(CNN) — On an average day, more than 200,000 planes take off and land in the world. It includes commercial, cargo and rental aircraft – which is half of the total – as well as business aircraft, private aircraft, helicopters, air ambulances, government and military aircraft, drones , hot air balloons and gliders.
Most of them are equipped with a transponder, which communicates the aircraft’s position and other flight data to air traffic, and that signal can be captured with receivers. easily thanks to a technology called ADS-B, for Automatic Dependent Surveillance-Broadcast. That’s what aerial photography sites do in a nutshell, giving users a real-time picture of everything in the sky (minus some exceptions).
An ADS-B receiver made by Flightradar24.
Thanks to Flightradar24
The plane, a military version of the Boeing 737 known as the C-40, left Kuala Lumpur in Malaysia before starting a detour to Taiwan, in order to avoid encounters with the Chinese military, adding hours of flight time. It was not immediately clear what the final destination would be, sparking internet chatter as the plane slowly moved north towards the island. The result is the most watched flight of all time on Flightradar24, with 2.92 million people following part of the seven-hour journey.
The site, part of a group of popular flight tracking services including FlightAware and Plane Finder, was founded in Sweden in 2006 “by accident,” says FlightRadar24 communications director Ian Petchenik. , as a way to drive the car to a flight. price comparison service.
Interest is growing
Before Pelosi’s flight, the top flight story on Flightradar24 was about Russian opposition leader Alexei Navalny’s return trip to Russia, where he was detained. The January 2021 flight was seen by 550,000 people, beating a record previously set in April 2020, when nearly 200,000 users watched a Boeing 777 fly the flags of the national flag Turkish in the sky above Ankara, to celebrate the 100th anniversary of Turkey. government authority.
Before that, in September 2017, thousands watched a brave Delta Boeing 737 fly directly through Hurricane Irma to land in Puerto Rico, and take off 40 minutes later for JFK at positioning itself in the gaps between the arms of the wind.
Apart from the big events, however, the number of people following the planes is still increasing: “We see a lot of people using the internet to follow a loved one, track their own flight, or see which flight they’re on. go later that day, make sure the plane arrives,” Petchenik said.
“Another use case is people who are very interested in aviation, or who want to follow certain types of airlines. They can go to the airport, pull up the app and see what’s coming up. . aviation industry, because they own and lease aircraft, or because they have aircraft fleets and want to monitor them. airlines, airlines, aircraft manufacturers that use large data sets to gain professional knowledge.”
How data is collected
To collect the data, Flightradar has built its own network of ADS-B receivers, which they claim is the largest in the world at around 34,000 units, covering the places as far away as Antarctica.
Flightradar24 has hosts all over the world, including places as far away as Antarctica.
Thanks to Flightradar24
About a quarter of the receivers are built by Flightradar24 itself, but most are assembled by interested people who provide data on a voluntary basis. Because it’s relatively easy to build a receiver – parts cost around $100 – many people have signed up since Flightradar24 opened its website to public in 2009.
The number of receivers is important for tracking aircraft worldwide, but there is a problem with oceans, where the network is limited. So how do you get coverage on the open water?
“By finding islands wherever we can and making sure there are hosts there,” Petchenik said. “But recently, we have turned to satellite-based ADS-B receivers, which can accurately track aircraft over the ocean.
Having such a detailed and large amount of data can help in the early detection of accidents and disasters: “We record everything that enters our servers and if necessary we can go back to a specific receiver and extract the raw data. It will only be done if there is an accident or there is a request from an air traffic service or an accident investigation branch,” said Petchenik.
Not all data is available for each aircraft, however, it depends on the type of transponders and receivers.
Aircraft owners or operators can decide to prevent their data from being disclosed to the public, which is common for military, government or private aircraft. For example, they can sign up for a program like LADD, for “Limiting Aircraft Data Displayed,” maintained by the Federal Aviation Administration: “We maintain that list,” Petchenik said. .
“Users can report their data independently, anonymously or, in some cases, not disclosed.
Top photo: A Boeing C-40C carrying US House Speaker Nancy Pelosi takes off from Taipei Songshan on August 3, 2022, a day after Flight SPAR19 became Flightradar24’s most popular flight .