Search Results

open access

The Effect of Curvature on the Transition From Laminar to Turbulent Boundary Layer

Description: Note presenting a discrepancy between the predicted and actual point of transition from laminar to turbulent boundary layer that had been found. This effect may be due to the comparatively small radius of curvature of the upper surface of the wing.
Date: September 1937
Creator: Clauser, Milton & Clauser, Francis
Partner: UNT Libraries Government Documents Department
open access

The Effect of Curvature on the Transition From Laminar to Turbulent Boundary Layer

Description: "In the flow over the upper surface of a wing, a discrepancy between the predicted and actual point of transition from laminar to turbulent boundary layer was found. This effect may be due to the comparatively small radius of curvature of the upper surface of the wing. Tests were undertaken to investigate this effect. As far as the authors know, the present investigation is the first to show that curvature has a pronounced effect on the transition of the boundary layer from the laminar to the t… more
Date: September 1937
Creator: Clauser, Milton & Clauser, Francis
Partner: UNT Libraries Government Documents Department
open access

Empirical corrections to the span load distribution at the tip

Description: An analysis of existing pressure-distribution data was made to determine the variation of the tip loading with wing plan form. A series of empirical tip corrections was derived that may be added to theoretical curves in certain cases to obtain a closer approach to the actual loading at the tip. The analysis indicated that the need for a tip correction decreases as either the aspect ratio or the wing taper is increased. In general, it may be said that, for wings of conventional aspect ratio, cor… more
Date: August 1937
Creator: Pearson, H. A.
Partner: UNT Libraries Government Documents Department
open access

Energy Loss, Velocity Distribution, and Temperature Distribution for a Baffled Cylinder Model

Description: A study has been made of the important principles involved in the operation of a baffle for an engine cylinder and shows that cooling can be improved by 20 percent by using a correctly designed baffle. Such a gain is as effective as a 65 percent increase in pressure drop across the standard baffle, which had a 1/4 inch clearance between baffle and fin tips.
Date: October 1937
Creator: Brevoort, Maurice J.
Partner: UNT Libraries Government Documents Department
open access

Energy Loss, Velocity Distribution, and Temperature Distribution for a Baffled Cylinder Model, Special Report

Description: Report discusses the important principles involved in the operation of a baffle for an engine cylinder and how using a correctly designed baffle can improve cooling. The baffle-exit radius and width and exit-duct length were found to be the most important parts of the baffle and a baffle that gave a relatively uniform temperature distribution was designed.
Date: April 1937
Creator: Brevoort, Maurice J.
Partner: UNT Libraries Government Documents Department
open access

The experimental and calculated characteristics of 22 tapered wings

Description: From Summary: "The experimental and calculated aerodynamic characteristics of 22 tapered wings are compared, using tests made in the variable-density wind tunnel. The wings had aspect ratios from 6 to 12 and taper ratios from 1:6:1 and 5:1. The compared characteristics are the pitching moment, the aerodynamic-center position, the lift-curve slope, the maximum lift coefficient, and the curves of drag. The method of obtaining the calculated values is based on the use of wing theory and experiment… more
Date: November 17, 1937
Creator: Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
open access

Experimental Apparatus for the Study of Propellers

Description: The apparatus consists of a universal balance with transmission at variable speeds from 300 to 5,000 rpm and a group directly coupled to the model for speeds of 5 to 30,000 revolutions. This new apparatus was also designed with a torsion meter for measuring the torque. Tests were conducted on the effect of the angle between the propeller axis and the wind direction. The results presented correspond to a first series of tests made without an interposed wing and in which the distance between the … more
Date: March 1937
Creator: Panetti, M.
Partner: UNT Libraries Government Documents Department
open access

Experimental investigation of the problem of surface roughness

Description: Based on the universal laws of turbulent velocity distribution at rough and smooth walls, there is in the present work presented a method that allows surface roughness tests and in particular, measurements on the roughness of ship surfaces to be carried out in a much simpler manner. The types of roughness investigated were in the form of flat, rough plates installed in a square-section rectangular channel, the other three walls always being smooth. Twenty-one plates of various roughness were in… more
Date: April 1937
Creator: Schlichting, H.
Partner: UNT Libraries Government Documents Department
open access

Experimental Investigation of Wind-Tunnel Interference on the Downwash Behind an Airfoil

