bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of the NFR‐90
Authors: SCHAFFER ROGER L. , KLOEHN HARVEY G. 
Published: March 2009

ABSTRACTThe NATO Frigate Replacement for the 1990s (NFR‐90) Project was a unique approach to naval ship design and acquisition. It would have been the first U.S. Navy surface combatant primarily designed by an international organization. As a planning scenario, up to 60 ships, including 18 for the U.S. Navy, were to be acquired by the eight participating nations, making it potentially the largest NATO project ever attempted. Approximately 1,000 man years over a 10‐year period were invested in the project.The project was prematurely terminated in January 1990. Nevertheless, a significant amount of work had been completed; the basic design of the ship was firmly established by a preliminary design, the combat system was thoroughly studied, and the economics of the program were well established. This paper describes the project, the technical aspects of the ship and combat system design, its innovative features and significant economic advantages.The conclusions relative to Aegis vs. NFR‐90 or NFR‐90/Aegis mix (Table 14) are the opinions of the authors and the estimates of associated costs have not been validated by the Naval Sea Systems Command.
Readiness Based Sparing (RBS): From Concept Exploration to Full Scale Development
Authors: BURDICK LENNY 
Published: March 2009

ABSTRACTThe actual implementation of a major acquisition program undertaken by the Navy is the result of successfully completing each of four critical acquisition phases: concept exploration, demonstration & validation, full scale development, and production/deployment.“Readiness Based Sparing (RBS) — The Process” must also successfully pass through these critical phases prior to implementation and institutionalization. Having successfully completed the Concept Exploration and Demonstration & Validation phases (which spanned Fiscal years 1979–1987), Navy has directed Full Scale Development of RBS — The Process for the DDG‐51 Class of ships beginning with the DDG‐52 as the prototype.The Full Scale Development effort, which began in July 1988, involves prototyping the sparing of the entire DDG‐52 platform to readiness objectives within a funding constraint and the evolution of a total process which ensures that resources can be linked to readiness at the platform level for all new construction ships. A joint NavSea/NavSup Working Group and a Flag Steering Board have been established to implement and monitor the application of RBS — The Process on DDG‐52. To date, significant progress has been made in the areas of data collection/correlation, RBD development, identification of design support constraints and readiness drivers, assignment of preliminary Ao thresholds, improving data quality and increased communication between the engineering and logistics communities.The progress which has been made to date provides a formidable foundation, which we must continue to strengthen, as we move toward the Production/Deployment phase of RBS —The Process.
Performance of an Omnidirectional Wheel on Snow and Ice
Authors: BLAISDELL GEORGE L. 
Published: March 2009

ABSTRACTA brief study was performed to investigate the suitability of service vehicles equipped with a unique omnidirectional wheel operating aboard aircraft carriers in northern latitudes, where ice and snow on flight decks is not uncommon. This study addressed the comparative performance of the omnidirectional wheel, a bias‐ply highway tire as used on current Navy MD‐3 aircraft tow vehicles, a typical nonpneumatic forklift truck tire, and an automotive radial‐ply all‐season tire. The tires were tested for driving traction levels on prepared ice, hard‐packed snow, and fresh shallow snow. In general, the omnidirectional wheel showed performance superior to the forklift truck tire and the bias‐ply highway tire. The radial all‐season tire, however, outperformed the omnidirectional wheel in traction on slippery surfaces. The omnidirectional wheel was found to be well‐behaved during traction testing and shows promise for operation on winter surfaces. Recommendations are provided that might further improve omnidirectional wheel performance on snow and ice.
Hydrodynamic Efficiency Improvements for U.S. Navy Ships
Authors: McCALLUM DONALD , ENGLE ALLEN H. , PLATZER GREGORY P. , KARAFIATH GABOR 
Published: March 2009

ABSTRACTThis paper reports on an investigation of the applicability of recent hull efficiency improvement concepts to U.S. Navy ships. Among the concepts investigated were stern flaps, Grim Wheels, alternate aftbody configurations, bulbous bows, and flow modifying ducts. Extensive model testing was conducted at the David Taylor Research Center (DTRC) for each concept, and care was taken to check out critical propeller cavitation and noise aspects associated with the investigation of alternate stern configurations and Grim Wheel concepts. A guiding principle in this program was to utilize the expertise available both here and abroad so that each design concept would have the greatest chance of success.As a result of these investigations, significant gains in fuel economy were obtained. Specifically, full scale trials of FFG‐25 (USS Copeland), equipped with and without a stern flap, demonstrated that fuel savings of 5–9% are achieved at speeds above 12 knots. In addition, fuel savings of 9.4% for T‐AGS 39 equipped with a Grim Wheel and 5.6% for the combination of a large bulbous bow and a large diameter/ low RPM propeller on AE‐36 have been predicted. The paper concludes with a direction for future applications to U.S. Navy, and other ships.
Development of a Lithium Rechargeable Battery for Underwater Vehicle Propulsion
Authors: SMITH PATRICIA H. , CHUA DAVID L. , JAMES STANLEY D. 
Published: March 2009

