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Operational treatment of the nonuniform-lift theory in airplane dynamics

Description: "The method of operators is used in the application of nonuniform-lift theory to problems of airplane dynamics. The method is adapted to the determination of the lift under prescribed conditions of motion or to the determination of the motions with prescribed disturbing forces" (p. 1).
Date: October 1938
Creator: Jones, Robert T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tank tests of a model of one hull of the Savoia S-55-X flying boat - N.A.C.A. Model 46

Description: A model of one of the twin hulls of the Italian Savoia S-55-X flying boat (N.A.C.A. Model 46) was tested in the N.A.C.A. tank according to the general method. The data obtained from these tests cover a broad range of speeds, loads, and trims and are given in nondimensional form to facilitate their use in applying this form of hull to any other flying boat or comparing it's performance with the performance of any other hulls. The results show that the resistance characteristics at best trim of t… more
Date: February 1938
Creator: Allison, John M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic and aerodynamic tests of models of flying-boat hulls designed flow aerodynamic drag - NACA models 74, 74-A, and 75

Description: The present tests illustrate how the aerodynamic drag of a flying boat hull may be reduced by following closely the form of a low drag aerodynamic body and the manner in which the extent of the aerodynamic refinement is limited by poorer hydrodynamic performance. This limit is not sharply defined but is first evidenced by an abnormal flow of water over certain parts of the form accompanied by a sharp increase in resistance. In the case of models 74-A and 75, the resistance (sticking) occurs onl… more
Date: October 1938
Creator: Truscott, Starr; Parkinson, J. B.; Ebert, John W., Jr. & Valentine, E. Floyd
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The drag of inflatable rubber de-icers

Description: Force tests on rubber de-icer models of several different profiles, at approximately one-third full scale, been carried out in the NACA 8-foot high speed wind tunnel. The conventional de-icer installation, deflated, added about 15 percent to the smooth-wing drag and, inflated, added about 100 percent. An improved installation with flash attaching strips added about 10 percent, deflated. The bulging, or ballooning, of de-icers from the wing surface is described and some remedies are discussed.
Date: October 1938
Creator: Robinson, Russell G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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N.A.C.A. Stall-Warning Indicator

Description: "The stall-warning indicator employs a total-head tube located close to the wing surface in a region wherein local stalling occurs before the main portion of the wing stalls. The artificial production of a localized stalled region is accomplished by means of a sharp leading edge extending a few inches along the span. An abrupt drop in the total pressure relative to a static reference taken at some convenient point occurs at the stall in this region" (p. 1).
Date: October 1938
Creator: Thompson, F. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The estimation of the rate of change of yawing moment with sideslip

Description: "Wind-tunnel data are presented on the rate of change of yawing moment with sideslip for tests of 9 complete airplane models, 20 fuselage shapes, and 3 wing models with various combinations of dihedral, sweepback, and twist. The data were collected during a survey of existing information, which was made to find a reliable method of computing the yawing moment due to sideslip. Important errors common to methods of computation used at present appear to be due to large interference effects, the in… more
Date: February 1938
Creator: Imlay, Frederick H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A method of rapidly estimating the position of the laminar separation point

Description: From Summary :"A method is described of rapidly estimating the position of the laminar separation point from the given pressure distribution along a body; the method is applicable to a fairly wide variety of cases. The laminar separation point is found by the von Karman-Millikan method for a series of velocity distributions along a flat plate, which consist of a region of uniform velocity followed by a region of uniform decreased velocity. It is shown that such a velocity distribution can frequ… more
Date: October 1938
Creator: von Doenhoff, Albert E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wind-Tunnel Tests of a 2-Engine Airplane Model as a Preliminary Study of Flight Conditions Arising on the Failure of the Engine

