bluuebunny/crossref_metadata_2025 huggingface dataset:
Conversion of Seamaster Cargoliners to Full Containerships
Authors: Munroe Hugh F.
Published: January 2021

It is the intent of this paper to provide certain specific design information on the operator's decisions leading to accomplishment of a major 5-ship conversion program and follow that background summary with comments on the postconversion service performance. The paper is intended to supplement and/or complement a paper simultaneously prepared by the conversion contractor covering the actual detailed planning and accomplishment of the conversion.
Assessment of the Japanese Shipbuilding Industry
Authors: Masubuchi Koichi , Terai Kiyoshi
Published: January 2021

This paper first discusses the status of the Japanese shipbuilding industry—how the industry has grown, where shipyards are located, what types of ships are fabricated, etc. It then describes historical changes of the Japanese shipbuilding industry, in the 1950's and before, in the 1960's, and in the 1970's and the future. The paper discusses advancement of ship construction technology-developments through the 1950's, in the 1960's, and in the 1970's and the future—as well as factors that contributed to the growth of the Japanese shipbuilding industry.
Bayesian Analysis of Oil Spill Statistics
Authors: Devanney J. W. , Stewart Robert J.
Published: January 2021

This paper takes a two-step approach to the problem of estimating the likelihood of oil spill frequency and magnitude associated with a given amount of oil transport and production activity. The paper uses Bayesian reasoning plus actual spill data gathered from a variety of sources to generate (a) the density of the number of spills which will occur in the life of a project and (b) the density of the amount of oil which will be spilled in an individual incident. These two densities are then combined to obtain the density of the total volume of oil which will be spilled over a project's life.
DD 963 Power Plant
Authors: Rains Dean A.
Published: January 2021

Gas turbines were selected as the main and auxiliary power plants for the new DD 963 Class ships, which is a departure from previous designs for U. S. Naval power plants. This paper describes the DD 963 power plant design, including the propulsion and supporting auxiliary machinery.
Theory of Sailing Applied to Ocean Racing Yachts
Authors: Myers Hugo A.
Published: January 2021

A systems analysis approach is used to study the performances of ocean racing yachts, and to support a rating system which considers wind conditions and course angles. Basic aerodynamic and fluid-dynamic theory is applied to derive an engineering mathematical simulation of a boat's performance. The result is a set of five equations in five unknowns. Given the true wind velocity and course sailed, the equations are solved for boat speed, apparent wind speed, apparent wind angle, leeway angle, and heeling angle. The theory is compared with full-scale towing tests and sailing measurements for several yachts, ranging from a 23-ft cruiser to a 68-ft (12-meter) racer. The theoretical results fall within the measurement accuracies for all course angles and wind conditions. Yacht performance curves are then compared for the detailed effects of windward capabilities and rig variations for various true wind speeds. A "rating matrix" approach is discussed, which could be used to rate fairly a wider range of yacht sizes, types, wind conditions, and course angles than present rating systems can accommodate.
Prospects for Very-High-Speed Hydrofoils
Authors: Conolly A. C.
Published: January 2021

Severe hydrodynamic problems remain to be solved before hydrofoils can be designed to operate on the open ocean at speeds between 50 and 80 knots. These problems stem from two sources, cavitation and the free-water surface, complicated by the action of waves. Recently, a natural air venting phenomenon has been investigated which shows promise of being a very satisfactory mode for the operation of highspeed hydrofoils up to speeds at least as high as 80 knots. "Hyperventilation" is the complete breaking open to the atmosphere of a vapor or partially air-filled cavity, giving rise to an underwater planing condition. What was previously thought of as a transient, extremely shallow submergence phenomenon has been shown to be a stable and predictable operating condition with a wide "window" encompassing speed, depth, angle of attack, foil section, and planform geometry. Model experiments also showed that the discovery explains a problem that has been encountered with present-generation subcavitating hydrofoil boats; that is, if a non-surface-piercing foil broaches the water surface and then reenters, it fails to pick up lift immediately and the hull consequently impacts the water heavily.
Cost Considerations for Electrical/Electronic System Installation Design
Authors: Carstensen Russell V.
Published: January 2021

With the advent of limited budgets and increased system complexity, more intensive consideration of cost factors for various technical options must be undertaken at the design level. This paper presents certain general aspects of shipboard installation costs for electrical and electronic systems that may be used by the designer to plan a technically adequate installation for the least possible cost. The estimating process is discussed first, and how the designer may evaluate cost against function. This is followed by a discussion of standard material item cost (both procurement and local manufacture), lead time, and general availability. The paper closes with a set of recommendations to aid the designer in reducing system installation costs. Discussers Parker W. Snapp Edward C. Stewart
Large Floating Dry Docks for Large Ships
Authors: Crandall Paul Stuart
Published: January 2021

