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How Flight Tracking Works: a Global Network of Volunteers
An anonymous reader writes If a website can show the flight path and all those little yellow planes in real time, how can they not know where Malaysia Airlines flight MH370 went down? Answering that involves understanding a little about how flight-tracking sites work, where they get their data, and the limitations of existing technologies. It also involves appreciating a relatively new approach that the two large flight-tracking companies, Texas-based FlightAware and Sweden-based Flightradar24 are rushing to expand, a global sensor system known as ADS-B, which broadcasts updates of aircraft GPS data in real time. ADS-B is slowly superseding the ground-based radar systems that have been used for decades, becoming central not only to flight tracking but also to the future of flight safety. And it's powered, in part, by thousands of dedicated aviation hobbyists around the globe.
I live in the middle of nowhere in the USA, and provide ADS-B data. Its fun.
If you lived in a populated area like California or New York, there are already hundreds of people in your area doing this, and so its probably not necessary.
ADS-B is not powered (in whole or in part) by aviation hobbyists. They are just piggybacking with receivers for flight tracking.
The ADS-B system itself was designed for plane-to-plane communications to improve situational awareness. Ground-based ATC or hobbyists are not required to make the system work.
Source: I worked on an ADS-B product at Garmin.
It's a shame that services like FR24 are not more open. A lot of people are contributing to the service for free - though some may get a free subscription in exchange - but then what happens to that data?
First, it gets massaged. Sensitive flights, flights operated by people who don't want to appear on FR24, etc.get removed. Alright, I can see how that makes sense - if for no other reason than that if they didn't, they'd probably be shut down pretty quickly.
Second, you don't get access to the data. You only get access to exactly what they want to present - be that with ads around, under a subscription payment, or via apps, etc.
As an example, another app that gave superior AR results (point smartphone at sky, identify what plane is leaving what control) was shut down because FR24 didn't much appreciate them using the data off of the site - leaving users instead with the inferior FR24 AR.
However, the same applies to any other item. Would you like an alert whenever there's a rare plane passing over? Sorry - you can't do that. It would be easy to code, but you don't get access to the data.
Do you want to accumulate flight paths for an image of how flights appear around an airport? Easy to code, but no access to data.
See a flight that has no apparent destination, but you just know that if you look for similar flights along similar flight paths in the past, you could probably get a good idea of where it ought to be going - well unfortunately you can't do anything with that knowledge, because you get no access to data.
In more recent times, FR24's website has become less and less usable as things get tabletized - which you could fix by building a new site, but, of course, no access to data.
"Don't they have an API?"
No, they don't. The only API on their site is the string "API" in certain plane registrations.
Sure, you can access some of the data that's public by necessity of app limitations, but at the very top of the JSON output you'll find a message about how it's copyright and only for use by FR24 and if you use it for yourself they'll happily sue your ass, etc.
Of course, you could set up a rival website, but then you still need people feeding you the data - and it seems most of them are more than content with only feeding to FR24.
For something that is almost entirely dependent on semi-voluntarily provided information by the public, it's a shame that they cannot give back more to the public other than a premium subscription, and instead tries to monetize the data as much as they can; even their paid app ($3.50?) has in-app purchases for things like "Realistic aircraft symbols" - the same symbols that were available for free before... in the free app.
tl;dr: While sites like FR24 have popularized crowdsourcing of flight data, they have simultaneously crippled the potential of that data.
"ADS-B is slowly superseding the ground-based radar systems that have been used for decades"
... until the aircraft decides to become "uncooperative" and turns the darn thing off -- at which point, this (and any beacon/transponder-based system) becomes instantly useless.
Which is why you'll see ADS-B augment, but never completely replace old fashioned search radar anytime soon.
What you want is irrelevant; what you've chosen is at hand! - Spock, ST VI
You might be able to outrun the cop but you can not outrun his radio.
"So long and thanks for all the fish."
You're a retard. Really. Besides this is already being done on our roadways, with license plate readers...
You're a retard. Really.
Truly, certainly, actually indeed.
Besides this is already being done on our roadways, with license plate readers...
Using the fact that something has been done to justify doing it is genius.
from what I understand about Malaysia Airlines flight 370 is that the transponder stopped transmitting its position and heading to air traffic control before the plane entered Vietnamese airspace.
But the problem is the user application, at least for flightradar24. Have the paid version on iOS and it shows sometimes inconsistent data, or clearly not updated areas (while WIFI is ON and fast). If there is one tangible argument to show that the app is not well written: when the app is updating the screen (takes about .5~1 second for a busy area) the user cannot move (drag) the map (user should have priority as (s)he doesn't care about the display since it's gonna change in 2 seconds after moving!).
Slashdot, fix the reply notifications... You won't get away with it...
Absolutely. What are amateurs and meddlers doing with this information? Why they should have access to it? Is it even legal? Because it shouldn't be.
Dude, what is wrong with you?
No, seriously. There is really something very wrong with you. It sounds like a mental illness. You NEED to get it looked at by medical professionals.
Here in Europe radars remain essential because of Russian planes (both fighters and nuclear bombers) are flying around with their ADS-B switched of, just to test how quick European forces respond to possible treats. These planes fly in international air space, but often at close range of commercial flights. European countries are quite angry about this behavior, but the Russians think that they do nothing wrong. Just waiting for the first mid-air collision to happen. About a decade ago, the Russians started with these flights again, which they did during the Cold War. Especially, the last year they are become bolder and bolder, trying to enter national air space over and over again, and flying at supersonic speeds.
Classic Peg!
I am a blue water sailor. I, and many others like me, would be happy to carry an ADS-B reciever onboard. That is, provided that it draws very little power, and that it gathers data unattended without my active intervention. Statistically, I think cruising sailors would cover a large fraction of the ocean areas of the globe. I believe the probability of a sailing vessel being within 200 miles of MH370s final flight path would be almost 100%.
The caveat being that I can not transmit the data to the Internet until the next time I reach shore and I can find someone who will let me plug in a USB device. That could mean a delay of months up to a year.
Would non-real time information be valuable? Thinking of the MH370 case, the answer must be yes. Not matter what the delay, the information is still valuable to someone. We could also record AIS signals that many vessels already transmit. I receive AIS from up to 40 miles away.
The idea could be etended to (symbolic) notes-in-a-bottle. A million floating ADS-B recorders would eventually reach shore, and some of them may have their data extracted and transmitted, then thrown back into the sea. Would that be worthwhile? Hard to say.
The SKYWARN network that is involved with tracking storms, I was told, is also largelyl volunteer driven. It uses a network of amateur radio operators as storm spotters.
Most Respectfully Yours Mrs. Cleara Plastique
This seems a little misleading to me. ADS-B isn't required until 2020, and then only in those areas where radar transponders are required. You'd think this would allow flight without the radar treansponders, but alas, it seems they are still required.
No one, including the FAA, seems to know what they are actually doing.
I would really like to get my hands on a live ADS-B feed like FlightAware and FlightRadar24 apparently have. Does anyone know what I would need to do to do that? Global data would be ideal but European or Arctic coverage would also be very interesting. But others might be interested in other areas.
Posting to undo incorrect moderation (thank you, trigger-happy touchpad). Hopefully this still works as AC...
Because fucking big empty ocean, that's why. Cretins.
Dude, what is wrong with you?
No, seriously. There is really something very wrong with you. It sounds like a mental illness. You NEED to get it looked at by medical professionals.
What is wrong with the people who take information for purposes other than original intent without asking and proceeding to leverage it for commercial gain?
Did these companies ask the Pilots for permission first?