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Determination of the characteristics of tapered wings

Description: This report presents tables and charts for use in determining the characteristics of tapered wings. Theoretical factors are given from which the following characteristics of tapered wings may be found: the span lift distribution, the induced-angle-of attack distribution, the lift-curve slope, the angle of zero lift, the induced drag, the aerodynamic-center position, and the pitching moment about the aerodynamic center.
Date: May 1, 1936
Creator: Anderson, Raymond F.

NACA investigation of fuel performance in piston-type engines

Description: This report is a compilation of many of the pertinent research data acquired by the National Advisory Committee for Aeronautics on fuel performance in piston engines. The original data for this compilation are contained in many separate NACA reports which have in the present report been assembled in logical chapters that summarize the main conclusions of the various investigations. Complete details of each investigation are not included in this summary; however, such details may be found, in the original reports cited at the end of each chapter.
Date: May 15, 1951
Creator: Barnett, Henry C.

The N.A.C.A. photographic apparatus for studying fuel sprays from oil engine injection valves and test results from several researches

Description: "Apparatus for recording photographically the start, growth, and cut-off of oil sprays from injection valves has been developed at the Langley Memorial Aeronautical Laboratory. The apparatus consists of a high-tension transformer by means of which a bank of condensers is charged to a high voltage. The controlled discharge of these condensers in sequence, at a rate of several thousand per second, produces electric sparks of sufficient intensity to illuminate the moving spray for photographing. The sprays are injected from various types of valves into a chamber containing gases at pressures up to 600 pounds per square inch" (p. 361).
Date: May 25, 1927
Creator: Beardsley, Edward G.

Photographic investigation of combustion in a two-dimensional transparent rocket engine

Description: Motion pictures at camera speeds up to 3000 frames per second were taken of the combustion of liquid oxygen and gasoline in a 100-pound thrust rocket engine. The effect of seven methods of propellant injection on the uniformity of combustion was investigated. The flame front was generally found to extend to the injector faces and all the injection systems showed considerable nonuniformity of combustion. Pressure vibration records indicated combustion vibrations that corresponded to resonant-chamber frequencies.
Date: May 22, 1953
Creator: Bellman, Donald R.; Humphrey, Jack C. & Male, Theodore

An empirically derived basis for calculating the area, rate, and distribution of water-drop impingement on airfoils

Description: From Summary: "An empirically derived basis for predicting the area, rate, and distribution of water-drop impingement on airfoils of arbitrary section is presented. The concepts involved represent an initial step toward the development of a calculation technique which is generally applicable to the design of thermal ice-prevention equipment for airplane wing and tail surfaces. It is shown that sufficiently accurate estimates, for the purpose of heated-wing design, can be obtained by a few numerical computations once the velocity distribution over the airfoil has been determined. The calculation technique presented is based on results of extensive water-drop trajectory computations for five airfoil cases which consisted of 15-percent-thick airfoils encompassing a moderate lift-coefficient range."
Date: May 8, 1951
Creator: Bergrun, Norman R.

Maneuverability investigation of the F6C-3 airplane with special flight instruments

Description: "This investigation was made for the purpose of obtaining information on the maneuverability of the F6C-3 airplane. It is the first of a series of similar investigations to be conducted on a number of military airplanes for the purpose of comparing the abilities of these airplanes to maneuver, and also to establish a fund of quantitative data which may be used in formulating standards of comparison for rating the maneuverability of any airplane. A large part of this initial investigation was necessarily devoted to the development and trial of methods suitable for use in subsequent investigations of this nature" (p. 117).
Date: May 23, 1930
Creator: Dearborn, C. H. & Kirschbaum, H. W.

Investigation of the NACA 4-(5)(08)-03 and NACA 4-(10)(08)-03 two-blade propellers at forward Mach numbers to 0.725 to determine the effects of camber and compressibility on performance

Description: As part of a general investigation of propellers at high forward speeds, tests of two-blade propellers having the NACA 4-(5)(08)-03 and NACA 4-(10)(08)-03 blade designs were made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 60 degrees for forward Mach numbers from 0.165 to 0.70 to determine the effect of camber and compressibility on propeller characteristics. Results previously reported for similar tests of a two-blade propeller having the NACA 4-(3)(08)-03 blade design are included for comparison.
Date: May 7, 1945
Creator: Delano, James B.

