maritime

  [1] Background Technology has been central in the development of new tools for   the ship’s navigator and RADAR, the fourth in this series of articles, is a classic example. However it had one major advantage over the earlier tools, it did not require visibility for the navigator to see and identify objects. It could see in the dark and in dense fog, a major benefit for the navigator. It is also one of   the newer tools in the navigators toolbox having been developed in the late 19 th . century. [2] Radio Detection and Ranging (RADAR) was first used for ship detection in the early part of the 20 th . century. Its ability to detect metal objects by returned radio waves from the object was the basis of the modern marine radar. In the early 1960’s I was a newly qualified third officer responsible for the 8-12 watch on the bridge and had a brand new Radar Observers Certificate. The scenario was one that is stressful for a navigator, to say the least! Friday night i...

  [1] Background Whilst latitude had been known and calculated for centuries the same cannot be said for measuring longitude, that essential east and west component of a ship’s position. The early navigators exploring and discovering new worlds relied on what became known as latitude or parallel sailing. Not knowing their longitude they followed a southerly course, often along a known coastline before sailing a constant latitude east or west to their destination. Christopher Columbus’s first voyage illustrates this method. [2] On his first voyage (the blue line on the map), in 1492, he followed the known voyage to the Canary Islands where he carried out repairs before setting out on a westerly parallel course until he discovered an island in the Bahamas. For his return voyage he went northerly until he reached the latitude of Lisbon when he started his easterly latitude sailing. It is important to remember that navigation was relatively crude in this period and charts covered...