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3Navigational Safety 7 3NAVIGATIONAL SAFETY 7 CHAPTER 27. NAVIGATION PROCESSES ...................................................................................................433 CHAPTER 28. EMERGENCY NAVIGATION ................................................................................................443 CHAPTER 29. NAVIGATION REGULATIONS .............................................................................................453 CHAPTER 30. MARITIME SAFETY SYSTEMS ............................................................................................463 CHAPTER 31. REPORTING..............................................................................................................................479 CHAPTER 27 NAVIGATION PROCESSES INTRODUCTION 2700. Understanding the Process of Navigation failure, which must be backed up with another source to ensure the safety of the vessel. Navigation is comprised of a number of different pro- It is also the navigator’s responsibility to ensure that cesses. Some are done in a set order, some randomly, some they and all members of their team are properly trained and almost constantly, others only infrequently. It is in choosing ready in all respects for their duties, and that they are using these processes that an individual navigator’s experi- familiar with the operation of all gear and systems for ence and judgment are most crucial. Compounding this which they are responsible. The navigator must also ensure subject’s difficulty is the fact that there are no set rules re- that all digital and/or hardcopy charts and publications are garding the optimum employment of navigational systems updated with information from the Notice to Mariners, and and techniques. Optimum use of navigational systems var- that all essential navigational gear is in operating condition. ies as a function of the type of vessel, the quality of the Navigating a vessel is a dynamic process. Schedules, navigational equipment on board, and the experience and missions, and weather often change. Planning a voyage is a skill of the navigator and all the team members. process that begins well before the ship gets underway. Ex- For the watch officer, ensuring the ship’s safety always takes priority over completing operational commitments ecuting that plan does not end until the ship ties up at the and carrying out the ship’s routine. Navigation is their pier or drops anchor at its final destination. It is rarely pos- primary responsibility. Any ambiguity about the position of sible to over plan a voyage, but it is a more serious error to the vessel which constitutes a danger must be resolved under plan it. Carefully planning a route, preparing required immediately. The best policy is to prevent ambiguity by charts and publications, and using various methods to mon- using all the tools available and continually checking itor the ship’s position as the trip proceeds are fundamental different sources of position information to see that they to safe navigation and are the marks of a professional agree. This includes the routine use of several different navigator. navigational techniques, both as operational checks and to This chapter will examine navigational processes, the maintain skills which might be needed in an emergency. means by which a navigator manages all of the resources at Any single navigational system constitutes a single point of their command to ensure a safe and efficient voyage. BRIDGE RESOURCE MANAGEMENT 2701. The Navigator as Manager voyage management software package and an ECDIS or ECS system that may replace the ship’s paper charts. Many The development of computers and navigational systems can be integrated with the charting systems technologies driven by them has led to an evolution, some including AIS, radar overlay, dual interswitched X- and S- might say revolution, in the role of the navigator. band ARPA radars, track or heading control, digital flux Increasingly, the navigator is the manager of a combination gate and ring laser gyrocompasses, GPS/DGPS positioning of systems of varying complexity, which are used to direct systems, numerous environmental sensors, a digital depth the course of the ship and ensure its safety. The navigator is sounder and a Doppler speed log. The communications thus becoming less concerned with the direct control of the suite might include a GMDSS workstation with a ship and more concerned with managing the systems and NAVTEX receiver, a computer weather routing system, a people which do so under their direction. While SATCOM terminal, several installed and portable VHF fundamental navigation skills remain vital, the navigator radios, a closed circuit television system, a public address must become competent and comfortable with the and alarm system and automated systems controlling cargo management of advanced technology and human resources, and machinery operations. With all this technology coming especially in stressful situations. aboard, crew size is decreasing, placing increased responsi- A modern ship's navigational suite might include an bility on each member of the team. integrated bridge system with a comprehensive fleet and Thus, the modern navigator is becoming a manager of 433 434 NAVIGATION PROCESSES these resources, both electronic and human. Of course, they • Heavy traffic have always been so, but today’s systems are far more • Entering a channel, harbor or restricted area complex and the consequences of a navigational error are • Heavy weather far more serious than ever before. The prudent navigator • Fire, flooding, or other emergency will therefore be familiar with the techniques of Bridge Resource Management (BRM), by which they can These and many other situations can increase the de- supervise the numerous complex tasks involved with mands on the time and energy of the navigator, and cause maintaining navigational control of their vessel. them to need additional resources—another watch officer, a Bridge Team Management refers to the management bow lookout, a more experienced helmsman—to take some of the human resources available to the of the workload and rebalance the amount of work to be navigator—helmsman, lookout, engine room watch, done with the people available to do it. etc.—and how to ensure that all members contribute to the There is no strict legal direction as to the assignment of goal of a safe and efficient voyage. personnel on watch. Various rules and regulations establish Bridge Resource Management (BRM) is the study of certain factors which must be addressed, but the responsi- the resources available to the navigator and the exploitation bility for using the available people to meet them rests with of them in order to conduct safe and efficient voyages. The the watch officer. Laws and admiralty cases have estab- terms “bridge resource management” and “bridge team lished certain requirements relating to the position and management” are not precisely defined. For most, bridge duties of the lookout, safe speed under certain conditions, resources consist of the complete suite of assets available to mode of steering, and the use of radar. The maritime indus- the navigator including electronic and human, while bridge try has established certain standards known as Watch team management refers only to human assets, except for Conditions to help define the personnel and procedures to the pilot, who is normally not considered a member of the be used under various situations: team. The resources available will vary according to the size Watch Condition I indicates unrestricted maneuver- of the ship, its mission, its crew, its shoreside management, ability, weather clear, little or no traffic, and all funding, and numerous other variables. No two vessels are systems operating normally. In this condition, alike in resources, for even if two ships of a single class are depending on the size and type of vessel and its alike in every physical respect, the people who man them mission, often a single licensed person can handle will be different, and people are the most important the bridge watch. resource the navigator has. Effective Bridge Resource Management requires: Watch Condition II applies to situations where • Clearly defined navigational goals visibility is somewhat restricted, and maneuver- • Defined procedures—a system—for achieving goals ability is constrained by hydrography and other • Means to achieve the goals traffic. This condition may require additional navigational resources, such as a lookout, • Measures of progress toward goals helmsman, or another licensed watch officer. • Constant awareness of the situation tactically, operationally, and strategically Watch Condition III reflects a condition where • Clearly defined accountability and responsibility navigation is seriously constrained by poor • Open communication throughout the system visibility, close quarters (as in bays, sounds, or • External support approach channels), and heavy traffic. 2702. Watch Conditions Watch Condition IV is the most serious, occurring when visibility is poor, maneuvering is tightly Whenever the navigational situation demands more constrained (as in channels and inner harbors), and resources than are immediately available to the navigator, a traffic is heavy. dangerous condition exists. This can be dealt with in two ways. First, the navigator can call up additional resources, Any watch condition can change momentarily due to such as by adding a bow lookout or an additional watch planned or unforeseen events. Emergency drills or actual officer. Second,
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