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Minding the Helm: Marine Navigation and Piloting (1994)

Chapter: NAVIGATION AND PILOTING TECHNOLOGY

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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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Suggested Citation:"NAVIGATION AND PILOTING TECHNOLOGY." National Research Council. 1994. Minding the Helm: Marine Navigation and Piloting. Washington, DC: The National Academies Press. doi: 10.17226/2055.
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6 Navigation and Piloting Technology SUMMARY A broad range of vessel- and shore-based technologies are emerging that have considerable potential for improving navigation safety. The effective applica- tion of high technology in operations and professional development programs offers a substantial means to significantly reduce risk in the near term. Interna- tional technical and performance standards and criteria, and corresponding na- tional standards and criteria are needed to guide the systematic introduction of new navigation technologies with capabilities and configurations that are well designed to enhance navigation safety. Technology is an important component of an overall approach for solving safety issues confronting marine transportation. To achieve the full potential of advanced technology for improving safety, sys- temic factors will need to be comprehensively addressed including ( 1 ) operator qualifications and training, (2) manning, (3) pilotage, (4) systems maintenance, (5) regional variations in port and waterway operating environments, (6) economics, and (7) institutional policies. Successful application and effective use of new and innovative technolo- gies require validation of the technologies, changes in operational procedures, and operator training. These efforts are necessary not only to ensure suitability and reliability of complex and integrated systems but also to demonstrate the practical value of these systems to mariners. Validation methods for navigation technologies that rely on software are not fully developed; there are few proven methodologies that offset the need for extensive field trials in the full range of operating conditions in which these technologies will be applied. Reliability as 217

218 MINDING THE HELM sessment techniques using statistical models are not mature for determining sys- tem faults in software-dependent systems. Further, although the capability to tailor visual presentations of navigation data can be a powerful tool, it also has the potential to increase risl<. For example, important navigation information could be screened out of the display if system designers or users lacl<ed full appreciation of information needs across an entire transit or if there were no safeguards in design or operating practices to prevent this from happening. Apart from being time consuming, the traditional method of validating technology through trial and error during actual operations can expose a vessel to danger. Moreover, this method lacks adequate controls, monitoring, and eval- uation regimes to ascertain technology reliability. At-sea use of navigation tech- nology does not prove system effectiveness for ports and waterways applications due to differences in operating conditions and operational requirements. Indeed, error-free performance of technical systems at sea can lead to premature confi- dence and trust in their capabilities for use in pilotage waters. The ever-expanding variety of navigation technologies multiplies the de- mands on marine pilots, who ideally would be l<nowledgeable and sl<illed across the entire technological spectrum. Similar demands are placed on docl<ing mas- ters, especially those providing harbor pilotage services. Although marine pilots could not possibly become familiar with every technological permutation, their knowledge and sl<ills are valuable resources that could be effectively applied in validating new navigation technologies. As technology solves one set of problems, others may be created. A requirement for specific electronic precision navigation equipment may or may not achieve the intended results in actual operations, depending upon system capabilities, the operating conditions in which applied, and mariner acceptance of and proficiency in using the technology. Further, legal or regulatory mandates for a specific technology could constrain development of other electronic navigation systems and associated benefits; other navigation technologies, marine traffic regulation, or enhancement of pilot professional qualifications (perhaps through vessel- or area-specific training or shiphandling simulation) could prove to be better alternatives for improved safety in certain operating conditions. Histori- cally, once in general application in commercial operations, technology rarely has been formally or scientifically assessed for effectiveness to establish a basis for refinements and further applications. Concern over creating new problems be- comes more critical if technological advances have been dramatic enough to warrant new professional requirements for operators or if a technology pre- cludes or inhibits human intervention to override automated systems, for exam- ple, when needed to overcome system malfunction. The mariner's traditional conservative approach to change is understand- able in view of concerns over the need to establish confidence in system perfor- mance for ports and waterways applications and the need for training in system operation. However, the desirability of reducing operational, economic, and en

NAVIGATING AND PILOTING TECHNOLOGY 219 vironmental risl<s nevertheless argues for accelerated introduction, validation, acceptance, and prudent use of high-technology navigation systems. INTRODUCTION High-technology navigation systems have matured to the point where, if used wisely and adequately supported, they have the potential to enhance mari- time safety and transit efficiency significantly. Satellite technology such as the Global Positioning System (GPS), for example, can provide continuous and very accurate position fixing that can support both navigation and operational sched- uling. Advances in electronic charting and bridge automation can reduce the need for manual processing while facilitating the interpretation and optimal use of navigation information. The application of expert systems can offer support for decision making and for overcoming human error. These and other advanced technologies could help masters, marine pilots, and ship's conning officers cope with a variety of long-standing navigation and piloting difficulties as well as certain factors that can affect visibility or maneuverability on large modern ships. These problems include impaired visibility from the bridge; large wind-catch areas; and the propensity to maintain momentum for long distances, particularly for loaded tankers. The dual nature of navigation technology great potential balanced by seri- ous potential pitfalls is emphasized throughout this chapter, which examines options for enhancing safety by improving technology. The committee views technology as a powerful means for improving safety, but not as a panacea for the safety dilemmas confronting the maritime industry. In the marine transporta- tion sector, technology application is approached from different perspectives and driven by differing needs economics, safety (operational, public, or environ- mental), assigned missions, or a combination of these. Sometimes these needs point to the same technological solution, but the relationship among them is not always obvious. Also not always obvious is the potential economic benefit of emerging technologies to operating companies. The chapter outlines how mariners currently use technology and explores possibilities for further technology development. Options for incremental and strategic improvements are presented. The chapter concludes with an overview of how navigation technology is adopted in the maritime world and the implica- tions of this process. Short descriptions of navigation and piloting equipment and the traditional ship-bridge design are provided in Appendix G. SUMMARY OF IMPROVEMENT OPTIONS The improvement options identified in this chapter are summarized in Table 6-1. Although not an exhaustive list, the summary provides the committee's estimate of the time frame in which improvements might be made in each area.

220 TABLE 6-1 Summary of Technology Improvement Options MINDING THE HELM Category/ Option Immediate Near-term Long-term Action Action Action PASSAGE PLANNING · Develop international standards for electronic charts Develop international standards for electronic chart systems Develop international standards for automated chart corrections Require electronic charting systems to meet international standards Provide electronic chart data bases by or through national hydrographic offices Conduct more timely and complete hydrographic surveys Develop automated systems for chart corrections Provide accurate, timely reports on environmental conditions Expand real-time environmental information systems POSITION FIXING . . . . x x Develop minimum international standards for Electronic Chart and Display Information Systems (ECDIS) Indemnify from liability providers of electronic charts and manufacturers ot:^ electronic chart systems Review and if necessary revise laws x and regulations for bridge team operations Retain paper charts as a backup for ECDIS Improve accuracy of short range aids to navigation Improve positioning of buoys and fixed aids Expand distribution of racons and high-intensity lighted ranges Develop and install electronic ranges for poor visibility conditions Accelerate implementation of GPS and DGPS Accelerate development of electronic charts Accelerate schedule for harbor surveys Increase attention to human factors aspects of ECDIS Develop long-range plans for improving aids to navigation Review long-range plans for production of charts x x x x x x x x x x x x x x x x x

NAVIGATING AND PILOTING TECHNOLOGY TABLE 6-1 (Continued) 221 Category/ Option Immediate Near-term Long-term Action Action Action COMMUNICATIONS · Aggressively enforce VHF radio regulations · Improve Vessel Traffic Service (VTS) communications procedures to reduce potential for human error Implement more efficient data communication in VTS-user interactions Improve radio circuit discipline, including institution of standardized vocabulary Create additional VHF channels for commercial users Improve radio bandwidth efficiency . . COLLISION AVOIDANCE AND SURVEILLANCE · Develop new Automatic Radar Plotting Aid (ARPA) functions and display . . capabilities Review, revise international ARPA standards to permit use of alternative technologies for speed measurement Standardize data outputs from integrated systems Adapt low-light video and sound discrimination systems for marine use Increase use of advanced technologies such as automated dependent surveillance (ADS) in VTS operations where feasible Conduct comprehensive analysis of requirements for ADS data communications · Accelerate research of efficient data communications systems STEERING AND TRACK KEEPING · Improve autopilot algorithms for shallow-water maneuvering · Allow use of high-performance autopilots in pilotage waters Establish legal equivalency of ECDIS for plotting x x x x x x x x x x x x x x x x continued on next page

222 TABLE 6-1 (Continued) MINDING THE HELM Category/ Option Immediate Near-term Long-term Action Action Action . BRIDGE TEAM MANAGEMENT AND DECISION MAKING · Accelerate use of integrated navigation systems Develop more complete standards for NEMA 0183 Develop standards for interfacing bridge equipment, engineering systems, and cargo/ballast systems Develop international standards for alarms, displays, and controls used in Integrated Ship Control Systems (ISCS) Develop rules for bridge configuration of ISCS Redefine automated dependent surveillance (ADS) to develop a performance-based standard Conduct research and development to improve ADS to simplify integration and reduce cost Encourage development of portable communications and navigation systems (PCNS) · Develop piloting expert systems to support integrated bridge systems (IBS) and integrated ship control systems (ISCS) Develop expert systems for complex, busy waterways Conduct research and development to improve compatibility of expert systems with PCNS, IBS, and ISCS Dedicated radio frequencies for marine electronic data transmission Develop efficient and standard data protocols · Develop international standard for ADS Conduct risk assessments of integrated bridge operations and equipment Develop regulations allowing non traditional bridge team Review and amend manning laws and regulations . x x x x x x x x x x x x x x x x x

NAVIGATING AND PILOTING TECHNOLOGY TABLE 6-1 (Continued) Category/ Option Immediate Near-term Long-term Action Action Action WEATHER AND ENVIRONMENTAL MONITORING · Transmit PORTS data electronically for use with ECDIS Improve hull stress sensors and methods for mounting them · Extend PORTS system to provide service to all major U.S. harbors DOCKING EVOLUTIONS · Conduct research and development to hasten implementation of automated docking systems · Develop more-reliable winch-control systems x x x x x IMPROVING NAVIGATION TECHNOLOGIES A wide range of technological options for enhancing maritime safety was examined during the study. The analysis presented here is organized by naviga- tion and piloting function. Within each functional classification, the current state of practice is outlined, and options are identified for immediate action, incre- mental improvement, and long-term development of technologies. For purposes of clarity, the options are italicized in the text. Immediate-action items are those needed to guide the application of emerg- ing technologies. They deal principally with technical and performance objec- tives and standards. Incremental improvements were defined as those already under way or achievable in one to three years. Long-term development alterna- tives were those only now being proposed, those having an uncertain time hori- zon, or those requiring extensive international coordination or change to imple- ment. Such strategies would be slow to produce effects but would have the benefit of ensuring that the diverse elements of the maritime community worked together and had time to accept any changes. The functional classifications include: passage/route planning; . . i. . poslhon ilxlng; communications; collision avoidance and surveillance; steering and track keeping; bridge team management and decision making; 223

224 MINDING THE HELM weather and environment monitoring; and · docking evolutions. The analysis assumes some basic knowledge about each technology. This background is provided in Appendix I, which defines each technology men- tioned in this chapter and describes the traditional bridge setup, including place- ment of technologies. Several important off-ship technologies, including VTS systems and marine simulations used for waterway design and pilot training, are addressed in detail in Chapters 1, 3, and 5 and Appendix E. Passage/Route Planning Mariners plot their intended track line on a paper nautical chart showing waypoints for course and speed changes. The technologies used include tradi- tional nautical charts; navigation publications such as the Light List; and where available, electronic charting systems. Various technical and institutional factors constrain the full application of electronic charting technology. These include the lack of international perfor- mance standards (although these are under development), the unavailability of government-provided electronic charts or chart data, and the fact that the hydro- graphic data that are available for many pilotage waters are not as accurate as is the capability to determine precise positions using differential GPS (DGPS) and electronic charting systems. Further, the process of accumulating electronic data bases is slow and costly. Choosing the Charting Medium The choice of paper or electronic chart may be based on the relative advan- tages of the presentation format or the ease of use. (Paper and electronic charts also differ in legal status, an issue discussed later in this chapter.) Paper charts permit the user to see wide areas in sufficient detail to assist with voyage and route planning, and they can be folded and moved about the bridge to aid in visual orientation and identification of geographic features and aids to naviga- tion. They also remain available for use if an electronic charting system fails to operate correctly or becomes disabled. Whether all features of paper charts can be replaced by electronic charts has not been established (Gold, 1990a). Electronic charts, while capable of provid- ing the same or greater detail as paper charts over wide areas, must either con- dense this information into a smaller display or present only sections of charts (scaling factors as they affect accuracy are discussed later in this section). On the other hand, precise navigation data and radar images can be integrated into an electronic presentation to provide real-time steering guidance and hazard-avoid- ance features. Additionally, software-driven, computer-aided features can be de

