On a typical day, more than 200,000 flights take off and land around the world. This includes commercial, cargo and charter planes — which account for about half of the total — as well as business jets, private aircraft, helicopters, air ambulances, government and military aircraft, drones, hot air balloons and gliders.
Most of them are equipped with a transponder, a device that communicates the aircraft’s position and other flight data to air traffic control, and this signal can be captured with inexpensive receivers based on a technology called ADS-B, for Automatic Dependent Surveillance. -Broadcast.
That’s what flight tracking sites do in a nutshell, giving users a real-time snapshot of everything in the sky (minus a few exceptions).
This is now going far beyond aviation enthusiasts. When a US Air Force plane carrying House Speaker Nancy Pelosi landed in Taiwan in early August, more than 700,000 people witnessed the event as it happened, via flight tracking service Flightradar24.
The plane, a military version of the Boeing 737 called the C-40, departed Kuala Lumpur, Malaysia, before embarking on a circuitous route to Taiwan in order to avoid encounters with the Chinese military, adding flight hours.
That didn’t immediately make it obvious what the final destination would be, sparking chatter online as the plane slowly veered north towards the island.
As a result, it was the most tracked flight of all time on Flightradar24, with 2.92 million people following at least part of the seven-hour journey.
The site, part of a group of popular flight tracking services along with FlightAware and Plane Finder, was founded in Sweden in 2006 “completely by accident”, says FlightRadar24 director of communications Ian Petchenik, as a way of directing the traffic for a flight. price comparison service.
It first gained global recognition in 2010, when the eruption of an Icelandic volcano canceled thousands of flights and attracted four million visitors: “This was certainly our first foray into international events, and how to show air traffic to the public in real time people were thinking about world news,” says Petchenik.
“The number of visitors we got would have brought the site down, so our saving grace was that there was nothing to show but a hole.”
high interest
Prior to Pelosi’s flight, the most tracked flight record on Flightradar24 belonged to Russian opposition leader Alexei Navalny’s return trip to Russia, where he was to be arrested.
The January 2021 flight was tracked by 550,000 people, beating a previous record set in April 2020, when nearly 200,000 users watched a Boeing 777 draw the crescent and star symbols of the Turkish national flag in the skies above Ankara, to commemorate the 100th anniversary of Turkey.
Before that, in September 2017, thousands had watched a brave Delta Boeing 737 fly straight into Hurricane Irma to land in Puerto Rico and take off 40 minutes later for JFK, carefully positioning itself in the gaps between the hurricane’s arms.
Where others have turned back, Delta #DL431 press on. #Sister
📡 https://t.co/XN6E2TcXUN pic.twitter.com/YRXxEduTok
— Flightradar24 (@flightradar24) September 6, 2017
Outside of major events, however, the number of people tracking flights is steadily increasing: “We see many people using the site to track a loved one, track their own flight, or find the arrival flight they are heading to later that day. , to make sure the plane is arriving,” says Petchenik.
“Another use case is people who are very interested in aviation, or really enjoy following certain types of aircraft. They can also go to the airport, open the app and see what’s to come. So you have people who invest professionally in the aeronautical industry, because they own an aircraft and have leased it, or because they have a fleet of aircraft and want to accompany them. Finally, there are people who are professionally invested in having a lot of flight data. airlines, airports, aircraft manufacturers that are using large data sets to gain industry insights.”
How data is collected
To collect the data, Flightradar built its own network of ADS-B receivers, which they now say is the largest in the world with around 34,000 units, even covering remote areas like Antarctica.
About a quarter of the receivers were built by Flightradar24 itself, but most are assembled by enthusiasts who volunteer the data. Because building a receiver is relatively inexpensive — components cost about $100 in total — many have signed up since Flightradar24 began opening its network to the public in 2009.
A dense array of receivers is essential for tracking flights globally, but there is an obvious problem with the oceans, where the network becomes sparse. So how do you get coverage in open water?
“Finding islands wherever we can and making sure we have receivers there,” says Petchenik. “But more recently, we have turned to satellite-based ADS-B receivers to be able to better track aircraft over the ocean. However, the most prevalent data source is still our own terrestrial network.”
Having such a granular and localized amount of data can be useful for getting an early view of emergencies and accidents: “We store everything that comes in on our servers and, if necessary, we can go back to a specific receiver and extract the raw data. This is usually only done if there is an accident or if we have a request from an air navigation service provider or accident investigation agency,” says Petchenik.
Occasionally, data can reveal the cause of an accident before an official investigation does. In the case of Germanwings Flight 9525, which was deliberately taken up a mountain by the co-pilot on March 24, 2015, the data suggested a very clear picture: “One of the parameters that appears in the most complete set of data, which we received in the case of the Germanwings flight, it’s something called the MCP ALT — this is the knob that’s turned to tell the aircraft’s autopilot what altitude to fly. Looking at the data for that aircraft, this altitude value was set to zero. ”
However, not all data is available for all aircraft as this depends on the type of transponders and receivers involved.
Aircraft owners or operators may also decide to prevent their data from being publicly displayed, most commonly for military, government, or private aircraft. For example, they can apply to a program like LADD, for “Limiting Aircraft Data Displayed,” which is maintained by the Federal Aviation Administration: “We respect that list,” says Petchenik.
“It allows operators to have their data displayed differently, anonymously or, in some cases, not displayed. Of the total aircraft we track daily, about 3% have some sort of data display regulation.”
Source: CNN Brasil
