Grade 12 – Nautical Science

September 22, 2020

Electronic chart display and information system (ECDIS)

ECDIS is an integrated electronic navigation system which combines the data obtained from a number of electronic navigation sensors and displays it on a video display unit/monitor both in the form of a graphic image and alpha-numeric information. The sensors providing the data inputs to ECDIS are the following: The […]
September 22, 2020

Radio direction finding system (marine radio beacons)

One of the systems which were used along the Namibian and South African coasts was a series of marine radio beacons situated along the coastline and which provided vessels navigating in our waters with a means of obtaining radio bearings. Six of these stations were situated in Namibia and twenty […]
September 22, 2020

Radar transponder beacons

Another system which operated along the South African and Namibian coast was a series of Radio Transponder Beacons. There were five on the Namibian coast and fifteen on the South African coast. The beacons operated in the 10 GHz (10cm) and 3 GHz (10 cm) radar bands. The beacons would […]
September 22, 2020

Decca position fixing system (hyperbolic radio navigation system)

This system was operated by the SA Air Force until the end of 1998. It covered the sea area off Namibia and South Africa and consisted of five Decca “chains”. The chains were situated as follows: Namibia – centred on Usakos. Namaqualand – centred on Noordoewer. Cape Province – centred […]
September 22, 2020

Other electronic navigation systems

Other electronic navigation systems employed in the past include Consol, Loran and Omega (similar to Decca) and the forerunner to GPS, the American Transit system. The latter consisted of 5ive low orbit (1100 kms) satellites orbiting the earth in approximately one and three quarter hours. The system made use of […]