- "Aileron and elevator stick forces and rudder pedal forces for the Bell XP-83 airplane in spins have been calculated. The results indicate that the aileron and elevator stick forces may be excessive unless some suitable booster or more highly balanced control surfaces are used. The pilot will be able to move the surfaces only slightly from their normal floating locations" (p. 1).
- High-Speed Wind-Tunnel Tests of Semispan Horizontal Tails With Fabric-Covered and Metal-Covered Elevators for a Bomber Airplane
- "This report contains the results of tests of a full-scale semispan horizontal tail plane of a bomber airplane. The effects of fabric distortion on the aerodynamic characteristics of the elevator are determined by comparing the aerodynamic characteristics of a fabric-covered elevator with those of a metal-covered elevator. In addition, the results of cutting holes in the balance seal, the effect of fixing transition, the tab effectiveness both sealed and unsealed, and the section drag of this tail plane are presented" (p. 1).
- Wind-tunnel investigation of a section of the horizontal tail surface for the Bell XP-63 airplane
- Report presenting force tests conducted on a model of a section of the XP-63 horizontal tail surface in the 4- by 6-foot closed-throat vertical wing tunnel. The angle-of-attack range was from the negative to the positive stall for all flap deflections.
- Test of 0.14-Scale Models of the Control Surfaces of Army Project MX-511 in Attitudes Simulating Spins
- Report discussing the aerodynamic characteristics of the wing and isolated tail of the Bell XP-83 airplane in attitudes simulating spin conditions. Information about the the aileron hinge moment, angle of attack, and elevator hinge-moment is provided.
- Flight Tests of Various Tail Modifications on the Brewster XSBA-1 Airplane 2: Measurements of Flying Qualities with Tail Configuration Number Two
- Several tail modifications of the Brewster XSBA-1 scout-bomber were investigated and results compared. Modifications consisted of variation of the chord of the elevator and rudder while the total area of the surfaces is kept constant and variations of the total area of the vertical tail surface. Configuration number 2 reduced trim changes by 50 percent and reduced average elevator control force gradient from 30 to 27 pounds/g. Stick travel required to stall in maneuver was 4.6 inches.
- Wind-tunnel investigation of profile drag and lift of an intermediate wing section of the XP-51 airplane with beveled trailing-edge and contour ailerons
- Report presenting the results of flight investigations showing that a beveled trailing-edge aileron gives as low or a lower profile drag than a contour aileron. Section profile drag and lift coefficients with two different types of ailerons were obtained at 3 different Reynolds numbers.
- Aerodynamic Data for a Wing Section of the Republic XF-12 Airplane Equipped With a Double Slotted Flap
- Report presenting an investigation in the two-dimensional low-turbulence tunnels for the purpose of developing an optimum flap configuration for maximum lift on an airfoil section for the Republic XF-12 airplane equipped with a double slotted flap. Lift and flap loads were obtained at several flap deflections for two flap paths. Results regarding lift, drag, and flap loads are provided.
- Two-Dimensional Wind-Tunnel Investigation of Two NACA Low-Drag Airfoil Sections Equipped With Slotted Flaps and a Plain NACA Low-Drag Airfoil Section for XF6U-L Airplane
- Report discussing the results of testing to determine the aerodynamic characteristics of three NACA-designed airfoil sections, some with flaps equipped. The tests included determination of the aerodynamic characteristics of the airfoils in smooth conditions and with standard roughness applied to the leading edge. Lift tests were also carried out at a range of flap deflections.
- Two-dimensional wind-tunnel investigation of 0.20-airfoil-chord plain ailerons of different contour on an NACA 65(sub 1)-210 airfoil section
- 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.
- Aerodynamic Tests of an NACA 66(215)-116, a=0.6 Airfoil With a 0.25c Slotted Flap for the Fleetwings XA-39 Airplane
- Report presenting testing in the two-dimensional low-turbulence tunnels on a 24-inch-chord model of the NACA 66(215)-116 a = 0.6 airfoil with a 0.25-chord slotted flap. The optimum flap pivot positions were found for three different conditions. The conditions were determined from a consideration of the landing, take-off, and strafing requirements of the airplane.
