Image: Screenshot, ADS-B Exchange
In 2019, GIJN first launched its guide to planespotting and flight tracking around the world. In the wake of the 2022 invasion of Ukraine, which led to a great migration of Russian oligarchs and their assets, as well as Elon Musk’s efforts to block bots from tracking planes in real time on Twitter, we’ve now updated this reporting guide to account for these recent developments. GIJN is grateful for expert contributions from Emmanuel Freudenthal, a freelance journalist and director of Dictator Alert, in updating this guide.
Tracking airplanes is an invaluable investigative tool.
Investigative journalists have used information about airplanes to uncover corruption, follow wars, track government officials, and point out the levels of greenhouse gasses emitted.
All aircraft have unique identifying numbers that can be used to track their flights and to identify their owners. Well, sometimes.
Flight information is available from commercial and nonprofit organizations who assemble and make available vast amounts of flight data. This makes it possible to follow particular planes, watch specific locations, identify patterns, and more.
Planespotting is feasible because of location identification systems that track flights. One primary technology is ADS-B, which stands for Automatic Dependent Surveillance-Broadcast. ADS-B signals are public and can be followed by amateurs with inexpensive ADS-B tracking stations ($10-$200).
The flightpaths are posted on many websites. This makes basic tracking fairly straight-forward. However, much more sophisticated information can be obtained by analyzing the raw data with a computer to detect patterns and create alerts.
Multiple complications can impede plane-tracking. Pilots can switch off the tracking signals. Depending on national laws, some planes do not need to share their flight coordinates in some areas. Tracking military planes presents special challenges (but is not impossible). In the United States, regulations facilitate anonymous flights by private jets. And in many parts of the world, ADS-B coverage is limited because of a lack of receiving stations.
The fascination of tracking planes has attracted many amateurs (known as “planespotters” or “aviation geeks”), a dedicated community that is a potential resource for reporters. Some planespotters post themselves near airports to take photos and videos of unusual planes. There’s even a website called Airport Spotting that includes information on where to stand at airports worldwide.
Other spotters rely on their computers. Keeping tabs on the movements of celebrities, business executives, and political figures is popular. Some spotters closely watch flights in war zones.
The work of one planespotter made headlines because he irritated billionaire Elon Musk.
Jack Sweeney, a University of Central Florida sophomore, created a Twitter bot to post about the whereabouts of Musk’s main jet (N628TS). One of Musk’s first moves as the new owner of Twitter was to shut down Sweeney’s feed, as well as those of other spotters and the company that supplied him with data.
Sweeney moved to a subreddit account (r/ElonJetTracker) and then reappeared in a new incarnation on Twitter (@elonjetnextday). His Twitter feed now has a 24-hour delay to comply with a new Twitter rule banning posts with real-time location information.
Twitter in early February created another impediment, announcing it will charge for its application program interface (API). Many planespotters post information for fun, not profit, and in reaction to Twitter announcement they predicted that the news costs would reduce their activity.
Primary Sources for Flight Information
Real-time flight information is widely available, much of it for free.
Tracking sites vary in their features. Subscriptions and/or fees are often required for historic data, for example. However, the costs can be pretty low (US$5-$10 a month) for basic information and more for higher value features.
These websites massively rely on enthusiasts who have installed antennas all over the world. Those who “feed” the websites with information from their antennas get free access to the most expensive subscriptions.
Pro bono note: Some tracking sites give journalists a break and provide free guidance. It doesn’t hurt to ask. Also of potential use, some sites have associated chat boards and instructional blogs.
Here are the main sites for tracking planes:
ADS-B Exchange – This site provides information about more flights than other flight-tracking services and is preferred because it does not filter out information about US aircraft that have requested anonymity under US regulations. (More on this below.) It is possible to look up the historical flights of any plane for free. Look at the tracking map, then click or search any plane. On the left panel, look for “history.” Requests for raw data usually require payments. For map help, look here. In January 2023, ADS-B Exchange was sold to JetNet, worrying some users, although JetNet pledged continuity.
Icarus Flights – This flight-tracking tool created by nonprofit Center for Advanced Defense Studies (C4ADS) uses ADS-B Exchange data and adds special features. Among other things, users can monitor specific areas, track flight activity by internationally sanctioned aircraft, and query aircraft ownership data. Icarus Flights is publicly accessible, but investigators interested in using it must contact C4ADS for access to its free service.