Description: "The interference of the wind-tunnel boundaries on the downwash behind an airfoil has been experimentally investigated and the results have been compared with the available theoretical results for open-throat wind tunnels. As in previous studies, the simplified theoretical treatment that assumes the test section to be an infinite free jet has been shown to be satisfactory at the lifting line. The experimental results, however, show that this assumption may lead to erroneous conclusions regardin… more
Date: June 4, 1937
Creator: Silverstein, Abe & Katzoff, S.
Partner: UNT Libraries Government Documents Department
open access

Fairey "Battle" Medium Bomber Airplane (British): An All-Metal Low-Wing Cantilever Monoplane

Description: Circular presenting a description of the Fairey "Battle", which is the first stressed-skin aircraft they have constructed and is also an all-metal low-wing cantilever monoplane. Details of the fuselage, wings, skin, design, flaps, landing gear, characteristics, performance, drawings, and photographs are provided.
Date: November 1937
Partner: UNT Libraries Government Documents Department
open access

A Flight Comparison of Conventional Ailerons on a Rectangular Wing and of Conventional and Floating Wing-Tip Ailerons on a Tapered Wing

Description: Report presents the results of flight tests comparing the relative effectiveness of conventional ailerons of the same size on wings of rectangular and tapered plan forms made with a Fairchild 22 airplane. Information is included comparing conventional and floating wing-tip ailerons on a tapered wing. The results showed that the conventional ailerons were somewhat more effective on the tapered than on the rectangular wing. The difference, however, was so small as to be imperceptible to the pilot… more
Date: October 27, 1937
Creator: Soulé, H. A. & Gracey, W.
Partner: UNT Libraries Government Documents Department
open access

Flight tests of an airplane showing dependence of the maximum lift coefficient on the test conditions

Description: "Data are presented to show the extent to which the maximum lift coefficient and consequently the minimum speed of an airplane, determined by flight tests, may vary with test conditions. The data show that cl-max may vary as much as 14 percent, depending on the altitude and wing loading at which the tests were made, the position or motion of the propeller, and the rate at which the angle of attack is changing when the maximum lift coefficient is obtained. The variation of the maximum lift coeff… more
Date: November 1937
Creator: Soulé, H. A. & Hootman, James A.
Partner: UNT Libraries Government Documents Department
open access

Free spinning wind-tunnel tests of a low-wing monoplane with systematic wings and tails 2: Mass distributed along the fuselage

Description: Report presenting a study of eight wings and three tails covering a wide range of aerodynamic characteristics in 24 wing-tail combinations. Observations were made of the steady spin for four control settings and of recoveries for five control manipulations. The effect of wing shape, tail arrangement, control settings, relationships between spin characteristics, and comparison with results for basic loading are provided.
Date: December 1937
Creator: Seidman, Oscar & Neihouse, A. I.
Partner: UNT Libraries Government Documents Department
open access

Free-spinning wind-tunnel tests of a low-wing monoplane with systemic changes in wings and tails 1: Basic loading condition

Description: A series of tests was made at the National Advisory Committee for Aeronautics (NACA) free-spinning tunnel to determine the effect of systematic changes in wing and tail arrangement upon steady-spinning and recovery characteristics of a conventional low-wing monoplane model for a basic loading condition. Eight wings and three tails, covering a wide range of aerodynamic characteristics, were independently ballasted so as to be interchangeable with no change in mass distribution. For each of the 2… more
Date: August 1937
Creator: Seidman, Oscar & Neihouse, A. I.
Partner: UNT Libraries Government Documents Department
open access

Full scale span load distribution on a tapered wing with split flaps of various spans

Description: Pressure-distribution tests were conducted in the full-scale wind tunnel on a 2:1 tapered U.S.A. 45 airfoil equipped with 20 percent chord split trailing-edge flaps of various spans. A special installation was employed in the tests utilizing a half-span airfoil mounted vertically above a reflection plane. The airfoil has a constant chord center section and rounded tips and is tapered in thickness from 18 percent c at the root to 9 percent c at the tip. The aerodynamic characteristics, given by … more
Date: February 1937
Creator: Parsons, John F. & Silverstein, Abe
Partner: UNT Libraries Government Documents Department
open access

Full-Scale Tests of a New Type NACA Nose-Slot Cowling

Description: "An extended experimental study has been made in regard to the various refinements in the design of engine cowlings as related to the propeller-nacelle unit as a whole, under conditions corresponding to take-off, climb, and normal flight. The tests were all conducted at full scale in the 20-foot wind tunnel. This report presents the results of a novel type of engine cowling, characterized by the fact that the exit opening discharging the cooling air is not, as usual, located behind the engine b… more
Date: 1937
Creator: Theodorsen, Theodore; Brevoort, M. J.; Stickle, George W. & Gough, M. N.
Partner: UNT Libraries Government Documents Department
open access

