how to plot a course at sea

How to plot a compass course on a chart?

If you which to plot a Compass course on your chart instead of a Magnetic course, you need add the ship's deviation from the table. We designate compass courses with a C at the end instead of an M, e.g. "C 092 C" denotes a compass course of 092.

How do you calculate time on a sailing course?

Write this on your course line as well as e.g. 13 KTS. Multiply the distance of the course by 60, then divide that number by your predetermined speed in knots to calculate the amount of time it will take. Do this and write it on the bottom of your course line in minutes and seconds.

What are sea maps and nautical charts?

Sea maps and nautical charts represent an unbroken thread between all sailors throughout history. Though GPS and other electronics are becoming more and more prevalent, even they are just new version of the consistently refined and improved navigation methods that seafarers have depended on for centuries.

How do you plot a course on a ship?

How to plot a course on a chart:Draw a line from point A to B - using parallel rules, from starting mark to next mark.Check the line for safety - if not, move end mark until you get a safe leg.Measure and mark the heading - transfer the leg to compass.Measure and mark the distance - measure the legs.More items...

How do you plot a chart route?

The first step is to look at the chart, decide on the route, then using a pencil and ruler mark the route from buoy to buoy or chosen position. Each change of course is called a waypoint and its position is marked using a cross with a square around it (the symbol for a waypoint).

What do navigators need to consider when plotting a course?

Mentioned below are important points that must be considered while doing chart plotting to avoid errors and do the job more efficiently.Scale of the Chart. ... Notes of the Chart. ... Chart Symbols. ... Chart Corrections. ... GPS Positions. ... Radar Fixes. ... Visual Fixes. ... Position Circle and Position Line.

How do you use maritime charts?

The scale is represented as a fraction. If the scale is 1:30,000 it means that 1 inch on your chart equals 30,000 inches in real life. That means 1 inch is about 0.4 nautical miles. So one nautical mile will be around 2.5 inches.

What charts do I need for sailing?

Coastal and Approach charts are the ones of interest to most coastal sailors. With more detail and higher resolution, they will cover most of the local hazards. Scale ranges 1:25,000 up to 1:100,000. These are the charts you will use to plan most trips under a day or so that don't head far out of sight of land.

How do you draw a course to steer?

0:253:49RYA Day Skipper: Plotting a course to steer - YouTubeYouTubeStart of suggested clipEnd of suggested clipWe begin by marking the start position for our passage on the chart. We mark this with a symbol forMoreWe begin by marking the start position for our passage on the chart. We mark this with a symbol for a fix a dot. And a circle.

What are the 4 stages of voyage planning?

There are four stages of Voyage Planning that are, Appraisal, Planning, Execution and Monitoring that logically follow each other. An appraisal of all information available must be made before detailed plans can be drawn up and a plan must be in existence before tactics for its execution can be decided upon.

How do you read a sea chart?

Read the chart numbers to figure out the water's lowest depth. The black numbers printed on the chart represent water depth. Each number indicates the "mean lower low water" (MLLW) in an area. This is the average water depth at low tide, so most of the time the water is deeper than what you see on a chart.

Which scale chart is best used when navigating on open sea?

The Nautical Chart. As a navigator, the nautical chart is one of your most important tools. A chart is a graphical representation of part of the earth's surface.

What are the basics of navigation?

Basic NavigationLongitude and Latitude. To be able to describe your position anywhere in the world, you can use Latitude and Longitude. ... Speed & Distance. 1 Nautical Mile = 1852 metres. ... Time. When working out time, it is best to use the 24 hour clock. ... Steering a Course. ... Variation. ... Deviation. ... Relative Bearings. ... Transit Bearing.More items...•

Magnetic Variation

The problem encountered with plotting a course is that the bearing potted will not match what the compass reads while afloat. The north of a compass (or magnetic north) does not agree with the geographic North Pole.

Magnetic Variation (Declination)

The difference between True North and Magnetic North. Changes depending on geographic location.