The OpenSky Network is a nonprofit association based in Switzerland that says it has the largest air traffic surveillance dataset of its kind because “we save every single message we ever receive from a plane,” one of the volunteers told GIJN.Under Aircraft Database, a search on tail numbers will show registration information about the plane, recent flight history and whether it is in the air. In the Explorer feature, searches show planes in the air. There’s also a 30-day history on all aircraft tracked. Another feature is a list of all emergency alerts.
OpenSky is geared toward academics and nonprofits doing research, but has aided journalists with clearly-defined requests and teamed up with media for visualizations “and other things that benefit us through increased exposure.”
Since JetNet’s purchase of ADS-B Exchange, two new sites have emerged, both with significantly fewer feeders and thus less coverage, at least as of early February 2023, and promising to be unfiltered.
Theairtraffic.com – A site begun by Jack Sweeney “and members of the Ground Control Discord server” with a pledge “always to be open and unfiltered.”
Adsb.fi – “A community-driven flight tracker, with over 500 active feeders around the world” promising “open and unfiltered access to worldwide air traffic data.”
Also new in 2023 is JetSpy, a platform that tracks US private jets, including those having anonymity under US regulations. JetSpy requires a subscription.
Other Tracking Sources
Quite a few tracking services offer real-time tracking maps and show the plane’s recent trips for free, and more.
However, these flight-tracking services honor requests to remove any aircraft whose owner asks for it. Nevertheless, their coverage is much better than ADS-B Exchange in some parts of the world (e.g. Africa and South America).
Some options, such as notification of when a plane takes off and access to historic flight data, are fee-based.
There are also other sites catering to commercial air travelers.
In addition, there are some useful specialty sites. These include:
- Dictator Alert – A project that tracks the aircrafts of authoritarian regimes all over the world and runs several Twitter bots that announce when these aircrafts land in Paris, London, Geneva, or the EuroAirport in Basel-Mulhouse-Freiburg.
- Bellingcat – An open source database to track “noteworthy flights to and from the country’s airports in a bid to better understand the recent and evolving dynamics in Kazakhstan.”
- Advisory Circular Bots posts when aircraft are flying in circles over cities around the world, including Los Angeles, Baltimore, Portland, Minneapolis, and London.
A few of the many prolific Tweeters are: Evergreen Intel @vcdgf555, Gerjon @Gerjon, Aircraft Spots @AircraftSpots, SkyScanWorld @scan_sky, and Avi Scharf @avischarf.
Also see the Bellingcat Discord channel on ships and planes.
Basics of Tracking
The tracking websites display information to identify the aircraft.
One identifier is known the “hex code” (though sometimes called the S-mode or ICAO). This series of six or seven letters and numbers is derived from 24-bit addresses assigned to governments by the International Civil Aviation Organization (ICAO), which means it’s possible to know the country an aircraft is registered in with the code. The hex number will not usually change unless the plane is sold. In principle, it’s a unique identifier for the plane. and it’s the information received by the tracking antennas.
Second, all aircraft have (or should have) physical markings or “tail numbers” located near the rear of the plane, painted at least 12 inches high for visibility. These numbers are short alphanumeric strings that begin with letters indicating the country in which the plane is registered, (N for US, D for Germany, etc.). Wikipedia has a handy list of aircraft registration prefixes. That’s followed by a few numbers and/or letters specific to the aircraft. (Military aircraft use different ID systems.)
Also be aware of “call signs.” The call sign is more or less whatever the pilot decided to enter for that flight. On commercial flights this will be the flight number like DAL307 for Delta Airlines flight 307 from Honolulu to Minneapolis.
The hex codes and registration numbers are key to finding ownership information. In France, for private aircraft, the call sign is often the aircraft’s registration. For high-ranking civil servants, the call signs sometimes change, such as CMR001 for the president of Cameroon, or COTAM001 for the French one.
The Challenge of Identifying Owners
Identifying aircraft owners is possible, but sometimes difficult.
Most countries do not make public their national “registries” of ownership. Many planes are registered in countries that guarantee anonymity, like Aruba (more on this below). Registration does not need to take place where the plane’s owner lives.
About 60 governments make public some ownership information. Some are fairly user-friendly, allowing online searches and downloads. Some, like the UK and US, provide extensive information on the plane’s owners and even any physical changes made to it.
