Not quite all aircraft are required to have ADS-B in all situations, there are a number of edge cases out there. But close enough, I suppose, and most planes people would want to track are required to have it.

However, there's also a new privacy initiative that allows aircraft to fly under temporary ids. The FAA will still know who they are, but for 3rd parties it will become much more difficult to determine.

https://www.aopa.org/news-and-media/all-news/2019/december/2...

Also, the US allows using UAT on 978 MHz for ADS-B requirement for planes below 18,000 ft.

Most SDRs only decode 1090 MHz signal. It is possible to decode 978 MHz but requires more work to support both.

I know what you mean, you mean the software for SDRs is mostly geared towards tuning to 1090 MHz and decoding ADS-B pulses there.

But to be clear: the SDR's tuners are rarely limited that way. Most can tune to 978 MHz even easier than 1090 MHz. Covering the entire VHF to UHF range is pretty typical.

When I've set up P25 receivers, it's common to use 2-4 RTL-SDR's to do the bulk of listening. Each rtl-sdr gets set with a different center freq, and the control channel tells when and where to listen.

You can build a P25 listener for less than $100.

which software do you use to demodulate P25? gnuradio?

I use https://github.com/robotastic/trunk-recorder

You'll use https://www.radioreference.com and get the appropriate control and voice channels for your area. You'll also get the talkgroups and put them in a CSV.

From there, you'll use http://garvas.org/trunk-recorder/ to determine how many RTL-SDR dongles (or others) you'll need, along with their respective center frequencies. Note that you'll copy/paste the relevant control/voice line for your p25 from radioreferece.com

From there, just define where to store the files on the drive, and off it goes. There's a python webserver ( https://github.com/ScanOC/trunk-player ) you can install for on-prem, and/or you can also upload it to openmhz website ( https://github.com/robotastic/trunk-recorder/wiki/Uploading-... ).

Not OP, but thank you! I recently got a SDR dongle and was going to set it up. This will help.

Not difficult at all:

https://www.adsbexchange.com/how-to-feed/adding-978-mhz-ads-...

Good points all around. I figured the exceptions were esoteric enough to not bother with immediately but are very valid.

I'm interested in seeing where the proposal goes. I'm not sure where I stand on the issue but I'm curious of others opinions.

I hope not. Unlike car license plates, if you own a plane what you're doing with it is very much in the publics interest to know, especially if you don't want people to know.

They can have their privacy while they aren't flying polluting multi-million dollar planes through the country and above our buildings.

First, airplanes come in a lot of different sizes, and many don't cost anywhere near millions. A quick search online shows that you can find a used Cessna 172 starting at $35k - and is about the same size as a car.

Second, just because an airplane is over your building, doesn't mean it's going to crash into it. Even in an emergency, airplanes can keep gliding. A car is more likely to hit you while you're on the sidewalk - does that mean you get to know the name and address of every person driving local streets?

Third, I don't see how pollution has anything to do with privacy.

I can see an argument for being able to report an airplane doing something unsafe. But that's literally what the FAA exists for, and they have ways to look up who's flying an aircraft — anonymous or not. I don't see a good argument to releasing owners' names and addresses publicly so people can do law enforcement themselves.

I brought up pollution to point out that, although certainly worth it, society is paying a pricy to let people fly aeroplanes around as they wish. Since people owning planes are not just regular citizens, society should hence have some level of visibility into what people are doing with them.

Similar things apply to e.g. Amateur Radio. We've given people a big chunk of spectrum, and in exchange we expect transparency on what it's being used for. With few planes being owned by individuals, the case should be even stronger for aeroplanes, since the privacy argument applies less.

Personally, requiring a public address for amateur radio is a big problem and I'd argue needs to be changed.

It makes you a target for doxing and swatting, and causes an unending amount of spam mail that you can't unsubscribe from.

It made sense in the older days when people routinely mailed paper QSL cards. The FCC also relies on amateur radio operators to self-police each other, which is relatively unique as far as enforcement goes (see: ARRL official observers - but even in that case, if you do something sufficiently wrong then the FCC will get involved and could look up your address).

On the other hand... QSL cards are pretty cool.

In the US the address you give the FCC when you apply for a ham license does not have to be the address of where you live. It just has to be an address where you receive mail. I used my PO box.

