The Tail Number in Public Skies, the College Student Who Tracked a Billionaire's Gulfstream, and What the ADS-B Transparency Gap Means for Every Pilot With a Squitter

Your ADS-B Out transmitter broadcasts your tail number, GPS position, altitude, speed, and groundtrack 12 times every second on an open radio frequency. Within seconds, that data is likely appearing on publicly accessible websites viewable by anyone in the world. Most pilots have no idea this is happening - or that the FAA has built formal tools to address it.

How ADS-B Became a Public Surveillance Network

Automatic Dependent Surveillance-Broadcast operates on two frequencies in the United States. Aircraft in Class A airspace use 1090 MHz, the ICAO international standard. General aviation aircraft below 18,000 feet have a second option: 978 MHz, using a format called Universal Access Transceiver (UAT).

Either way, ADS-B Out is designed to announce your presence constantly. Every transmission includes your registration, precise GPS position, speed, altitude, and a timestamp accurate to a fraction of a second. It is a cooperative surveillance system - you tell the network where you are, and the network tells controllers, other pilots, and anyone else who is listening.

The mandate did not fully anticipate how large that “anyone else” group would become.

How Commercial Tracking Networks Were Built

When the FAA began deploying ADS-B infrastructure in the early 2000s, the plan was a government-run system: roughly 700 ground stations receiving broadcasts, routing data to ATC, and uplinking traffic and weather back to equipped aircraft. That official network worked as designed.

Simultaneously, hobbyists discovered that software-defined radio receivers could pick up ADS-B signals directly - and started sharing the data online.

FlightAware launched in 2005, founded in Houston by Daniel Baker. It began with FAA-licensed commercial flight data, then built a receiver network supplemented by volunteers who fed data back in exchange for premium account access. Flightradar24 followed around 2006 in Sweden, founded by Mikael Robertsson and Olle Ronnang, using the same crowdsourced model.

By January 1, 2020, when the ADS-B Out mandate took full effect, Flightradar24 alone had accumulated tens of thousands of receiver stations worldwide. Anyone could open a browser, type in a tail number, and watch an aircraft move across a map in near real time - altitude, speed, aircraft type, origin, destination, all of it.

The College Student Who Tracked a Billionaire’s Jet

Jack Sweeney, a University of Central Florida student, began building automated tracking bots in 2021. He created one to follow the Gulfstream G650 operated by a prominent technology executive and posted the aircraft’s real-time location to a public social media account. The account grew rapidly. He built similar trackers for other public figures.

Sweeney was not hacking anything. He was querying the same ADS-B data that Flightradar24 and FlightAware make available through their public APIs. The aircraft was broadcasting on 1090 MHz like every other equipped airplane. Receivers aggregated the data. The public API made it queryable. Sweeney wrote a bot. The bot posted the dot.

The story became international news when the executive acquired a major social media platform and subsequently removed Sweeney’s accounts from it. The aviation dimension - that a cooperative safety technology had become an open personal tracking system - was largely missed by mainstream coverage.

The FAA’s Pre-Existing Privacy Tool: LADD

The FAA had been wrestling with this problem since before ADS-B existed. The Limiting Aircraft Data Displayed (LADD) program was created when the FAA began licensing domestic flight data to commercial entities. Under LADD, an aircraft operator can request that their data not be shared with companies that license FAA flight data. Search a LADD-blocked tail number on FlightAware and you receive a generic message instead of a track.

LADD worked reasonably well in a radar-based world. The FAA owned the radar data and controlled distribution. An opt-out request simply excluded your data from commercial feeds.

ADS-B broke that model. The data is no longer sourced exclusively from FAA radar returns - it comes from independently operated receivers worldwide. A LADD request tells the FAA not to share your data. It does not reach a receiver in someone’s backyard. Operators who filed LADD requests and believed they had opted out discovered that Flightradar24 was still displaying their aircraft in real time via independent receiver coverage. The opt-out was only partial.