NAVIGATING AND PILOTING TECHNOLOGY 225 signed to aid in data analysis and decision making. For example, color coding could be generated to mark depth contours. The master, pilot, or watch officer can determine what hydrographic data are displayed to aid in their transit. Criti- cal information needs vary from situation to situation. It is probably not neces- sary to display all information at all times. In fact, the most effective use of electronic chart display features appears to be selective display of information. However, an incomplete understanding of information needs for a transit or errors made in selecting what data are displayed could result in failure to display all key information needed at various locations along the vessel's route. What to display and when to display it are basic issues in determining whether Electronic Chart Display and Information Systems (ECDIS) can replace existing traditional equipment such as a separate radar console and paper charts. Empirical research is currently under way to assess which information in an ECDIS is most used, and which is most useful to the mariner (Smith, 1993~. These factors could complicate establishing use of electronic charts as legal- ly acceptable replacements for paper charts for planning and conducting naviga- tion. Performance criteria would need to address minimum display requirements for hydrographic data and ship parameters such as depth, breadth, and maneu- vering characteristics. In any case, it would be important for the mariner to be aware of which data will be displayed automatically and to what extent this data can be controlled by the user. Scaling Factors The scale of electronic chart displays needs to be constrained to ensure that chart data are not depicted at larger-than-intended scales, because the level of charted detail and the accuracy change with the scale of the chart. In general, the larger the scale and the smaller the area display, the more accurate the feature based on field survey standards and the precision with which data can be pre- sented. The standards for the horizontal accuracy of paper charts are based on the scale of the original field survey. Normally, the error budget for a chart is 0.8 mm at the scale of the survey. For a 1 :50,000-scale chart, features and soundings are thus required to be accurate to 40 m; for a 1:10,000-scale chart, 8 m. The scaling constraint undoubtedly will lead to demands for new, large-scale, highly accurate hydrographic surveys, especially of harbors and harbor approaches (Donald Florwick, NOAA, personal communication, October 30, 19923. It also may be useful to have software switches that change the level of detail to corre- spond to the scale presented on the electronic-chart visual display. Further, the hydrographic data need to be very accurate and reliable so that the mariner is not given a false sense of security, because the appearance of the high-technology display may be better than the data presented. Thus, even as electronic charting systems can offer unique additional sup- port for navigation functions other than voyage planning, they also have the

226 MINDING THE HELM potential to induce error through data screening features. Therefore, the federal agencies involved in development of standards for electronic charting systems are supporting the ECDIS concept. Only electronic charting systems that meet international performance standards including some minimal level of detail would carry the ECDIS designation and be considered to meet legal carriage requirements. Accuracy of Nautical Charts An electronic charting system, when combined with real-time position data conveys a convincing sense of reality. The visual presentation can be easily related to the maneuvering situation, facilitating the interpretation and applica- tion of displayed information. This capability appears to cause users familiar with system operation to believe the video display and to become increasingly reliant on it. Therefore, the information displayed needs to be as accurate as possible. Although electronic charting systems offer real-time utilization and increased precision in position fixing, and rapid update capability, the available hydro- graphic data upon which these features rely are incomplete (Box 6-11. Thus, the hydrographic data bases for electronic charts will not be any more reliable (in general) than those for paper charts in the near-term, because the same survey data are used. Because the accuracy of the available data is generally less than the precision by which the data can be displayed by an electronic charting sys- tem, mariners must consider the limitations of the data when using these sys- tems. Another accuracy factor is that NOAA has a substantial backlog of reported chart discrepancies that have yet to be resolved. The agency is capable of con- ducting field investigations of only about 20 percent of reported discrepancies each year. NOAA, which produces 1,000 different nautical charts, had almost 2,000 request for new surveys as of August 1993, some dating back to 1984, and 400 to 500 new wrecks and obstructions are reported annually for the East and Gulf coasts alone (NRC, 1994~. NOAA plans to make users aware of the limitations of nautical paper charts by adding source diagrams, which will show the date, source, and scale of the survey data (Prahl, 1992~. Knowledge of chart shortcomings will help users make informed decisions. But even greater demands will be placed on hydrogra- phers by the nature of electronic displays. The development of digital hydro- graphic data bases is the most labor-intensive and costly step in making electron- ic charts available to the mariner. The International Maritime Organization's (IMO) ECDIS Provisional Performance Standards require that data bases be supplied by a national hydrographic office. However, electronic chart data bases must be developed on an international scale to provide complete coverage and

<~ ~ ~ = ~227 I i! 1llllllllllIllil~l~llllIIlilIlIlllTITITTTTTTTTT~l~lllT 111 lIll~llllll~ll!lTll TT . i66.:cI1l~llA~.iph, 4:~vel Instill s~s~s~s~s~s~s~s:s~s~s~sss:.s.ss~ss.s.ss~ss.s.s.s ss~ss.s.ss~ss.s ..s~sS.ssssss~ss.sss.ss~ss.s.sss~ss~s~s~s~ssssss.sssssssssS~s~sss~sssssssssssssss~s~s~sssssssssssssssss~s~s~sssss~s, ,.ssssssss~sssssssss ~,ssS~sssssssssss~sssss~s~sssss~s~ssss I -~#l~=l~I~ Bulls - ~ it!!! 1 updated rogul~ly, and 1berc needs to be consistency iD units of measure) the process involves digidzing paper abbots and, idcaUy, conducing new bydro- graphic surveys using state-oPtbe-=t technology to provide 100 percent bottom coverage in SigDi5C8Dt gems. The data flats Id procedures to produce the data bases are in place,2 but digitizing paper charts of U.S. maters alone is ex 1Present NOAA cabs ma use Bee Elbows, or millers Conversion lo 1be metric system, now under may, is expected lo lie lO lo 13 yearn Thus, it is possible for a vessels echo sounders Ode gables, Ed nautical cabs lo be in Wee di~renl Unix. Electronic cuing systems need lo be camp of convening between ~1 these menses Ed displaying constant units. 2Tbere He Lao methods of digitizing dale. To produce raffler digLa1 dam, Me pier cab is passed Tough ~ scanner, whim captures ~ digital image. The raffler image can be displayed on a consular monitor but ilS Velures cannot be deleted or manipuIaled individually. An overlay for user input and cb=1 updates can be added. Vector dale, on 1bc oar hand, ~ produced by storing position and Bud on iron far each arc on 1hc char. Vector iron is more discuss Fan raster data to gather but oars 1hc bencA1 of scleclivc manipulation and display. Vector data is required far ECDIS. Elec~oMc cog ~spl~ can use either type of dam.

228 MINDING THE HELM peeled to take 5 to 10 years at today's rate of progress (Thomas W. Richards, NOAA, personal communication, April 30, 19931. A question is whether the features of electronic charting systems have suffi- cient value to justify their near-term adoption without a corresponding improve- ment in basic hydrographic survey data and timely resolution of chart discrepan- cies. Options for Immediate Action There are no universal standards that, if met, would ensure that all electronic chart display systems performed at acceptable levels. International standards could be developed for production, use, and updating of electronic charts; pro- duction and use of electronic chart display systems; and provision of automated corrections to electronic charts and other notices to mariners (see Sandvik, 1990~. In this regard, the current worldwide effort to evaluate the data standard for electronic charts, DX-90, is encouraging (Alexander and Black, 1993; Pendle- ton and Alper, 19921. Also, the IMO has promulgated provisional performance standards for ECDIS. Such standards could require that data be displayed exact- ly as provided by the relevant hydrographic office and that they be secure from corruption. Options for Incremental Improvements Accuracy and reliability are complicating factors in the effort to accord electronic charts the same legal status as paper charts. To help ensure the legal status of electronic charts systems in application, authorities could require that electronic charting systems meet international performance standards and rec- ommended practices (referred to as SARPS by the International Civil Aviation Organization [ICAO]~. Software could be designed to ensure that human opera- tors do not inadvertently screen out important navigation information, based on criteria that must be met for safe operation. To assure high reliability, electronic chart data bases could be provided by or under the direction of national hydrographic offices, which now produce paper charts. Norway and the United Kingdom have proposed developing inter- national data bases. The International Hydrographic Organization (IHO) has been reviewing these proposals as well as the possibility of developing regional elec- tronic chart data bases (Alexander and Black, 1993; Thomas W. Richards, NOAA, personal communication, April 30, 1993; Smith, 19931. Hydrographic data for U.S. waters could be improved by conducting timely modern surveys to provide complete bottom profiles for U.S. waters and to correct chart discrepan- cies. Ideally, ocean survey practices would have to be improved as well. This option would necessitate a commitment of substantially greater resources than now available for national hydrographic surveys.

NAVIGATING AND PILOTING TECHNOLOGY 229 The reliability of electronic charts could be enhanced further by the develop- ment of automated means for incorporating chart updates and notices to mari- ners concerning, for example, aids-to-navigation outages or buoys off station (Barber and Bass, 1992; Langran, 1992~. This technology has been available for several years but has not been applied to this purpose. If the technology is not applied, a vessel would be required to maintain updates to the paper chart, a substantial and perhaps unnecessary chore that, from the operator's perspective, would be human-resource intensive in an era of reduced crew numbers. Finally, the provision of accurate, up-to-the-minute weather and environ- mental information would enhance the safety of marine navigation through voy- age planning. Electronic data transmission systems could be established for broadcasting forecast data on tides, currents, and weather as well as real-time observations of environmental conditions. This would be a value-added feature that is not integral or essential to an electronic charting system. The service could be provided by the Department of Commerce through the National Weath- er Service and NOAA or perhaps by commercial vendors. Services could be publicly funded with or without cost recovery (such as user fees), or offered on a subscription basis. Certain information such as channel depth survey data could potentially be provided directly to users such as pilot associations by the survey- ing authority. For example, the U.S. Army Corps of Engineers sends daily hy- drographic channel survey data by facsimile to the Crescent River Port Pilots Association for miles 0 to 4 of the lower Mississippi River (Mark Delesdernier, Jr., Crescent River Port Pilots Association, personal communication, January 15, 1992~. Options for Long-term Development Voyage planning could be further enhanced through expanded deployment of real-time environmental information systems, such as NOAA's Physical Oceanographic Real-Time System (PORTS)(briefly described in Appendix G), to provide data for all major U.S. harbors. The PORTS system is an information acquisition and dissemination technology. The system integrates real-time cur- rent, water level, and wind measurements from multiple locations. Data dissem- ination is by telephone and includes modem dial-up (Appell et al., 1991; Bethem and Frey, 1991; NOS, 1990~. (See Weather and Environment Monitoring for related discussion later in this chapter.) Position Fixing The Traditional Approach Position fixing still relies heavily on traditional navigation techniques and technologies during a vessel's transit of pilotage waters. The process may or

230 MINDING THE HELM may not be difficult, depending on the availability of reference points and aids to navigation, visibility, and the frequency of maneuvering requirements. The pro- cess is much more difficult during periods of reduced visibility and darkness, when shoreline features, shore aids, and buoys may not be visible. (Buoys and other reference points may be obscured on radar by sea return or weather.) In any case, position fixing by conventional means leads to a determination of where the ship was when the data were collected, not where the vessel actually is. This is fine at sea but inadequate in pilotage waters, where the timing of maneuvering can be just as critical as in aviation with respect to ensuring a safe transit. There is unusually high interest among ships' officers and marine pilots in the emerging real-time position-fixing technologies. Using conventional techniques, a ship's position is determined by taking visual or radar bearings from fixed objects of known position or by obtaining latitude and longitude positions from electronic navigation instruments. At sea, ships' officers still sometimes use sextants to take sightings of the sun or stars, more to remain proficient in this traditional technique than to navigate. Taking sextant angles from fixed objects ashore is a traditional, highly precise position- fixing technique but is rarely used in piloting, although sextant angles may still be used occasionally to precisely position buoys. Position data, regardless of source, must be plotted on a navigation chart to determine the position of the ship with respect to the voyage plan and the land, channel, or other features shown on the chart. Pilots, regardless of proficiency in these practices, are ex- pected to determine positions based on expert knowledge of the local waterway using visual observations of local geography, aids to navigation, and radar pre- sentations. Watch officers usually plot positions on charts laid out on a plotting table installed in the pilot house. During this process, their attention is drawn away from other bridge team tasks. Plotting a fix can take 3 to 10 minutes or more, depending on mate proficiency; bridge layout; and operating conditions includ- ing visibility, familiarity with local geography and aids to navigation, and com- peting demands for the mate's services. The requirement for position fixes does not change when the vessel is under the direction and control of a pilot; this is one of the master's principal means of determining whether a pilot is performing effectively. However, difficult maneuvering conditions can quickly involve the mate or master in providing support to the pilot; for example, they may have to man the radar continuously in fog in a congested harbor. In such circumstances, there may not be adequate time to take and plot fixes in the normal manner. Further, in a narrow, winding channel, the taking of fixes is a full-time task requiring a dedicated navigation team, such as is typically found aboard Navy or Coast Guard vessels. For all practical purposes in such maneuvering conditions, the determination of the vessel's position is left almost entirely to the vessel's pilot, official or legal requirements for the master to maintain an up-to-date position plot notwithstanding. So, at the time that precise position data is most