But even when information is available it is skeletal: just the type of plane and the owner’s name. And while some registries are updated daily, others get recharged only monthly or annually.
Ownership information may be disguised. In many cases, the listed owner is a shell corporation or a plane management company, making further research necessary to ascertain who actually own the aircraft. In the United States, the government permits foreign owners to transfer titles to a US trustee.
Some of the tracking websites include ownership information, although the sources are not usually given, and it may be behind a paywall.
Some other things to remember:
An aircraft’s owner is not always on board. Sometimes the jets are rented or traveling to maintenance sites. The fact that a plane owned by Elon Musk takes off doesn’t mean that he’s on it. Passenger “manifests” are not publicly available, so identifying passengers is difficult. To confirm who is sitting inside, either social media digging or old-school journalism is usually needed. Direct observation may yield results, and there are many people working in airports who might talk. Alternatively, passengers might show off on Instagram thus providing the information themselves.
Sources for Registration Information
Here are some resources with ownership information, with the various permutations of free and subscription information.
Here are links to some of the searchable national registries:
- US – Federal Aviation Administration (FAA)
- Australia – Civil Aviation Safety Authority
- United Kingdom – Civil Aviation Authority
A few other possibilities:
- Wikipedia hosts a list of national aviation authorities.
- CorporateJetInvestor, in its Official Guide to Airplane Registration 2023, provides summaries of national registration requirements.
- RussianPlanes.net is a searchable site about Russian aircraft. The site has a note: “Until the completion of the special operation of the Russian Federation in Ukraine, photos of the state aviation of the Russian Federation are not published on the site.”
Special Sites on Tracking Military Flights
The general search sites listed above cover military flights. ADS-B Exchange has a filter that shows only military aircraft.
Here are a few other websites that specialize in tracking military flights:
ADS-B.NL is a site based on real-time data from ADS-B Exchange that focuses on tracking military aircraft worldwide.
Radarbox allows some free searches and allows you to build your own widget to be able to track live flights. To protect the operational security of military operations, as well as the privacy of certain private jet operators, Radarbox either blocks or censors their tracking.
Scramble has databases about different aircraft of the air forces in Europe, the US and Canada, plus some about air forces in South America, Africa and Asia. The site is maintained by the Dutch Aviation Society and has active forums. Scramble also hosts The Soviet Transport Database.
Planeflightracker specializes in NATO and Russian military aircraft.
Aircraft Serial Number Search allows look-ups of US military planes and is maintained by expert Joe Baugher, “an aircraft serial number freak.” His website also has an amazing collection of Aviation Sites.
Two websites with large archives of aircraft photographs are:
Amateur planespotters frequently take photos and videos and disseminate them on social media.
Many of the flight-tracking websites include photos, too.
Understanding the Tracking Systems
Once airborne, planes are tracked in several ways. The newest system, being adopted internationally, is ADS-B, Automatic Dependent Surveillance-Broadcast, and provides the richest information.
To step back, here’s a quick look at the radar-based systems in use for decades:
“Primary” radar detects and measures the approximate position of aircraft using reflected radio signals. This is like that green bleeping screen in the movies.
“Secondary Surveillance Radar” relies on a process in which information is transmitted back from each aircraft when it receives a radio signal. The response contains identification information (the ICAO hex code) and the aircraft’s altitude, but does not provide location information. The location can be determined, however, when the transmissions are received in multiple locations. These are combined through a process called multilateration (MLAT) to estimate the position of the aircraft. (Here’s a longer explanation with a graphic.)
ADS-B allows far greater frequency, precision and coverage, at lower cost. With ADS-B, onboard equipment determines an aircraft’s position via satellite navigation and every half second transmits that GPS information, along with information including altitude, speed and heading, plus the identification code. This is called “ADS-B Out.” A take-off or landing can be inferred based on speed, altitude, and location.
The ADS-B record isn’t always complete. There are dead zones where no receivers exist, such as for deserts, oceans, and polar ice caps. Coverage is incomplete for much of Africa and spotty for Latin America.
The disruptive element of ADS-B is that the signals can be picked up with equipment costing for as little as US$20. The unencrypted signals, transmitted at a frequency of 1090 MHz, can be received within a radius of about 200 miles as long as the plane is within the antenna’s line of sight. There are tens of thousands of these receivers now in existence, mainly operated by amateur aviation enthusiasts who resend the signals to commercial and nonprofit tracking services, sometimes for modest remuneration.
