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A flight study of requirements for satisfactory lateral oscillatory characteristics of fighter aircraft

Description: Report presenting a pilot-opinion survey conducted with a conventional fighter airplane fitted with special servo devices for varying in flight the dihedral effect, static directional stability, and directional damping. Results showing the boundaries that define satisfactory and tolerable lateral oscillatory characteristics are presented.
Date: July 25, 1951
Creator: Liddell, Charles J., Jr.; Creer, Brent Y. & Van Dyke, Rudolph D., Jr.
Partner: UNT Libraries Government Documents Department

A simplified instrument for recording and indicating frequency and intensity of icing conditions encountered in flight

Description: "An instrument for recording and indicating the frequency and intensity of aircraft icing conditions encountered in flight has been developed by the NACA Lewis Laboratory to obtain statistical icing data over world-wide air routes during routine airline operations. The operation of the instrument is based on the creation of a differential pressure between an ice-free total-pressure system and a total-pressure system in which small total-pressure holes vented to static pressure are allowed to plug with ice accretion. The simplicity of this operating principle permits automatic operation, and provides relative freedom from maintenance and operating problems" (p. 1).
Date: July 3, 1951
Creator: Perkins, Porter J.; McCullough, Stuart & Lewis, Ralph D.
Partner: UNT Libraries Government Documents Department

Effects of double-slotted flaps and leading-edge modifications on the low-speed characteristics of a large-scale 45 degrees swept-back wing with and without camber and twist

Description: Report presenting an investigation of two large-scale, semispan, wing-fuselage models with the 0.25-chord line swept back 45 degrees to determine and compare the effects of partial-span, double-slotted flaps on the characteristics of a 45 degree sweptback wing with and without camber and twist. A secondary investigation was also conducted to determine the effects of various full-span, leading-edge modifications on the characteristics of the models with and without the flaps.
Date: July 23, 1951
Creator: James, Harry A. & Dew, Joseph K.
Partner: UNT Libraries Government Documents Department

The use of two-dimensional section data to estimate the low-speed wing lift coefficient at which section stall first appears on a swept wing

Description: Report discusses a procedure for estimating the wing lift coefficient for and spanwise location of the first occurrence of section stall on a swept wing. It has been modified from a method used to calculate the same information for unswept wings. The effects of split flaps, leading-edge modifications, and fences are described.
Date: July 27, 1951
Creator: Maki, Ralph L.
Partner: UNT Libraries Government Documents Department

Experimental investigation of typical constant- and variable-area exhaust nozzles and effects on axial-flow turbojet-engine performance

Description: Report presenting testing of several turbojet engines with both constant- and variable-area nozzles to extend full-scale nozzle performance to higher exhaust-nozzle pressure ratios and to investigate the effects of constant- and variable-area nozzles on turbojet-engine operation. Results regarding the different types of nozzles are provided.
Date: July 9, 1951
Creator: Wallner, Lewis E. & Wintler, John T.
Partner: UNT Libraries Government Documents Department

System Analyses and Autopilot Design for Automatic Roll Stabilization of a Supersonic Pilotless Aircraft

Description: Memorandum presenting system analyses and autopilot design procedure for a supersonic pilotless aircraft with twin jet engines. The autopilots investigated were a gyro-actuated control, a gyro-actuated control with a rate-sensing device, and an electronic-hydraulic autopilot. Results regarding the airframe and gyro-actuated control system; airframe, gyro-actuated control, and rate servo; airframe and electronic-hydraulic autopilot; and contribution of method of analysis to system design are provided.
Date: July 11, 1951
Creator: Zarovsky, Jacob
Partner: UNT Libraries Government Documents Department

Control Performance of General Electric Fuel and Torque Regulator Operating on T31-3 Turbine-Propeller Engine in Sea-Level Test Stand

Description: A .General Electric fuel and torque regulator was tested in conjunction with a T31-3 turbine-propeller engine in the sea-level static test stand at the NACA Lewis laboratory. The engine and control were operated over the entire speed range: 11,000 rpm, nominal flight idle, to 13,000 rpm, full power. Steady-state and transient data were recorded and are presented with a description of the four control loops being used in the system. Results of this investigation indicated that single-lever control operation was satisfactory under conditions of test. Transient data presented showed that turbine-outlet temperature did overshoot maximum operating value on acceleration but that the time duration of overshoot did not exceed approximately 1 second. This temperature limiting resulted from a control on fuel flow as a function of engine speed. Speed and torque first reached their desired values 0.4 second from the time of change in power-setting lever position. Maximum speed overshoot was 3 percent.
Date: July 12, 1951
Creator: Oppenheimer, Frank L. & Lazar, James
Partner: UNT Libraries Government Documents Department

Supplementary Free-Spinning-Tunnel Investigation of a 1/30-Scale Model of the Grumman XF10F-1 Airplane in the Swept-Wing Configuration with Slats Extended

