Use of Global Positioning System navigational aids

  • How GPS works
  • Accuracy
  • Some questions to ask when buying a GPS
  • GPS uses and limitations

The Global Positioning System or GPS is the modern day equivalent of celestial navigation. The sextant has become the GPS receiver and 24 orbiting satellites have replaced the moon and the sun. The United States Department of Defence initially established GPS. When made available to the civilian population, it was immediately recognised by seafarers as the opportunity to abandon their sextants. With the recent reduction in size and price of GPS, more people are venturing into the world of navigation with this handy tool. Before you do however, it is important to understand a few basic fundamentals of their operation and their constraints.