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Hydrodynamic and Aerodynamic Tests of Four Models of Outboard Floats: (N.A.C.A. Models 51-A, 51-B, 51-C, and 51-D)

Description: Four models of outboard floats (N.A.C.A. models 51-A, 51-B, 51-C, and 51-D) were tested in the N.A.C.A. tank to determine their hydrodynamic characteristics and in the 20-foot wind tunnel to determine their aerodynamic drag. The results of the tests, together with comparisons of them, are presented in the form of charts. From the comparisons, the order of merit of the models is estimated for each factor considered. The best compromise between the various factors seems to be given by model 51-D.… more
Date: December 1938
Creator: Dawson, John R. & Hartman, Edwin P.
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 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
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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 tests in the N.A.C.A. tank of a model of the hull of the Short Calcutta flying boat

Description: "The hydrodynamic characteristics of a model of the hull of the Short Calcutta (N.A.C.A. Model 47) are presented in non-dimensional form. This model represents one of a series of hulls of successful foreign and domestic flying boats the characteristics of which are being obtained under similar test conditions in the N.A.C.A. tank. The take-off distance and time for a flying boat having the hull of the Calcutta are compared at two values of the gross load with the corresponding distances and tim… more
Date: January 1937
Creator: Ward, Kenneth E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tanks test of a model of the hull of the Navy PB-1 flying boat - N.A.C.A. Model 52

Description: A model of the hull of the Navy PB-1 flying boat was tested in the N.A.C.A. tank as part of a program intended to provide information regarding the water performance of hulls of flying boats of earlier design for which hydrodynamic data have heretofore been unavailable. Tests were made according to the general method over the range of practical loadings with the model both fixed in trim and free to trim. A free-to-trim test according to the specific method was also made for the design load and … more
Date: August 1936
Creator: Allison, John M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tank tests of models of flying boat hulls having longitudinal steps

Description: Four models with longitudinal steps on the forebody were developed by modification of a model of a conventional hull and were tested in the National Advisory Committee for Aeronautics (NACA) tank. Models with longitudinal steps were found to have smaller resistance at high speed and greater resistance at low speed than the parent model that had the same afterbody but a conventional V-section forebody. The models with a single longitudinal step had better performance at hump speed and as low hig… more
Date: July 1936
Creator: Allison, John M. & Ward, Kenneth E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Similitude in Hydrodynamic Tests Involving Planing

Description: The problems of using models in planing tests are addressed. If one passes from the model to a hull of linear dimensions n times greater, the speeds are connected by the law of mechanical similitude. The normal forces given by the hydrodynamic equations (perfect fluid) also follow the law of dynamic similitude (Reech's method) and are multiplied by n(exp 3). A series of tests were performed and the actual results were compared to theoretical results.
Date: May 1936
Creator: Gruson, M. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Effect of the Angle of Afterbody Keel on the Water Performance of a Flying-Boat Hull Model

Description: NACA model 11-C was tested according to the general method with the angle of afterbody keel set at five different angles from 2-1/2 degrees to 9 degrees, but without changing other features of the hull. The results of the tests are expressed in curves of test data and of non-dimensional coefficients. At the depth of step used in the tests, 3.3 percent beam, the smaller angles of afterbody keel give greater load-resistance ratios at the hump speed and smaller at high speed than the larger angles… more
Date: September 1935
Creator: Allison, John M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic Tests of Models of Seaplane Floats

Description: "This report contains the results of tank tests carried out at free trim on seventeen hulls and floats of various types. The data as to the weight on water, trim, and relative resistance for each model are plotted nondimensionally and are referenced both to the total weight and to the weight on water. Despite the fact that the experiments were not made systematically, a study of the models and of the test data permits nevertheless some general deductions regarding the forms of floats and their … more
Date: May 1935
Creator: Eula, Antonio
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tank tests of a model of a flying-boat hull with a fluted bottom

Description: A 1/5-scale model of a flying-boat hull having flutes in the bottom both forward and aft of the step (NACA model 19) was tested to determine its water performance. The model was also tested after the successive removal of the flutes on the afterbody and forebody. The results from these tests are compared with those from tests of a model of the hull of the Navy PN-8 flying boat and it is concluded that the fluted-bottom model and its modifications are inferior to the model of the PN-8.
Date: March 1935
Creator: Dawson, John R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of Practical Hydrodynamics to Airship Design

Description: The purpose of the first two parts of this report is to present in concise format all the formulas required for computation of the hydrodynamic forces, so that they can be easily computed for either straight or curvilinear flight. Improved approximations are also introduced having a high degree of accuracy throughout the entire range of practical proportions. The remaining two parts of the report are devoted respectively to stability and skin friction, as functions of the same hydrodynamic forc… more
Date: 1933
Creator: Upson, Ralph H. & Klikoff, W. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some Ideas on Racing Seaplanes