When I found out Tim Allen has a ham license, I looked up his callsign record. He uses his production company's address.

There was actually a situation where a person who was feeding the ADS-B Exchange network used their amateur radio callsign as their station ID, and another feeder looked up their info and called them to complain that their raspberry pi's clock was out of sync and screwing up the network.

> does that mean you get to know the name and address of every person driving local streets

That might be a thing when self driving cars proliferate.

You can register an aircraft to an LLC / company. Doesn't always have to be registered to a person.

Private Crop dusting pilots flying over cornfields in southern Nebraska aren’t flying over your buildings mate.

Well put.

I also don't want my location broadcast as I move around on foot, or in my car, so why would I want to be tracked in the air?

And if you don't like being tracked, what makes you think that others want to be tracked all the time?

Do you own an personal aeroplane with ads-b transmitter? Do you think it's likely you're going to own one anytime soon?

This isn't the private data of your neighbor. This is either data from corporations which, despite being people in some senses, don't have any privacy rights, or individuals so rich that what they're doing with planes that they really want to keep secret should be everyone's concern.

I think you misunderstand how much planes cost. Many GA pilots aren’t rich. You can by a Cessna 150 for $16k as an example:

https://www.trade-a-plane.com/search?category_level1=Single+...

The pilot of this is likely not some rich individual undergoing clandestine operations.

... I know of several people nearby (relatively speaking, same metropolitan-ish area) with pretty middle-class salaries and jobs who own airplanes- not jets or anything, just smaller prop planes (like itty bitty Cessna things) and a couple people with ultralights they can land in their (fairly spacious) backyards.

Meh? As a passenger, I don't want to be tracked the way we do cattle.

Maybe I'm missing the point here, but more tracking feels more invasive and more likely to lead to abuse of said information (information imbalances equate to power, too!) and I don't want any more of that than is absolutely positively unavoidable.

> or individuals so rich that what they're doing with planes that they really want to keep secret should be everyone's concern.

You know a used Cessna is within the range of a new car, right? Is anyone who owns a townhome also in your "so rich they can't have privacy" category, because the cheapest junky townhouse around me is easily 6x the cost of a cheap personal aircraft.

Um, Yes. How do you know I’m not your neighbor? I’m middle class in the tech world and built an airplane. It cost less than a lot of luxury cars probably parked outside your workplace.

There are 600,000 GA pilots in the US. It’s ignorant if you think we all have Gulfstreams.

> How do you know I’m not your neighbor? I’m middle class in the tech world and built an airplane.

My dad was a pilot and engineer, and we built many things together in my childhood (go-carts, computer video games, an automotive speedometer, more).

But there was one thing that I always wanted to do with him: build an airplane. As a 13 year old, I found different plans from vendors, created a budget, put together a basic timeline, but could never convince him to do it.

In fairness, building a plane is a huge multi-year commitment, and almost certainly more expensive than buying a used Cessna. But the price is not completely out of reach for many folks (<$100k). The real draw is the amount you learn during the process and seeing your handiwork.

I'm still sad we never did it, but it was a big ask of a dad with a full-time job from a twerp son. As a consolation however, he did buy a small wing-section kit and we got to rivet a few panels together over a weekend. First time I ever used rivet fasteners!

What did you build? Working on an RV8 myself.

8A, of course my dad helped

I think this kind of comment (“it doesn’t affect you personally, so why do you care at all?”) suggests a shocking lack of empathy.

Flying also isn’t a prohibitively expensive activity; I know high school teachers who fly small aircraft.

I think you have an incorrect understanding of who owns planes. You'd be surprised how many of your neighbors own or rent aircraft at your local GA airport.

It's not just something multi-millionaires do. In many cases it's cheaper than owning a Tesla.

Heck, one can buy a sport plane[0] for less than the MSRP of a brand new Honda.

[0] http://www.zenithair.com/zodiac/ch650/650-price.html

A sport plane sans engine. An aircraft engine is like $30,000.

Private Crop dusing pilots aren't trying to hide themselves from the airplane maps, so this is irrelevant to the point.

I'd say they're more likely to be hiding themselves from the map than your average commercial flight.