ABSTRACTThe Navy is researching lithium rechargeable batteries as a possible replacement for silver oxide/zinc cells in powering the next generation of naval underwater vehicles. This paper summarizes progress made with the most promising lithium system — lithium/cobalt oxide, which has 2.5 times the theoretical energy density of silver oxide/zinc.Using small (0.03 Ah) laboratory cells, optimization was completed for cathode fabrication and electrolyte composition. Even at three times the required discharge rate, cycle life obtained with these cells was over double the program goal. Furthermore, a significant fast charge capability was demonstrated when charging was conducted at constant potential versus constant current. This laboratory cell technology was scaled up successfully to 2.5 Ah cell test fixtures. Presently, engineering development is underway at the 10 Ah level in hermetically sealed, instrumented subcells. Preliminary data are achieving the required energy densities for at least 15 cycles with tests still continuing. The optimized design resulting from the 10 Ah tests is being incorporated into 30 Ah cells.
Role of Simulation in Rapid Prototyping for Concept Development
Authors: KING JOSEPH F. , BARTON DOUGLAS E. 
Published: March 2009

ABSTRACTA valuable technique during concept development is rapid prototyping of software for key design components. This approach is particularly useful when the optimum de sign approach is not readily apparent or several known alternatives need to be rapidly evaluated. A problem inherent in rapid prototyping is the lack of a “target system” with which to interface. Some alternatives are to develop test driver libraries, integrate the prototype with an existing working simulator, or build one for the specific problem.This paper presents a unique approach to concept development using rapid prototyping for concept development and scenario‐based simulation for concept verification. The rapid prototyping environment, derived from artificial intelligence technology, is based on a blackboard architecture. The rapid prototype simulation capability is provided through an object‐oriented modeling environment. It is shown how both simulation and blackboard technologies are used collectively to rapidly gain insight into a tenacious problem. A specific example will be discussed where this approach was used to evolve the logic of a mission controller for an autonomous underwater vehicle.
Applying Vector Processing to Active Sonars for Increased Accuracy and an Expanded Operating Envelope
Authors: WHITNEY DAVID A. , BENEDICT TERRY J. 
Published: March 2009

ABSTRACTAdvanced computing technology development now allows considerable computational power to be packaged in small, modular components for low costs. In particular, vector and array processor add‐on boards offer a way to incorporate modern parallel capabilities into existing hardware systems. In addition to cost efficiency, the fact that these boards may be able to plug‐in to existing computer systems provides both design flexibility and a more rapid way of upgrading deployed computer hardware. To take advantage of such processing capabilities, however, algorithm analysis must be performed to determine what functions can be efficiently off‐loaded to the vector processing board, and to decide what parts of the original serial algorithm should be redesigned to take advantage of the new hardware architecture.This paper presents a case study of how these issues are being addressed in a real‐time active sonar data processing system. Vector processing technologies are being analyzed for application to correlation sonar systems used for estimating ship velocity on submarines, surface ships, and autonomous underwater vehicles. Such a system is deployed on Trident II SSBNs and is meeting its current design objectives. However, real‐time operation of the correlation sonar is computationally intensive and fully utilizes the processing power of the fielded computing hardware. Expansions in the accuracy and operating envelope of the system are desirable and are not limited by the physics or practical operation of the sonar system, but rather by the speed at which processing of hydrophone returns can be performed. This analytic feasibility study investigates the possibility of expanding the operating envelope through the use of vector processing technology, within the constraint that any hardware or software changes would have minimal impact on the deployed system. It is predicted that significant speedups and operating envelope expansions can be achieved by introducing vectorized hardware and algorithms into the existing scalar system.
Engineered Approach to Effective Maintenance Management
Authors: CIERI ANTHONY M. , ELFONT MARK M. 
Published: March 2009

ABSTRACTThe Assessment of Equipment Condition (AEC) Program at the Naval Ship Systems Engineering Station has been providing shore based support to assess the condition of shipboard equipment. This paper examines some of the limitations of the existing process. The paper offers an engineered approach to provide condition assessment on board ship and the shore side support necessary to maximize the effectiveness of the total ship maintenance process. The recommended approach uses existing technology and current hardware and software applications. Included in the approach is the use of microcomputer machinery work stations with expert system software, and a central Condition Maintenance Information System with the capability to provide work packages based on condition assessment and to trend the effectiveness of maintenance decisions. The paper identifies a phased implementation with a limited pilot program prior to fleet wide involvement.
New Techniques in Weapon Firing Cutout Zone Design
Authors: GEORGE EVERETT 
Published: March 2009