Advances in floating dry docks and transfer systems enable the floating docks to meet new needs of launching and repairing the very large vessels so important in today's shipping, as demonstrated at several U. S. yards. At most sites, floating dry docks are competitive economically with both basin dry docks and shallow basin building docks. They can be designed to handle as large ships as necessary, are relatively expandable, can be sold and moved, use free water space instead of valuable real estate, and can assume controlled drag and list. They can be built in two sections to give the versatility of independent use and so improve the duty factor. With modern transfer systems, floating docks offer a convenient way to build in the yard and safely launch into (or retrieve from) the water. Steel docks with present-day hull protection should serve efficiently for 50 years or more, an acceptable period in view of ever-changing industry needs.
The Evolution of Shipboard Accommodations and Habitability Standards Aboard U. S. Merchant Ships
Authors: Cherrix Charles B. , Coffman Eugene L.
Published: January 2021

This paper discusses some current practices, future trends, and suggested improvements in U. S. merchant ship habitability. It develops some historical background, from the World War II Liberty, Victory, and T2 Tanker programs up through the present. Some future trends, such as two-room suites for officers and crew, as well as some thoughts on probable future crew work assignments are discussed.
RO/RO Ships—State of the Art in Australasia
Authors: Taylor G. R.
Published: January 2021

Since the introduction of the first Australian roll-on/roll-off (RO/RO) vessel into service in 1959, there has been a continuing trend toward the adoption of this type of vessel. Such a trend has no doubt been stimulated by the dramatic increases in the cost of constructing and operating ships in a climate of continuing inflation. A brief history of numerous RO/RO ships is given, and various design features described, since in many cases they formed the background to the development of vessels only now entering service. Various design features of the RO/RO vessel are discussed with particular reference to the four gas turbine electric powered vessels in service and under construction for Union Steam Ship Company of New Zealand (USSCo). Details are also given, where applicable, of the two gas turbine powered steel carriers built for and by Broken Hill Proprietary Company Ltd. (BHP Co). An RO/RO bulk carrier which recently entered service is described, and, as an illustration of the continuing development in the field of RO/RO ships, several new projects are described in some detail.
The National Shipbuilding Research Program, 1971-1976
Authors: Garvey John J.
Published: January 2021

This paper is a description of the organization and operation of a unique research program sponsored by the Federal Government in full partnership with the U. S. shipbuilding industry. The objective of the program is to improve the productivity of this industry and to reduce Government subsidy. Since the program began in 1971, almost 90 projects have been funded by the Government at a cost of $15 million. In addition, the industry has contributed in manpower, material, and facilities in excess of $5 million. The bulk of the projects involve development and demonstration of production technology for shipbuilding. These include welding, material handling, ship outfitting, production methods, manufacturing automation, and production-oriented design. In addition to describing the technical and organizational content of the program, the paper is intended to be a case study of a successful government/industry approach to improve the total innovation process within a mature industry.
The National Planning Conference on the Commercial Development of the Oceans
Authors: Sonenshein Nathan
Published: January 2021

Four Federal agencies—the Maritime Administration, the National Oceanic and Atmospheric Administration, the Department of Interior, and the Energy Research and Development Administration—in cooperation with private industry sponsored the title Conference. This paper summarizes the results of the Conference, outlining the recommendations of the five working panels and emphasizing those aspects of special interest to SNAME members.
Shipboard Data Multiplex System—A Method of Reducing Shipboard Electrical Cable Requirements
Authors: Carstensen Russell V.
Published: January 2021

A modern naval destroyer requires almost 183 000 m (60000 ft) of copper cable for information transfer between units of a given system or as interface connections between systems. Over a 30-year life cycle, the ship may undergo regular overhaul four times and an extensive modernization at least once. During each of these evolutions a large portion of the through-ship cabling installed for information transfer, data exchange or equipment control must be rerouted or replaced, at substantial cost. By multiplexing data exchange on a few coaxial cables, the Shipboard Data Multiplex System (SDMS) will replace or substantially reduce most through-ship signal cable requirements, and thus cost far less than a conventional fixed-wire installation. When reconfiguration is required at a later date, only changing short interface cables and inserting small Programable Read Only Memories (PROM's) into the multiplexers will be necessary. This paper outlines through-ship electrical cable requirements, wireway design and installation costs, and a comparison between SDMS and a conventional fixed-wire system for a major combatant.
Management of Mid-Atlantic Offshore Development Risks
Authors: Snider W. D. , Buffleben G. J. , Harrald J. R. , Bishop K. F. , Card J. C.
Published: January 2021

