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Comparative Tests of Run-of-Mine and Briquetted Coal on the Torpedo Boat Biddle

Description: From Introduction: "With the particular equipment used in the tests both coal and briquets were far from smokeless; consequently the data of this bulletin are applicable only by analogy to parallel operation with a coal more nearly smokeless, but nevertheless applicable with much reliability. It was the original intention to make a set of preliminary steaming tests alongside a dock (which tests furnish material for this bulletin) an to finish with a set of running tests at sea; but the running tests were never made. for lack of time and men."
Date: 1911
Creator: Ray, Walter T. & Kreisinger, Henry
Partner: UNT Libraries Government Documents Department

A Method for Making Quantitative Studies of the Main Spray Characteristics of Flying-Boat Hull Models

Description: Report presenting a method and apparatus for making quantitative tests of the spray characteristics of flying-boat-hull models. The method is applied to three related models of flying-boat hulls which differed in one major characteristic of shape: the overall dead rise.
Date: November 1943
Creator: Locke, F. W. S., Jr.
Partner: UNT Libraries Government Documents Department

Effect of Forebody Warp and Increase in Afterbody Length on the Hydrodynamic Qualities of a Flying-Boat Hull of High Length-Beam Ratio

Description: Note presenting an investigation with the aim of achieving improved hydrodynamic qualities for flying boats, which involved determining the combined effect of a warped forebody and extended afterbody on the hydrodynamic characteristics of a full having a basic length-beam ratio of 15. Results regarding longitudinal stability, landing stability, spray characteristics, and landings in waves are provided.
Date: November 1949
Creator: Kapryan, Walter J.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of a Refined Deep-Step Planing-Tail Flying-Boat Hull with Various Forebody and Afterbody Shapes

Description: From Summary: "An investigation was made in the Langley 300 mph 7-by 10-foot tunnel to determine the aerodynamic characteristics of a refined deep-step planing-tail hull with various forebody and afterbody shapes. For comparison, tests were made on a streamline body simulating the fuselage of a modern transport airplane. The results of the tests, which include the interference effects of a 21-percent-thick support wing, indicated that for corresponding configurations the hull models incorporating a forebody with a length-beam ratio of 7 had lower minimum drag coefficients than the hull models incorporating a forebody with a length-beam ratio of 5. Longitudinal and lateral stability was generally about the same for all hull models tested and about the same as that of a conventional hull."
Date: 1953
Creator: Riebe, John M. & Naeseth, Rodger L.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of a Refined Deep-Step Planing-Tail Flying-Boat Hull with Various Forebody and Afterbody Shapes

Description: From Introduction: "The results of one phase of this investigation, presented in reference 1, have indicated that hull drag can be reduced without causing large changes in aerodynamic stability and hydrodynamic performance by the use of high length-beam ratios. Another phase of the investigation, reference 2, indicated that hulls of the deep-step planning-tail type have much lower air drag than the conventional type of hull and about the same aerodynamic stability; tank tests, reference 3, have indicated that this type of hull also has hydrodynamic performance equal to and in some respects superior to the conventional type of hull. Unpublished tank tests have indicated that the hull models presented in the present paper (with the possible exception of the forebody alone for which data are not available) will have acceptable hydrodynamic performance."
Date: June 1952
Creator: Riebe, John M. & Naeseth, Rodger L.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Three Deep-Step Planing-Tail Flying-Boat Hulls and a Transverse-Step Hull with Extended Afterbody

Description: From Summary: "An investigation was made to determine the aerodynamic characteristics in the presence of a wing of three-step planning-tail flying-boat hulls which differed only in the amount of step fairing. The purpose of comparison, tests were also made of a transverse-step hull with an extended afterbody."
Date: August 1952
Creator: Riebe, John M. & Naeseth, Rodger L.
Partner: UNT Libraries Government Documents Department

Porpoising: A Comparison of Theory With Experiment

Description: Report presenting a direct comparison between the observed and the calculated longitudinal dynamic stability of a particular dynamic model of a flying boat moving on the water. Good agreement was obtained between experiment and theory for trim angles in the vicinity of lower limit, at one speed a little above the hump.
Date: July 1943
Creator: Davidson, Kenneth S. M.; Locke, F. W. S., Jr. & Suarez, Anthony
Partner: UNT Libraries Government Documents Department

Hydrodynamic Investigation of a Series of Hull Models Suitable for Small Flying Boats and Amphibians

Description: Note presenting the results of an investigation to obtain hydrodynamic information on a series of hull models suitable for small flying boats or amphibians of from 2000 to 5000 pounds gross weight. The series of hulls consisted of a basic hull with simple lines, and of plus and minus variations to the design in which the beam, stern-post angle, and afterbody length were altered. The results show that it is possible to design a hull with simple lines that will be suitable for small flying boats or amphibians.
Date: November 1951
Creator: Hugli, W. C., Jr. & Axt, W. C.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a flying-boat hull having a length-beam ratio of 15 and a warped forebody

Description: From Introduction: "The results of two phases of this investigation, presented in references 1 and 2, have indicated possible ways of reducing hull drag without causing large changes in aerodynamic stability and hydrodynamic performance."
Date: February 11, 1949
Creator: MacLeod, Richard G.
Partner: UNT Libraries Government Documents Department

An analysis of the airspeeds and normal accelerations of Sikorsky S-42A airplanes in commercial transport operation

Description: From Introduction: "This paper gives the results of an analysis of V-G data taken on four Sikorsky S-42A flying boats operated on Caribbean routes and along the east coast of South America during the period from 1936 to 1939. The available S-42A data are summarized and flight-load results are compared with the results of analyses made in the past."
Date: October 1948
Creator: Walker, Walter G.
Partner: UNT Libraries Government Documents Department

