Final answer:
Coast Guard 406 MHz ELTs use the Global Positioning System (GPS) to provide accurate aircraft position information.
Step-by-step explanation:
All Coast Guard 406 MHz Emergency Locator Transmitters (ELTs) are configured to provide position information from the aircraft using the Global Positioning System (GPS). The GPS is a network of 24 satellites that constantly broadcast their position, allowing receivers on aircraft to determine their location with high accuracy. The receivers can convert satellite signals into positions accurate within at least 15 meters or about 50 feet.
In the past, before the advent of the space age, determining a ship's position in mid-ocean was much more complicated and required navigation by using the Sun and the stars for celestial navigation.