NAVIGATING AND PILOTING TECHNOLOGY 231 needed, it is also often most difficult to obtain; maneuvering is thus based on the pilot's position estimate. These are the times when a pilot's expert knowledge and skills are essential and put to the test. However, the pilot is affected by the same operational and environmental factors as the master and mate, factors which may affect the accuracy of the pilot's position estimate. Under such operating conditions, the master's command responsibility to oversee pilot performance with respect to navigation safety is academic unless the master is also a qualified pilot on the route. Electronic navigation technologies, discussed below, hold considerable potential to overcome these shortcomings in traditional navigation practices. Mature technologies used for position fixing include paper charts; visual navigation aids such as lights, buoys, and ranges; enhanced radar navigation aids such as radar-reflecting buoys and racons; Loran C; and radio beacons used with radio direction finders (RDF). Two mature fixing technologies, RDF and Tran- sit, are expected to be phased out and replaced by GPS while Loran, Decca, and Omega are programmed to continue in service early into the next century.3 The High-Technology Approach Position fixing likely will be improved by several developing technologies that have yet to be completed or certified for navigation. These include GPS, the military satellite navigation system; DGPS, which is planned to provide civilian users with accuracy of 5 to 10 m in harbors and harbor approaches; GLONASS (Global Orbiting Navigation Satellite System), a Russian system similar to GPS; and electronic charting systems including ECDIS, which can display the ship's position, derived from DGPS or other position-fixing equipment, directly on an electronic chart.4 Of these, DGPS and electronic charting systems are most im- portant for pilotage in U.S. coastal and navigable waters. Pilots responding to the committee's inquiry were more enthusiastic about DGPS than about any other highly sophisticated technology (Ramaswamy and Grabowski, 1992~. Electronic charting systems would enable the master, pilot, and watch officer to visualize a vessel's position instantaneously relative to features displayed on the electronic chart. Available data can be taken from a sensor (such as DGPS) and placed into 3RDF fixes no longer meet modern requirements for navigation although RDF bearings remain useful for search and rescue purposes. The United States plans to terminate Transit in December 1996 (DOT and DOD, 1993). Omega is not expected to be terminated before the year 2005? and Loran C is to remain in use through 2015. 4The mariner must ensure that a ship's positioning systems and charts are based on the same horizontal datum and ellipsoid. Most U.S. nautical charts are based on the North American Datum of 1983 (NAD 83), which makes use of the ellipsoid specified in the Geodetic Reference System of 1980. The GPS uses the World Geodetic System 1984, which, for charting purposes, can be consid- ered equivalent to NAD 83 (Donald Florwick, personal communication, October 30, 1992). In other parts of the world, however, many different datums and ellipsoids are in use.

232 MINDING THE HELM Electronic charting system featuring an electronic chart and real-time positioning using differential GPS. (Trimble Navigation) context on an electronic chart display. Further, depending upon system features, the data that are displayed can be tailored or highlighted to meet specific needs, revealing, for example, safe operating depths. If an electronic charting system satisfied legal requirements for position fixing-the ECDIS concept it no long- er would be necessary to manually collect and process navigation data, except as may be necessary to confirm that electronic systems are functioning correctly. Although electronic charting systems and DGPS can be used separately, it is in their combined use that maximum benefits are obtained, because the detail on the electronic chart can be immediately related to position data. DGPS would feed ECDIS the most accurate positioning information available, and ECDIS would provide the real-time picture of the vessel's position, exploiting the posi- tion information for timely and effective maneuvering. A key barrier to achiev- ing these benefits is that international performance standards have yet to be approved for ECDIS by the IMO and IHO, although such standards have been drafted. Standards are expected to be approved and operational by 1995. But for now, ECDIS has no official legal status as a replacement for paper charts. Estab

NAVIGATING AND PILOTING TECHNOLOGY 233 fishing this status would require approval of international standards and port- state adoption of them. The mariners aboard the small number of commercial ships that carry electronic charting systems say they use them only as optional navigation aids. Other concerns about use of electronic charts include reliability and durability of electronic systems in a marine operating environment. Further, research on and development of these systems has yet to be completed (Alex- ander and Black, 1993~. In developing standards, it will be necessary to resolve the issue of what ECDIS is whether it is equivalent to, more than, or entirely different from a paper chart in terms of function (Hebden, 1990; Mukherjee, 1990b). Because it is impossible to predict all the future operational modes or uses for a technology, overly specific parameters could limit optimal usage and further development. Past debates over ECDIS specifications have centered on such details as which route-monitoring functions should be displayed, and how far in advance yet the technology had yet to be used. Questions of copyright and liability will need to be addressed (Dion, 1991; Ganjon, 1990; Gauci, 1990; Mackaay and de Kind- er, 1990; Mukherjee, 1990a; Obloy, 1990; Troop, 1990; Wiswall, 1990J. Most countries except the United States have copyrights to protect their investment in the cost of hydrographic surveys and in production of charts and data bases (Mukherjee, 1990a). (The Defense Mapping Agency EDMAJ is seeking legisla- tion to allow copyright of all or part of any mapping and charting products prepared by or for the agency EThomas W. Richards, NOAA, personal communi- cation, April 30, 19933.) There is also a safety concern that the data be used properly, although safety could be controlled through means other than copy- right, such as by regulations requiring use of "official" charts. The draft perfor- mance standards for ECDIS specify the use of charts from national hydrographic offices. Thus, it is likely that NOAA's Nautical Charting Division will be a major source of data. One possible model for handling ECDIS data is the system used by the Canadian Hydrographic Service (CHS) in managing the IHO Tidal Constituent Data Bank. The database contains astronomical information used to predict tides information that has commercial value. The CHS refers commercial re- quests to the country that originally provided the data in question (CHA, 1990~. Supporting Technologies and Resources An issue constraining the use of electronic charting systems and ECDIS is the availability of supporting technologies and resources, particularly the accura- cy of radionavigation signals (Box 6-2~. Eight to 20 m accuracy 2 dRMS (dis- tance/root mean square) is required for system planning and development of radionavigation aids for the safe navigation of ships and tows in harbors, harbor approaches, and U.S. coastal waters. It is important to recognize that GPS is a Department of Defense satellite-based system. For civilian users including com

234 MINDING THE HELM mercial marine applications, GPS provides horizontal accuracy to 100 m 2 dRMS, or approximately 95 percent of this accuracy (DOT and DOD, 19931. This limited accuracy is due to deliberate degradation of the system by DOD; normally, accuracy would be in range or 20 to 30 meters (Donald Florwick, NOAA, personal communication, October 30, 19923. To overcome this perfor- mance limitation and to minimize other systemic signal errors, GPS can be aug- mented by differential corrections to its range measurements based on the pre- cise location of a reference antenna, an approach referred to as differential GPS, or DGPS (Alsip et al., 1992; USCG, 19921. The present attainable 2 dRMS accuracy of DGPS is roughly 5 to 10 m (Alsip et al., 19923; accuracy may improve with the next generation of GPS receivers, as receiver errors (noise and multipath) are minimized (Cannon and Lachapelle, 1992~. The GPS is scheduled for full operation capability by mid-1995, while DGPS, a system originally developed by the Coast Guard to support its aids-to- navigation mission, is scheduled to be in place in 1996. A DGPS system is also being developed by the U.S. Army Corps of Engineers for use in the inland river system (Burgess and Frodge, 1992~. Full use of ECDIS depends on the availabil

1 1111 l~l/@i~iIl:14:1111.>i~113~31131~1~- of laid Life lis _ "-~=_~; 11 1~1111~111~lij#jilll~lllielll)sllll83llllellipi~lllllmuslllll~llc=dlll~#l~lllllif1d~l11111 1 llll~i~l~llli~llll~n#llll~llll~llllidll1 lll>~lll~llll~iblllll~I7111 23j ~ s s s s s s s s s s s s fly of COPS. The rapid development of technologies such as ECDIS may not be retarded by OPS maintenance problems but Ending rcsponsibiDtics far long- tc~ maintenance of the satcHitc system (or subsequent systems) bevy not been cst~lishod. Long-tc~ m~ntenancc of GPS and Ending far this need to be assured to underwrite the long-tc~ applicadon of n~vigadon cquipmcut relying on COPS. 3 ~r ^~f~ ~ If ~ ~/ ~f~~~ A/ i/~r [~- Could spur the rcscarcb and development needed to rcAnc the technology and cst~Usb as legal status. As noted carUcr, no nadona1 standards bevy been sat for commercial systems,5 but several intemational inidatives arc under way many recrcatioDal bowers use low-cost systems that provide real-time, precision navigation in- ~on. Use systems calculi, Die vowing defies ~ p=Ci~oD, Me position of arc vessel Em Lor=, GPS. DGPS, or over Tectonic systems Ed display it in mullion to ~ programmed voyage plan, electronic chap, or bow.

236 MINDING THE HELM to standardize specifications for data bases, display formats, and equipment per- formance. As emphasized earlier, performance-based standards would be prefer- able to equipment-based requirements. The liability issue is more complicated. Liability must be assigned for im- perfect data bases,6 improperly scanned or displayed hydrographic information, mistakes in transmission of chart corrections, and misuse of the technology. (A key legal problem will be how to prove cause and effect; that is, how to prove what appeared on the display at a given moment in the past, such as at the moment of a grounding. Draft performance standards for ECDIS require data to be stored for eight hours.) To encourage development of ECDIS in spite of the potential liability problems, the U.S. government could indemnify chart makers and manufacturers of electronic charting systems iincluding ECDIS) from any claim attributed to inaccuracy in an electronic data base provided by the gov- ernment. Indemnification of aeronautical chart makers has been legislatively required in only limited situations (P.L. 99-1901. Although the law is reported to have been interpreted to include electronic data bases provided by the govern- ment (Schultz, 1992), the legal status of this position is uncertain. In view of the potential benefit of electronic charting systems to improved navigation safety, it is desirable that the resolution of legal issues proceed in parallel with the further development and introduction of the technology. According to Daniele Dion, a maritime-law adviser to the Canadian govern- ment, the nature of liability could change in the transition from paper to electron- ic charts. Manufacturers could be liable if they made an inexact scan of the official hydrographic chart, or if the design (e.g., scale, symbols, graphics) of the chart were misleading, regardless of whether the contents were accurate (Dion, 19911. "Needless to say, the standard of a reasonable, prudent mariner will also be higher, and the criteria determining a vessel's seaworthiness will be higher" (Dion, 1991~. Although implementation of ECDIS will proceed regardless of legal issues because of the potential to significantly reduce operational risk, obtaining full operational benefits from this important technology could be constrained by cur- rent legal and regulatory requirements, which were written with traditional tech- nologies in mind, that affect navigation practices on the bridge. It would be helpful to review, and possibly modify or repeal, legal and regulatory requzre 6As noted earlier, survey total coverage is a problem with paper charts. Even so? few liability cases have been filed on the grounds of inaccuracy in nautical charts. The courts did set forth a number of principles in the 1982 case of Warwick Shipping Ltd. v. The Queen, ruling that the preparation and publication of a chart by a public authority does not imply that the authority has possession or control of the channel in question, as would be required to establish direct liability in Canada. The court also ruled that soundings "have no absolute value; they do not guarantee that indicated depth will remain or be maintained as shown, unless there is some indication to that effect on the chart" (Dion, 1991).

