This article is from WeChat public account: qubit (ID: QbitAI), author: Ming Min, Yuyang, title image from: Visual China
A little-known “niche civil aviation good thing” became popular overnight.
The function of tracking flights in real time attracted 300,000 people last night, which directly caused the traffic to explode on this little broken website and collapsed for a while.
If you Go to bed earlier, and now we can take another look at the interface of this website called Flightradar24.
like That’s right, the map will show all kinds of planes flying in the sky. Select the (small red plane in the picture) you want to query, and you can get detailed flight information and see its real-time flight track (purple line in the picture) on the map. ).
Is it quite convenient? With this artifact, female friends no longer have to worry about me being late for pick-up.
Let’s get down to business, here are some knowledge points: How can Flightradar24 track the route so accurately, even Airbus, Boeing and other companies are using it?
Let’s study together.
Tracking Flights with Open Source Data
In a nutshell, Flightradar24 Mainly using open source data to achieve flight tracking.
According to the official website information, Fligtradar24 combines a variety of data sources, including ADS-B, MLAT, radar data, as well as airline and airport schedules and flights status information, etc.
ADS-B
ADS-B, That is, broadcast automatic correlation monitoring. This is the primary technology used by Flightradar24 to receive flight information.
This is how the technology works in general:
1. The satellite navigation system determines its own position
2. The aircraft regularly broadcasts the position information through the ADS-B transponder installed on the aircraft
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3. The ADS-B ground receiver of Flightradar24 receives the relevant signal
4. These data are updated synchronously to In Flightradar24’s website and app
In fact, ADS-B is not only useful for air traffic control on the ground and tracking sites such as Flightradar24, but ADS-B also provides convenience for the pilots on board.
ADS-B data includes aircraft altitude, heading, speed, and additional information such as conflict warning information and route inflection point information.
And compared with radar surveillance systems, ADS-B data update speed is fast, data accuracy is high, transmission information is rich, installation And the cost of use is also much lower.
Therefore, on an aircraft equipped with an ADS-B receiving device, the pilot can also obtain the traffic information and conduct autonomous avoidance to avoid collision. machine.
Currently, most aircraft in the world are required to be equipped with ADS-B equipment.
Fligtradar24 has the world’s largest ADS-B network with more than 30,000 ground receivers.
MLAT
But not all aircraft are equipped ADS-B devices, if they encounter this non-carrying situation, can also be tracked using MLAT.
MLAT stands for Multilateration, mainly through the time difference of arrival(TDOA)This wireless Positioning technology to calculate the position of aircraft not carrying ADS-B equipment.
In simple terms, MLAT utilizes signals sent by older transponders on airplanes. By measuring the time it takes to receive a signal with multiple receivers, the aircraft’s position can be calculated.
This method requires four or more receiving devices.
In addition to the two data mentioned above, the data sources of Flightradar24 also include satellite data, North American radar data and North American real-time data from the Open Glider Network (OGN).
By the way, Flightradar24 has a lot of fun little features.
For example, click the “3D view” button in the lower left corner.
You can see the 3D effect of the plane flying in the air.
< img class="content_title" height="300" layout="responsive" sizes="(min-width: 320px) 320px, 100vw" src="https://p0.ssl.img.360kuai.com/t01d94b73c2f1b3de8a.jpg" width="600">
PS: Some advanced features require payment.
From a side project to the most popular flight tracking app
Now, both in the Apple App Store, Still on Google Play, Flightradar24 is one of the most popular travel apps with over 40 million downloads.
However, Flightradar24 was originally just a A side project.
Mikael Robertsson(Mikael Robertsson) and Olovo Lindberg from Sweden >(Olov Lindberg)Out of interest, they noticed the ADS-B aircraft signal communication method.
So they bought several small Receivers are mounted on rooftops and can track planes as they fly over Stockholm.
In 2006, they created a website to compare airfare prices, And added the flight tracking function to the website.
Soon, this model attracted many aviation enthusiasts, and some people expressed their willingness to live on their roofs A receiver is installed on the device to collect data for the website.
This further expands the tracking range of Flightradar24.
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By 2009, they officially opened the network to the outside world, making it possible for anyone with ADS- People who accept the device can upload data to them.
In addition, some fans helped them write a software that can get various information from the ADS-B signal.
You can see that the flight’s origin, destination, callsign, location, altitude, airspeed and heading will be displayed on the Flightradar24 official website, and even Aircraft pilot instrument settings, remaining fuel and other data can be provided.
Providing such timely and comprehensive information, Flightradar24 has also attracted many professional aviation people, such as air controllers to check the real-time situation of each aircraft.
Flightradar24 can also be seen in many major news events.
In 2010, a volcanic eruption in Iceland caused widespread flight cancellations in Europe, and many media were using Flightradar24 to track flight information.
In 2014, the Malaysia Airlines MH17 crash occurred, and Flightradar24 also provided a lot of information on the flight on that day.
The occurrence of these two events brought huge traffic to Flightradar24.
According to founder Robertson, the volcanic eruption in Iceland in 2010 affected flight events, and the number of visitors to Flightradar24 exceeded 4 million.
In 2014, there were frequent air crashes, and the number of website visits that year increased by about 50 times.
It was also around this time period that Flightradar24 gradually transformed into commercialization, developed its own APP, and changed the range of signal receivers from Europe is slowly expanding to a global scale.
Additionally, companies such as the Federal Aviation Administration (FAA) have long required all aircraft, including private helicopters, to have a Must be equipped with ADS-B transmitters every year.
Now, Flightradar24 has grown into one of the most popular flight tracking applications in the world. According to the official website, Flightradar24 tracks more than 180,000 flights every day, with more than 2 million daily active users.
One More Thing
Worth a mention Fortunately, due to the wide range of aircraft using the ADS-B system, Flightradar24 filters some data to protect privacy.
However, there have also been accidents. For example, in 2014, the flight route and location information of the special plane taken by the Japanese Prime Minister and other high-level leaders were available on Flightradar24. see directly.
There are many websites with similar functions like Flightradar24, such as ADS-B Exchange, FlightAware, OpenSky Network, Radarbox24, PlaneFinder and so on.
Among them, ADS-B Exchange is one of the more wild ones, it allows users to view the flight information of celebrities, politicians’ private jets, and even military aircraft information. Queried.
As these sites grow, so does a lot of news about private voyages.
For example, it was found that this year Taylor Swift topped the list of celebrities for carbon emissions from flying in a private jet. There are even 19-year-old high school students who have opened more than 30 robot accounts to disclose private jet flight information. Celebrities involved include Musk, supermodel Kari Jenner and more.
Previously, an enthusiast said in an interview that this experience of tracking flight movements gave him a kind of “bird watching”. feel.
This article is from WeChat public account: qubit (ID: QbitAI), author : Mingmin, Yuyang