ABSTRACTWeapon pointing and firing zones are critical operational parameters which directly affect the safety and capability of weapon performance and ship mission. These zones are normally implemented in the weapon system and restrict areas of weapon movement and function allowing clearance for ship structure during weapon performance. The primary purpose of the zones is to ensure topside safety by preventing the weapon from firing into surrounding ship structure. Weapon pointing and firing zones are also used to integrate weapon and other shipboard equipment functions to avoid interference conflicts.The Naval Surface Warfare Center (NAVSWC) is the technical direction agent which designs weapon pointing and firing zones for every large caliber gun mount and rotating missile launcher on U.S. Navy ships. Because of the increasing complexity of topside operations and applications in computer technology, new methods are being developed to support NAVSWC weapon zone design efforts.This paper first summarizes present techniques in NAVSWC weapon zone analysis and design. The second part of the paper describes methods under development using graphic computer systems to conduct safety analyses for weapon zone design. The paper concludes with a review of future weapon cutout system improvements.
Total Quality Management and its Application to F‐14 Depot Maintenance
Authors: ROBBINS THOMAS , SHEN TERRY W.T. , WILBAT BRUCE B. 
Published: March 2009

ABSTRACTUnderstanding the concepts of quality costs through the reduction of waste and process variation is fundamental to the TQM philosophy. The evolution in U.S. quality control demands a shift from the traditional method of auditing the finished product and improving quality by fixing problems to a method of auditing processes. Likewise, TQM demands proper use of statistical process control and continuous training of management and the work force to ensure continuous improvement and productivity.This paper discusses how the Naval Aviation Depot (NADEP) Norfolk, Virginia, as an example of U.S. industry, employed the new management philosophy of TQM to reduce costs and boost productivity and efficiency. A specific application of TQM is highlighted with the preparation and implementation of the F‐14 aircraft maintenance competition program. As part of this effort, the Norfolk depot's challenge was to streamline operations to minimize the cost of scheduled maintenance on a delivered F‐14, while simultaneously maintaining quality. The competition against private industry for the aircraft workload provided unique opportunities to use TQM to make cultural changes throughout the depot. Norfolk would demonstrate that quality products are more a function of employee knowledge and interaction than the application of traditional quality control technology.
Improving the Ship Design, Acquisition and Construction Process
Authors: RYAN J. CHRISTOPHER , JONS OTTO P. 
Published: March 2009

ABSTRACTIn the spring of 1990, the NavSea Chief Engineer initiated a project to improve the design, acquisition and construction (DAC) of U.S. Navy ships. The project's objectives are to reduce the time and cost of acquiring and operating Navy ships while improving their quality. unlike previous studies on the subject, the project utilizes a rigorous process analysis approach and attempts to use quantitative measures as the basis for recommending improvements.The paper is, of necessity, a status report on the progress of this project. Topics covered include: the DAC process; a look at the current state of ship acquisition time, cost, and quality; the methodology for process improvements; and early findings.
VSCF Cycloconverter Ships Service Power Equipment
Authors: HULTGREN KENNETH J. 
Published: March 2009

ABSTRACTPropulsion derived ships service (PDSS) power systems offer significant potential savings to the Navy by eliminating the need for independent diesel and gas turbine‐generator sets to produce ships service power. With PDSS, both the propulsion system and generator are driven by the main engine(s) to reduce fuel consumption, equipment weight and space, and maintenance costs.Shaft driven power takeoff (PTO) ship systems have been the forerunners of PDSS on commercial vessels, but the Navy's more stringent requirements for wide speed range and high power quality are beyond PTO's limited capabilities. Newer technologies are needed that are more versatile. This paper concentrates on the high frequency generator/cycloconverter (HFG/CCV) based variable speed constant frequency (VSCF) system, which brings inherent advantages to PDSS application. These include additional savings in size and weight via use of compact high frequency equipment, a wide electrical speed range, and stable, clean DoD‐Std‐1399 Type I ships power.HFG/CCV‐based systems up to 3000 kW capacity over a 3‐to‐1 electrical speed range are described, as are alternative PDSS hybrid systems where a speed range expander gear is employed. This enables the use of either smaller, narrow range PDSS equipment, or wider propulsion ranges between PDSS beyond 3‐to‐1. PDSS equipment layout drawings are included for engine room evaluation, along with a detailed weight and space comparison between PDSS, a T‐AO 187 PTO System, a stand‐alone gas turbine generator set, and a diesel turbine‐generator set to show the savings that can be achieved by HFG/CCV‐based PDSS systems.
Electronic Warfare Testing Utilizing an Improved AN/ULM‐4 Test Range
Authors: WHITE LAWRENCE C. 
Published: March 2009

