In sub-paragraphs h to k of the procedure, the true bearing is obtained through the use of the A, B, C tables in Nories. There is an alternative method of determining true bearing, namely by calculation. There are two formulas that could be used: Sine formula. In order to convert the azimuth angle to a…
In the Marcq St Hilaire method, a calculated zenith distance or altitude is compared with the observed zenith distance or altitude to obtain an intercept which is plotted from a DR position in the direction of the body’s true bearing. In explaining this method, the altitude and not the zenith distance will be used. The…
During the discussion of the celestial sphere last year, we discussed the spherical triangle PZX which was formed by the projected positions of the celestial pole (P), the observer’s zenith (Z) and the celestial body (X), on the celestial sphere. It was stated that the solution of this triangle formed the basis of all astronomical…
This website has been compiled for the guidance of and use by grade 12 learners taking Nautical Science as one of their secondary school subjects. It follows the approved national curriculum for the subject and comprises three parts, namely Navigation, Seamanship and Communications Metereology is covered on Grades 10 & 11). Although it has been…
QUESTION 1: THE MARITIME WORLD 1.1 Give two reasons for no commercial ships operating with coal-fired boilers now when 100 years ago, it was the fuel used by virtually all ships. [2 x 2: 4] 1.2 Some shipowners are exploring several more eco-friendly ways to power their ships. Give two examples of these “more eco-friendly ways” to…
Develop a Marine Conservation Awareness Programme for your community or school. Include the following in that programme : A short PowerPoint presentation on problems confronting the oceans An attractive poster that draws attention to the problems associated with overfishing or pollution A newspaper article outlining the need for marine conservation A children’s short story abut…
Many people are unaware of the need for marine conservation. Some only show an interest when a shipping accident has caused an oil spill; others are concerned about matters such as pollution (not only oil pollution but also the dumping of non-biodegradable items in the sea), overfishing and poaching. All responsible shipowners and operators are…
Although fishing vessels operate out of all southern African ports, most of the southern African fishing industry is based at ports along the west coast from Walvis Bay in Namibia to Hout Bay near Cape Town, and also operate from Kalk Bay on False Bay, Hermanus and Gansbaai on the southern Cape coast. (See also…
The shipping industry operates in an environment that is subject to weather conditions that range from calm water to enormous swells, strong wind and heavy rain; it operates in temperatures that range from well below zero in the Arctic areas to the heat and humidity of the tropics. Thus the marine environment influences shipping in…
The maritime environment in which shipping operates is fragile and needs to be understood and it needs to be protected. Part of the marine environment is the inter-tidal zone (see the diagram above), an area where humans have greatest contact with the sea. It is here that many swim, surf, fish and have other contact…