Careful attention must be given to identification, evaluation, and control of risks associated with development of mid-Atlantic offshore oil and gas if environmental damage and development delays are to be avoided. A number of approaches to safety, or risk management, are possible, but all seek to answer the central management, are possible, but all seek to answer the central management question, "Am I safe enough?" System safety methods are now available which can assist us in making intelligent decisions on safety measures to be incorporated in offshore development plans. Development of offshore oil and gas resources has brought new risks to exploratory and development drilling, production, and transportation operations. Concern over these risks has prompted a number of studies. After a brief review of these studies, the authors describe investigations in two areas: oil discharges in the Gulf of Mexico and worldwide accidents involving mobile offshore drilling units. A number of measures to reduce risks are being considered or have already been taken by government and industry. Greater application of system safety procedures offers new potential for reducing the risks in offshore development.
Advanced Naval Vehicles: Who Needs Them?
Authors: O'Neil William D.
Published: January 2021

A broad, informal review is provided of the problems involved in justifying heavy expenditures for development of new types of Naval vehicles. It is argued that questions of need and worth are commonly treated too shallowly. A number of frequently urged simple justifications are examined and dismissed. The author closes by urging that vehicle proponents attempt to justify their proposals in terms of specific impact on the results of realistic Naval scenarios.
Update: Domestic LNG Vessel Construction
Authors: Connors Thomas G.
Published: January 2021

The paper gives a picture of the progress of the present domestic LNG vessel construction program over the past four years, dealing exclusively with three U. S. shipyards constructing LNG vessels under the Construction Differential Subsidy (CDS) program. The paper dwells largely on the specialized facilities, equipment and techniques required and the problems encountered in the construction of LNG cargo containment systems for three designs and shows the successful solutions to those problems.
Simulation of the Maneuverability of Inland Waterway Tows
Authors: Petrie George L.
Published: January 2021

A mathematical model has been developed to simulate the motion of a barge and towboat flotilla maneuvering through an inland waterway channel. The formulation of the mathematical model, including the hydrodynamic force representations and the rudder and propeller control algorithms, and its implementation in a digital computer program are described. Potential applications for utilization of the model are discussed, and some typical results are given.
Estimated Return-on-Investment of Oil Tankships
Authors: Walsh Robert G.
Published: January 2021

A model to estimate return-on-investment of oil tankships is developed to assess the historical returns of various types of tanker ownership. Looking back in time may offer some guidance for the future and also expose pitfalls of this investment area. Study results are that the return-on-investment for oil tankships has historically ranged from at best break-even to about 30 percent for the early 50's and 20 percent for the late '60's and early '70's. Debt financing can be used to increase the rate of return on equity. In the mid-'60's because of increasing tanker size and overall tonnage capacity, charter market rates were at a long-term low. During this period the loss from operation was below the annual cost of debt. Therefore, to minimize the loss, remaining in operation was a better alternative than laying up the vessel. Because of these extreme results, market strategy must be one of correct timing of tanker purchases in order to pay off debt financing or achieve sufficient capital recovery to be ready for protracted lower market rates. In developing the rate-of-return model the calculations require estimating tanker purchase price, operating cost, charter-market income, and resale or scrap value. In addition, assumptions are made on the types of financing available. These are the debt-free case, a standard percentage financed, and a leveraged lease where 100 percent of the purchase price is financed.
Design Considerations for Propellers in a Cavitating Environment
Authors: Blount Donald L. , Fox David L.
Published: January 2021

Cavitation adds a dimension to propeller operation that necessitates rational design practice to approach a good balance of craft requirements. This paper discusses propeller characteristic format to reduce the computation time to make performance predictions and propeller selection for partially and fully cavitating conditions. In addition, maximum propeller thrust and torque loading limits are defined for four different blade section shapes, including recommended design limits. Discussers Jim W. Bordeaux Mark Oaks
MV Silverado
Authors: Wilson Thomas B.
Published: January 2021

The design, construction and testing of a 120-ft fiber glass reinforced plastic (FRP) motor vessel are described. Designed by and built under the supervision of the author, Silverado is the largest FRP commercial vessel in the world. Built to class and under survey for unrestricted ocean service, it represents an incremental step forward in fiberglass technology accomplished by the private sector of the economy. Powered by two marine diesel engines, Silverado is a high-performance vessel built to luxury yacht standards of finish and accommodations. She is equipped with a viewing port amidships on the port side for underwater viewing and trim tabs for speed optimization. A description is given of the design chronology, the materials utilized and those available, the design process and the author's philosophy of design, the production process, installed equipments, classification society requirements, material tests and results, and an example of the economics of FRP construction.
Avoidance and Mitigation of Shipbuilding Contract Claims
Authors: Lamartin F. H.
Published: January 2021