Description: "Wind tunnel tests of a 15-foot-span model of a two-engine low wing transport airplane were made as a preliminary study of the emergency arising from the failure of one engine in flight. Two methods of reducing the initial yawing moment resulting from the failure of one engine were investigated and the equilibrium conditions were explored for two basic modes on one engine, one with zero angle of sideslip and the other with several degrees of sideslip. The added drag resulting from the unsymmetr… more
Date: April 1938
Creator: Hartman, Edwin P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Engine performance and knock rating of fuels for high-output aircraft engines

Description: From Summary: "Data are presented to show the effects of inlet-air pressure, inlet-air temperature, and compression ratio on the maximum permissible performance obtained on a single-cylinder test engine with aircraft-engine fuels varying from a fuel of 87 octane number to one 100 octane number plus 1 ml of tetraethyl lead per gallon. The data were obtained on a 5-inch by 5.75-inch liquid-cooled engine operating at 2,500 r.p.m. The compression ratio was varied from 6.50 to 8.75. The inlet-air te… more
Date: April 1938
Creator: Rothrock, A. M. & Biermann, Arnold E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interference of Wing and Fuselage From Tests of 17 Combinations in the N.A.C.A. Variable-Density Tunnel Combination With Special Junctures

Description: "As part of the wing-fuselage interference program in progress in the NACA variable-density wind tunnel, a method of eliminating the interference bubble associated with critical mid wing combinations was investigated. The interference bubble of the critical mid wing combination was shown to respond to modification at the nose of the juncture and to be entirely suppressed with little or no adverse effect on the high-speed drag by special leading edge fillets" (p. 1).
Date: March 1938
Creator: Sherman, Albert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interference of Wing and Fuselage From Tests of Eight Combinations in the N.A.C.A. Variable-Density Tunnel Combinations With Tapered Fillets and Straight-Side Junctures

Description: "The round fuselage of an unfilleted low-wing combination was modified to incorporate straight-side junctures. The resulting combination, with or without horizontal tail surfaces, had practically the same aerodynamic characteristics as the corresponding round-fuselage tapered-fillet combination" (p. 1).
Date: March 1938
Creator: Sherman, Albert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A study of flying-boat take-off

Description: It is shown that the normal resistance curve for a flying boat may be approximated by two straight lines. The equations for take-off distance and time, derived from this approximation, are applied to a series of flying boats and the resulting factors are plotted in non dimensional form in a series of charts. Take-off performances from the charts are shown to be in good agreement with step-by-step integrations. Some applications of the charts to the solution of general design problems are includ… more
Date: April 1938
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Flight and wind-tunnel tests of an XBM-1 dive bomber

Description: From Summary: "Results are given of pressure-distribution measurements made in flight over the right wing cellule and the right half of the horizontal tail surfaces of a dive-bombing biplane. Simultaneous measurements were also taken of the air speed, control-surface positions, control forces, and normal accelerations during various abrupt maneuvers in vertical plane. These maneuvers consisted of push-downs and pull-ups from level flight, dives and dive pull-ups from inverted flight. Besides th… more
Date: April 1938
Creator: Donely, Philip & Pearson, Henry A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tank Tests to Show the Effect Rivet Heads on the Water Performance of a Seaplane-Float

Description: "A 1/3.5 full-sized model of a seaplane float constructed from lines supplied by the Bureau of Aeronautics, Navy Department, was tested first with smooth painted bottom surfaces and then with round-head rivets, plate laps, and keel plates fitted to simulate the actual bottom of a metal float. A percentage increase in water resistance caused by the added roughness was found to be from 5 to 20 percent at the hump speed and from 15 to 40 percent at high speeds. The effect of the roughness of the a… more
Date: July 1938
Creator: Parkinson, J. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Generalized Analysis of Experimental Observations in Problems of Elastic Stability