NAVIGATING AND PILOTING TECHNOLOGY 237 meets and expectations for bridge team operations and procedures that unneces- sarily constrain the application of high-technology navigation systems, to ensure consistency with ECDIS operations and to eliminate unnecessarily duplicative or counterproductive actions. Options for Incremental Improvement Several mature technologies could be altered or improved to support the use of new technologies. For example, even if ECDIS became the legal chart stan- dard, a paper chart might still be needed as a backup to cover the possibility of system failure or disruption. An alternative to existing paper charts may be suit- able. For example, a backup system might consist of periodic hard copies de- rived from the electronic chart data base aboard the vessel. (The IMO draft performance standards for ECDIS require a computer backup.) In addition, to meet pilots' expectations arising from the increased accuracy of onboard navigation systems, the accuracy of short-range aids to navigation may need to be improved. Any conflicts between real-time navigation input and charted buoy positions would become more obvious with real-time position- fixing capabilities. Some improvements in short-range aids already are being made. Most aids maintained by the Coast Guard have been converted to solar power (with back- up power sources). These modifications to short-range aids have extended ser- vice life, improved reliability, and reduced maintenance needs (Charles Mosher, USCG, personal communication, January 11, 19931. The Coast Guard is also switching from the old radar beacons mounted on buoys to frequency agile bea- cons and is planning to increase the number of beacons as well. The new bea- cons are expected to help mariners differentiate between buoys and ships on the radar display. In addition, high-power range lights have been developed to im- prove mariners' ability to see these aids in areas where there is significant back- ground lighting (such as near populated areas'; these advanced range lights have been installed in locations such as the Chesapeake Bay, where pilots report im- proved ability to distinguish navigation aids from background lights (Charles Mosher, USCG, personal communication, January 11, 19933. Finally, optics re- search and development is under way to increase the intensity of observed light emitted by rolling buoys. Other possible improvements would include more accurate and reliable placement of buoys and other fixed aids, wider distribution of ranges and high- intensity racons to support increased expectations for continued port operations in poor visibility, and development and installation of electronic ranges for use with either installed or portable navigation systems in poor visibility. The Coast Guard has already authorized the use of DGPS for positioning buoys. A concept for an interactive, portable electronic charting system, the portable communica- tions, navigation, and surveillance (PCNS) system, is described later in this chapter.

238 MINDING THE HELM It might be helpful to accelerate certification of GPS for two-dimensional navigation and to accelerate introduction of DGPS service in all major ports. In addition, planning and funding could be stepped up for development and distri- bution of electronic chart data bases, particularly for harbors and harbor ap- proaches. Likewise, the schedule for surveys and chart revisions could be accel- erated (by increased funding) to support the increased requirements for chart accuracy demanded by the DGPS/ECDIS display. The new surveys could be conducted using state-of-the-art technology to provide 100 percent bottom cov- erage in significant areas. And, to ensure that new technologies are used properly to reduce risk, it would be helpful to explore the human factors aspects of using electronic charts (such as boredom, fatigue, and human-machine interaction issues), including training needs. Options for Long-Term Development To accommodate the introduction of advanced technologies, long-term plans could be developed for enhancing and expanding the current system of short- range aids to navigation to meet expected needs. The Coast Guard, Army Corps of Engineers, local port authorities, and others involved in providing and main- taining the system could review existing policies and priorities and develop such plans, which could include early identification of funding needs. Finally, long-term plans for production of charts and other navigation prod- ucts and services could be reviewed by the National Ocean Survey (NOS), the DMAj the Corps of Engineers, the Coast Guard, and other government agencies to make sure the products offered are those required by users to support chang . . sing operations. Communications Bridge-to-bridge voice radio communications have become essential for co- ordinating vessel interactions. However, use of this medium for data exchange is inefficient, error-prone, and subject tointerference (NTSB, 1991b). Unautho- rized or inappropriate use of marine radio frequencies is reported at times to interfere with bridge-to-bridge communications, and to a lesser degree, with communications between vessels and VTS systems. Both VTS and bridge-to- bridge communications are often affected adversely by congestion on designated radio frequencies during times when bridge-to-bridge communications are most useful. Conditions when this occurs include adverse weather conditions, espe- cially fog, and severe traffic congestion or emergencies in the waterway that affect traffic flow. But the larger issue is that VTS (where available) relies heavi- ly on voice radio as the primary medium for data exchange. Problematic VTS communications practices also include selective screening of navigation infor- mation by shore-based personnel, transmission of important information at inop

NAVIGATING AND PILOTING TECHNOLOGY 239 fortune times (for example, while two vessels are engaged in communications to avoid or alleviate an emergency situation), and reliance on monitoring of all transmissions on VTS frequencies as a means of acquiring a comprehensive picture of current traffic. These factors compound communications problems by contributing to information saturation (see Chapter 5; Ahearn, 1992; Burnett, 1988; Ives et al., 1992; Young, 1992, 19943. Such effects can compromise rather than increase safety, a factor that merits legal consideration in the application of VTS (Barber and Dunning, 1989; Corbel, 1989; Gold, 1984, 19883. While at sea and approaching the coast, mariners can use satellite communi- cations (SATCOM) to communicate via satellite to conventional land telephone circuits (Fear, 1989; Mottley, 1992~. A number of improvements are being made to SATCOM, the use of which has been limited by cost. for example, the stan- dard antenna costs $30,000 and weighs 200 pounds. (Joseph D. Hersey, USCG, personal communication, January 12, 1993~. Per-call communications costs are also expensive and perhaps prohibitive: $10 per minute with a 3-minute mini mum. New, lightweight systems for both data and voice communications are being introduced. In addition, the Coast Guard reports that it has improved the overall communications system through enhanced connections to marine safety centers and an improved process for sending navigation warnings (Joseph D. Hersey, USCG, personal communication, January 12, 1993~. Mariners also may use cel- lular telephone to coordinate delivery of supplies. In a few cases, real-time tidal or other environmental information can be obtained through cellular access to reporting systems. During the 1988 port-wide tugboat strike in New York Har- bor, cellular phones aboard some vessels were used by masters as a means to privately schedule vessel departures with Vessel Traffic Service New York (Ives et al., 19921. However, these capabilities have been employed sparingly. Options for Incremental Improvements The overloading of frequencies is attributed in part to pleasure boats and in part to commercial fishing vessels. (The Bridge-to-Bridge Radiotelephone Act calls for use of Channel 13 by all vessels over 20 meters in length.) It might be useful to enforce aggressively regulations controlling the use of VHF radio chan- nels to remove unauthorized users. This may or may not be a practical option depending upon local circumstances; it might be impractical, for example, where there may be hundreds of small commercial or recreational vessels underway at one time. Communications could be improved in VTS operations to reduce the poten- tialfor human error and to increase the efficiency and electiveness of VTS-user interactions. (A related option for improving VTS surveillance capabilities is discussed in the next section.) Electronic data transmission capabilities are al- ready available for naval uses and have appeared in prototype form in commer

240 MINDING THE HELM cial marine operations. Such capabilities could be used to enhance the complete- ness and user-friendliness of VTS information provided to vessels for onboard interpretation and use. Concurrently, the VTS role could be shifted from inter- pretation of navigation information as a intermediary to high-level safety over- sight of the ever-changing traffic situation. While this concept is under examina- tion by the Coast Guard and a few marine pilot organizations for local VTS-like applications, it is not an element of present VTS operating procedures in the United States (Ives et al., 1992~. The Coast Guard reports that the concept is being more fully developed in the agency's VTS 2000 acquisition program, but it is not anticipated as an element of the next phase of Coast Guard VTS installa- tions (see Chapter 51. Another option would be to improve radio-circuit disci- pline, instituting standard language and procedures similar to those used in air tragic control communications. A technology advance that could be put to use for electronic data exchange is a portable interactive communications system, generically referred to as a PCNS (portable communication, navigation, and surveillance system). The PCNS system could be carried aboard by pilots to provide real-time, locally specific navigation information; to supplement standard shipboard navigation systems; or to provide an alternative if shipboard equipment is deficient. PCNS system architecture could be based, for example, on an experimental Swedish system used for navigation and automatic dependent surveillance (ADS) of aircraft (Nilsson, 19921. DGPS would be used as the position sensor for both navigation and ADS; in the latter case, position and velocity would be transmit- ted by a VHF data link. The PCNS system also would receive, process, and display information broadcast by the local collection site, which could be a VTS (Galyean, 1992), and by other nearby users. To be successful, the PCNS system would have to be lightweight, small enough to be carried and used easily, and sturdy enough to survive the pilot boarding process and the marine operating environment. All essential vessel and traffic data could be transmitted to and from a shore-based collection and retransmission station. The PCNS concept appears to be technologically feasible in the near term. Such a system is being developed for private operation in the Port of Tampa based on a 2-year study by the Greater Tampa Bay Advisory Council in which a number of marine pilots participated (John C. Timmel, Tampa Bay Vessel Infor- mation and Positioning System, personal communication, July 16, 1993~. An important communications advance is expected with the advent of digi- tal selective calling (DSC). Mariners will no longer need to monitor the VHF Channel 16 for establishing contact with other vessels and rescue centers; the implementation of DSC will provide the capability for automatic alerts (Joseph D. Hersey, USCG, personal communication, January 12, 1993~. DSC potentially could be applied to improve safety in pilotage waters, as discussed later in this chapter, and it is a feature employed in the Prince William Sound ADS system.

NAVIGATING AND PILOTING TECHNOLOGY ~ . . . .~ ~ ~ ~ ~ ~ ~ ~ ~ . ~ ~.~. ~ . . ~ . . ~ ~ ~ ~ ~ by. go. By. , ~ ~ ~ by. ~ by. , go. ~ Ail, ., ~ . ~ Portable DGPS receiver with electronic chart. (Raytheon Marine Company) 241 However, DSC may not have the capability needed for broad-based VTS or ADS applications. Options for Long-Term Development Marine pilots responding to the committee's inquiry suggested that voice radio frequencies be established for the exclusive use of professional navigators and pilots (Ramaswamy and Grabowski, 1992J. To alleviate channel saturation, additional VHF channels could be made available for commercial marine voice communications. If necessary, channel bandwidth could be narrowed consistent with currently available tuner technology. The Coast Guard has established an alternative frequency for a portion of the Mississippi River, a strategy that might be pursued elsewhere (Edward LaRue, USCG, personal communication, January 11, 1993~. The Coast Guard and the Federal Communications Commission (FCC) were soliciting comments through June 1993 on possible communications-relat- ed regulatory changes, including the splitting of the VHF band into smaller channels (Joseph D. Hersey, USCG, personal communication, January 13, 1993~.

242 MINDING THE HELM Collision Avoidance and Surveillance Collision avoidance and surveillance depend primarily on visual lookout, and the use of radar and Automatic Radar Plotting Aid (ARPA). In poor visibil- ity, radar and ARPA become even more essential. Mariners also listen for the sounds of other vessels, although this technique seldom provides a very accurate indication of distance or direction. Where available, VTS systems can provide ships with valuable information about vessel traffic and other hazards in harbors and approaches. Acquisition of essential information and effective safety oversight requires a combination of independent and dependent surveillance (Box 6-31. A variety of emerging technologies integrate collision avoidance and sur- veillance with other functions, such as position fixing and track keeping, or are intended to support one-person bridge operation. These integrated systems in- clude electronic charting system display of ARPA targets or radar images; use of radio frequency data links to provide ADS information about other vessels (e.g., identity, location, speed, course) on the ARPA or electronic charting system ARPA radar in use "aboard" a full mission ship-bridge simulator. (STAR Center Dania, Florida, American Maritime Officers)