Calculated spanwise lift distributions, influence functions, and influence coefficients for unswept wings in subsonic flow

Description: Spanwise lift distributions have been calculated for nineteen unswept wings with various aspect ratios and taper ratios and with a variety of angle-of-attack or twist distributions, including flap and aileron deflections, by means of the Weissinger method with eight control points on the semispan. Also calculated were aerodynamic influence coefficients which pertain to a certain definite set of stations along the span, and several methods are presented for calculating aerodynamic influence functions and coefficients for stations other than those stipulated. The information presented in this report can be used in the analysis of untwisted wings or wings with known twist distributions, as well as in aeroelastic calculations involving initially unknown twist distributions.
Date: May 5, 1953
Creator: Diederich, Franklin W. & Zlotnick, Martin

Relative loading on biplane wings of unequal chords

Description: It is shown that the lift distribution for a biplane with unequal chords may be calculated by the method developed in NACA Technical report no. 458 if corrections are made for the inequality in chord lengths. The method is applied to four cases in which the upper chord was greater than the lower and good agreement is obtained between observed and calculated lift coefficients.
Date: May 18, 1934
Creator: Diehl, Walter S.

Computation of the two-dimensional flow in a laminar boundary layer

Description: A comparison is made of the boundary-layer flow computed by the approximate method developed by K. Pohlhausen with the exact solutions which have been published for several special cases. A modification of Pohlhausen's method has been developed which extends the range of application at the expense of some decrease in the accuracy of the approximations.
Date: May 1934
Creator: Dryden, Hugh L.

The effect of area aspect ratio on the yawing moments of rudders at large angles of pitch on three fuselages

Description: This reports presents the results of measurements made of yawing moments produced by rudder displacement for seven rudders mounted on each of three fuselages at angles of pitch of 0 degree, 8 degrees, 12 degrees, 20 degrees, 30 degrees and 40 degrees. The dimensions of the rudders were selected to cover the range of areas and aspect ratios commonly used, while the ratios of rudder area to fin area and of rudder chord to fin chord were kept approximately constant. An important result of the measurements is to show that increased aspect ratio gives increased yawing moments for a given area, provided the maximum rudder displacement does not exceed 25 degrees. If large rudder displacements are used, the effect of aspect ratio is not so great.
Date: May 16, 1932
Creator: Dryden, Hugh L. & Monish, B. H.

Experiments to Determine Neighborhood Reactions to Light Airplanes With and Without External Noise Reduction

Description: "The work reported was part of a program of experimentation with external noise reduction on light airplanes. This particular study was in effect a byproduct survey conceived to utilize already available equipment and personnel to further the findings of the original research and to determine reactions in populated neighborhoods to light aircraft with and without noise-reduction equipment. The findings indicate that at the 10 sites within and about metropolitan Boston the degree of noise reduction previously found to be aerodynamically and structurally feasible did eliminate substantially all neighborhood objections to noise per se" (p. 1155).
Date: May 5, 1950
Creator: Elwell, Fred S.

A wind-tunnel investigation of the aerodynamic characteristics of a full-scale supersonic-type three-blade propeller at Mach numbers to 0.96

Description: From Summary: "An investigation of the characteristics of a full-scale supersonic-type propeller has been made in the Langley 16-foot transonic tunnel with the 6000-horsepower propeller dynamometer. The tests covered a range of blade angles from 20.2 degrees to 60.2 degrees at forward Mach numbers up to 0.96. The results showed that envelope efficiency at an advance ratio of 2.8 decreased from 86 percent to 72 percent when the forward Mach number was increased from 0.70 to 0.96."
Date: May 18, 1953
Creator: Evans, Albert J. & Liner, George

