ADS-B is the main source for many live positions
Equipped aircraft broadcast identity, altitude, speed and position. Networks of receivers collect those messages and send them to tracking platforms.
Satellites extend coverage over oceans and remote areas
Space-based receivers can detect ADS-B signals far beyond terrestrial antenna range. That has greatly improved tracking where traditional ground networks were sparse.
Radar and multilateration can fill other gaps
Some services receive radar-derived feeds, while multilateration estimates position from the timing of transponder signals reaching several receivers. The exact mix differs by provider and country.
Schedules and flight plans add context
A position point alone does not explain origin, destination or estimated arrival. Trackers combine movement data with airline schedules, airport information and filed routes.
Displayed time can lag the real aircraft
Data processing, network delays, filtering and local regulations may introduce latency. A public map should not be treated as an air traffic control display.
Some flights are intentionally obscured
Owners, governments or data policies can limit how a flight appears publicly. Military, state and privacy-sensitive operations may therefore be absent, delayed or anonymized.
Tracking sites combine several data sources
ADS-B receivers, satellite feeds, multilateration, radar-derived information and airline schedules may all contribute to the display.
Coverage varies by geography and altitude
Dense receiver networks provide detailed tracks around populated regions, while remote, mountainous or oceanic areas may depend more on satellite coverage.
Displayed positions can be delayed or filtered
Public services may intentionally delay, suppress or limit information for privacy, security or commercial reasons.
A missing track does not prove an aircraft disappeared
The aircraft may be outside coverage, using equipment the service cannot receive or subject to filtering. Air traffic services can have information unavailable to the public.
Call signs and flight numbers can be confusing
The identifier broadcast by the aircraft may differ from the marketing flight number shown on a ticket, particularly on codeshares.
Estimated information should not be mistaken for recorded fact
Arrival times, routes and even aircraft identity may be inferred from schedules or previous data. Consumer tracking is useful but not an official investigation record.
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