NAVIGATING AND PILOTING TECHNOLOGY 243 displays; enhanced low-light video displays and night-vision goggles to assist in night lookout; and, to assist in poor visibility, amplified audio from directional microphone arrays to discriminate sounds and their relative directions. Options for Incremental Improvements Existing radar/ARPA technology is not entirely adequate. Pilots responding to the committee's correspondence said their most pressing technological need was for a highly improved radar system, particularly with improved target acqui- sition (including buoys) during squalls (Ramaswamy and Grabowski, 1992~. ARPA, meanwhile, does not have the resolution to solve problems involving close encounters, nor can it generate solutions quickly enough for transits requir- ing frequent maneuvering, such as in narrow, winding channels (Hosoda and Takagi, 1988; Zabrocky, 19923. Pilots also expressed concern about the delay in ARPA display of computerized information, as well as about the lack of stan- dardized consoles mentioned earlier. To take advantage of the accuracy of DGPS-derived course and speed-over- ground values and advances in radar and video processing, new ARPA functions and display capabilities could be developed. In addition, the international ARPA standards that require speed through the water measurements do not allow for more precise speed determinations using DGPS and could be reviewed and re- v~sed as necessary. Improved onboard plotting of targets is also possible, through use of automatic dependent surveillance shipborne equipment (ADSSE), dis- cussed later in this chapter. In addition, integrated navigation systems, also dis- cussed in more detail later in this chapter, could be developed that include dis- play of ARPA targets and radar video (along with functions included in the ECDIS display; Royal Institute of Navigation, 19931. Also, standardized outputs from ECDIS and other integrated systems could be used to support data trans- mission from ship to ship and to shore stations, such as a VTS. Finally, commer- cial and military systems for low-light video and directional sound discrimina- tion could be adapted and incorporated into these integrated systems. Another way to improve surveillance would be to revise procedures for VTS interactions with vessels, in order to reduce dependence on voice communica- tions and to take advantage of new technologies such as ADS. The use of ADS for surveillance could have significant operational advantages over radar. ADS offers greater accuracy and coverage than does radar in providing position, head- ing, and speed data, and it is also less vulnerable to environmental interference. The vessel tracks displayed at a vessel traffic center would be identified auto- matically and free of clutter. The periodic vessel broadcast of position, velocity, and intent also could be received and processed by nearby vessels as a comple- ment to ARPA. The ADS/VTS system mandated by the Coast Guard to satisfy Oil Pollution Act of 1990 (OPA 90) requirements for tanker operations in Prince William Sound will provide an opportunity to evaluate this concept, although in

244 ~ ......... l..'.......... I..... I.............. A.......... i''.''.... ~ .............. ............... ............ ..... ...... ,....... ...'..',..'..'. } . . 1 ' i.............. }........... MINDING THE HELM .. . . .... .... .. .. .. .... . .. . . ~ .......................... ,, , .,,,, ~,.~ ~ , ,.,.,+ X ........... . . . ..................... . ................... ~ ,x . 2 ' Y ~= ,,.w, - ~.,., ~.~.~ ~''"~.'"'""~'"2"''''"'' ' ' ''' ' it' ' ' it- ' ' ................................................................................................................................................................................................ ............................................. . s ¢) . ~X ~ s - ~ ~ ~ it' 'at'""" - ''' ......... . ~nK ......... -~ - s ~ m~ .............................................. ...................... .................................................................................................................................................................................... . ~,. ~., ~, ~ ......... 3 , ' , ' ,. ...... ', , , '''' ~''it ~ ' '"' ''I' . . .2 '.'_ "' ' " "''- "" " ' : "'.' , ' ,,.', ,,._ :'"' "''= ''it ~'.~' aft it .' '.,., ' -""'3 "' ""' ''" ' ' ''"' 3 ' ' " " ' ' ' " ' ' ' ' ' "' ' ' "' ' ' ' . ' ' ' " ' '.'.' '.' '.' ' ' ...... ' ' . '.' ~,:2:,.' ~,.,,'.,l~.,,.,.M,,,.,~.'"~""'~':"""~" i~_1~1 ................... . ~.. ............................................................... , ...'" ~'~'~ I''' ' ' ' ' ~ ~ {~ ~ ~9 ~ on v==ls^; - - - ad= ...~ ~_~howl~ge : . : ~ : ~: ~ = a low-traffic-density operating environment. Lessons from this application are expected to provide valuable insight for assessing the potential of ADS applica- tions for future use in marine traffic regulation if adequate performance infor- mation is collected during system implementation and operation. Options for Long-Term Development At present, DSC is the only practical data link available for ADS of vessels through VTS systems. It Is not bandwidth efficient (that is, the signal structure is not efficient) by contemporary standards, so it might not be adequate for ADS/ VTS in a busy port. Widespread implementation of ADS/VTS could overload VHF communication channels7 even beyond current levels of saturation. The Communications loading could be a major obstacle to ADS in ports such as New York or Puget Sound, where a high number of vessels (e.g. 40-60) may be tracked concurrently. DSC would require multiple VHF radio channels would to accommodate high-density vessel traffic operating environ- ments, necessitating allocation oi additional VHF frequencies for marine use. Such a requirement would appear to require regulatory changes.

NAVIGATING AND PILOTING TECHNOLOGY 245 latest study on DSC loading was completed in 1986 (Paul Ornstein, personal communication, December 16, 1992~. The same methodology is being applied to a study of ADS/VTS by the International Radio Consultative Committee, but, as of early 1993, that study had not been completed. For the future, the Coast Guard is looking at other means for data communications, such as satellites and highly efficient data transmission schemes for VHF. A more modern system could trans- mit many more information bits than can DSC in the same radio bandwidth. Channel loading is directly proportional to ADS requirements for vessel position updates; therefore, these requirements must be known to conduct an accurate loading analysis. The committee made a number of informal inquiries to industry and the Coast Guard to determine whether a definitive set of opera- tional requirements for ADS existed. No such guidelines were found. Opinions as to the optimal position-update interval for ADS ranged from 10 seconds to several minutes, depending in part on the vessel's situation and personal view- point. Thus, a comprehensive analysis may be needed of requirements for ADS

246 MINDING THE HELM Workstation-based VTS operator station. The latest generation systems integrate surveil- lance, tracking, electronic charts, radar overlays (or underlays), data management, record and playback, and expert systems incorporating local port rules, procedures, and operat- ing practices to provide a watchstander with a comprehensive representation of traffic activity and predictive capabilities. (Martin Marietta Ocean, Radar and Sensor Systems) data communications. The results could be used in a study of the potential for DSC channel loading related to widespread implementation of ADS/VTS. In addition, because DSC must be used as an international standard in the near term, the Coast Guard could accelerate its investigation of more-e~icient data communications systems. One possibility is the application of time division multiple access (TDMA), using GPS to define the time frames. An experimental TDMA system in Sweden is capable of providing 225 to 375 ADS reports every 6 to 10 seconds, for 225 to 375 vessels, in a VHF channel with a bandwidth of 25 klIz (Nilsson, 1992~. Steering and Track Keeping Establishment of a marine traffic regulation system analogous to that em- ployed in air traffic control would require, among other things, that vessels have the capability to precisely adhere to assigned paths (see Chapter 5~. Although precision navigation and adherence to planned tracks are technologically feasi- ble, they seldom are practiced in commercial marine operations. These approach- es are employed on a limited basis under very select operating conditions (Box

NAVIGATING AND PILOTING TECHNOLOGY 247 6-41. Most ships use a much more traditional approach. Steering is controlled by an autopilot at sea and a crew member in confined waters. As most ships do not have electronic charting systems or other real-time systems to display the ship's progress along a planned trackline, a course typically is ordered by the watch officer or pilot as a compass heading, which is maintained by the helmsman or quartermaster or set in an autopilot. The watch officer determines the heading by examining the past course plotted on the chart, noting any deviations from the intended track (set and drift), and predicting a heading that will provide a course that follows the voyage plan. At sea, where relatively large deviations can be tolerated, plotting may be done every half hour or so; these intervals must be smaller while approaching or in a harbor. In confined areas where rudder orders are often used for steering, the course usually is monitored in real time by visual observation of fixed aids to navigation, landmarks, or the radar display. In very confined waters, the master or pilot frequently controls the ship by ordering specific degrees of rudder movement rather than courses to steer. This method of steering provides the necessary control to offset or counteract the effects of physical forces but requires precise and reliable communications, con- siderable skill, and a very good understanding of the ship's handling characteris- tics and the hydraulic nature of the waterway. A pilot may also use a ship's anchor to enhance control over a vessel in certain confined maneuvering situa- tions (Armstrong, 1980; Hooyer, 1983; MacElrevey, 19881. A few ships are equipped with steering systems that are connected to and integrated with electronic charting systems, allowing the ship to automatically maintain a preset, minimum distance from the planned track line (a procedure known as cross-track error control). Ships that have an electronic charting sys- tem or radars displaying the voyage track line, but no interface to the autopilot, are steered in the traditional manner, but orders are based on visual observation of the cross-track error on the display. Mature technologies used in steering and track keeping include electrohy- draulic steering control, magnetic compass, gyroscopic compass (commonly re- ferred to as a gyrocompass, or simply, the "gyro"), rate-of-turn indicator, Dop- pler speed log, and autopilot. Some significant improvements to steering and track-keeping capabilities are expected in the near term; these include new sen- sors for speed over ground, heading, rate of turn, and pitch and roll. These advanced instruments, which will exploit the high accuracy of DGPS, are ex- pected to be significantly more accurate and reliable than are current indicators. Most new GPS receivers already display speed over ground. This information, when improved using DGPS corrections, is more accurate and reliable than speed through water as measured by the Doppler speed log. In addition, improved autopilots are being developed. The idea is to use sophisticated algorithms and advanced digital programming techniques such as neural networks to provide precise turning radii and maintain an accurate track.

246 ~s~ss~ssss~ 1111 1 III I ~ := I~III 1~ = ~ #I_I"~1~'I. HI llil'

NAVIGATING AND PILOTING TECHNOLOGY 249 A Small Business Innovative Research project sponsored by the Maritime Ad- ministration (MARAD) is evaluating the application of neural networks for an improved autopilot. Neural networks mimic the functions of the brain. They learn the attributes of the system in which they operate by observing and record- ing repetitive procedures and correlating the observations with programmed con- trol inputs and environmental variables. However, despite all this technological potential, most current autopilots use algorithms that do not model a ship's char- acteristics in shallow water very accurately. Other emerging technologies for steering and track keeping are related to integrated systems, discussed later in this chapter. Options for Incremental Improvements Existing steering and track-keeping technologies are relatively mature. In- cremental improvements in these functions depend on development of integrated systems and their components, discussed in this chapter. Options for Long-Term Development To enhance the near-shore utility of autopilots, improved algorithms could be developedfor predicting the turning rates and radii of ships in shallow water. Advanced autopilots have been shown to steer with much greater precision than does the typical helmsman. Computer-aided steering8 has been demonstrated through passages for which hand steering is not suitable (Gylden, 1987b, 1989, 1990; Herberger et al., 1991; Wallenius Lines, 19911. However, OPA 90 now requires hand steering in certain pilotage waters, as use of an autopilot may have been a factor in the Exxon Valdez grounding (Davidson, 1990; NTSB, 19901. Hand steering can be very effective and in some cases is the preferred method of steering, depending upon the proficiency of the helmsman and the circumstances of use (Gylden, 1987a,b). But, many pilots contacted during this study reported that helmsman skills have deteriorated. To some extent, this is the result of increased use of automatic steering systems and the more limited hand-steering opportunities (Gylden, 1987b). To take advantage of technical advances in steer- ing systems, regulations could be established, or the existing U.S. law amended, to allow the use of high-performance autopilots in pilotage waters and under certain operating conditions if superior steering can be demonstrated. Track keeping also could be improved by use of ECDIS, which can provide real-time position fixing more accurately and consistently than can plots on a 8These systems are actually a combination of ECDIS and a piloting expert system. The ferries are manned by permanent ship's officers, qualified to pilot on these routes, who have the expert knowl- edge necessary to judge the accuracy of computer-generated solutions and are in a position to over- ride these solutions if necessary.