The author draws upon experience with the major shipbuilding claims of this decade to identify what the Navy could do to avoid or mitigate future claims. Claims are not totally avoidable. They become a serious problem when they are unanticipated or difficult to resolve. Their dominant cost elements cover delay and disruption and often involve the entire shipyard environment. Early identification and mitigation of such delay and disruption are needed. Recent Navy claim avoidance steps include changes of contract form to reduce risks, emphasis on controlling changes, and attempts to attribute disruption costs to individual changes. Eight additional actions which the Navy could take are identified. The most significant are: improved preaward cost and schedule evaluation procedures; improved control procedures and techniques for timely identification of potential cost growths and delays; periodic waiver of claims; and prenegotiation of remedies.
IMCO Conference on Tanker Safety and Pollution Prevention
Authors: Snider W. D.
Published: January 2021

Public concern over risks associated with marine transportation of oil following a series of oil tanker accidents in and near U. S. waters during the winter of 1976–1977 resulted in the announcement by President Carter on 17 March 1977 of a series of measures intended to reduce such risks. Among the measures recommended was a call for a special international conference to consider U. S. proposals for improvements to the international system of tanker inspection and certification and strengthening of ship construction and equipment standards. As a result, the International Conference on Tanker Safety and Pollution Prevention, completed some 11 months to the day after the President's request, adopted important new measures to improve the safety of oil tankers and help prevent pollution of the seas from ships. The measures adopted achieved and in some cases exceeded nearly all of the U. S. goals for improvements to inspection and certification and ship construction and equipment requirements. The adoption of these measures, along with other international and domestic actions now in progress, will do much to reduce the risks associated with the marine transportation of the oil that is so essential a part of our lives today.
Propellers for High-Performance Craft
Authors: Allison John L.
Published: January 2021

This paper presents a brief historical review of marine propeller development leading to modern design, selection, and matching methods for high-performance craft such as planing hulls, hydrofoils and surface effect ships. Subcavitating propeller theory is summarized, and some limitations are discussed with regard to high-speed applications. An outline of supercavitating propeller theory is provided together with brief details of design procedures and the limitations of available data. The special problems of application of supercavitating propellers to surface effect ships are discussed briefly. Topics include sidehull installations, matching for hump and cruise, need for partial submergence and controllable pitch, strength considerations, and model versus full-scale performance. A review of recent progress in the application of supercavitating propellers to surface effect ships is presented, including comparisons of predicted full-scale blade pressures and stresses with actual full-scale measurements of speeds up to 80 knots. Future trends and goals are discussed, including development of improved performance prediction methods, rational structural design procedures, and new types of installation configuration. Much of the new information contained in this paper arises out of work performed under contract for the U. S. Navy Surface Effect Ship Program Office (PMS304) by Bell Aerospace Textron.
Marine Technology
Authors: Sartor Thomas J. , Gibbon Robed P.
Published: January 2021

This paper describes the four original Farrell Lines C6-class containerships and the lengthening of two of the ships by 144 ft (44 m) to C8 class. Also described are two additional C8-class ships presently building which will be the largest to be built in the Unites States. These ships—particularly those of the C8 class-contain many novel features, including an overfeed refrigeration system for the reefer cargo holds, new types of insulation for the refrigerated spaces, and an on-deck securing system that eliminates the need for container lashing. The high-efficiency automated power plant is described along with its operating experience. The Farrell Lines' ships can be considered as representing two "areas" of three design variations; namely, the "deckhouse" area (including machinery space, accommodations, etc.)—generally unaffected by vessel type—and the cargo-carrying area (both on-and underdeck)—almost exclusively influenced by cargo characteristics. The three design variations of this one owner—C6-S-85a, C8-S-85c, and C8-S-85d—represent, respectively, a basic design acceptable with variations for two different owners: a lengthening/conversion of two of the four vessels of the first design to extensively increase their refrigerated cargo capacity (within the limitations of conversion) and two near-sister ships of the lengthened/conversion design (maintaining most of the design characteristics but free of conversion limitations). Finally, the design coordination between the two owners is discussed along with some "dream" features for the new design.
Shipboard Installation of Fiber Optic Cable
Authors: Carstensen Russell V.
Published: January 2021

Fiber optic transmission systems using small-diameter glass rods to transmit light signals over long distances present an effective alternative to conventional copper cable for signal exchange on board ship. Connectors containing light sources (transmitters) and detectors (receivers), along with an impressive variety of fiber optic cable types, are now available from commercial sources at prices that compete favorably with conventional wire and cable. Marine qualification is expected in the near future. This paper presents a discussion of the advantages of fiber optic cable systems as a method of accomplishing signal exchange on board ships and outlines some of the problems that may be encountered when actually installing fiber optic cable on ships.
Cogas: Marine Power Plant for Energy Savings
Authors: Giblon Robert P. , Rolih I. Hilary
Published: January 2021

