• Reading almost any book on coastal navigation leaves most people with the impression that the running fix is not used much. This can not be further than the truth. Important to Coastal Navigation I find that while navigating along a coastline, the opportunity to complete a running fix presents itself more often than being able to obtain a two or three bearing fix. Once taken, a bearing to an object is later be “advanced” in time and compared with a new bearing of the same or a different object providing a fix. This new bearing can then be advanced to compare with another object coming into view later. Over time,…

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• The idea of a “Danger Bearing” is a simple one. Unfortunately, as navigators we often try to make is more difficult than it really is. Here we explore what danger bearings are and how to use them as a prudent mariner. A danger bearing does not take into consideration your vessel’s course, heading, or destination. It simply tells you which side of a line you are on, the “safe” side, or the “dangerous” side. It is Like an LOP A danger bearing is similar to a line of position. It is a bearing to an object. However, the bearing line is drawn from known safe water so that it passes…

• Plotting Tool Options There is a wide array of tool options to assist you in navigation plotting. All have pluses to recommend them as your “go to” tool. Unfortunately, all also have cons that make them less desirable or more challenging to use. This tip is specifically how to use navigation protractor triangles (just call them triangles). For a discussion of the plusses and minuses of the other options, check out the lesson on “Navigation Tools – Plotting Tools“ Using Navigation Triangles Why Triangles (aka: What is a Protractor) Before we talk about why I prefer using triangles over the other plotting tool options available to me, let’s talk about…

• Finding Latitude and Longitude Lines of latitude run east and west (across the chart). Lines of longitude run north and south (up and down). Degrees of Latitude Zero degrees of latitude is known as the equator. Latitude goes from zero degrees to 90 degrees north and south of the equator. As can be seen in the image above, Lines of latitude run parallel to each other. There are 60 nautical miles between each degree of latitude. Lines of latitude are a consistent distance apart, so they can be used to measure distance. One degree of latitude can be divided into 60 “minutes”. Each minute of latitude is one nautical mile.…

• What is an LOP In this topic, we discuss “Lines of Position.” A line of position (LOP) is a “line” to or around a target object. When an LOP is determined, you must be somewhere on that line. Because of this two LOPs provides an exact location. In other words, if you are somewhere along each of two different LOPs, you must be located at the intersection. In this case, “X” marks the spot. An LOP can be found a number of different ways. Bearing to an object A Range (two objects in line with each other) Depth contour line on a chart Distance Off an Object Angle off the…

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• The method of determining location used by a mariner is latitude and longitude.  Parallels – Lines of Latitude Lines of latitude run East/West marking off the degrees of an arc between the equator and each of the geographic poles. The equator is 0°. The North Pole is 90°N and the South Pole is 90°S. Lines of latitude are also known as “parallels” owing to the fact that they run parallel to each other moving up and down the globe. Meridians – Lines of Longitude Lines of longitude, also known as “meridians”, run North/South, beginning at one pole, and terminating at the other.  As with any sphere, there are 360° around…

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• Aids to navigation can pretty much be summed up as any object that might be used to aid in the process of safe navigation. Here, we will just be talking about some of the major aids found in the US Coast Guard U.S. AIDS TO NAVIGATION SYSTEM card. ATONs in the United States The U.S. follows a pattern of ATONs known as “Red-Right-Returning.” Lateral Aids Lateral Aids indicate the sides. Most often, the sides of a channel. They generally fall into one of four “types”. Red Marks – right side as seen entering from the ocean (returning.) Green Marks – left side as seen entering from the ocean. Red over…