250 MINDING THE HELM paper chart. But current regulations do not allow for the independent use of a system such as ECDIS. To facilitate the effective use of ECDIS, regulations could be issued to establish ECDIS and an electronic chart data base as equiva- lent to manual plotting, provided that suitable performance and operational objectives and standards are also developed and observed. Decision-Making Aids Integrated navigation systems have potential to enhance the immediacy and precision of information available on the bridge and, by consolidating displays, reduce the work load on the crew. Integrated systems are expected to reduce both accident risk and work load substantially, thereby supporting shipping com- panies in their efforts to reduce crew numbers and costs. Piloting expert systems can enhance safety further by reducing information overload and promoting time- ly and accurate decision making (Box 6-5~. Integrated systems have evolved as a result of digital controls and instru- ments and the increased capabilities of low-priced microcomputers. Most new marine controls and instruments are designed to accept inputs and outputs meet- ing a common standard, so they can be integrated easily and can communicate with microcomputers. These computers are capable of running very powerful programs that can handle, quickly and reliably, many navigation and maneuver- ing tasks, as well as engineering and cargo/ballast monitoring and control. Current integrated technologies have been applied to four types of systems: ADS; PCNS; integrated bridge systems (IBS)(Alexander and Spalding, 1993; Hederstrom and Gylden, 1992; Marine Log, 1993~; and integrated ship control systems (ISCS), which, in effect, integrate control of all other ship's systems with an IBS (Kasai et al., 1992; Kristiansen et al., 1989~. The consolidation of bridge displays is a significant benefit. (The task per- formance benefits are obvious if the IBS is compared with the traditional bridge layout described in Appendix G.) For the first time, the mariner is able to see and understand quickly the relationship of the ship to the environment. The three basic elements of the system are the digital nautical- chart, DGPS positioning, and radar overlay. These provide the mariner with position relative to the sur- rounding land, hazards to navigation, aids to navigation, and other vessels. Options for Incremental Improve7nents Bridge team management and decision making could be improved through accelerated development and use of integrated navigation systems. However, as technology becomes increasingly integrated, the issue of standardization becomes more important. Incompatibility of technologies will inhibit their integration. Most marine controls and instruments are designed to accept inputs and outputs meeting interface standards set by the National Electronics Manufacturing Asso

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Integrated bridge system aboard the Regal Princess. (Sperry Marine, Inc.) MINDING THE HELM ~ :.:: : ,,:,:.: $ ' '' .':~$.$.:. . ~ ~ ~ . ~ it. .............. 1 elation and promulgated as "NEMA 0183." It might be useful to develop more complete standards for NEMA 0183 in order to facilitate linkages among a greater number of shipboard systems. In addition, NEMA 0183 or a similar standard could be usedfor interfacing bridge equipment' and a standard similar to NEMA 0183 could be developedfor interfacing engineering and cargo/ballast systems with IBS. In addition, international standards regarding standardization of the re- quired alarms, displays, and controls to be located on the bridge of vessels equipped with ISCS could be developed for use by classification societies. Rules also could be developedfor thefi~nctional layout and design of bridges of ISCS vessels, to ensure the crew's access, from a single control station, to all required controls and information, including visual and audible lookout posts. Taking a broader perspective, traditional maritime operating practices may have to change if the full benefits of integrated technologies are to be realized. Many laws and regulations going back to the 1800s those dealing with watch- standing, manning, titles, and so on preclude the most effective use of integrat- ed technologies. An example is the requirement for a 12-channel GPS in an ADS system, discussed later in this chapter. To remedy that problem, ADS could be redefined to yield a performance-based minimum specification, which might pro- vide for equal or better performance than the current system at lower cost, while also allowing for improvements. Appropriate DGPS receiver standards to be used as reference for planning and development of new radionavigation systems are expected to be completed by the Radio Technical Commission for Maritime Services (RTCM) by summer 1994.

NAVIGATING AND PILOTING TECHNOLOGY 253 Meanwhile, because ADS technology is so costly, up to $50,000 per instal- lation for a large ship, its potential value in increasing efficiency in shipping and reducing risk has not yet been demonstrated. This limitation impedes voluntary user acceptance. Research and development could be conducted in an effort to simplify the ADS system and possibly yield a more economical package that wouldfind greater acceptance and quicker deployment in the internationalileet. If DGPS becomes mandatory for navigation, then ADS will become more attrac- tive to users. Most vessels would have to be equipped with ADSSE for ADS to become a primary means of surveillance. However, it may still be necessary to use radar to provide more comprehensive surveillance of other vessels, including fishing and recreational vessels, that would not be equipped for ADS but could affect the transits of commercial ships and tugs with tows. ADSSE, by displaying DGPS-based ADS data on the ship's bridge, could provide a very useful complement to ARPA. Vessel tracks based on DGPS are more accurate and more reliable than are radar tracks, because DGPS is inher- ently more accurate than radar and is not degraded by clutter or weather effects. Further, the accuracy of DGPS is enhanced when the system is used to gauge the distance between vessels. This is due to the cancellation of any common errors in the differential corrections. One concept for the application of ADS as a complement to ARPA involves a vessel receiving many ADS broadcasts from other vessels (by monitoring the ADS communications channel) but tracking and displaying only those targets within a selected range. Used in that manner, ADS shipborne equipment could reduce substantially the uncertainty and communica- tions workload now facing the mariner in determining the intentions of approach- ing or passing ships. If integrated with ARPA or used as input to an integrated navigation system, ADS shipborne equipment could provide faster and more accurate solutions for collision avoidance than are available now. As a near-term substitute for ADS and ECDIS, a PCNS system could be developed. The system could provide a means of coping with vessels that do not meet U.S. safety requirements concerning DGPS and ADS capabilities. The PCNS could offer no benefits until the Coast Guard DGPS network becomes operational. Although it may be possible to use electronic signals from privately operated radio-determination systems, under federal law and regulation only the federal government may operate most radionavigation systems for use in naviga- tion. Although federal regulations permit the Coast Guard to authorize establish- ment and operation of private aids to navigation, "with the exception of radar beacons (racons) and shore based radar stations, operation of electronic aids to navigation as private aids will not be authorized" (33 CFR 66.01-11. The light- weight, compact PCNS would be earned aboard by the pilot,9 perhaps in some 9The concept of the pilot bringing portable safety equipment on board is nest new. Some 30 years ago, VHF radios were brought on board by pilots, and the ship owners were charged for this service. Pilots continue to carry personal VHF radios as a standard practice.

254 MINDING THE HELM type of backpack. The system could be purchased by pilot associations and its use underwritten through a pilotage charge. The PCNS prototypes could be de- veloped for use in pilotage areas where equipment funding and Coast Guard research and development assistance were available. Apart from supplementing whatever navigation technology may be avail- able on older ships, the PCNS system could ensure that pilots have a familiar system to work with. As noted earlier, pilots are confronted with a bewildering array of shipboard technologies and permutations of equipment configurations. Further, new equipment does not necessarily eliminate the need for or use of the old. As the traditional maritime countries adopt new technology, the ships being replaced, rather than being scrapped, usually are sold to other (often smaller and foreign) operators.l° Meanwhile, the new ships compete, creating a continuous need for new cost-saving technology, and the world fleet is divided into an increasing number of technological tiers. Because of the lack of standardization, the demands on pilots would not be relieved even if all ships were equipped only with advanced technologies. Possible approaches to alleviating this problem in- clude enhanced pilot training, development of operational guidelines or stan- dards for equipment use, pilot-ca~ried navigation equipment, and provision of a pilot specially trained in navigation technology to provide and ensure adequate support for the lead pilot. Piloting expert systems, meanwhile, show promise for providing the reduc- tions in work load, information overload, and risk that would facilitate accep- tance of ISCS. As a component of an IBS, a piloting expert system could en- hance safety by providing a double check on pilot actions or sounding danger alerts. Preliminary assessment of such piloting expert systems through ship- bridge simulation suggests that bridge-team performance, particularly decision making, can be significantly improved (Grabowski, 19893. This may be the best use of expert systems. Stand-alone systems force human users to integrate a variety of disparate information available on the bridge, thus defeating the pur- pose of a decision aid designed to relieve information overload. Because expert systems are likely to be concentrated on ships with advanced bridge designs, continued research and development in expert systems could emphasize decision support for IBS and ISCS operations. In any case, use of piloting expert systems on old ships would require a retrofit with real-time local- area networks, because such ships lack the, necessary computing and communi- cations infrastructure.ll In addition, expert systems could be developed specifi 1OThis means that the increased supply of new ships is not matched by a corresponding decrease in the supply of old ships. The sheer number of ships poses increased operational and environmental risks, not to mention additional risk if operational systems are not adequately maintained. 1lIt is likely to be easier to introduce advanced technologies aboard new rather than existing vessels. Installing new technology on older vessels may prove too difficult or expensive depending

NAVIGATING AND PILOTING TECHNOLOGY 255 cally for piloting complex and heavily traveled waterways, where there is an immediate needfor reduction of operational risk. Knowledge bases for each port could be developed and tested as well. Finally, continued development of expert systems couldfocus on improving compatibility and integration with PCNS, IBS, or ISCS computer operating systems. Given adequate additional research and development, expert systems could fill gaps in integrated systems. The use of expert systems raises an issue of great importance to pilots- whether a human expert would be needed at all on a ship so equipped. But there is no guarantee that an expert system will perform or be used effectively. Fur- thermore, an expert system may not have all the local information necessary for safe navigation, and the system may not be linked to sensors capable of detecting vessel behavior relative to prevailing environmental conditions.l2 Therefore, a marine pilot would continue to serve the safety interests of the port state by providing a double check on the expert system as well as knowledge of and responses to local conditions. Manne pilots also could help validate the perfor- mance of expert systems; this assistance may be essential for system credibility in any case.l3 Eventually, the introduction of expert systems may alter the role of . . . marine pilots In some way. The effect of advanced technology on budge manning is also a concern. The introduction of new technology requires new operator skills that do not necessar- ily replace the more traditional skill requirements. Further, new potential for human error may be introduced. At times it may still be necessary for someone to steer the ship, such as when transiting a narrow canal or congested waterway where frequent maneu- venng is required to remain in the channel or to accommodate other traffic. If there is no longer a dedicated helmsman, hand steering requires some other on the bridge configuration of the vessel, its engineering systems, cost of modifications, and so forth. Thus, some advanced technologies may or may not be suitable for retrofit. Although an integrated bridge may not be feasible on an older ship, some of the principal benefits such as real-time position displays can be gained through the installation of ECDIS. 12Ideally, all published nautical information and other knowledge needed by the conning officer (or pilot) to maneuver the ship safely could be displayed and controlled at one station on the bridge. However, locally specific data and knowledge are required for which published data are not avail- able, or that require interpretation or response that are beyond the capabilities of existing sensors and computer-aided decision aids. For example, understanding of the hydrodynamic interactions between a vessel and channel bathymetry, and the collection of physical data needed to predict their effects, have been identified as research needs in using marine simulation for waterway design (NRC, 1 992a). The difficulties inherent in detecting hydrodynamic effects and maneuvering in response are com- pounded by the lack of real-time environmental data, the presence of other traffic, and the many other factors that affect vessel behavior (see Chapter 4). 13The threat represented by expert systems and other artificial-intelligence tools often can be mitigated by thoughtful and gradual introduction of the technology' the extension of benefits to affected workers (that is, crews and pilots), substantial theoretical and hands-on training, and phased introduction of the systems to oceangoing fleets.

256 MINDING THE HELM ship's officer or crewmember to undertake this task, in some cases abandoning other duties. If hand steering and response to voice commands from a pilot are not practiced regularly, the potential for human error and impaired task perfor- mance is increased. An IBS may be configured to support hand steering, but placing the mate (or master) in this role might increase task loading. Another view is that task loading might actually decrease if steering becomes an automat- ed function, relieving the watch officer or conning officer from having to moni- tor the helmsman's performance. However, the person steering the vessel would not be able to leave the steering position without a relief or engaging an autopi- lot. For example, it may be necessary to obtain a better view of an overtaking vessel from the bridge wing. There would also still be the potential for human error involving communications between a pilot and whomever is steering the vessel. Conceivably, the pilot could also take the helm, although how such ac- tion would affect the full range of piloting tasks is not clear. There is a significant difference between a "one-person bridge" and "one- person control." In the former, only one person would be on the bridge during operations. In the latter, direct control is exercised by one individual but others are on the bridge. One-person control is practiced aboard passenger ferries in the Baltic; typically, the master and an additional mate are on the bridge during transits of the most difficult sections of the pilot routes (Herberger et al., 1991~. Monitoring and cross-checking practiced as a matter of good seamanship in traditional ship bridge settings must be accomplished through technological means to offset the potential for "single-person error." Options for Long-Term Development To improve the accuracy of onboard or shoreside systems for surveillance and collision avoidance, one or more international radio frequencies could be dedicated to transmission of data among ships and between sliips and shore stations, and a more efficient standard data protocol (compared with today's standards, could be developed for transmitting data regarding a ship's identity, position, speed, and course. And to ensure compatibility of integrated surveil- lance systems among ships of various flags and the port facilities of different nations, IMO could develop an international standard for ADS. To determine the relative risk reductions provided by non-traditional bridge operations, the Coast Guard or MARAD could commission a quantitative, com- parative risk assessment of traditional, ECDIS, IBS, and ISCS operations. Cost- benefit analyses and risk assessments could be important tools for maximizing return on investment; at present, substantial sums are being spent on high-cost solutions to navigation problems that mitigate consequences (for example, dou- ble-hulled tank vessels to mitigate oil spills after an accident has occurred) rather than on before-the-fact preventative measures that may be more cost-effective or of greater overall benefit. To ensure that all technical issues are considered, the

