Terrestrial based tracking using the time difference of arrival to calculate position. Should give high positional accuracy during most phases of flight, but position errors can sometimes occur. The ground speed is calculated and can sometimes be incorrect, especially during turns and at low altitudes. Vertical speed is also calculated, so errors can sometimes occur. Altitude data come from the transponder and should be correct. Read more
Search cheap flights with KAYAK. Search for the cheapest airline tickets for all the top airlines around the world and the top international flight routes. KAYAK searches hundreds of travel sites to help you find cheap airfare and book a flight that suits you best. Since KAYAK searches many plane tickets sites at once, you can find cheap tickets from cheap airlines quickly.