This paper discusses one propulsion plant that may be adopted by shipowners today using known and proven technology whereby energy savings of 30 to 35 percent over the present steam or gas turbine power plants may be attained, as well as significant but somewhat lesser savings over diesel and present-day steam reheat power plants. The propulsion plant examined is based on the combined gas-steam cycle that is widely used for shoreside electric power plants and is sometimes referred to as the STAG or COGAS cycle. The COGAS plant consists of an aircraft-derivative gas turbine driving a reduction gear in tandem with a steam turbine which receives its steam from a heat-recovery boiler in the gas turbine exhaust gas ducting. Included in the paper is information on various alternative COGAS cycles and methods of control; also included are economic comparisons of the operating costs of COGAS and steam propulsion plant installed on a large containership and a tanker. The paper is based on a study prepared for the U. S. Department of Commerce (MarAd) that included inputs from Curtiss-Wright Corp., General Electric Co., Foster Wheeler Boiler Corp., Sun Shipbuilding & Dry Dock Co., and George G. Sharp, Inc.
Calculating Curves of Form Using the Hand-Held Programmable Calculator
Authors: Cromer Paul B.
Published: January 2021

This paper describes a program which the author has written for a programmable calculator for computing curves of form. The properties of the trapezoid and the mathematical expressions for them, along with expressions for summing the longitudinal and transverse moments of inertia of the elements of area making up a waterplane, form the basis of the program. The author discusses these relationships, shows how they are put in forms most usable by the calculator, and explains their function in the program. The choice of the number and spacing of stations used on a given waterplane to produce offsets or half-breadths for entry into the program is described, along with the three main uses for the program: doing curves of form for a hull in its early stages of design, making a final set of curves for a completed hull design, and computing a set of curves for an existing hull from its lines, construction drawings, or direct measurements. Finally, the advantages to the user of the program are described: a set of curves of form can be computed when and where it is needed, the accuracy is determined by how many trapezoids are used to approximate the waterplanes, and all calculations are performed automatically.
Operational Considerations for Designing Machinery-Aft Condenser-Condenser Scoop Systems
Authors: Latorre Robert
Published: January 2021

Condenser scoops have attractive features for circulating cooling seawater through the main condenser. Further developments are required, however, to enable the designer to fully utilize the simplification and cost reduction attributed to the scoop system. Therefore this paper reviews recent machinery-aft condenser installations, developments in inlet and outlet scoop designs, and boundary-layer measurements at the outlet scoop locations of a 91 000-dwt and a 160 000-dwt tanker. A rational approach based on Hotta's formulation is discussed for estimating the effects of seawater temperature, condenser tube fouling, and reduced scoop flow during operation on the condenser vacuum. A simulation study using the Hampton Maru service data is presented to illustrate this approach. Relevant experience in condenser corrosion and fouling is also reviewed and a proposal for using Campbell's condenser tube tester in shipboard condenser corrosion and fouling research is presented.
Tension-Leg Platform Design: Interaction of Naval Architectural and Structural Design Considerations
Authors: Capanoglu Cuneyt
Published: January 2021

As oil exploration and production move into water depths over 1000 ft (305 m), several companies are investigating compliant structures as possible solutions to the economic and engineering problems involved. This paper focuses on the tension-leg type of platform, a positively buoyant structure kept on location by a pretensioned anchoring system. The basic approach to design of a tension-leg platform system, the various components of the system and the interaction between naval architectural and structural design considerations are presented. The author points out that planning for a successful design must include:preparation of good design criteria,determination of variables,evaluation of variables for sensitivity and interaction,accurate and timely engineering decisions in selection of a set of parameters, andparallel studies covering fabrication, transportation and installation requirements.

Appendices give the mathematical bases for computing motions of the tenslon-leg platform and graphic illustrations of platform characteristics and the effects of typical exciting forces.
Containership Economics for Effective Decision-Making Analysis
Authors: Caracostas Nicholas
Published: January 2021

The principles of "production economic" theory are applied to containership economics. The paper indicates how the complex nonlinear problem of selecting the ship container capacity and speed satisfying a given level of demand for container transportation can be solved, utilizing graphical procedures based on production theory. The theory presented in the paper deviates from past procedures of ship optimization in that the optimization problem is examined in the light of transport elasticities, sailing intervals and imperfect competition among containership firms. A containership fleet optimization example utilizing production theory has been included.
Computer-Aided Propeller Preliminary Design Using the B-Series
Authors: Triantafyllou Michael S.
Published: January 2021

Preliminary propeller design is formulated by considering the interactions of the engine, the hull, the wake and the propeller, while the fuel consumption is established as the optimization criterion. The purpose of this study is to formulate the problem in a clear manner, illustrated by examples, in order to develop an efficient design tool which will be used to deal with the complex problem of evaluating the performance of a ship on a specific sea route, given the weather statistics. The optimization procedure is developed in a mathematical form for fuel consumption minimization and then applied in conjunction with the B-Series, whose value is generally recognized. A critical analysis of the B-Series data showed the need for a laminar flow correction. A method has been implemented and the corrected data have shown excellent agreement with experimental data. Finally, a simplified example is worked out to demonstrate the optimization of the performance of a vessel on a specific sea route.
Mooring of Surface Vessels to Piers
Authors: Chernjawski Michael
Published: January 2021