Description: "A generalized method of analyzing experimental observations in problems of elastic stability is presented in which the initial readings of load and deflection may be taken at any load less the critical load. The analysis is an extension of a method published by Southwell in 1932, in which it was assumed that the initial readings are taken at zero load" (p. 1).
Date: July 1938
Creator: Lundquist, Eugene E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Aerodynamic Drag of Five Models of Side Floats N.A.C.A. Models 51-E, 51-F, 51-G, 51-H, 51-J

Description: "The drag of five models of side floats was measured in the N.A.C.A. 7- by 10-foot wind tunnel. The most promising method of reducing the drag of floats indicated by these tests is lowering the angle at which the floats are rigged. The addition of a step to a float does not always increase the drag in the flying range, floats with steps sometimes having lower drag than similar floats without steps" (p. 1).
Date: December 1938
Creator: House, R. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A general tank test of a model of the hull of the Pem-1 flying boat including a special working chart for the determination of hull performance

Description: The results of a general tank test of a 1/6 full-size model of the hull of the P3M-1 flying boat (N.A.C.A. model 18) are given in non-dimensional form. In addition to the usual curves, the results are presented in a new form that makes it possible to apply them more conveniently than in the forms previously used. The resistance was compared with that of N.A.C.A. models 11-C and 26(Sikorsky S-40) and was found to be generally less than the resistance of either.
Date: December 1938
Creator: Dawson, John R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wind-Tunnel of Three Lateral-Control Devices in Combination With a Full-Span Slotted Flap on an NACA 23012 Airfoil

Description: "A large-chord NACA 23012 airfoil was tested. The airfoil extended completely across the test section, and two-dimensional flow was approximated. The model was fitted with a full-span slotted flap having a chord 25.66 percent of the airfoil chord. The ailerons investigated extended over the entire span and each had a chord 10 percent of the airfoil chord" (p. 1).
Date: August 1938
Creator: Wenzinger, Carl J. & Bamber, Millard J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fuel Consumption of a Carburetor Engine at Various Speeds and Torques

Description: "An investigation was conducted to obtain fuel-consumption curves for a single-cylinder engine with a Wright 1820-G and Pratt & Whitney 1340-H cylinder at varying speeds, manifold pressures, and air-fuel ratios. The 1340- H cylinder was tested at speeds from 1,200 to 2,400 r.p.m. and at manifold pressures from 21 to 38 inches of mercury absolute. Less than extensive tests were made of the 1820-G cylinder. The results of the tests showed that the minimum brake fuel consumption was obtained when … more
Date: June 1938
Creator: Schey, Oscar W. & Clark, J. Denny
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Principles involved in the cooling of a finned and baffled cylinder

Description: An analysis of the cooling problems for a finned cylinder is made on the basis of the known fundamental principles of heat transfer from pipes. Experimental results that support the analysis are presented. The results of previous investigations on the problem are evaluated on the basis of the analysis and the results. An illustration of the application of these principles to a specific problem is included.
Date: June 1938
Creator: Brevoort, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrodynamic and aerodynamic tests of models of floats for single-float seaplanes NACA models 41-D, 41-E, 61-A, 73, and 73-A

Description: Tests were made in the NACA tank and in the NACA 7 by 10 foot wind tunnel on two models of transverse step floats and three models of pointed step floats considered to be suitable for use with single float seaplanes. The object of the program was the reduction of water resistance and spray of single float seaplanes without reducing the angle of dead rise believed to be necessary for the satisfactory absorption of the shock loads. The results indicated that all the models have less resistance an… more
Date: July 1938
Creator: Parkinson, J. B. & House, R. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Noise From Propellers With Symmetrical Sections at Zero Blade Angle, 2

Description: "In a previous paper (Technical Note No. 605), a theory was developed that required an empirical relation to calculate sound pressures for the higher harmonics. Further investigation indicated that the modified theory agrees with experiment and that the empirical relation was due to an interference phenomenon peculiar to the test arrangement used. Comparison is made between the test results for a two-blade arrangement and the theory" (p. 1).
Date: December 1938
Creator: Deming, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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