NAVIGATING AND PILOTING TECHNOLOGY 257 comparative study would need to include participation by vessel operators and relevant equipment manufacturers. The IBS already has been identified as an important research topic (Box 6-6~. Determining the appropriate role of marine pilots with respect to the pilotage of ships with an IBS is also an important consideration that merits attention (Box 6-7~. Meanwhile, regulations could be developed to allow nontraditional bridge team organization for ships with IBS meeting acceptable standards. In particu- lar, these regulations could recognize the ability of the watch officer to operate the ship's controls without assistance from a separate helmsman and the capabil- ity of ECDIS to maintain a plot of the ship's position (Roeber, 1992~. Finally, manning laws and regulations could be reviewed and amended to

MINDING THE HELM facilitate training and licensing of a single class of watch officer. These officers would be responsible for all operating functions aboard ships equipped with ISCS meeting acceptable standards. At the same time, maritime academies could revise curricula to train for such a position. In devising such training programs, it is important to remember that new technology demands new skills but may not obviate the need for traditional skills such as those of the marine pilot, and,

NAVIGATING AND PILOTING TECHNOLOGY 259 furthermore, that technological advances may introduce new potential for human error. Automated systems may produce an economic benefit by providing for reductions in crew size, but safety benefits accrue only to the degree that proper use of advanced technology results in no increase in the probability of undesir- able events (Kristiansen et al., 1989~. Weather and Environment Monitoring Information about the weather and the operating environment is essential for safe navigation. Mariners need accurate forecasts to avoid potentially damaging storms and to determine tides and currents that will allow a vessel to enter port safely. To effectively maneuver a ship, they need real-time information about the speed and direction of the wind and currents, coupled with an understanding of how the forces exerted on the ship are expected to change within the confines of a harbor. The local pilot, after boarding, is usually the best source for port- specific information, but the ship also must have significant onboard capability. Mature technologies for monitoring and predicting environmental conditions in- clude the recording barometer; anemometer and wind-direction instruments; tide and current tables; and weather telefacsimile receivers, programmed to receive forecasts and weather maps. Several new technologies are being tested or introduced that show great promise for reducing the risks posed by the uncertainties of the marine environ- ment. These include electronic tide predictors (Mays, 1992~; the PORTS system noted earlier (briefly described in Appendix G), now installed in Tampa, Florida (Appell et al., 1991; Bethem and Frey, 1991; Frey, 19913; weather routing ser- vices, which provide forecasts as well as recommendations for changes in voy- age plans to avoid severe weather; and hull-stress monitoring systems. Options for Incremental Improvements The availability of ECDIS will provide an opportunity to apply new technol- ogy for real-time monitoring of sea conditions. At present, PORTS data are transmitted by radio on an hourly basis. Real-time radio transmission of PORTS data and modification of ECDIS could enable the use of real-time data for EC- DIS display of actual water levels and wind and current vectors. In addition, systems for monitoring hull stress could be enhanced by development of highly reliable hull stress-sensors and methods for mounting them that could withstand the marine environment. Options for Long-Tern Development The PORTS system could be extended to all major U.S. harbors, concentrat- ing first on those where the need for real-time tide, current, and weather data is determined, by consultation with the marine industry, to be the greatest. A1

260 MINDING THE [IELM though the PORTS system has been very well received by its marine users, NOAA reports that agency resources are not available for long-term operation, much less for expansion of the capability to other ports. The agency has suggest- ed that revenues collected from the marine transportation industry and main- tained in the Harbor Maintenance Trust Fund (in excess of funds needed for channel maintenance) might be an appropriate source of funding for continua- tion and expansion of the PORTS program. Docking Evolutions Docking large vessels is a time-consuming and potentially hazardous opera- tion. The velocity and position of the ship as it approaches the dock must be controlled carefully to prevent damage to the dock or the ship. This maneuvering requires skill and experience; control of the ship's engine, rudder, and bow thrust- er (if available) must be coordinated accurately with the forces provided by one or more tug boats to achieve proper velocities in an environment of wind and currents. Little research and development has been conducted in recent years related to docking technology, although two types of technologies have been introduced: dual-axis docking Doppler systems and constant tension winches. Constant ten- sion winches are very useful during docking evolutions. They are designed to maintain constant tension on the wire ropes used to winch or hold a ship along- side a pier. The tension can be set to avoid the parting of these ropes that would endanger linehandlers on the ship and the pier and that would complicate dock- ing. This feature also allows the ship to be warped along the pier to attain the desired position. Tests are being conducted with automated docking systems. Real-time pre- cision navigation systems also can be employed in such systems. For example, installation of DGPS antennas on both the bow and stern could be used to pre- cisely monitor both the forward and lateral movement of the vessel during dock- ing maneuvers. Options for Incremental Improvements Automated docking systems are a promising new technology. Ongoing re- search and development could be accelerated to allow early implementation of automated docking systems, which could be helpful in certain U.S. ports. Ade- quate control and positioning technology is available, but additional research and development is needed to produce autonomous systems. Such systems are under development in a number of countries as part of "intelligent ship" pro- grams. The most notable advances have been made by the Japanese, who in 1990 conducted an evaluation of their automatic berthing and unberthing system

NAVIGATING AND PILOTING TECHNOLOGY 261 aboard the experimental ship Shoji Maru.14 Experiments with the Japanese sys- tem showed that smooth and accurate transitions to and from berth were possi- ble, that the orders generated by the system mimicked those expected from an experienced captain and docking master, and that the approaching speed of the ship was reasonable and safe. Although autonomous systems have yet to be deployed, a number of experimental docking-assist systems are undergoing eval- uation aboard operating vessels. Winches require heavy maintenance because of the harsh environment of the weather decks on which they are located. It might be useful to develop more- reliable and less-maintenance-intensive winch-control systems to ensure their availability for use during docking evolutions. Options for Long-Term Development No specific options for long-term development were identified. TECHNOLOGICAL CHANGE How Marine Navigation Technology is Adopted Historically, advances in marine navigation technology have been driven largely by military needs and considerations (such as radar in World War II), and to some degree, by marine-related missions of federal agencies (e.g., the aids to navigation maintained by the Coast Guard). Now, however, certain advanced navigation equipment can be applied as an integral part of bridge design to gain an economic benefit. Advances in electronics and space technology permit auto- mation and integration of navigation tasks such as fixing and displaying the ship's position. Automation facilitates reduction in manning, a change in prac- tice pursued by the shipping industry to reduce operating costs; automation also can be applied to expedite the work of the remaining crew, a useful feature on complicated modern ships. The trend is for ships to become more automated overall (NRC, 1990a).l5 Change generally has evolved slowly in the marine industry, in part because most technology has not been developed or regulated centrally. However, eco- nomic competition has increased the pace of technological change. History shows 14The Japanese Intelligent Ship Project is a joint research program organized and managed by seven shipbuilding companies under the Shipbuilding Research Association of Japan. The ship is owned by Tokyo University of Mercantile Marine. 15Technology exists for remote and centralized monitoring and control of the engine room; water and fuel flows; and such functions as navigation, loading and unloading, distribution of ballast for stability, maintenance, inventory of parts and stores, and even administration (Ohmes and Robinson, 1987).

262 MINDING THE HELM that shipping companies adopt new technologies if their actual use substantially reduces operational risk and uncertainty (and thereby economic risk). The speed of adoption depends on availability and reliability of the technology, its proven value through demonstrated effective application, and its cost. Another factor affecting application is that use of advanced technologies involves a complex of changes related to design, performance, and reliability, some of which may in- creaserisks(Aranow, 1984;NRC, 1991b;Reason, 19923.0therimportantfac- tors affecting technology acceptance and application are impediments to innova- tion and application of technology embodied in laws, regulations, and legal precedents. Two examples of adopted technologies, albeit motivated by official man- dates, are bridge-to-bridge communications and radar. Marine pilots now con- sider VHF radio and radar fundamental to piloting practice and have been instru- mental in establishing their near-universal application. This is a legal as well as a practical choice. If a pilot fails to use available proven equipment and an acci- dent occurs, then a defense of prudent seamanship becomes vincible in disciplin- ary proceedings. This concern may be applicable to newer technologies if their use becomes "fundamental" to basic navigation practices. Marine Transportation Companies and Technological Change The key force driving the installation and use of navigation technology by marine transportation companies is economics, although the economic contribu- tion of safety improvements and public interests in safety may in some cases be strongly considered in decision making. If the economic benefits of a technology are not obvious-and they may not be then vessel owners are not inclined to buy it without an official mandate that provides incentives or requirements to do so. The economic influence in a highly competitive industry is so powerful that it could work against a safety scheme based on universal voluntary application of specific technologies. Increases in operating costs (including any associated with mandated technology) that affect financial well-being could lead to a shake- out in ship routing, fleet composition, or both. This result would determine whether there would be a net benefit in economics or safety. Nevertheless, a small but growing number of operating companies have made considerable in- vestments in high-technology integrated navigation systems, for example, to fa- cilitate uninterrupted passenger service or to reduce operational (and economic) risk in tanker or freight operations (Herberger et al., 1991~. Mariners and Technological Change Dependent as it is on evolving economic, safety, and legal pressures; tech- nology acceptance can be an arduous, piecemeal process. Mariners are often ambivalent about change, and they tend to cling to proven traditional methods

NAVIGATING AND PILOTING TECHNOLOGY 263 until convinced that a new technology works. As an illustration, testimony solic- ited from marine pilots indicates that their work remains more an art than a science. Some feel that "more sophisticated technologies do not contribute much, and may only serve to increase the load on the pilot" (Ramaswamy and Grabows- ki, 19921. Yet many pilots have become ardent advocates of technologies such as radar, and especially over the last several years the use of marine simulation for continuing professional development. Likewise, if emerging high-technology navigation systems can be demonstrated to be significantly helpful in their work, marine pilots are likely to become ardent supporters of universal use of such technologies. That is, they will unless operating companies attempt to substitute advanced technology for pilotage services, thereby reducing pilotage costs and threatening pilot livelihood. Although some marine pilots have promoted the use of advanced navigation technology, for example, the use of bridge-to-bridge radiotelephone (USCG, 1972), pilots in the past infrequently were brought in at the "proof of concept" stage of technology development, with the notable exceptions of computer-based marine simulation for channel design, and more recently, in developing some VTS systems (Maio et al., 1991; NRC, 1992aJ. Perhaps pilots were not called on more for the development of navigation technologies, because visual piloting is still relied on to a significant extent in confined waters. But public expectations for the safety of vessel operations are changing, and there are unmet needs for all-weather, precision positioning capabilities. However, marine pilot expert knowledge of shiphandling and confined water operations is a resource that could be better used in the research and development of advanced systems, to help ensure that these systems will achieve their full potential in reducing risk in pilotage waters. Further, marine pilots are in a unique position to assist in vali- dating newly introduced technologies and to provide leadership in their applica- tion (such as for pilot-operated VTS or VTS-like systems). What is occurring in marine transportation, then, is a convergence of old and new navigation practices. The traditional and trusted piloting methods, which rely heavily on visual observation (of varying acuity), use of radio and radar, and the application of expert local knowledge, are being weighed against high-tech- nology solutions that offer real-time information and support for precision navi- gation and decision making but that have yet to inspire confidence and trust. This quandary contrasts with the situation in aviation, where new systems are tested by central authorities, and U.S. industry routinely complies with the mandated schedule for installing and retrofitting the devices on all aircraft (Gold, 1990a). ICAO16 has broad powers to promulgate standards and practices for new 16The ICAO is more active and more adequately funded than the IMO, which is funded in accor- dance with the respective tonnages of flag states. The IMO funding scheme is a problem because over 20 percent of the world's tonnage is registered in Liberia and Panama; neither nation has contributed to IMO activities in recent years due to internal financial difficulties in each country (CHA, 1990).