This paper presents a new analytical method of determining the tension forces in mooring lines of surface vessels. The method will aid the ship designer in developing fixed mooring systems with more accuracy than in the past. The analytical model developed considers the hull to be rigid and restrained broadside to a shallow-water pier with resilient fenders in use. The approach to the problem involves (a) determination of wind, current, and equivalent static wave forces at specified headings; (b) calculation of buoyant restoring forces caused by trim, heel, and immersion of the hull; (c) derivation of a combined mooring line stiffness matrix in terms of direction angles, lengths, cross-sectional properties, and nonlinear modulus of elasticity; and (d) derivation of generalized stiffness matrix for fixed mooring system and determination of tension forces in mooring lines using matrix algebra procedure and incremental load method. Special emphasis is placed on the cumulative elastic behavior of the mooring lines and on the manner in which the elasticity of the lines controls the vessel movement.
Has Stability Delayed the Delivery of Your Tug?
Authors: McGowan John F. , Meyer Richard B.
Published: January 2021

The authors present a simplified method of stability analysis applicable to tugboats which must be reviewed by the U. S. Coast Guard for load line assignment. The paper includes a brief review of tugboat stability leading up to the present criteria applied by the Coast Guard. The present criteria are included. The proposed method consists of two or three conditions which, upon satisfactory analysis, provide considerable leeway to the tugboat captain in the manner in which he operates his vessel. The method of analysis and necessary definitions and interpretations are presented. The authors have made note of especially troublesome areas of design and some good design practices which will improve the stability of tugboats.
The Third-Generation Deep-Sea RO/RO
Authors: Ando Hiroyuki , Miura Akio , Namba Sohachi
Published: January 2021

The deep-sea roll-on/roll-off vessel Boogabilla was successfully completed in the middle of August 1978. For a ship of the roll-on/roll-off type, the Boogabilla has several revolutionary features, such as a large-bore, slow-speed diesel engine, three parallel trafficways, and a jumbo angled stern ramp. These features are described in the paper, along with the general arrangement, including machinery spaces, optimization of hull form and propeller, structural design, safety measures, noise control, and other particulars that required special consideration.
Integrated Tug/Barge Valerie F: Design and Bulk Cargo Handling Operations
Authors: Seymour David J. , Kossa Miklos
Published: January 2021

The integrated tug/barge (ITB) Valerie F transports mixed bulk cargo between the East and West Coasts of the United States. The concept of barge wing tanks dedicated to rice with center cargo holds for general bulk cargo provides the backhaul capability necessary for profitable round-trip voyages. This paper compares the design and performance of the tug/barge with that of the Rice Queen, a converted tanker the Valerie F was built to replace. Typical cargoes for the ITB are described, as well as her self-unloading equipment, tug-to-barge connector, propulsion machinery, and the bulk cargo handling equipment and facilities at her ports of call, particularly those at her home ports of Sacramento and Stockton, California.
Motion Studies of a Vessel with Water on Deck
Authors: Dillingham Jeff
Published: January 2021

The seakeeping characteristics of a small fishing vessel are investigated. The type of vessel under consideration has a large flat deck which may, under severe considerations, remain partially or totally awash. We consider the effect of such deck water on the vessel motions. The vessel is considered as a two-degree-of-freedom system and the equations of motion in sway and roll are formulated in the time domain using an impulse response technique. Formulation of the problem of describing the flow of the deck water leads to a nonlinear hyperbolic system of equations. An approximate solution to these equations is obtained numerically using the random-choice method, also known as Glimm's method. From this solution the static and dynamic forces exerted on the vessel by the deck water are computed. These forces are then added to the external wave exciting forces to obtain a complete time-domain solution for the motion of the vessel and the deck water. We examine the effect of several simple changes in ship geometry. In most cases the deck water is found to act as a rather effective roll-damping mechanism. This is a result of the frequent appearance of hydraulic jumps which act as energy dissipators. The greatest reduction in roll was achieved by adding a small amount of camber to the deck. Variations in scupper geometry did not have very great effects on the rolling motion.
Predicting Hydrodynamic Behavior of Small-Waterplane-Area Twin-Hull Ships
Authors: Numata Edward
Published: January 2021

