Tag: Navigation Tools

My Incredible Adventure- Using Dividers

Posted on by Sharon

Captain Amanda teaches Alice how to measure distance with the dividers
Captain Amanda teaches Alice how to measure distance with the dividers

How to use dividers

Using dividers and the latitude scale on your nautical chart, you are able to measure distance in nautical miles. (Remember, do not use longitudes to measure distance. Longitude lines converge at the poles and the distance between them changes relative to your position on the earth.)

One minute equals one nautical mile. Examine the scale of your chart. In these examples, our chart is in degrees and minutes.

Place one point of the dividers at position A and the other point at at position B. Then, maintaining the spread, measure the distance using the latitude scale. In this case, the distance is 15 minutes or 15 nautical miles. Always use the latitude scale located in the same horizontal region that you are measuring.

My Incredible Adventure- Navigation

Posted on by Sharon

  • Compass
    This is a very important Navigation Tool. Its function is to determine the direction of the course. There are many types of Compasses. Some of these include handheld Compass, marine Compass, Magnetic Compass, and steering Compass.
  • Charts
    A Chart holds a set of information which is valuable and useful in Navigation. Some terms that you may encounter when using Charts are:

    • Projection
      The way a curved surface is represented on paper is called Projection. One example is a Mercator Projection. This is a cylindrical map projection where the meridians are equidistant, parallel, and vertical lines, while the parallels of latitude are horizontal, straight line the spaces of which increase from the Equator.
    • Sounding
      This is a measured depth of the water.
    • Scale
      The Chart can either be small-scale or large-scale. A small-scale Chart covers a large area in less detail and is used in planning, plotting positions, and navigating off shore. On the other hand, a large-scale Chart covers a more detailed projection of small area and is used in coastal Navigation
  • Plotting Equipment
    Navigation also requires a set of equipment for any plotting work on paper Charts. Aside from a Chart table in which you will do your Chart Work, you need Dividers to measure distances on the Charts, Plotter or parallel rulers, and pencils for making marks.
  • Logs
    A Log is a good tool which displays important data such as the distance sailed and speed. Other types of Logs show other information including average and maximum speed reached.

These are the basic tools in Sailing Navigation. There are other devices used in Sailing, depending on the type of Sailboat, weather, and the experience of the sailor when it comes to Navigation.