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Tests of large airfoils in the propeller research tunnel, including two with corrugated surfaces

Description: This report gives the results of the tests of seven 2 by 12 foot airfoils (Clark Y, smooth and corrugated, Gottingen 398, N.A.C.A. M-6, and N.A.C.A. 84). The tests were made in the propeller research tunnel of the National Advisory Committee for Aeronautics at Reynolds numbers up to 2,000,000. The Clark Y airfoil was tested with three degrees of surface smoothness. Corrugating the surface causes a flattening of the lift curve at the burble point and an increase in drag at small flying angles.
Date: May 24, 1929
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department

Interferometric observation of flow about an isentropic (reverse Prandtl-Meyer streamline) compression wedge at Mach 3.0

Description: Report presenting an interferometric study of the flow over a two-dimensional isentropic compression surface at a Mach number of 3.0. The flow field was essentially that of a strong-branch-shock configuration resulting from a surface flow turning that corresponded to an empirical limiting value of free-stream normal-shock pressure rise.
Date: March 28, 1955
Creator: Connors, James F.; Woollett, Richard R. & Blue, Robert E.
Partner: UNT Libraries Government Documents Department

Characteristics of thin triangular wings with constant-chord partial-span control surfaces at supersonic speeds

Description: Report presenting a theoretical analysis of the characteristics of constant-chord partial-span control surfaces on thin triangular wings at supersonic speeds by use of methods based on the linearized theory for supersonic flow. Two cases were treated with the analysis. Results regarding lift coefficient, rolling-moment coefficient, and hinge-moment coefficient due to flap deflection, hinge-moment coefficient due to angle of attack, and the pitching-moment coefficient due to flap lift.
Date: July 1948
Creator: Tucker, Warren A. & Nelson, Robert L.
Partner: UNT Libraries Government Documents Department

Tank tests of flat and v-bottom planning surfaces

Description: "Four planing surfaces, all having beams of 16 inches and lengths of 60 inches but varying in dead rise by 10 degrees increments from 0 degrees to 30 degrees, were tested in the N.A.C.A. tank. The results cover a wide range of speed, loads, and trim angles, and are applicable to a variety of problems encountered in the design of seaplanes. The data are analyzed to determine the characteristics of each surface at the trim angle giving minimum resistance for all the speed and loads tested. A planing coefficient intended to facilitate the application of the results to design work is developed and curves of resistance, wetted length, and center of pressure are plotted against this coefficient" (p. 1).
Date: November 1934
Creator: Shoemaker, James M.
Partner: UNT Libraries Government Documents Department

Preliminary investigation of self-excited vibrations of single planing surfaces

Description: "A preliminary investigation was made of self-excited vibrations of single planing surfaces. A self-excited oscillation requiring freedom in rise but not in trim occurred with high aspect ratio (order of 10) of the wetted portion. This vibration could be controlled most successfully by methods (such as the use of dead rise) which limited the wetted aspect ratio" (p. 1).
Date: June 1956
Creator: Mottard, Elmo J.
Partner: UNT Libraries Government Documents Department

Effect of shallow water on the hydrodynamic characteristics of a flat-bottom planing surface

Description: Report presenting an investigation on the tank no. 2 monorail to determine the effect of shallow water on the hydrodynamic characteristics of a flat-bottom planing surface. Values of lift, drag, and trimming moment at a constant speed over a range of trim, wetted lengths, and clearances between the model and a false bottom in the tank.
Date: April 1956
Creator: Christopher, Kenneth W.
Partner: UNT Libraries Government Documents Department

A method for calculation of hydrodynamic lift for submerged and planing rectangular lifting surfaces

Description: A method is presented for the calculation of lift coefficients for rectangular lifting surfaces of aspect ratios from 0.125 to 10 operating at finite depths beneath the water surface, including the zero depth or planing condition. Theoretical values are compared with experimental values obtained at various depths of submergence with lifting surfaces of aspect ratios from 0.125 to 10. The method can also be applied to hydrofoils with dihedral. Lift coefficients computed by this method are in good agreement with existing experimental data for aspect ratios from 0.125 to 10 and dihedral angles up to 10 degrees.
Date: January 1958
Creator: Wadlin, Kenneth L. & Christopher, Kenneth W.
Partner: UNT Libraries Government Documents Department

Low-speed static lateral and rolling stability characteristics of a series of configuration composed of intersecting triangular plan-form surfaces

Description: Report presenting the static lateral and rolling stability derivatives of a series of cruciform, inverted T-, V-, and Y-configurations composed of low-aspect-ratio triangular surfaces at low speed in the rolling-flow test section. Comparisons have been made to indicate the extent of agreement between experiment and existing theory. Results regarding sideslip characteristics and steady rolling characteristics are provided.
Date: October 1955
Creator: Thomas, David F., Jr.
Partner: UNT Libraries Government Documents Department

The planing characteristics of a surface having a basic angle of dead rise of 40 degrees and horizontal chine flare

Description: Report presenting an experimental investigation with a surface with a dead rise angle of 40 degrees and horizontal chine flare to determine the effects of increasing the angle of dead rise on the planing characteristics of horizontally flared prismatic surfaces. Wetted length, resistance, center-of-pressure location, and draft were determined for a range of speed coefficients and trims. Planing characteristics for a given trim were found to depend mainly on lift coefficient.
Date: December 1952
Creator: Blanchard, Ulysse J.
Partner: UNT Libraries Government Documents Department

Experiments with planing surfaces

Description: A previous report discusses the experimental program of a systematic exploration of all questions connected with the planing problem as well as the first fundamental results of the investigation of a flat planing surface. The present report is limited to the conversion of the model test data to full scale.
Date: March 1934
Creator: Sottorf, W.
Partner: UNT Libraries Government Documents Department