Existing naval and commercial small-waterplane-area, twin-hull (SWATH) vessels are described along with the reasons for choosing this type of hull configuration. The effects of changes in hull form and proportions on smooth water resistance and motions in rough water are examined. Analytical and experimental techniques presently available for use in the design process are discussed. Simple relationships for use in predicting resistance and seakeeping behavior in early stages of design are presented.
Optimization of Segregated Ballast Distribution and Its Impact on Tanker Economics
Authors: Czimmek D. W. , Jordan C. R.
Published: January 2021

The Intergovernmental Maritime Consultative Organization in 1973 proposed requirements for segregated ballast in an effort to eliminate pollution originated by ballast operations of tankers and possibly to reduce pollution caused by tanker accidents. The most cost-effective application of these pollution abatement measures for tankers is the subject of this paper. An existing very large crude carrier (VLCC) was used as the base ship for the studies on which the paper is based. An optimization procedure for the distribution of segregated ballast within the cargo box for three basic concepts is outlined in the first part of the paper; the determination of an optimum construction concept is described in the second. The optimum concept is derived from a comparison of ship economics. An economic evaluation for the conversion of the existing VLCC by modifying overall dimensions is presented in the third part. Also, a brief study of the economics for jumboizing the final tankers is included in Appendix 2. The purpose of the paper is to enhance capital savings with the utilization of cost-effective tank arrangements for conversions and new constructions, as proposed in Part 1. The economic studies of Parts 2 and 3 should assist an owner in his decision as to which construction concept to employ for a major conversion of an existing vessel or for a new vessel.
Planning and Scheduling Hull Production Operations
Authors: Ruehsen H. J.
Published: January 2021

Many factors determine how productive or, in comparison with other shipbuilders, how competitive a shipyard is. Among those, the manner in which a project is planned is one of great influence. The purpose of this paper is to bring forth those elements in the planning process that are believed to play the most important roles in achieving management control over project cost and timely completion. The scope of this paper is limited to the planning and scheduling of hull production operations. Although somewhere hull production and outfitting come together, it is felt that a separate discussion is appropriate since ready-for-outfitting dates must first be met in the hull production area. The planning and scheduling operations described begin generally with the award of a new contract or possibly sometime before that, if management strongly anticipates getting the work.
A Computer System to Derive Developable Hull Surfaces and Tables of Offsets
Authors: Clements John C.
Published: January 2021

The fairbody, chine and sheer lines of a proposed vessel are represented by cubic spline functions. Between each pair of chine lines that ruled surface is generated which has the same tangent plane at all points of each generator or ruling line. A procedure based on the multiconic development of a surface is used to modify the given chine lines to ensure that no ruling lines intersect at a point within the surface. The result is a developable hull surface. A simple method is suggested for fairing the modified chine lines and the steps necessary to generate tables of offsets from ruling-line intercepts are outlined briefly.
Shaft Alignment Using Strain Gages
Authors: Forrest Albert W. , Labasky Richard F.
Published: January 2021

A detailed description of the strain-gage shaft alignment procedure is presented, including a comparison between bearing reactions obtained using strain gages and hydraulic jacking. The various gage configurations available for measuring bending moments are discussed and estimates of the resulting error in bending moment are given. A simplified procedure is presented to calculate bearing reactions from the measured moments. Gage site requirements to produce a determinate system are established and a method is outlined to establish bearing reaction error bounds for a combination of gage configurations and sites.
The Sea Bus Story, Part 1: History, Design, Construction, and Operation of a Marine Rapid-Transit System
Authors: Case John Nelson
Published: January 2021

Sea Bus is a mass marine transit system designed in preference to a fixed structure across a 1.75-nautical mile body of water. The floating terminals of bonded post-tensioned concrete are designed to accommodate an extreme tidal range of 17 ft. They are E-shaped with two slips per terminal. The aluminum passenger vessels are double-ended catamarans powered by four steering right-angle drives placed at the ends of each demihull. These power units extend through the keel. The 400 passengers on the ships disembark and 400 more come aboard simultaneously through 12 sets of matching ship-terminal doors. The loading-unloading operation takes about 40 sec. Operation with two vessels over 31/4 years (17 June 1977 to 17 Sept 1980) has indicated an extremely reliable operation with a mechanical dispatch reliability of greater than 0.999. The worldwide market for energy, labor, and capital-efficient mass marine transit systems to replace bridges and tunnels which merely promote energy, labor, and capital waste is staggering. Sea Bus as is, and in modifiable form, is applicable in many of these potential world market areas.
Evaluation of Concepts for Improved Controllability of Tank Vessels
Authors: Miller E. , Ankudinov V. , Ternes T.
Published: January 2021