264 MINDING THE HELM systems. The development and implementation process is said by some to unfold relatively quickly, although this depends on the point of comparison. What is more, considering the total capital and operating costs of aircraft, measures which enhance safety and performance were routinely considered as cost-effective (Gold, 1990a). This receptiveness appears to have changed somewhat as a result of less favorable economic conditions in the aviation industry. Nevertheless, the well-established strong organizational structure and institutional processes that facilitate the introduction of technology remain in place. The acceptance by U.S. airlines of the Microwave Landing System (NILS) provides a cogent example of more recent conditions. MLS was developed and shepherded through ICAO by the United States as the landing system for the next century. However, with the advent of satellite navigation, the airlines have convinced the Federal Aviation Administration to establish a vigorous develop- ment program to determine the feasibility of DGPS application to precision ap- proaches, including Category III approaches (zero ceiling limitation). This user initiative is based on economic benefits, where airlines believe that the flexibili- ty of satellite navigation, with respect to coverage at all airports worldwide, user preferred routes, single system for all phases of navigation, and application to automatic dependent surveillance, will lead to substantial costs savings in their operations (RTCA, 1992~. Pitfalls of the Application Process: Some Examples The introduction of new navigation technologies has been met more by operator reluctance to give up traditional systems than by forward-looking en- thusiasm. The absence of wholehearted support has created a number of prob- lems concerning advanced technologies, including lack of standardized equip- ment, a shortage of validation methodologies, regulatory standards that constrain either optimal usage of technology or its further development (or both), require- ments for specialized training, and considerable reliance on traditional practices even when using advanced systems. Following are specific examples. Multiple Equipment Configurations and Regulatory Restrictions Two problems multiple configurations and regulatory restrictions are il- lustrated by ARPA. Marine pilots responding to a committee inquiry complained about the lack of standardized ARPA consoles, a frequent cause of pilot difficul- ty in using this equipment effectively (Ramaswamy and Grabowski, 19921. Such difficulty poses a safety risk if bridge team support to the pilot in making effec- tive use of ARPA is inadequate, perhaps even canceling out the collision-avoid- ance safety benefit ARPA is supposed to provide (Ramaswamy and Grabowski, 1992; Zabrocky, 1992~. Further, ARPA's capabilities are specified-and limit ed by regulations (33 CFR 164.383. ARPA's plane of reference must be the

NAVIGATING AND PILOTING TECHNOLOGY 265 water plane; that is, speed data should be obtained through the water signal. But water-speed instruments-once the only technologies available for determining speed are neither very accurate nor very reliable. Today, navigation equipment using DGPS signals can measure speed very accurately over ground. This data cannot be used with ARPA, however, because regulations do not provide for measurements by means other than water speed instruments. The result is that mariners, frequently unable to obtain an adequate water signal, often enter speed information manually, sometimes forgetting to change it later. Resulting ARPA solutions are degraded in relation to the error introduced, increasing operational risk. Regulations addressing technology application can either foster or impede research and development, depending on how they are written. For example, a 12-channel GPS receiver is required by the Coast Guard for the ADS/VTS sys- tem for tank vessels over 20,000 deadweight tons in Prince William Sound (33 CFR 161.376~. As written, the regulation does not provide adaptive flexibility or include provisions or incentives to motivate further improvements in positioning accuracy or system integrity. But if the wording were changed to specify a min- imum integrity comparable with that provided by the 12-channel GPS receiver, the regulation still would result In the near-term adoption of this equipment while also providing latitude for subsequent technological innovation. Pe jormance Objectives and Assessments Another concern is that construction and performance standards are not available to guide the introduction of high-technology systems or to minimize the unconstrained proliferation of different configurations and features. Advanced technologies are becoming more reliant on software and therefore can be modi- fied very rapidly much more rapidly than can traditional hardware-based tech- nologies-for the purposes of correcting deficiencies and improving capabilities (Buxton and Hornsby, 19921. However, the range of possible permutations and the speed at which they can be made and introduced has the potential to exacer- bate the difficulty that mariners, especially pilots, have in building and maintain- ing familiarity with high-technology navigation systems. These difficulties are compounded, because only a few standardized methods have been developed for validating software short of extensive field trials. Validation is a current research topic in the software engineering community and vessel classification societies (Buxton and Hornsby, 1992; MacIennan and Shaw, 1992; Singpurwalla and Wil- son, 19931. Such tests are the principal method for determining logic or pro- gramming flaws in software and evaluating actual system performance relative to designed capabilities. For example, before new or updated personal computer software is introduced for sale, in addition to bench tests, special field trials, referred to as "beta" tests, are conducted by individuals selected to challenge

266 MINDING THE HELM software capabilities and performance. Many, but not necessarily all, "bugs" in the software are identified for subsequent correction. Generally, software can be tested without creating any physical danger. However, this is not the case for field testing either software or hardware in marine systems. It is difficult if not impossible to stress a technology sufficiently to see if it works, in either a port-and-waterways operating environment or river system, without exposing the vessel serving as the testbed to some physical dangers. These dangers become more pronounced as the pilotage waters or traf- fic situation become more challenging. For most potential applications, it does not appear economically feasible to employ large vessels in commercial service as dedicated testbeds, although some limited trials may be feasible. Further, operational risk in conducting such tests might be significant. Although small, maneuverable vessels could be employed as testbed platforms for beta-like tests, even this is costly, not entirely without risks, and it appears to the committee, not frequently done. Whether or how well the results of such testing would transfer to larger platforms of far different design, outfitting, and manning has not been ascertained. Simulation technology has been used in a few cases to evaluate a new tech- nology (Grabowski and Wallace, 1993; Schuffel et al., 1989) or to test technolo- gy utilization (Akerstrom-Hoffman et al., 1993; Alexander and Klingler, 1992; Gonin et al., 1993; Smith, 19931. Simulation offers a controlled environment absent of physical dangers to the participants, and the ability to test the technol- ogy under operating conditions too dangerous for field tests. Although far less costly than field tests for the same level of empirical observation, the cost and time-intensive nature of simulation, and the need to install and effectively inte- grate the technology into the simulation, have impeded widespread adoption of this technology for this purpose. Another testing approach is to combine use of marine simulation and afloat testbeds. This is the approach employed in the U.S. ECDIS Testbed Project, a multifaceted government-industry demonstration, test, and evaluation project. The project is supporting the development of international performance stan- dards for ECDIS by the IMO. The U.S. researchers are testing the capability and limitations of prototype ECDIS systems; evaluating the adequacy of proposed international ECDIS design and performance standards; and examining the in- corporation of the human-machine interface into ECDIS design, operation, and performance (Alexander and Black, 1993; Alexander and Klingler, 1992; Gonin, 1993; Marine Log, 19921. Controlled experiments and tests that could not be readily performed at sea were conducted using marine simulation (Akerstrom- Hoffman et al., 1993; Alexander and Klingler, 1992; Gonin et al., 1993; Smith, 1993~. Afloat tests have employed a ferry boat, a 180-foot Coast Guard buoy tender as the testbed, and a maritime academy training vessel. Although these vessels did not exactly represent large commercial ships in terms of bridge con- figurations, maneuvering characteristics, and manning levels, the tests that were

NAVIGATING AND PILOTING TECHNOLOGY 267 conducted yielded valuable insight for the ECDIS testbed project (Gonin, 1993; Gonin and Crowell, 19923. Ultimately, it appears that a technology must be field-tested aboard the pre- cise class or type of vessel for which application is intended to determine effec- tiveness for that type of platform in the range of operating conditions that will be experienced. Field trials also appear to be needed for each individual installation, because of differences among vessels, even those of the same type or class (see Chapter 41. In select cases, it may be possible to obtain a broad base of experi- ence with a new technology by applying it on regular routes, with regular bridge- team personnel, over a wide range of operating conditions and for an extended period. This approach was used to evaluate and build trust and confidence in integrated bridge systems aboard large passenger ferries in the Baltic (Herberger et al., 1991.) However, little if any formal performance monitoring of applied technologies seems to be the norm. (Previous NRC assessments have consistent- ly identified a need for more systematic assessment of safety needs and perfor- mance of safety measures and safety data to support such assessments tNRC, 1990a, 1991a].) There appears to the committee to be a general reliance on informal evaluation by shipboard personnel; their operational insight is essential, but few mariners are prepared to evaluate technical performance scientifically, especially of software, that requires a programmer's critique. As a general practice, a new technical system is usually installed aboard a vessel, and experience is gained with it through actual operations. A danger in this approach is that mariners might become prematurely confident in the new technology through its continued use at sea rather than through experience with it in pilotage waters. Yet, it would be imprudent to rely solely on a new technol- ogy for navigation in pilotage waters without establishing a solid basis for trust- ing it. Therefore, despite the apparent potential of emerging technology to im- prove navigation, a conservative approach to operational acceptance is justified, especially with regard to the software-based technology. At the same time, the desirability of reducing operational, economic, and environmental risk argue for prudent acceleration of technology introduction, validation, and acceptance. Performance Objectives vs. Equipment Mandates Considering the pitfalls and uncertainties that may be encountered in intro- ducing new technology, it may be advisable to develop baseline standards that emphasize performance objectives rather than mandating specific equipment. Performance-based standards leave room for flexibility in exceeding the require- ments or meeting them in new ways, thereby allowing users to respond to dy- namic changes in needs and to employ technological advances as they become available. This approach has taken hold in civil aviation, where the trend is toward specifying required navigation performance rather than the carriage of designated equipment (RTCA, 1992~. The user thus may choose the navigation

268 MINDING THE HELM configuration that satisfies both legal requirements and individual preferences. Of course, this advantage could be lost if, to achieve a specified level of perfor- mance, a navigator had no option but to use one particular type of equipment. Ensuring Pilot and Watch Officer Proficiency Among the new problems posed by advanced technologies are the subtle difficulties involved in their practical use (Perrow, 1984~. The introduction of radar into the fleets provides a useful example. A number of marine casualties suggested that the watch officer or pilot sometimes became so engaged in oper- ating the radar that awareness of the larger navigational picture was lost, result- ing in decisions that contributed to or caused collisions. Marine simulation re- search determined that watch officers sometimes became more absorbed with a problem when using radar than with visual sighting or when computer-aided decision aids were available (Aranow, 19841. This phenomenon became known as "radar-assisted collisions" (Hebden, 1990; NTSB, 1972; Wenk, 19861. The term is also used to refer to collisions associated with pushing the limits of safe operations by relying on radar during periods of reduced visibility. Radar en- ables maneuvers or speeds that would not normally be attempted if radar were not available, but these actions may not be prudent. Similar problems are possible with new navigation technologies such as integrated radar and electronic charting systems if they are not used carefully. What is more, if masters, other members of bridge teams, and marine pilots have to become familiar with new systems through on-thejob experience, they may find it difficult, if not impossible, to learn effectively without at the same time compromising the integrity of piloting or watchkeeping. To minimize such a possibility, training requirements for new technologies would need to be deter- mined and, insofar as is practical, training provided prior to using the technolo- gy. Alternatively, special provisions could be made to ensure that proficiency in the use of the new technology was established without compromising safety and performance. This level of training is employed routinely in commercial avia- tion. Technology-Induced Changes to Pilotage The time-honored methods of piloting, recruitment, and on-thejob profes- sional development may be challenged by inexorable technological changes. With the emergence of sophisticated technologies and new bridge configura- tions, marine pilots find themselves and their profession under increasing pres- sure to update their practices to make use of these new capabilities. In the past, marine pilots adapted to such changes as new technology as it entered the commercial fleet and appeared in their service area. This was an adequate approach, because the slow pace of change provided sufficient time for

NA VIGATING AND PILOTING TECHNOLOGY 269 pilots to become familiar with new systems. Likewise, traditional pilotage sys- tems and pilot development programs were adequate to meet professional-devel- opment needs. However, the existing systems and programs are not structured to develop the needed technical skills in a rapidly changing operating environment (see Chapters 1 through 31. Associated training issues are discussed in Chapter 7 and Appendix F. Chances are that marine pilots will find it necessary to adapt to changing technologies to satisfy the professional expectations of operating companies, masters, and public authorities concerned with operational and environmental safety. How quickly this need will develop is not certain; given the swiftness of technological advances and the lack of universal, continuing professional devel- opment programs, it could be soon.

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Large ships transporting hazardous cargoes, notorious marine accidents, and damage to marine ecosystems from tanker spills have heightened public concern for the safe navigation of ships.

This new volume offers a complete, highly readable assessment of marine navigation and piloting. It addresses the application of new technology to reduce the probability of accidents, controversies over the effectiveness of waterways management and marine pilotage, and navigational decisionmaking. The book also explores the way pilots of ships and tugs are trained, licensed, and held accountable.

Minding the Helm approaches navigational safety from the perspectives of risk assessment and the integration of human, technological, and organizational systems. Air and marine traffic regulation methods are compared, including the use of vessel traffic services.

With a store of current information and examples, this document will be indispensable to federal and state pilotage and licensing authorities and marine traffic regulators, the Coast Guard, pilot associations, and the shipping and towing industries. It will also interest individuals involved in waterway design, marine education, and the marine environment.

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