Flight Studies of the Horizontal-Tail Loads Experienced by a Fighter Airplane in Abrupt Maneuvers

Description: Field measurements were made on a fighter airplane to determine the approximate magnitude of the horizontal tail loads in accelerated flight. In these flight measurements, pressures at a few points were used as an index of the tail loads by correlating these pressures with complete pressure-distribution data obtained in the NACA full-scale tunnel. In addition, strain gages and motion pictures of tail deflections were used to explore the general nature and order of magnitude of fluctuating tail loads in accelerated stalls.
Date: May 8, 1944
Creator: Flight Research Maneuvers Section

A summary and analysis of the low-speed longitudinal characteristics of swept wings at high Reynolds number

Description: An analysis of the longitudinal characteristics of swept wings which is based on available large-scale low-speed data and supplemented with low-scale data when feasible is presented. The emphasis has been placed on the differentiation of the characteristics by a differentiation between the basic flow phenomenon involved. Insofar as possible all large-scale data available as of August 15, 1951 have been summarized in tabular form for ready reference.
Date: May 14, 1952
Creator: Furlong, G. Chester & McHugh, James G.

Propulsion of a flapping and oscillating airfoil

Description: Formulas are given for the propelling or drag force experience in a uniform air stream by an airfoil or an airfoil-aileron combination, oscillating in any of three degrees of freedom; vertical flapping, torsional oscillations about a fixed axis parallel to the span, and angular oscillations of the aileron about a hinge.
Date: May 4, 1936
Creator: Garrick, I. E.

Flutter and oscillating air-force calculations for an airfoil in two-dimensional supersonic flow

Description: A connected account is given of the Possio theory of non-stationary flow for small disturbances in a two-dimensional supersonic flow and of its application to the determination of the aerodynamic forces on an oscillating airfoil. Further application is made to the problem of wing flutter in the degrees of freedom - torsion, bending, and aileron rotations. Numerical tables for flutter calculations are provided for various values of the Mach number greater than unity. Results for bending-torsion wing flutter are shown in figures and are discussed. The static instabilities of divergence and aileron reversal are examined as is a one-degree-of-freedom case of torsional oscillatory instability.
Date: May 29, 1946
Creator: Garrick, I. E. & Rubinow, S. I.

Effect of orifice length-diameter ratio on fuel sprays for compression-ignition engines

Description: "Experimental results on the effect of the length-diameter ratio of the orifice on the spray characteristics, together with a brief analysis of the factors affecting these characteristics, are presented in this report. The length-diameter ratios tested ranged from 0.5 to 10; the orifice diameters from 0.008 to 0.040 inch; and the injection pressures from 2,000 to 8,000 pounds per square inch. The density of the air into which the fuel was discharged was varied from 0.38 to 1.35 pounds per cubic foot" (p. 79).
Date: May 27, 1931
Creator: Gelalles, A. G.

Rates of fuel discharge as affected by the design of fuel-injection systems for internal-combustion engines

Description: Using the method of weighing fuel collected in a receiver during a definite interval of the injection period, rates of discharge were determined, and the effects noted, when various changes were made in a fuel-injection system. The injection system consisted primarily of a by-pass controlled fuel pump and an automatic injection valve. The variables of the system studied were the pump speed, pump-throttle setting, discharge-orifice diameter, injection-valve opening and closing pressures, and injection-tube length and diameter.
Date: May 15, 1932
Creator: Gelalles, A. G. & Marsh, E. T.

The Variation in Engine Power With Altitude Determined From Measurements in Flight With a Hub Dynamometer

Description: "The rate of change in power of aircraft engines with altitude has been the subject of considerable discussion. Only a small amount of data from direct measurements of the power delivered by airplane engines during flight, however, has been published. This report presents the results of direct measurements of the power delivered by a Liberty 12 airplane engine taken with a hub dynamometer at standard altitudes from zero to 13,000 feet. Six flights were made with the engine installed in a modified DH-4 airplane" (p. 323).
Date: May 7, 1928
Creator: Gove, W. D.