There is interest in the potential for reducing tank vessel collision, ramming and grounding (CRG) casualties by improving the inherent controllability of the vessel. This paper reports on studies conducted for the Maritime Administration in which various concepts for improving the controllability of tank vessels were investigated. A detailed study of U.S. Coast Guard tanker CRG casualty data and reports covering a five-year period was carried out to determine typical casualty situations and to make an initial assessment of the potential effects of improved controllability. From this effort, various measures of controllability were identified. In order to determine the performance of various concepts, studies with a baseline ship of about 84 000 dwt were carried out. The mathematical models used were based on model tests and analysis of information in the literature. The concepts investigated included a conventional single propeller/rudder configuration as a baseline and modifications to this baseline, including twin propeller/rudders, increased astern power, thrusters, high-lift rudders and thrust vectoring devices. The maneuvering performance was determined from evaluation maneuvers in shallow water, including turns, accelerating turns, coasting turns and stops. Some of the high-lift rudder and thrust vectoring devices were identified as having significant benefits. Suggestions for future efforts are presented.
Low-Frequency Dynamics of Moored Vessels
Authors: Oppenheim B. W. , Wilson P.A
Published: January 2021

Three complete theories of the low-frequency dynamics of ships and disks moored with multileg mooring systems in deep water are derived, evaluated, and computerized. One theory is nonlinear; it includes the effects of cubic damping, nonlinear mooring forces and the excitation-yaw motion feedback, and it is handled by simulation. It yields random, regular and transient records, probabilities and statistics, exact and linearized transfer functions, and spectra of responses. The second theory is linear, solved in the frequency domain. The third is a static theory, which is a by-product of the linear one. Mooring lines of arbitrary compositions are considered.
A Synthesis of Aluminum Crewboat Structural Design
Authors: Henrickson William A. , Spencer John S.
Published: January 2021

The need exists for a simplified structural review guide to enable U.S. Coast Guard marine inspectors to verify the structural adequacy of aluminum crewboats. The authors have developed such a guide. Typical existing crewboat forms and service speeds have been used to reduce the determination of impact pressures to a function of length and displacement. A design stress limit for the cyclic loading of the bottom structure has been determined based on wave observation data. Plating design has been verified by a comparison of sizing by beam theory versus elastoplastic analysis. A simplified grillage analysis has been used to determine the level of support provided by longitudinal plate girders or keelsons. A worked example and tables of section moduli for typical extrusions attached to plating are included as appendices.
Experience with Heavy Fuel
Authors: Mori Shigeo
Published: January 2021

Beginning in the fall of 1973, the oil crisis created a drastic worldwide change in thinking about oil resources. At the June 1979 OPEC meeting in Geneva, the price of oil was raised substantially, to some 20 U.S. dollars per barrel, and further forecasted to zoom up to more than 30 U.S. dollars in 1980. According to our study of a 10 000-dwt cargo vessel, the fuel oil cost—even in 1976—already constituted approximately 50 to 60 percent of the overall operating cost (excluding capital costs). In order to combat this undesirable development, the marine diesel engine is strongly needed to materialize energy savings from every possible angle, and various measures for this purpose have been vigorously advanced. One approach is the use of heavy fuel instead of the more expensive diesel oil, and this paper introduces one company's experiences with this energy-saving method, especially in the following items:Heavy fuel limitations— engine types suitable to burn up to 1500 sec and UE engines up to 3500 sec;engine room fuel system and accessories needed for up to 1500 sec and those for up to 3500 sec;problems still being encountered with heavy fuel;maintenance intervals and wear factors compared with running on diesel fuel; andoperation cost savings.

Finally, an example is given of a slow-speed diesel versus a medium-speed twin engine installation for a pusher tug of less than 300 G/T (tug/barge system).
Chemical Waste Incinerator Ships: The Interagency Program to Develop a Capability in the United States
Authors: Chapman Gerald O. , Leubecker Daniel W. , Martinez Lissa A. , Matthews Rosalie T. , Oberacker Donald A. , Wybenga Frits
Published: January 2021

In February 1980, an interagency work group undertook a study of at-sea incineration and the alternatives available to the Federal Government for encouraging the design, construction, and operation of U.S.-flag incinerator ships. The group examined previous incineration operations, various federal assistance programs, safety and control measures, incinerator ship conceptual designs, environmental impacts, and waterfront facilities. In September 1980, the work group concluded that chemical waste incineration at sea aboard specially designed and equipped vessels is a cost-effective, technically efficient, and environmentally acceptable technology for destroying many combustible hazardous wastes. The work group was expanded, designated the Interagency Review Board for the Chemical Waste Incinerator Ship Program, and now coordinates and expedites all Federal Government activities related to developing an incineration at sea capability in the United States. This paper presents the findings of the work group and the work program which the Interagency Review Board has initiated. Important ship design factors, such as the regulatory requirements, incinerator technologies, and incinerator system research recommendations, are explained. Details of a conceptual dual-mission ship design, which can incinerate both liquid wastes and solid wastes, are given. Anticipated operations permits, environmental monitoring, vessel design requirements, and waterfront facilities are discussed.