ABSTRACT
The Estimated Time of Arrival (ETA) is simply a product of the Distance, Speed and Time triangle. Once the distance between the two points has been calculated, then the steaming time can be found by dividing the distance by the estimated speed. Where a port is unable to take the vessel at the expected time due to unforeseen delays, the ship's agent will hopefully inform the ship in advance of its original ETA. Because of the differences in the Zone times of different countries, the easiest way to get an ETA is initially to convert the Departure time to GMT (UT). The other concern for the navigator and of great importance to getting the ETA particularly the Date of Arrival correct, is the presence of the Date Line in the Pacific Ocean. At the bottom of the Standard Time pages in the Almanac there is a key relating to symbols within the tables.