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 included.
Date: April 1938
Creator: Diehl, Walter S.
Partner: UNT Libraries Government Documents Department

A new method of studying the flow of the water along the bottom of a model of a flying-boat hull

Description: A new method of studying the flow of the water along the bottom of a model of a flying-boat hull is described. In this method, the model is fitted with a transparent bottom and is divided down the center line by a bulkhead. The flow is observed and photographed through one-half of the model by means of the diffused illumination from a battery of lamps contained in the other half of the model. Photographs of the flow, particularly of the changes that occur when the step ventilates, are shown. The results of the present investigation indicate that the method has considerable promise, chiefly in connection with motion-picture studies.
Date: February 1940
Creator: Ward, Kenneth E.
Partner: UNT Libraries Government Documents Department

The design of the optimum hull for a large long-range flying boat

Description: Report presenting some principles for designing the optimum hull for a large long-range flying boat in order to suit the requirements of minimum drag, seaworthiness, and ability to take off and land at all operational gross weights. The principles include the use of moderate gross-load coefficients, ample forebody lengths, and deep steps and the close adherence of the form to that of a streamline body of revolution with a moderate fineness ratio.
Date: September 1944
Creator: Parkinson, John B.
Partner: UNT Libraries Government Documents Department

A collection of the collapsed results of general tank tests of miscellaneous flying-boat-hull models

Description: Presented here are the summary charts of the collapsed results of general tank tests of about 100 flying boat hull models. These summary charts are intended to be used as an engineering tool to enable a flying boat designer to grasp more quickly the significance of various hull form parameters as they influence his particular airplane. The form in which the charts are prepared is discussed in some detail in order to make them clearer to the designer. This is a data report, and no attempt has been made to produce conclusions or correlations of the usual sort. However, some generalizations are put forward on the various methods in which summary charts may be used.
Date: March 1947
Creator: Locke, F. W. S., Jr.
Partner: UNT Libraries Government Documents Department

General porpoising tests on flying-boat-hull models

Description: Report presenting evidence in support of the propriety of substituting a general porpoising test of flying boat hull models in place of the usual specific test. The results of a general test are presented and compared with the results of a specific test of the same model.
Date: September 1943
Creator: Locke, F. W. S., Jr.
Partner: UNT Libraries Government Documents Department

General resistance tests on flying-boat hull models

Description: Report re-examining known procedures for handling general resistance testing on flying-boat hull models, with particular attention paid to saving test time and improving the usefulness of the results to designers. While specific testing will likely always be needed, the procedures given in the report for condensing resistance data should make data analysis easier to apply to design.
Date: February 1944
Creator: Locke, F. W. S., Jr.
Partner: UNT Libraries Government Documents Department

An analysis of the skipping characteristics of some full-size flying boats

Description: From Introduction: "The purpose of this report is to gather together in one place information on the skipping characteristics of number of flying boats. A graph showing the influence of the hull form on the skipping characteristics is given which should be useful in laying out the proportions of the hull in preliminary design to insure good landing behavior."
Date: January 1946
Creator: Locke, F. W. S., Jr.
Partner: UNT Libraries Government Documents Department

A correlation of loadings and afterbody length-beam ratios of various flying-boat hulls

Description: "The gross weight, beam, and afterbody length of 12 contemporary flying boats and amphibians with pointed afterbodies are tabulated and correlated. For most of the hulls considered, the afterbody length-beam ratios are shown to be directly proportion to the gross-load coefficients" (p. 1).
Date: June 1946
Creator: Parkinson, John B.
Partner: UNT Libraries Government Documents Department

Rough-water Landings of a 0.1-Size Powered Dynamic Model of the XP5Y-1 Flying Boat with Two Types of Afterbody - Langley Tank Model 228 (TED No. NACA DE309)

Description: A 0.1-size powered dynamic model of a large, high-speed flying boat was landed in Langley tank no. 1 into oncoming waves 4 feet high (full size). The model was tested with two afterbodies of differing lengths (4.12 and 6.63 beams). The short afterbody had a constant angle of dead rise of 22.5deg and a keel angle of 6.5deg. The long afterbody had warped dead rise and a keel angle of 8.5deg. The vertical accelerations were slightly greater and the maximum angular accelerations and maxim= trims were slightly less for the model with the long afterbody than for the model with -the short afterbody. A wave length of 210 feet (full size) imposed the highest accelerations on the model with either the long or the short afterbody.
Date: February 9, 1949
Creator: Garrison, Charlie C.
Partner: UNT Libraries Government Documents Department

Landing characteristics in waves of three dynamic models of flying boats

Description: Powered models of three different flying boats were landed in oncoming waves of various heights and lengths. The effects of varying the trim at landing, the deceleration after landing, and the size of the waves were determined. Data are presented on the motions and accelerations obtained during landings in rough water.
Date: January 1952
Creator: Benson, James M.; Havens, Robert F. & Woodward, David R.
Partner: UNT Libraries Government Documents Department

On the Theory of Unsteady Planing and the Motion of a Wing With Vortex Separation

Description: The disturbance imparted to water by a planing body give rise to a wave form of motion on the free surface, the length of the waves increasing indefinitely with increase in the Froude number and being directly proportional to the latter in the case of the plane or two-dimensional problem. At large Froude numbers the effect of the weight shows up to any appreciable extent only at some distance from the body, so that the flow near the body can be considered as part of a flow of an infinitely extending weightless fluid. This paper is a consideration of these characteristics as well as a formulation of the planing problem and its relation to the problem of a thin wing.
Date: May 1940
Creator: Sedov, L.
Partner: UNT Libraries Government Documents Department