ADS-C is satellite tracking, and it’s just used by some of the larger commercial planes. It’s important to be aware of this source of data while looking at the coverage maps of tracking websites because the ADS-C planes might make the coverage look better than it actually is.
Some of the tracking services will subsidize installation of an ADS-B tracking system and trackers may get free data.
Using Coding to Research Flights
A lot can be gleaned from using the basic tools on flight tracking sites.
However, more ambitious projects will require getting access to data and refining it with custom programming. The data from the major tracking services, as previously noted, is possible, usually for a fee. Many sites provide application programming interfaces (APIs) to facilitate use of the information.
To work with bulk flight tracking data you will usually need some expertise with a programming language like R or Python to process and analyze it. In some cases , you can also just plug a flight path into Google Earth.
Here’s a tutorial by Geodose on how to create a simple flight tracking with Python and a later update on how “to make it more beautiful, with a more advanced approach using Pandas and Bokeh.” And here’s a guide to writing a program to automatically gather data about nearby aircraft using the OpenSkyNetwork API.
One expert on using flight data is Peter Aldhous, formerly of BuzzFeed News, who used data provided by Flightradar24 in a notable investigation.
In 2016, Aldhous wrote “Spies in the Skies,” showing that planes operated by the FBI and the Department of Homeland Security routinely circle over most major US cities. Later he used machine learning to identify further spy planes, by training an algorithm on the data for FBI and DHS planes. (For more details see this explanation.)
Sometimes you can find ready-made programs on GitHub that can help you analyze the data, but it’s likely you’ll still need some coding skills.
In addition, here’s a practical suggestion from a planespotter about how to use ADS-B Exchange.
I group hex codes together on ADS-Bx using the ‘multiple airframes’ function and I save the URLs in favorites tabs for easy access. This gives me a 24 hour window into what those airframes are doing. I don’t there is a limit as to how many you can group, but it will crash your computer if you do more than, say, 500 at once.
This saves me enormous amounts of time. It also snags hex codes throughout the day where they might only be received for a few seconds, thus proving they were in the air, for example. This is critical in areas where there is not such a robust network of receivers (eastern Russia, Africa, etc.)
Working Around US Flight Secrecy Programs
The US government has two programs designed to allow anonymous flight by private planes while in US airspace. While these have frustrated trackers, the protections are not insurmountable.
It’s easiest to work around the Limiting Aircraft Data Displayed (LADD) program. LADD allows US aircraft owners to have their flight data filtered from the data distributed by the Federal Aviation Administration. Because ADS-B Exchange does not use the FAA data, it identifies all LADD flights. Also, here’s a frequently updated LADD List, unofficial, but based on FAA information.
A second program was begun after private plane owners lobbied for a more secure system. Under the Privacy ICAO aircraft address (PIA) program, owners can request that the FAA assign them a temporary hex code that isn’t associated with their tail number. The code lasts for 60 days, and can be changed this as frequently as every 20 days.
The US government’s PIA program has presented some obstacles for trackers, but they have developed a variety of workarounds. Even though not many owners have taken advantage of the program, their desire for anonymity attracted attention. There’s a Facebook site called PIA Busters.
How do you know if a plane is using a PIA code? ADS-B Exchange has a filter for “PIA.” Click it and see PIA flight, usually only a handful of such flights.
Knowing the PIA code, experts suggest a number of ways to figure out what plane it is. Most of them are less technical than behavioral.
- Watch for PIA plane’s patterns and look for familiar routes and destinations. (Collect them on a spreadsheet.)
- Use clues from social media or news accounts to correlate the plane’s movements with a possible person.
- Rely on visual observations on the ground (and via live web cams at airports) consistent with the PIA plane’s movements to confirm the identity of the plane. The number painted on the side of the plan doesn’t change.
- Check ACARS messages which may provide identifying information. (More on ACARS below.)
- Enter the PIA number in other search sites because sometimes glitches expose useful information.
There’s a possibility for further international restrictions, however. For instance, Saudi Arabia in late 2022 tabled a proposal at ICAO “suggesting a controlled level of privacy measures.” No action has been taken on it as of early 2023.