Pilots of small aircraft are just as sensitive about giving up their privacy as anyone else.

Would you want your name, address, and position broadcast on the internet every time you get in your car?

Not just sensitive about their privacy, but there is a particularly ornery set of opinions among rural pilots regarding the government “telling me how to tend my own farm” which I think is at the root of what we see at the surface as being “privacy concerns”.

So when someone says these types of aviators aren’t trying to hide themselves I’m highly skeptical on just how well-versed the speaker is with the issues and perspectives this class people have with more and more expensive operating requirements being put on them with diminishing returns for their compliance.

Then again, this perspective isn't in line with "rich moguls and their private personal jets" and represents a blue-collar voice that gets left out of discussions in this community with a frustrating frequency; so I'm really not surprised, either.

Hell go talk to some ground-based truckers how they feel about having their routes tracked by logistics companies who book them for loads. There’s videos all over YouTube from long haul truckers complaining about faceless entities demanding they install tracking systems or download GPS enabled apps and the constant complaint is “don’t tell me how to drive my truck"

These operators want autonomy.

I would beg to differ and could probably accurately guess that several ag pilots I know would as well.

You can track my plane when I can track your car. Both are capable of nefarious deeds -- as is a bicycle, backpack, or hoodie.

The only thing special about private aircraft is people picturing some high-dollar gulfstream, and aiming a bit of jealousy at the people who own and operate them. Some of us fly planes that cost less than your Tesla and would prefer not to be painted with that broad of a brush.

I mean, barring legal limitations I'm unaware of, you're surely free to set up your own ALPR ("automatic license-plate reader"), set it up aimed out your window/balcony and collate the data with other fellow ALPR-constructing individuals on a website like the OP.

Certainly. And I doubt I would annoy many people due to locality, odds of them simply not driving past the thing, and of course, only a few people knowing I'm doing plate scanning and posting it online.

This is a government program, mandate even, with easily-downloaded data feeds.

My 'you can track my plane when...' was hyperbole for the moment. ADS-B compliance cost me a few thousand dollars. Getting off of the public 'radar' with my plane is on my 'get to it eventually' list of things to do. Somewhere around refinishing my deck and swapping my winter tires back for all-season. I'm bothered philosophically, but my actions say I'm not that bothered.

But to your point, if the government required all car owners to pop a GPS tag onto their honda, at a cost to them of a few hundred bucks, then gave the 24/7 surveillance data to the public freely, I can see a few noses being tweaked for a few different reasons.

Edit -- I guess this thread is getting too deep for more replies. Aircraft have registration numbers painted on their side. That's the analogy to license plates which are publicly visible, and systems do exist to video-capture those numbers (usually for billing purposes -- Vector is one I know of). ADS-B is automatic reporting/broadcasting by the aircraft itself. It is collected and distributed by government, and it is also capture-able by anyone with a receiver. I am not aware of any cars which broadcast their movements 24/7 to government, nor any initiative to make that happen at car-owner expense, nor the ability for one to capture that data freely on radio bands.

But I think the 'of interest to society' argument against cars is equally strong. Which was the original idea I was replying to. :)

> This is a government program, mandate even, with easily-downloaded data feeds.

Hang on. The ADS-B requirement is a government program, like car license plates. The data feeds are privately collected, and similar things absolutely exist for cars.

https://www.vice.com/en_us/article/ne879z/i-tracked-someone-...

> DRN is a private surveillance system crowdsourced by hundreds of repo men who have installed cameras that passively scan, capture, and upload the license plates of every car they drive by to DRN's database. DRN stretches coast to coast and is available to private individuals and companies focused on tracking and locating people or vehicles.

Why do you need to know exactly who is in a plane? How does that help you at all? What do you do with this information to improve your life?

This data directly led to the discovery of a large scale, secret aerial surveillance program by the FBI, which led to Congress demanding information about the legal and privacy issues: https://www.theatlantic.com/politics/archive/2015/06/congres...

> Most networks like Flight Aware allow owners to blacklist aircraft such that their tracks do not appear on the site.

Do you know more about how this is done? Is there a fixed price list for this service? Can one "buy" it online? Is there some sort of registry that is shared between networks?

> Additionally military aircraft are typically not reported.

