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Unit 1: Navigation. What is Navigation?. Navigation is the process of monitoring and controlling the movement of a craft or vehicle from one place to another It involves: Gathering information from sources Evaluating the information Making decisions based on the information.
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What is Navigation? • Navigation is the process of monitoring and controlling the movement of a craft or vehicle from one place to another • It involves: • Gathering information from sources • Evaluating the information • Making decisions based on the information
Navigation techniques vary with the type of vessel, conditions and the navigators experience • Navigation is both a science and an art that takes knowledge, skill and practice
Types of Navigation There are 6 main types of navigation: • Dead Reckoning • Piloting • Celestial Navigation • Radio Navigation • Radar Navigation • Satellite Navigation
1. Dead Reckoning (DR) • the process of estimating your position by advancing a known position using course, speed, time and distance to be traveled. In other words figuring out where you will be at a certain time if you hold the speed, time and course you plan to travel.
2. Piloting • Piloting involves navigating in restricted waters with frequent determination of position relative to geographic and hydrographic features. • This method is used when in sight of land
3. Celestial Navigation • uses "sights," or angular measurements taken between a celestial body (the sun, the moon, a planet or a star) and the visible horizon to locate one's position on the globe, on land as well as at sea.
4. Radio Navigation • uses radio frequencies to determine position on Earth. • The basic principles are measurements from/to electric beacons, especially: • Directions • Distances • Velocity (partly)
5. Radar Navigation • Uses a radar to determine the distance from or, bearing of, objects whose position is known.
6. Satellite Navigation • Uses artificial earth satellite systems, such as GPS, to determine position.
Map • A map is a visual representation of an area • It represents selected features of the Earth's surface, drawn to scale.
Maps Include • The graphic representations on maps may consist of: • Lines and symbols of various colors • Drawings of landforms • Photographs with the additions of lines and colors to emphasize features • Maps show land areas, political subdivisions, and topography.
Scale • Many, but not all, maps are drawn to a scale, expressed as a ratio such as 1:10,000 • This means that 1 of any unit of measurement on the map corresponds to 10,000 of that same unit on the ground.
Political vs Physical Maps • Most maps of the world or large areas are either political or physical • Political maps show territorial borders • Physical maps show features of geography such as mountains, soil type or land use
Charts • A chart is a special-purpose map, generally designed for a form of navigation, such as sea navigation. • A nautical chart is a graphic representation of a sea area and adjacent coastal regions.
Depending on the scale of the chart, it may show: • Depths of the water • Heights of land • Natural features of the seabed • Details of coastline • Navigational hazards • Locations of natural and man-made navigational aids