Using FOIA in US to Get Flight Data
Another way to obtain flight data in the United States is to file a Freedom of Information Act request with the Federal Aviation Administration. Requests can be sent to this email address: email@example.com
Ask for “TFMS repository flight records for aircraft with tail number” and give the tail number. TFMS is the Traffic Flow Management System repository. Also set a time frame such as “…from Jan. 1, 2023 through the date of fulfillment of this request.” Ask that it be provided in electronic format. The data provided includes flight information not obtainable through the flight tracking services if the owner exercised his or her blocking option.
Here’s an example of what can be obtained, in this case by ProPublica reporter Justin Elliot for a 2020 story, Steve Bannon’s Use of Private Jet Linked to Chinese Businessman Could Violate Campaign Finance Law.
Tracking Radio Messages – ACARS
Another way to track planes is to follow the short text messages between aircraft and air traffic control (ATC). The radio transmissions system is known as ACARS the Aircraft Communications Addressing and Reporting System. (See a detailed description and video or watch a less technical video.)
The unencrypted transmissions mainly describe flight plans but also can be about mechanical issues. ACARS messages were monitored extensively by observers of the US pullout from Kabul in 2021.
Interpreting the messages is a challenge because lots of short-hand jargon is used. Here’s a blog post that gives just a taste of the abbreviations, such as “ATB: Air Turn Back” – when the captain decides to return to the departure airport instead of continuing to the destination. And another article with some examples. You’re likely going to need an expert to decipher extensive ACARS conversations.
The messages can be picked up with ground or satellite receivers and an international collection has been created by Airframes.IO, who tweets as @thebaldgeek and @AirframesIO. The ACARS messages are posted in near real time. They zip by on the “Messages” page, but can be searched.
Another site, LiveATC.net, links to live air traffic communications from live ATC radio traffic from around the world. LiveATC.Net provides both live and recorded ATC audio transmissions with archive retrieval.
Aviation Safety Records Available
Accident reports might provide additional ownership detail. National agencies in charge of flight safety may disclose records of crashes and inspections.
The Aviation Safety Network (ASN) is a private, independent initiative that maintains an online database on accidents and safety issues with regard to airliners, military transport planes and corporate jets. ASN has an international list of accident investigation boards.
The Aviation Herald reports on all kinds of incidents and accidents worldwide.
For accidents in the US, the responsible agency is the National Transportation Safety Board.
Other US agency records, such as purchasing and contracting records, may offer potential sources of information on government planes. FAA registration files show changes made to the aircrafts, including the addition of night-vision cameras.
US Secrecy Tricks
In the United States, investigative reporters have explored how some owners have registered their jets via banks or trusts to avoid identification.
The US government permits foreign owners to transfer titles to a US trustee — a system ripe for abuse. For example, more than 1,000 aircraft have addresses of trusts at the Aircraft Guaranty Corp., all in Onalaska, Texas, a town without an airport, as reported by the Dallas TV station WFAA.
The Boston Globe exposed the scope of disguised registrations in a series, “Secrets in the Sky.” Its Spotlight team investigation has found that, thanks to lax oversight by the FAA, drug dealers, corrupt politicians, and even those with links to terrorism can register private planes and conceal their identities.” The ownership of more than one out of every six registered planes in the US is untraceable, according to The Globe.
Leasing Poses Another Complication
When jets are leased, a common practice, it is nearly impossible to learn who is paying for a specific flight.
This was the experience for reporter Erdélyi Katalin from the Hungarian investigative site Átlátszó when she started asking about the use of a private jet by Prime Minister Viktor Orbán. Her investigation found that the jet was registered in Austria. Who paid for the flights is unknown; the jet is operated by International Jet Management GmbH, an Austrian company specializing in operating business jets.
GIJN published an article by Átlátszó reporters describing their investigation, “How They Did It: A Private Yacht, a Luxury Jet and Hungary’s Governing Elite.”
Favored Countries for Registration
Registration need not take place where the plane’s owner lives. And planes can be re-registered (sometimes with ID number changes).
CorporateJetInvestor, in its Official Guide to Airplane Registration 2023, describes national rules on registration of planes, and the website aggregates aviation business news. Ease of registration, privacy and tax benefits are key considerations.
The Isle of Man is one popular aircraft registration jurisdiction, providing a way to escape EU taxes, according to a report by the International Consortium of Investigative Journalists.