Description: A supplementary investigation has been conducted in the Langley 20-foot free-spinning tunnel of a 1/30 -scale model of the Grumman XFlOF-1 airplane to determine what effect full-span slats would have on the spin-recovery characteristics of the swept-wing version of the XFlOF-1 airplane, which had previously been indicated as possessing undesirable spin-recovery characteristics without slats. The effects of extended nose-wheel doors and of fairing the air-duct inlets were also determined. The results indicated that, with slats fully extended, satisfactory recovery could be obtained by rudder reversal provided it was accompanied by movement of the trimmer ailerons to full with the spin (only up-going spoiler operative), Extension of the nose-wheel doors or fairing of the air-duct inlets did not improve the recovery characteristics.
Date: July 24, 1951
Creator: Berman, Theodore
Partner: UNT Libraries Government Documents Department

An investigation of flow characteristics at Mach number 4.04 over 6- and 9-percent-thick symmetrical circular-arc airfoils having 30-percent-chord trailing-edge flaps

Description: Section data obtained from wind-tunnel tests at Mach number 4.04 and Reynolds numbers of about 5.0 times 10 to the 6th power and 8.4 times 10 to the 6th power are presented for 6- and 9-percent-thick symmetrical circular-arc airfoils with 30 percent chord trailing-edge flaps. Pressure distributions, Schlieren photographs, and force and moment coefficients are included.
Date: July 19, 1951
Creator: Ulmann, Edward F. & Lord, Douglas R.
Partner: UNT Libraries Government Documents Department

Low-speed investigation of several types of split flap on a 47.7 degree sweptback-wing - fuselage combination of aspect ratio 5.1 at a Reynolds number of 6.0 x 10(exp 6)

Description: Report presenting a low-speed wind-tunnel investigation to determine the longitudinal aerodynamic characteristics of a 47.7 degree sweptback wing-fuselage combination with split flaps and several modifications. The lift characteristics, pitching-moment characteristics, drag characteristics, and a comparison with flaps of the slotted type are included.
Date: July 10, 1951
Creator: Spooner, Stanley H. & Mollenberg, Ernst F.
Partner: UNT Libraries Government Documents Department

A finite step method for the calculation of span loadings of unusual plan forms

Description: Report presenting an investigation of the applicability of a finite-step method to the calculation of subsonic spanwise load distribution, lift-curve slope, lateral center of pressure, and aerodynamic center of unusual plan forms. The 20-step method was found to generally overestimate the amount of loading at the wing tip, but the lift-curve slope, lateral center of pressure, aerodynamic center, and loading shape generally agreed with lifting-surface results.
Date: July 16, 1951
Creator: Campbell, George S.
Partner: UNT Libraries Government Documents Department

Characteristics throughout the subsonic speed range of a plane wing and of a cambered and twisted wing, both having 45 degrees of sweepback

Description: Report presenting a wind-tunnel investigation of two semispan wing models with 45 degrees of sweepback, an aspect ratio of 5, and a taper ratio of 0.565. One wing had no camber or twist while the other was cambered for a design lift coefficient of 0.4 and twisted to relieve loading at the tip. Results regarding the plane wing, cambered and twisted wing, wing-body combinations, effect of camber and twist, effect of fences, effect of surface roughness, and lift-drag ratio are provided.
Date: July 12, 1951
Creator: Johnson, Ben H., Jr. & Shibata, Harry H.
Partner: UNT Libraries Government Documents Department

Effects of humidity during fabrication on some physical properties of glass-fabric unsaturated-polyester laminates

Description: Effects of humidity during fabric conditioning and during fabrication upon some physical properties of laminates prepared with glass fabric and an unsaturated polyester resin were investigated. Tests on these laminates included the measurement of flexural strength on the diagonal, both dry and after 7 days' immersion in water, specific gravity, resin content, percentage of voids, and total light transmission. Some data were also taken on lengthwise flexural strength.
Date: July 18, 1951
Creator: Wier, John E.; Pons, Dorothy C. & Axilrod, Benjamin M.
Partner: UNT Libraries Government Documents Department

Apparatus for obtaining a supersonic flow of very short duration and some drag measurements obtained with its use

Description: From Introduction: "The auxiliary apparatus described in this paper was constructed to meet this need and has been developed to a point where satisfactory measurements of relative drag can be obtained. In this paper, the apparatus is described and some comparisons are made between the results obtained with this apparatus and the measurements of free-fall, rocket, and supersonic-tunnel techniques."
Date: July 23, 1951
Creator: Yeates, John E., Jr.; Bailey, F. J., Jr. & Voglewede, T. J.
Partner: UNT Libraries Government Documents Department

An experimental investigation at subsonic speeds of a scoop-type air-induction system for a supersonic airplane

Description: Report presenting an investigation at subsonic speeds of a scoop-type air-induction system designed for use at subsonic and supersonic speeds. Measurements of the ram-recovery ratio and static pressures in a scoop-type intake on the upper surface of the fuselage were taken for a large range of mass-flow ratios, angles of attack, and angles of sideslip.
Date: July 19, 1951
Creator: Holzhauser, Curt A.
Partner: UNT Libraries Government Documents Department