Description: This report presents the author's designs and construction of various seaplanes to raced in the Schneider Cup. The results of tests are presented as well as discussions of various structures like floats and wings.
Date: November 1932
Creator: Pegna, Giovanni
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Transference of Heat From a Hot Plate to an Air Stream

Description: The object of the present study was to define experimentally the field of temperature and velocity in a heated flat plate when exposed to an air stream whose direction is parallel to it, then calculate therefrom the heat transference and the friction past the flat plate, and lastly, compare the test data with the mathematical theory. To ensure comparable results, we were to actually obtain or else approximate: a) two-dimensional flow; b) constant plate temperature in the direction of the stream… more
Date: April 1931
Creator: Elias, Franz
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Boundary Layer as a Means of Controlling the Flow of Liquids and Gases

Description: According to one of the main propositions of the boundary layer theory the scarcely noticeable boundary layer may, under certain conditions, have a decisive influence on the form of the external flow by causing it to separate from the wing surface. These phenomena are known to be caused by a kind of stagnation of the boundary layer at the point of separation. The present report deals with similar phenomena. It is important to note that usually the cause (external interference) directly affects … more
Date: March 1930
Creator: Schrenk, Oskar
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tank tests of twin seaplane floats

Description: The following report contains the most essential data for the hydrodynamic portion of the twin-float problem. The following points were successfully investigated: 1) difference between stationary and nonstationary flow; 2) effect of the shape of the step; 3) effect of distance between floats; 4) effect of nose-heavy and tail-heavy moments; 5) effect of the shape of floats; 6) maneuverability.
Date: October 1928
Creator: Herrmann, H.; Kempf, G. & Kloess, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of a twin-float seaplane during take-off

Description: This report presents the results of an investigation of the planing and get-away characteristics of three representative types of seaplanes, namely, single float, boat, and twin float. The experiments carried out on the single float and boat types have been reported on previously. This report covers the investigation conducted on the twin-float seaplane, the DT-2, and includes as an appendix, a brief summary of the results obtained on all three tests. At low-water speeds, 20 to 30 miles per hou… more
Date: January 1927
Creator: Crowley, John W., Jr. & Ronan, K. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Resistance to the Steady Motion of Small Spheres in Fluids

Description: "There seems to be little reliable information conveniently available as to the resistance encountered by small spheres moving steadily at moderate speeds in fluids. The present paper, while presenting nothing new in the way of either theory or data, has three objects: first to show that published data are sufficient to furnish approximate information; second to present this information in form convenient for computation; and, third to indicate where further research is needed" (p. 1).
Date: February 1926
Creator: Castleman, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Résumé of the Advances in Theoretical Aeronautics Made by Max M. Munk

Description: "In order to apply profitably the mathematical methods of hydrodynamics to aeronautical problems, it is necessary to make simplifications in the physical conditions of the latter. In a valuable paper presented by Dr. Max M. Munk, of the National Advisory Committee for Aeronautics, Washington, to the Delft Conference in April, 1924, these necessary simplifying assumptions are discussed in detail. It is the purpose of the present paper to present in as simple a manner as possible some of the inte… more
Date: 1926
Creator: Ames, Joseph S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of a single float seaplane during take-off

Description: At the request of the Bureau of Aeronautics, Navy Department, the National Advisory Committee for Aeronautics at Langley Field is investigating the get-away characteristics of an N-9H, a DT-2, and an F-5l, as representing, respectively, a single float, a double float, and a boat type of seaplane. This report covers the investigation conducted on the N-9H. The results show that a single float seaplane trims aft in taking off. Until a planing condition is reached the angle of attack is about 15 d… more
Date: January 1925
Creator: Crowley, J. W., Jr. & Ronan, K. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Simplifying Assumptions, Reducing the Strict Application of Classical Hydrodynamics to Practical Aeronautical Computations

Description: Note presenting a general method followed to simplify the numerical work in hydrodynamics, which consists of neglecting quantities of a lower order of magnitude. Four of the solutions covered in this report include the theory of the lateral air forces on airship hulls, theory of wing sections in a two-dimensional flow, theory of wings with a finite span, and propeller theory.
Date: November 1924
Creator: Munk, Max M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic tests for determining the take-off characteristics of seaplanes

Description: The resistance of water, even at low speeds, may be such as to render it impossible to take off. For this type of aircraft, it is therefore especially important to determine the take-off characteristics. A new and simple graphical method is given and appears to be the only one for the complete solution of the problem.
Date: May 1923
Creator: Verduzio, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Applications of Modern Hydrodynamics to Aeronautics

Description: The report gives, rather briefly, in part one an introduction to hydrodynamics which is designed to give those who have not yet been actively concerned with this science such a grasp of the theoretical underlying principles that they can follow the subsequent developments. In part two there follows a separate discussion of the different questions to be considered, in which the theory of aerofoils claims the greatest portion of the space. The last part is devoted to the application of the aerofo… more
Date: 1923
Creator: Prandtl, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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