Full-scale wind-tunnel and flight test of a Fairchild 22 airplane equipped with a Zap flap and Zap ailerons

Description: "A wing equipped with a Zap flap and Zap ailerons was tested on a Fairchild 22 airplane in the full-scale wind tunnel and in flight to determine the effect of the flaps and ailerons on the performance and the control characteristics of the airplane. The flaps were 0.30 of the wing chord and 0.83 of the wing span. Two sets of ailerons having equal areas but different proportions were tested, one set being 0.56 of the semispan and 0.18 of the chord and the other set being 0.46 of the semispan and… more
Date: March 1937
Creator: Dearborn, C. H. & Soulé, H. A.
Partner: UNT Libraries Government Documents Department
open access

Full-Scale Wind-Tunnel and Flight Tests of a Fairchild 22 Airplane Equipped With External-Airfoil Flaps

Description: "Wind-tunnel and flight tests have been made of a Fairchild 22 airplane equipped with a wing having external-airfoil flaps that also perform the function of ailerons. Lift, drag, and pitching-moment coefficients of the airplane with several flap settings, and the rolling- and yawing-moment coefficients with the flaps deflected as ailerons were measured in the full-scale tunnel with the horizontal tail surfaces and propeller removed. The effect of the flaps on the low speed and on the take-off a… more
Date: July 1937
Creator: Reed, Warren D. & Clay, William C.
Partner: UNT Libraries Government Documents Department
open access

Fuselage-drag tests in the variable-density wind tunnel: streamline bodies of revolution, fineness ratio of 5

Description: From Summary: "Results are presented of the drag tests of six bodies of revolution with systematically varying shapes and with a fineness ratio of 5. The forms were derived from source-sink distributions, and formulas are presented for the calculation of the pressure distribution of the forms. The tests were made in the N.A.C.A. variable-density tunnel over a range of values of Reynolds number from about 1,500,000 to 25,000,000. The results show that the bodies with the sharper noses and tails … more
Date: September 1937
Creator: Abbott, Ira H.
Partner: UNT Libraries Government Documents Department
open access

General Airplane Performance

Description: "Equations have been developed for the analysis of the performance of the ideal airplane, leading to an approximate physical interpretation of the performance problem. The basic sea-level airplane parameters have been generalized to altitude parameters and a new parameter has been introduced and physically interpreted. The performance analysis for actual airplanes has been obtained in terms of the equivalent ideal airplane in order that the charts developed for use in practical calculations wil… more
Date: June 1, 1937
Creator: Rockfeller, W. C.
Partner: UNT Libraries Government Documents Department
open access

The Ground Effect on Lifting Propellers

Description: In what follows an estimate will be made of the magnitude of the ground effect. For the two cases where the distance a of the propeller from the ground is very small, and very large, respectively, in comparison with the propeller radius r(sub o) the relations may be simply expressed. We consider first the effect of the ground, assuming that the thrust is held constant, as may be done by a suitable change in the propeller speed.
Date: August 1937
Creator: Betz, A.
Partner: UNT Libraries Government Documents Department
open access

Ground Effect - Theory and Practice

Description: The conclusion of a previous article by Pistolesi is that the increment of lift due to ground effect is largely attributable to the effect of induction of the free vortices, and is practically equivalent to a virtual increase in aspect ratio. The ground clearance was of the order of magnitude comparable to the wing chord. New reports by Le Seur and Datwyler treat the case of minimum distance from the ground and is confined to the plane problem only. The author briefly reviews these reports and … more
Date: June 1937
Creator: Pistolesi, E.
Partner: UNT Libraries Government Documents Department
open access

The Gyroplane: Its Principles and Its Possibilities

Description: This report begins by indicating several simple principles concerning the velocity distribution over the blades of a lifting propeller of diameter D, revolving at n revolutions per second, and animated by a horizontal movement of translation at speed V. The calculation, compared with the test data, has shown that the aerodynamic action of the air on the blades depends almost only on the velocity components in a plane at right angles to the blade span. A history of gyroplane and gyrocopter devel… more
Date: January 1937
Creator: Breguet, Louis
Partner: UNT Libraries Government Documents Department
Back to Top of Screen