Terrestrial based tracking with very high levels of GPS accuracy for most aircraft. Some older aircraft use inertial reference units instead of GPS for positions, decreasing positional accuracy.

Satellite based tracking with very high levels of GPS accuracy for most aircraft. Some older aircraft use inertial reference units instead of GPS for positions, decreasing positional accuracy.

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.

Terrestrial based tracking used in light aircraft, such as gliders. Variable levels of data quality based on limited tracking capabilities for gliders. Data provided by the .

3rd party data covering North America and certain oceanic regions around North America, aggregated from different data sources. Provided to Flightradar24 as is with variable quality based on multiple factors.

An aircraft's position may be estimated for up to 240 minutes after coverage has been lost based on the great circle path between the last received position and destination. Accuracy of estimated positions will vary based on time since last received position and flight route.

This aircraft is broadcasting an invalid transponder code due to malfunction or incorrect programming. As the ICAO 24-bit address is incorrect, it's often impossible to identify the aircraft.