Of Planefinder sites, ground stations and radar ‘dead zones’

Planefinder provide flight information like GPS location + Direction + web lookup of flights

• Planefinder.net, Flightradar24.com, Radarvirtuel.com
• Aggregates data from all over the world
• User provided ground stations and data
• Generates near real time (-10 min delay) Google Map of air traffic
• Supports queries for Airlines, cities, tail numbers, flight
numbers, etc

Current Air Traffic Control
• Has not changed much since 1970’s
• Primary radar provides range and bearing, no elevation
• Transponder system (SSR) queries the plane, plane responds with a 4-digit identifier + elevation
• ID number attached to flight on radar scope, great deal of manual communication and work required
• Transponder ID used to communicate situations i.e. emergencies, hijacking, etc
• Transponder provides a higher power return than primary radar reflection, longer range
• Only interrogated every 6-12 seconds, low resolution of altitude
• Pilots get no benefit (traffic, etc)
• Requires large separation of planes (~80miles) which limits traffic throughput in busy areas
• IVR flights are way point based, not optimal or direct path
• Weather and other events (i.e. Volcano’s) can cause havoc around the world

Next gen Air Traffic Control
• Late 90’s FAA initiative to revamp the ATC system in the US, and via ICAO, the world
• ADS-B is the key feature, the datasource for “”Planefinder sites“”.

• Automatic Dependant Surveillance Broadcast
• Planes use GPS to determine their position, broadcast over 1 090Mhz (978Mhz for GA) at 1 Hz
• Contains Aircraft ID, altitude, position lat/lon, bearing, speed
• Recieved by a network of “”””ground stations“”””
• Particularly useful over “”””radar ‘dead zones’,“”” i.e. mountainous regions, “”””Oceans“””” (and where are you going to find those ground stations over the Oceans? Computer simulation, like GPS computer simulation?), Hudsons Bay, Gulf of Mexico, Alaskan mountains
• “””Certainty“”” of location allows for flights to “””be closer (5 miles)“””
• Two forms: ADS-B Out and ADS-B In

• No interrogation needed “””(Automatic) “””
• Instead of primary/secondary radar, planes report their location from GPS (Dependant) (And over the Ocean? Computer simulation?)
• Sent omni-directionally to ground stations and other aircraft (Broadcast)
• ATC’s scope is populated from received signals
• Uses1090Mhz for commercial (big stuff), 978Mhz for General aviation (small stuff)

• ADS-B IN: Optional (optional at the time of DEFCON 20) equipment can be installed in aircraft to listen to ADS-B out from planes and ATC
• Allows planes to be aware of each other without ATC intervention (TIS-B)
• Also allows for real time weather data (FIS-B)
• Situational awareness increases dramatically
• Also works for ground equipment and taxiing aircraft
• Expensive!! $5-1 OK for ADS-B out, $20K for ADS-B In
• GA market getting cheaper though

• ADS-B is unencrypted and unauthenticated
• Anyone can listen to 1090Mhz and decode the transmissions from aircraft in real time
• Simple Pulse Per Second modulated
• No data level authentication of data from aircraft, just simple checksums
• Some correlation of primary radar sighting to received data (changing to Multilateration,

• Others have begun to look and to question
• Righter Kunkel, Defcon 18
• Balint Seeber, spench.net – SDR research
• USAF Major Donald L. McCallie – Graduate research project
• Nick Foster – SDR and radio enthusiast
• UPS equipped all of their fleet

Presented at DEF CON 20 (2012), July 28, 2012, 5 p.m. (50 minutes)

Private aircraft provide transportation to:
corporate officers,
business owners,
high net-worth individuals, etc.

In recent years, sites like FlightAware

have made it trivial to access all public flight plans. However, aircraft owners can opt into a block list (the BARR) that prevents their flight information from being made public. All the interesting people are on the BARR. 2 Kids would try to explain the basics of how the the ATC system and sites like FlightAware work, in a clumsy attempt to demonstrate “””a serious method for tracking otherwise “untrackable”, BARRed aircrafts“””.

•    Semon Rezchikov – Independent Researcher
•    Dustin Hoffman – President & Senior Engineer, Exigent Systems Inc.

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