Curious- What is the orginal data source for your service? Is this data you (flightaware) pay for, or is the stream available from the FAA somehow?
Jason
Several different data sources are combined to provide this data; most of it originates at the FAA and FlightAware subscribes to a live data feed.
Great service! I work for Air Wisconsin up in KTVC. What data do you pull from the FAA and where is it located? I always wondered if there’s an online database of flightplans filed with Flight Service.
The primary data from the FAA is aircraft owner data, which doesn’t apply to most commercial flights. The only free, online database of flight plans filed in the US is FlightAware.
dbaker,
I just wanted to say thank you for this excellent service. As a student ATC’r at Miami Dade, as well as a continuing student pilot. . .this is one heck of a service. I also know it is becoming a huge hit within the flight simulator and real-online ATC services such as VATSIM and VATUSA as they are now able to get real, honest to god, flight plan data for routes from anywhere within the US.
Great job! Keep up the great work, and if a donation is needed, or is wanted, let me know. I’d be more than happy to give you a little something in return for this wonderful gift to all of us!
-Josh
On a random note I think I might have an idea as to how the pay services get their data. I think they actually use ACARS, and have recieving stations around the country all networked in. That being said, I could be horribly wrong. Maybe someone has an idea?
I believe Passur uses such recieving stations for ACARS data, but most tracking sites do not.
The pay tracking sites all subscribe to the same data as FlightAware, yet are inherently committed to their antiquated business models.
As far as Passur (which I believe is free to end-users), my understand is that their receiving equipment at airports receives radar and position information but not ACARS although I’m not certain.
From the Passur users manual:
"PASSUR stands for Passive Surveillance Radar.
The Passur system allows one to view actual airborne traffic around selected locations in real time. The Passur does this by passively eavesdropping on FAA secondary radar transmissions ( also known as interrogations), which send discrete signals to an aircraft, and the aircraft’s transponder transmissions ( the aircraft’s replies to the radar’s interrogations). The Passur system does not transmit any signals of its own- it just listens.
Using Megadata’s patented Pastrack sofware system, the Passur system is able to track in excess of 350 aircraft simultaneously and display their actual location in real time. Passur provides aircraft identity, position and groundspeed, and automatically calculates Estimated Times of Arrival ( ETA’s) for aircraft inbound to the selected airport. The Pastrack software system is designed to learn the normal approach sequences most often assigned by ATC, which allows the system to become ever more accurate with time.
The Passur system will allow an airline to predict with high levels of accuracy the estimated arrival times of aircraft. even if the flight crew’s are in a sterile cockpit environment for extended lengths of time. These reliable ETA’s allow for more efficient utilization of ground personnel and gate agents and enhance pre-planning for connecting flights.
The Passur system is a UNIX based program, which utilizes a windows-styled presentation for ease of use. Most functionalities will be familiar to those already acquainted with windows-styled word processing applications."
I hope this explains a little bit about how the Passur works!
And this:
“As far as Passur (which I believe is free to end-users), my understand is that their receiving equipment at airports receives radar and position information but not ACARS although I’m not certain.”
You were right on about the airport radar, but wrong about the FREE part! I know my company pays a pretty penny for the service!
This site, however, enables me to look up and track any flight I want at any time, without having to mess with our settings on the Passur. I like this site because I can use it at home, and it actually offers many things that Passur doesn’t. I look forward to the day when we can use filters on the maps here, and when the time delay becomes less. I’m a huge fan of flightaware, and have been spreading the news!
Cheers
Chuck
Thanks for the Passur background info. I should have clarified that by ‘end users’ I meant folks looking for plane tracking stuff on the web since it’s also free at various airports to a casual observer, although their web software has never worked for me. 
I’ve tried 4 or 5 times and it just loads the maps and no planes. Needless to say, I haven’t been all that impressed.
Huh…I have no idea how their freeware works, but the paid system is indeed impressive. But have no fear…you guys are catching up fast!
Yes, the data obviously comes from the same place as the other tracking sites, which is presumably the FAA ASDI data feed. What is interesting is that there is a cost involved in obtaining this data, such as dedicated T-1 lines (not cheap), and other costs (servers etc.) which is why most charge at least 15-20 bucks a month.
Interesting that you can do this for free … and a nice job too!
Who’s paying the bills … or are you stealing the data ? 
Great Job,
Jimbo
Hi, Jimbo.
As I said, the pay tracking sites are all are inherently committed to their antiquated business models. FlightAware’s next-generation software with a next-generation business model (that includes offering it free to consumers) is an obvious win.
Daniel
Right, but presumably the object of any ‘business model’ is to make a profit … one way or another … be it subscriptions, advertising, etc. etc.
Don’t get me wrong … the system is absolutely great. Just a curious mind, that’s all
Jimbo
I understand your interest and appreciate it although we’re not interested in talking about the model just yet. Of course, that will change and it will become more and more transparent over time.
I found this. Some of you might be interested.
The number of flights looked low to me, so I dug into the data issues a bit and found the following info about how data gets into the data feed (thanks for the ASDI pointer, jgillman!):
What do we GA pilots have to do to actually appear on the Flight
Explorer display? Do we have to activate a flight plan, does it have
to be IFR, do we appear if we’re just having simple flight following?
As near as we can determine, whether or not an aircraft appears in the
FAA’s ASDI feed (and therefore shows up on the Flight Explorer
display) depends on whether that aircraft has a flight plan in one of
the ARTCC computers. All IFR aircraft do, of course. Most VFR flight
following aircraft do not, because controllers typically enter only an
“abbreviated flight plan” for an aircraft who requests VFR flight
following, and that’s not sufficient to get the target into the ASDI
feed. On the other hand, an IFR aircraft who cancels IFR and asks for
VFR flight following will typically remain tracked on the ASDI feed
because his flight plan is already in the ARTCC computer.
Filing a VFR flight plan won’t do it, because those flight plans
typically remain at the AFSS where filed (or in the DUATS system if
filed that way), and are never sent to the ARTCC.
We’re continuing to research this question and will add any new info
we receive to this page.