Effects of spanwise thickness variation on the aerodynamic characteristics of 35 degree and 45 degree sweptback wings of aspect ratio 6: transonic-bump method

Description: Report presenting an aerodynamic investigation in the high-speed 7- by 10-foot tunnel to determine the effects of taper-in-thickness on the aerodynamic characteristics of wings with 35 and 45 degrees of sweepback, aspect ratio 6, and taper ratio 0.60. The wings were tested over a range of Mach numbers.
Date: July 10, 1951
Creator: Morrison, William D., Jr. & Fournier, Paul G.
Partner: UNT Libraries Government Documents Department

Contributions of wing, tail, and fuselage to the aerodynamic characteristics of a semispan model of a supersonic airplane configuration at transonic speeds from tests by the NACA wing-flow method

Description: Report presenting an investigation using the NACA wing-flow method at transonic speeds to determine the contributions of wing, tail, and fuselage to the aerodynamic characteristics of a semispan airplane model with a long slender fuselage and straight wing and tail of low aspect ratio with faired symmetrical double-wedge airfoil sections 4.6 percent of the chord in thickness. Results regarding the drag, pitching moment, downwash, and lift are provided.
Date: July 11, 1951
Creator: Silsby, Norman S. & McKay, James M.
Partner: UNT Libraries Government Documents Department

Flight investigation of the drag of round-nosed bodies of revolution at Mach numbers from 0.6 to 1.5 using rocket-propelled test vehicles

Description: From Summary: "Values of total drag coefficient were measured for four round-nosed bodies of revolution in free flight at Mach numbers from 0.6 to 1.5 and Reynolds numbers from 10 x 10(6) to 50 x 10(6). The bodies were designed by rounding off the sharp, fineness-ratio-3.56 nose of a previously tested configuration. The nose radii tested were 27.4, 38.7, 80.6, and 100 percent of the maximum body radius and corresponded to values of 0.075, 0.150, 0.650, and 1.000, respectively, for the ratio of nose-sphere frontal area to body frontal area. The body having least bluntness did not differ appreciably in drag from the pointed-nose body. The others showed marked increases in supersonic drag with increasing bluntness."
Date: July 25, 1951
Creator: Hart, Roger G.
Partner: UNT Libraries Government Documents Department

Theoretical investigation of an automatic control system with primary sensitivity to normal accelerations as used to control a supersonic canard missile configuration

Description: Report presenting a theoretical investigation of an automatic control system with primary sensitivity to normal accelerations as used to control a specific supersonic canard missile. The control system is made up of an integrating servomotor that receives a signal from an accelerometer that is sensitive to normal accelerations of the airframe that it is controlling. The acceleration control system appears to work well for obtaining longitudinal control, but works best when combined with a homing seeker or guidance system for controlling directional space.
Date: July 10, 1951
Creator: Seaberg, Ernest C. & Smith, Earl F.
Partner: UNT Libraries Government Documents Department

Altitude-test-chamber investigation of performance of a 28-inch ram-jet engine IV: effect of inlet-air temperature, combustion-chamber-inlet Mach number, and fuel volatility on combustion performance

Description: Report presenting testing of the effects of the following variables on combustion performance are determined: inlet-air temperature, combustion-chamber-inlet Mach number and pressure, and fuel density and volatility.
Date: July 27, 1951
Creator: Kahn, Robert W.; Nakanishi, Shigeo & Harp, James L., Jr.
Partner: UNT Libraries Government Documents Department

Compilation and review of effects of design parameters on ditching characteristics

Description: From Summary: "This paper supplements a previously published one on the effect of design parameters on ditching characteristics. The supplementary information is based on additional data available from both model tests and full-scale experience. In addition, summary tables compiled from the NACA model ditching investigations are presented."
Date: July 10, 1951
Creator: Fisher, Lloyd J. & Hoffman, Edward L.
Partner: UNT Libraries Government Documents Department

Free-flight investigation of the longitudinal stability and control of a rocket-propelled missile model having cruciform, triangular, interdigitated wings and tails

Description: Report presenting flight testing of a missile model with cruciform, triangular, interdigitated wings and tails to determine the longitudinal stability and control characteristics over a range of Mach numbers. Results regarding static stability and damping, control effectiveness, and control hinge moments are provided.
Date: July 10, 1951
Creator: Sandahl, Carl A. & Hall, James R.
Partner: UNT Libraries Government Documents Department

Velocity and temperature fields in circular jet expanding from choked nozzle into quiescent air

Description: The Mach number and temperature profiles in jets expanding from convergent and convergent-divergent nozzles are presented for several values of nozzle-exit pressure ratio. The effects of jet temperature, Reynolds number, and humidity on jet spreading are briefly evaluated. The results indicated that the downstream Mach number profiles for a heated jet are slightly narrower than those for a unheated jet, whereas the downstream temperature profiles were unaffected by nozzle temperature change, and that the effects of Reynolds number and humidity were negligible.
Date: July 12, 1951
Creator: Rousso, Morris D. & Kochendorfer, Fred D.
Partner: UNT Libraries Government Documents Department