Experiments with planing surfaces

Description: Experiments with planing surfaces are fundamental, hydrodynamic researches for the purpose of obtaining the most favorable forms for planing boats, flying boats, and seaplane floats, with respect to water resistance and seaworthiness.
Date: March 1932
Creator: Sottorf, W.
Partner: UNT Libraries Government Documents Department

Scale effect of model in seaplane-float investigations

Description: For the purpose of solving all the problems involved, an investigation was made with flat, rectangular planing surfaces. The investigation of a flat, rectangular planing surface, which can be considered as the portion of a flat float bottom lying in front of the step, has the advantage that the frictional resistance can be determined directly from the test results. Normal and tangential forces act on the lower side of the planing surface towed through still water, while the upper side and the lateral edges are under constant atmospheric pressure.
Date: April 1933
Creator: Sottorf, W.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Thin Empirical Profiles and Their Application to the Tail Surfaces and Ailerons of Airplanes

Description: From Introduction: "The increasing use of airplane wings equipped with ailerons and the importance of knowing the aerodynamic characteristics of tail units (empennages) provided with movable parts (rudders and elevators) impart some interest to the so-called "empirical profiles." For this purpose we thought best to employ the method proposed by Munk for the approximate theoretical study of thin, slightly curved profiles, assimilable, from an aerodynamic view-point, to their mean camber line."
Date: December 1928
Creator: Toussaint, A. & Carafoli, E.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Horizontal Tail Surfaces

Description: From Summary: "Collected data are presented on the aerodynamic characteristics of 17 horizontal tail surfaces including several with balanced elevators and two with end plates. Curves are given for coefficients of normal force, drag, and elevator hinge moment. A limited analysis of the results has been made. The normal-force coefficients are in better agreement with the lifting-surface theory of Prandtl and Blenk for airfoils of low aspect ratio than with the usual lifting-line theory. Only partial agreement exists between the elevator hinge-moment coefficients and those predicted by Glauert's thin-airfoil theory."
Date: 1940
Creator: Silverstein, Abe & Katzoff, S.
Partner: UNT Libraries Government Documents Department

Preliminary Tank Tests With Planing-Tail Seaplane Hulls

Description: Report presenting testing made with simplified models of two types of hulls that differ considerably from conventional types. Both have a single main planing surface that is combined with after-planing surfaces placed directly below the aerodynamic tail surfaces. Results regarding an investigation of twin planing tails, a single-planing tail, and potentialities indicated by tests are provided.
Date: June 1943
Creator: Dawson, John R. & Waldin, Kenneth L.
Partner: UNT Libraries Government Documents Department

Changes Found on Run-in and Scuffed Surfaces of Steel Chrome Plate, and Cast Iron

Description: Note presenting a study of run-in and scuffed steel, chrome-plate, and cast-iron surfaces. X-ray and electronic diffraction techniques, micro-hardness determinations, and microscopy were used. The surface changes varied and wer efound to include three classes: chemical reaction, hardening, and crystallite-size alteration.
Date: October 1947
Creator: Good, J. N. & Godfrey, Douglas
Partner: UNT Libraries Government Documents Department

Planing-Surface Tests at Large Froude Numbers - Airfoil Comparison

Description: "The take-off capacity of a flying boat depends upon the design of the hull bottom ahead as well as aft of the step. Systematic tests - largely made by industry itself - had proved the benefit accruing from a well designed hull bottom long before theoretical insight into the flow phenomena involved had been obtained. The theoretical framing of the problem was beset with serious difficulties and, though restricted to the processes within range of the planing bottom ahead of the step, the solutions do not yet afford a comprehensive survey" (p. 1).
Date: February 1938
Creator: Sambraus, A.
Partner: UNT Libraries Government Documents Department

Fairing Compositions for Aircraft Surfaces

Description: Note presenting fairing compositions applied to aircraft surfaces, welds and junctions of metal plates, and rivet depressions to improve the aerodynamic efficiency of the airplane at high speeds. A method is described for formulating fairing compositions which have, within limits, desired coefficients of thermal expansion. Results regarding water-immersion tests, thermal expansion and softening temperature, temperature-cycle tests, and density are provided.
Date: November 1944
Creator: Turner, Philip S.; Doran, Jewel & Reinhart, Frank W.
Partner: UNT Libraries Government Documents Department

High-Speed Hydrodynamic Characteristics of a Flat Plate and 20 Degrees Dead-Rise Surface in Unsymmetrical Planing Conditions

Description: Note presenting the results of an investigation made to obtain the wetted areas, three components of planing forces, and the three components of moments acting on a 0 degree and a 20 degree dead-rise surface in high-speed, unsymmetrical planing conditions. The collected test data are presented in summary plots which are readily applicable for use in determining the lift, drag, side force, pitching moment, rolling moment, and yawing moment.
Date: June 1958
Creator: Savitsky, Daniel; Prowse, R. E. & Lueders, D. H.
Partner: UNT Libraries Government Documents Department

Tests at Mach Number 1.62 of a Series of Missile Configurations Having Tandem Cruciform Lifting Surfaces

Description: Memorandum presenting an investigation at a Mach number of 1.62 in the 9-inch supersonic tunnel of a series of missile configurations with tandem lifting surfaces of low aspect ratio and of nearly equal span. Some of the variables investigated were interdigitation angle, wing and tail plan form, and longitudinal location of wing with respect to tail. Lift, drag, and pitching-moment data are presented, together with center-of-pressure locations and tail-lift efficiency factors.
Date: January 11, 1952
Creator: Grigsby, Carl E.
Partner: UNT Libraries Government Documents Department