How the PIA Program Actually Works

The FAA’s technical solution is the Privacy ICAO Aircraft Address (PIA) program, published in final rule form in 2020. Your ICAO aircraft address is the unique identifier hardcoded into your avionics, directly correlated to your tail number in the public FAA aircraft registry.

The PIA program issues participating aircraft a temporary, rotating ICAO address that changes on a set schedule. Instead of broadcasting your permanently assigned identifier, you broadcast a rotating address not correlated with your tail number in any public database. To an independent receiver, you appear as an aircraft with an unrecognized address. FAA ATC retains the ability to correlate the PIA address back to your actual registration, so controllers always see you and can identify you.

What PIA changes is the commercial and public aggregation layer. A member of the public cannot open a website, type your tail number, and watch your position update 12 times per second. The signal chain between your transmitted identifier and your registered identity is severed.

What PIA Does Not Do

PIA does not make you invisible to air traffic control. It does not affect how TCAS or other traffic advisory systems see you. Your aircraft is still broadcasting ADS-B, you still comply with the mandate, and you still appear on controller scopes. PIA also does not prevent someone from knowing an aircraft is present in an area - it only breaks the correlation between the transmitted signal and your registered identity.

For most general aviation pilots, PIA is not necessary. The use cases are specific: corporate flight departments carrying executives with security exposure, law enforcement aviation units, individuals with documented safety concerns about their movements being tracked.

The Fundamental Engineering Tension

ADS-B is a cooperative surveillance system. Its safety benefits - collision avoidance, traffic awareness, oceanic and remote coverage - depend entirely on participation. The mandate exists because the system only works if everyone broadcasts. If privacy mechanisms make broadcasts untrackable in any meaningful way, the collision picture that makes the system safe begins to degrade.

The FAA’s current framework threads that needle. You must broadcast accurately. ATC retains full identification capability. What the PIA program limits is the commercial and public aggregation layer. Safety surveillance stays intact; consumer-facing tracking becomes opt-outable.

The commercial tracking companies have largely cooperated. FlightAware and Flightradar24 both participate in the LADD program for FAA-sourced data and honor voluntary blocking requests from aircraft owners - even when independent receiver coverage would technically allow them to display the data. This is not legally required; it is an industry norm that emerged as the privacy conversation became loud enough to create business liability.

The OpenSky Network, an academic and research-oriented ADS-B aggregator based in Europe, takes a different position, with access policies for raw historical data that diverge from commercial operators. This remains an ongoing point of discussion within international aviation standards bodies.

What This Means for You as a Pilot

If you fly an aircraft with ADS-B Out - which since January 1, 2020 means nearly all pilots operating in mandate-covered airspace - you are participating in a surveillance network that is simultaneously one of aviation’s greatest safety achievements and one of its least-discussed operational realities. The same signal that gives you a traffic picture in the cockpit gives anyone with a browser a near real-time view of your position.

Your flights are generating a permanent, queryable record in commercial databases. That record exists regardless of whether you know it. Understanding the tools available - LADD and PIA - means you can make an informed decision about your own operation.

The FAA has detailed guidance on both programs at faa.gov. The Aircraft Owners and Pilots Association (AOPA) has published practical guidance on LADD and PIA applications. The MITRE Corporation, the federally funded research center that handles significant aviation systems architecture work, has published technical analyses of the PIA architecture for those who want to understand the cryptographic side of how rotating addresses are managed.

Key Takeaways

• ADS-B Out broadcasts your tail number, position, altitude, and speed 12 times per second on open radio frequencies accessible to anyone with a $30 receiver.
• Commercial networks like FlightAware (founded 2005) and Flightradar24 (founded 2006) built global crowdsourced receiver coverage that made any equipped aircraft publicly trackable in near real time.
• The FAA’s LADD program blocks your data from FAA-licensed commercial feeds but does not reach independent receiver networks - it offers only partial protection in the ADS-B era.
• The PIA program, published in 2020, issues rotating ICAO addresses that sever the public correlation between your broadcast and your registered identity, while preserving full ATC visibility.
• ATC, TCAS, and traffic advisory systems are unaffected by PIA - the privacy benefit is specific to commercial and public aggregation, not safety surveillance.