ABSTRACTElectronic warfare (EW) systems aboard surface ships have become increasingly complex and currently face multiple simultaneous threats. The primary shipboard EW system in the United States Navy is the AN/SLQ‐32 system, which is designed to provide detection and active jamming against incoming missile threats. The AN/ULM‐4 test range has been utilized to conduct operational readiness testing of this system for many years. Numerous deficiencies of the AN/ULM‐4 have been identified and documented.The complexity of current EW systems has demanded that the capabilities of the AN/ULM‐4 test range be significantly improved. The redesign of the AN/ULM‐4 to correct these deficiencies is presented. This redesign represents a significant increase in test range capability which has been debated and discussed for over ten years. Particular attention is paid to effects certain design constraints had on the decision making process during the course of the redesign.
Royal Australian Navy Readiness Based Sparing
Authors: SANDERS REGINALD 
Published: March 2009

ABSTRACTIn 1985, the Royal Australian Navy made a commitment to using readiness based sparing in support of their Seahawk project For the first time, sparing decisions at all supply locations were to be determined simultaneously with a single focus on equipment readiness. To meet this challenge, an advanced readiness sparing model was designed and developed. In addition to a robust multi‐echelon/multi‐indenture capability, the model was fitted with many new and unique features. For example, it recognized commonality of parts not only within an aircraft configuration but also across different aircraft types with common supply support. It allowed for variable operating tempos and readiness goals for deployed and non‐deployed aircraft, and it provided a supply and maintenance representation flexible enough to accurately model the RAN's real world support structure.
Structural Reliability Assessment with Ambiguity and Vagueness in Failure
Authors: AYYUB BILAL M. , LAI KWAN‐LING 
Published: March 2009

ABSTRACTEngineering projects and designs are commonly developed in a systems framework that includes different types of uncertainty. In general, uncertainty can be of either the ambiguity or vagueness type. The theory of probability and statistics has been extensively used in engineering to deal with the ambiguity type of uncertainty. The theory of fuzzy sets and systems has been used to model the vagueness type of uncertainty in many engineering applications. In this paper, the role of fuzzy sets in engineering systems is described using a selected example area that deals with vagueness in failure definition as used in solving structural reliability problems. The reliability of a structure is commonly based on an explicit definition of failure, making structural reliability dependent on this definition. The vagueness in the perception of damage and failure introduces another class of uncertainty, in addition to the commonly realized and modeled class of uncertainty, i.e., ambiguity. In this study, a methodology for reliability assessment of structures based on a fuzzy definition of failure is developed. The significance of the contribution is in providing the reliability of the structure over a damage spectrum.
Propulsion Powered Electric Guns: A Comparison of Power System Architectures
Authors: DOYLE TIMOTHY J. , GRATER GUY F. 
Published: March 2009

ABSTRACTAlternative power system architectures and interface technologies for driving high energy pulsed loads from the propulsion equipment of surface combatants are compared. Gas turbine mechanical and gas turbine Integrated Electric Drive (IED) propulsion trains are considered as prime power sources. Focus is on the energy path between the ship's prime power and the pulsed load, comparing system candidates on a size, weight and component cost basis. A capacitor based Pulse Forming Network (PFN) supplying an Electro‐Thermal (ET) Gun is utilized as the common load for all configurations. Results indicate that dedicated auxiliary generators driven from propulsion gas turbine engines is the preferred method of powering electric gun PFNs from ship drivetrain equipment. Auxiliary generator‐based systems are compact and lightweight over a wide power range, are equally attractive with both electric and mechanical drive trains and demonstrate retrofit potential to the current fleet.
A Methodology for Evaluation of Ship Fire Safety
Authors: SPRAGUE CHESTER M. , RICHARDS ROBERT C. , BLANCHARD LCDR. MARC A. 
Published: March 2009

ABSTRACTThe overall fire safety of a ship is not obvious. It is dependent on many factors including the vast number of fire scenarios that are possible. A means is required to evaluate a ship for the many types of fires it may be subjected to. The analysis should show what would happen if various alternatives such as protected cable trays, better fire boundaries, or improved fire detection had been used. The Ship Fire Safety Engineering Methodology (SFSEM) provides an integrated framework for analyzing fires on ships in comparison to established fire safety objectives. It accounts for all relevant aspects; the behavior of fire, the effectiveness of passive design features, automated suppression systems, barrier materials, flame spread paths, and manual firefighting.The Ship Applied Fire Engineering (SAFE) computer programs implement SFSEM and evaluate the probability of spaces and barriers limiting a fire. The evaluation is conducted on a compartment‐by‐compartment basis. It incorporates the fire growth hazard with the probabilities of ignition, automated fire suppression, manual fire suppression, and barrier effectiveness. SAFE calculates the probable paths of fire spread based on time durations. SFSEM/SAFE has been used successfully in a design application and in a retrofit situation.