Grade 10 – Nautical Science

November 23, 2020

Navigation definitions and concepts

East and West. The earth is a sphere which rotates about its own axis. The direction towards which it rotates is “East” and the opposite direction is “West”. See the sketch below. North and South. The axis of the earth has two poles. The pole to one’s left when facing […]
November 23, 2020

Navigational charts

Navigational charts are produced by the Hydrographic authorities of a country. In our case the authority is the SA Navy Hydrographic Office. The headquarters of the hydrographer is situated at Silvermine in Cape Town. The charts are compiled and printed according to international standards and conventions and are therefore usable […]
November 23, 2020

Passage planning

Need for Passage Planning. Just as you would not make a long journey by car without proper planning beforehand, so is it with sea voyages. In fact it is even more essential. Remember there are no roads at sea and the surface of the sea is not smooth and static. […]
November 23, 2020

Measurement of position and distance on the earth’s surface

So far we have covered the basic definitions and concepts used in nautical navigation. We will now look at a number of simple problems to demonstrate our understanding of these definitions/concepts. This practical assignment assumes that you have access to a physical copy of a nautical chart for the Table […]
November 23, 2020

Measurement of direction – three figure notation

Three figure notation. All bearings and headings (courses) are expressed in three figures. For example: North is expressed as 000°. South is expressed as 180°. North-west is expressed as 045°. Five degrees to the right of north is expressed as 005°. The reason for this is to avoid confusion with […]