- Investigation of surface irregularities on an NACA 63(420)-416, a=1.0 airfoil section for the Glenn L. Martin Company design 195
- Report presenting the results of an investigation made in the two-dimensional low-turbulence pressure tunnel of surface irregularities on a low-drag airfoil section. The primary objective was to determine the effects of riveted and piano-hinge-type skin joints and of an aileron slot of the drag characteristics. Any type of surface irregularities at the front spar were found to cause substantial increase in drag.
- A Flight Investigation of the Stability of a Towed Body
- Report presenting flight tests to determine whether a towed body that was designed to meet certain specifications met the stability specification, which required that angular deviations in flight should be less than 1 degree. The requirement was met in flight in smooth air, but not in rough air, where the rolling motions were considerably larger.
- Some Notes on the Effects of Jet-Exit Design on Static Longitudinal Stability
- Report discussing several types of jet-exit designs, including normal, beveled, and unsymmetrical shapes, and their effect on the stability characteristics of the aircraft. No deviation of the jet center line from its exposed path is likely to be obtained if a jet exist is used that is normal to the flow. Having a tilted or asymmetrical exit was found to adversely affect the stability of the aircraft.
- An Investigation of the Air Flow Around a Martin PBM-3 Flying Boat by Means of Tufts
- Report presenting observations made of the air flow around a Martin PBM-3 flying boat. The observations are part of an analysis to aid in the determination of possible methods of reducing the air drag of the airplane. The behavior of the tufts on the hull and tip floats at various airplane speeds by still and moving pictures taken from an accompanying airplane.
- Control-Motion Studies of the PBM-3 Flying Boat in Abrupt Pull-Ups
- Report presenting a control-motion study in flight that is part of series covering a range of types and sizes of modern airplanes. This particular one involves the PBM-3 flying boat, which is equipped with a control mechanism typical of the cable-type systems in large transport, cargo, or bomber airplanes as well as those employed in flying boats. The elasticity of the elevator control system of the PBM-3 was such to limit the obtainable acceleration to about 3g for center-of-gravity positions in the usual operating range; that is, 26 to 30 percent mean aerodynamic chord, and for the range of airspeeds covered by the tests.
- Compression Tests of Six Curved Paper-Base Plastic Panels With Outward-Acting Normal Pressure
- Report presenting results of compression tests of six paper-base plastic panels with outward-acting normal pressure. All panels failed by separation of the skin, either from the rib or from the stiffeners. Results regarding the introduction of air pressure and types of failures encountered are provided.
- A comparison of three spinner-diffuser designs in an NACA D(sub S) cowling for the Pratt & Whitney R-2800 engine
- Report presenting testing to determine which of three spinner-diffuser designs on an NACA cowling was the most effective in cooling a Pratt & Whitney R-2800 engine installation. The results of pressure-distribution studies in front of and behind each bank of cylinders are presented for a wide range of propeller-operating conditions.
- Static Characteristics of Curtiss Propellers Having Different Blade Sections
- Report presenting static tests on four full-scale two-bladed propellers differing only in blade sections at blade angles from 0 to 20 degrees at the three-quarters radius. Two of the propellers were also tested as three-bladed propellers. For all of the propellers tested, the highest value of the static thrust figure of merit occurred at a tip-speed ratio between 0.7 and 0.9; the highest efficiency in flight may be expected in the same range of tip-speed ratios.
- Static Characteristics of Hamilton Standard Propellers Having Clark Y and NACA 16 Series Blade Sections
- Report presenting static tests on two full-scale three-bladed propellers differing only in blade sections at blade angles from 0 to 20 degrees at the three-quarters radius.
- Tests of Cast Aluminum-Alloy Mixed-Flow Impellers
- "A machined mixed-flow centrifugal impeller of a relatively complex passage shape was used as a pattern to cast a number of aluminum-alloy impellers from two aluminum-base alloys (designated alloys 1 and 2) by the 'lost wax' process. An investigation was conducted to determine whether these cast impellers, could be considered satisfactory for use in compressors. The investigation included preliminary examination, physical tests, metallurgical examination, and performance tests" (p. 1).
- Air-flow and performance characteristics of the engine-stage supercharger of a double-row radial aircraft engine I: effect of operating variables
- From Introduction: "The tests reported herein, conducted during the early part of 1945, were made to determine the inherent charge-air distribution characteristics of the engine-stage supercharger of the double-row radial engine."