Live Flight Tracking. How does it work?

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10 years 1 month

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For example http://uk.flightaware.com/live/flight/ACA857 I'm curious how it works? Especially how does it determine being pushed from gate, taxiing, landed etc?
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Profile picture for user Matt-100

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7 years 2 months

Posts: 569

The 3 things you mentioned all come from the airport data systems. The same systems that show the flight information on screens at the airport. The actual tracking of the flight in the air is probably done by radar, which is why ocean and remote areas aren't covered.

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10 years 1 month

Posts: 2,535

Airport info sounds likely however for the flight I'm wondering if this site is using some form of telemetry from the aircraft? I watched Flight 858 go into the hold at Heathrow in relative real-time. I say relative as it appeared to lag about 8 mins from actual. However I just noticed that over water the plane has changed to `Estimated` so I guess you are correct about radar. My question would then be is the radar information made public somehow?
Profile picture for user Matt-100

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7 years 2 months

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Most of the major flight trackers (Flight Aware, Flight Radar 24 etc.) have their own private radar beacons to track the aircraft, I know http://www.flightradar24.com/ is real time with the exception of FAA traffic which has a legally required lag of 5 minutes. Edit: my bad, they don't use Radar but ADS-B http://www.flightradar24.com/how-it-works

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9 years 6 months

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From FlightAware FAQ:
Where is this data from? FlightAware compiles, aggregates, and processes data from dozens of government sources, airlines, commercial data providers, as well as FlightAware's proprietary flight tracking network. FlightAware's proprietary algorithms calculate delay and arrival time estimates to offer the most up-to-date and reliable flight tracking data on the Internet. Not all worldwide data sources (e.g., European data) or satcom data are freely available on FlightAware.com due to government regulations or commercial agreements. How does FlightAware handle international flights? What is FlightAware's service area? FlightAware's primary service area includes airspace operated by the United States (including Alaska, Hawaii, Puerto RIco, and Guam), Canada, the Caribbean, Australia, the United Kingdom, and France. Flights in the primary service area support real time maps, departure and arrival information, delays, and more. FlightAware's secondary service covers scheduled major airline operations at any airport in the world. Flights in the secondary service area support departure and arrival information. For some airlines, FlightAware receives satellite position reports from aircraft worldwide. For flights arriving in a service area from outside of a service area, FlightAware will be able to track the flight when it nears a service area. For flights departing a service area, FlightAware will be able to track the flight until it leaves the coverage area. Flights may not be tracked beyond that point unless they enter another service area.

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11 years 6 months

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I use FlightRadar24. It seems to work when aircraft are flying over oceans, unless I've missed something. Given that aircraft are flying over oceans much of the time,that's just as well.
Profile picture for user Skymonster

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15 years 3 months

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Flightradar24 and its equivalent Planefinder work primarily off of ADS-B signals transmitted by aircraft. These signals transmit information such as aircraft identity, location, altitude, speed, heading, rate of climb/decent etc to anyone with a receiver. They are primarily line-of-sght, and thus don't get picked up by anyone when they are transmitted outside of the range of a ground station. Many thousands of aviation enthusiasts have bought their own receivers (typically, Kinetic SBS or AirNav RadarBox) to display real-time aircraft location and identification on their own computers. The operators of FlightRadar24 collect data from many of these enthusiast run devices when they are connected to the internet, and collate the data from multiple devices to present as on their website as a single view with in most locations aircraft being displayed in real time. One exception is in the USA, where the FAA releases radar imagery, albeit with a five minute delay. ADS-B was primarily invented to (a) enhance the information presented to radar air traffic controllers as it transmits much more data than can be collected from a radar head and (b) to provide information from the transmitter to other aircraft as a means of enhancing collision avoidance. ADS-B will eventually be mandated on all aeroplanes that operate in controlled airspace, even GA. The secondary and initiallu unexpected side effect of ADS-B has been that enthusiasts have, through the acquisition of a cheap reciever that can be plugged into PC or through the internet, been able to track aircraft. For registration spotters, ADB-S has been a revelation. Understandably there are some concerns in the industry about the live tracking of flights, especially from a security point of view, and there is still a possibility that ADS-B signals could be scrambled in future, which would render websites such as FlightRadar24 largely obsolete.
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15 years 3 months

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Once out of radar range and the range of ADS-B receivers (typically locations over oceans such as mid-Atlantic), flight positions are estimated and projected rather than "real" and are based on previous tracks and speeds and flight planned routings

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11 years 6 months

Posts: 1,059

Ok, thanks. I get it now. This system seems to work very well.:)