While I'm sure the military can turn off transponders at will, I presume (?) they often fly with them on. Can these signals be tracked with "standard" gear when they are on?

The FAA runs the blocking programs, there's no fee https://www.fly.faa.gov/ASDI/asdi.html https://ladd.faa.gov/

A copy of the ASDI block list is on https://www.muckrock.com/foi/united-states-of-america-10/faa...

The FAA also has a new program to hand out pseudonymous aircraft identifiers via commercial providers so there probably is a fee for that https://www.faa.gov/nextgen/equipadsb/privacy/

FlightAware sells blocking services and dashboards. Don't be fooled, the privacy lobbying is only to make more money for FlightAware and FlightRada24.

Feeders sending them free data for fake enterprise dashboards and fake "$89 value" accounts have made David Baker a multi-millionaire.

*Daniel Baker

I've heard that the first few years of flightaware they made most of their money in taking requests for not publishing specific aircraft.

As for military stuff - they have additional capabilities for their transponders that provide for responding to interrogators (think identify friend or foe - IFF systems). They're not supposed to disable transponders in the required airspace - they've got to comply with the FAA rules too. There are situations where ATC transfers control over to the military where they are free to do more things. Like in a hot military operating area (MOA) or when ATC transfers traffic separation to the military (MARSA).

I wonder whether those hedge fund people have smartphones and if they do whether they choose Apple, Android or do not care. That would be pretty valuable information in the wrong hands, all it takes is one silly game with a permission too many and your goose is cooked.

On apple at least there's a lot of repeat asks these days. It doesn't just ask "can X use location data", it asks you a day later "hey X has been using location data while in the background do you still want to allow this". Then again more days later, and again.

On iOS at least I think this door is closing.

I think you’re misunderstanding. Hedge fund people want the locations of CEOs, CFOs, mergers and acquisitions lawyers, etc because they can infer a lot about potential deals (or issues). Nobody usually cares where the hedge fund analysts themselves are.

I don't believe private owners are the most interesting black-listed things. Military aircraft anyone? Who doesn't want to see those :)

I noticed a helo circling with a huuge spotlight a mile or so from my house, and the skies were empty according to flightradar24, but ads-b exchange showd me that it was a police helicopter. I can see the reason for blacklisting those, so the people being chased cant easily track the helicopter? Otoh theyre bloody obvious due to their noisiness imo so I dont think it would matter one bit for the 1% of criminals aware enough to use flightradar24 to somehow evade capture..

This will be an interesting wrinkle for US college athletics. Coaches defecting to another university after secret negotiations has become very common. Watching the flights of university owned aircraft and those of prominent boosters has become a way of detecting that such negotiations might be taking place. While public universities would have a difficult time justifying paying to hide their flight data, private universities and boosters have both the means and motive to do so. A source like ADS-B Exchange neutralizes this tactic.

I wonder if any of the security threats brought up in https://www.youtube.com/watch?v=CXv1j3GbgLk has been addressed. (Fun demo at 42:00)

Correction Context: As of the beginning of 2020 all aircraft in the United States are required to have ADS-B out capability.

This is not true. ADS-B OUT is required to fly in certain classes of airspace, above 10,000 feet, etc. -- anywhere a transponder is currently required. That's all.

That leaves a lot of airspace in the US. Someone flying his C182 in eastern Wyoming may not bother with it as he does not see any benefit. Here in western Oregon, I see the benefit (weather and traffic via ADS-B IN) and have equipped my aircraft even though I (mostly) avoid the airspace where it is required.

Thanks for the info. I had read it was becoming mandatory in the US in 2020. That was in the context of Australian regulations where aircraft still aren't forced to have ADS-B.

some exceptions: As such, we have concluded that the same aircraft excluded from the transponder requirement are excluded from the ADS-B Out equipage. Accordingly, an aircraft that subsequently has been installed with batteries or an electric starter would not be required to equip for ADS-B Out. The FAA may consider a technical amendment in the future to remove any confusion due to the discrepancy between the language in§ 91.215(a)(5) and§ 91.225(e).

https://www.faa.gov/about/office_org/headquarters_offices/ag...

see also

https://www.aopa.org/news-and-media/all-news/2017/january/19...