Feedback on ADS-B tower locations

What I would like to do is to map them, both on the sectional charts and on my ForeFlight. I am at the 75+% point having accomplished the later. I use them to plan flights and in some cases choose where I land. I eventually plan on being able to determine which stations are working and providing services and report outages.


Be interesting to see your final product. I often wondered about their placement. Were they placed based on where they should go to provide the best coverage or where they could negotiate placement (cell phone towers)?
 
This is precisely the data I've been looking for -- thanks.

The only thing missing? Whether individual towers are "up" or "down". Down on the coast towers appear to go "down" for varying periods of time, without explanation or warning, which makes troubleshooting an installation difficult. ATC doesn't know or care.
 
This is precisely the data I've been looking for -- thanks.

The only thing missing? Whether individual towers are "up" or "down". Down on the coast towers appear to go "down" for varying periods of time, without explanation or warning, which makes troubleshooting an installation difficult. ATC doesn't know or care.

I have raised this as an issue at ATPAC that there is no way to report issues with towers.

As far as troubleshooting an installation, there are tools available. With the ForeFlight/Stratus combination, you can use its own ship feature and decode everything being broadcast by your aircraft ADS-B Out and can determine if it is installed and configured properly. The FAA also has a free compliance service that you can use to get a report on your system via email. The FAA says about 80% of the installations are not compliant for one reason or another. My GDL88 shows as being compliant on both ForeFlight and the FAA report I had requested.
 
Be interesting to see your final product. I often wondered about their placement. Were they placed based on where they should go to provide the best coverage or where they could negotiate placement (cell phone towers)?

Most are on existing cell towers. You can use the file I provide with Google earth and zoom in to see the tower. Some of the ones located at airports are on a barber pole tower. The contract specifies service volumes that must be covered and as long as the coverage from the towers provides that, the FAA is happy. Each of the vendors that submitted bids had a cell tower partner. If I recall corectly, AT&T was the partner of the winning bidder.
 
I have raised this as an issue at ATPAC that there is no way to report issues with towers.

As far as troubleshooting an installation, there are tools available. With the ForeFlight/Stratus combination, you can use its own ship feature and decode everything being broadcast by your aircraft ADS-B Out and can determine if it is installed and configured properly. The FAA also has a free compliance service that you can use to get a report on your system via email. The FAA says about 80% of the installations are not compliant for one reason or another. My GDL88 shows as being compliant on both ForeFlight and the FAA report I had requested.
Yeah, I know about that. I have been using the Nexus 7/GDL-39 combo in a similar fashion, and have requested and received the FAA's printed report on how my in-panel installation looks to them.

It failed, of course, because I'm using a non-certified GPS as my location source. But otherwise it was working fine.

But this still doesn't help with determining ADS-B functionality on the fly. When I'm flying along, and my traffic disappears, I have no way of knowing if it's a problem with the ground station, or a problem with my installation. No one knows the status of those ground stations, and worse -- no one cares. Yet.

I suspect this will improve as we get closer to 2020.
 
I suspect this will improve as we get closer to 2020.


You probably suspect wrong. If the engineering didn't include how the system's fail safes and outages are handled, it'll take more money than God has to engineer it in later.
 
You probably suspect wrong. If the engineering didn't include how the system's fail safes and outages are handled, it'll take more money than God has to engineer it in later.

I am fairly confident that the system will detect and report most problems, but the pilot is not likely to be aware of the outage or how they are affected. The broadcast data has some capabilities but I am not confident that this is being taken advantage of, in particular, by non certified equipment.
 
I am fairly confident that the system will detect and report most problems, but the pilot is not likely to be aware of the outage or how they are affected. The broadcast data has some capabilities but I am not confident that this is being taken advantage of, in particular, by non certified equipment.


That's not a complete SYSTEM then. Engineering fail.
 
The lack of completeness is in the airborne or portable equipment, the data is there.


Huh. I heard there was this thing called a certification process for those... A really expensive to maintain taxpayer thing run by all the best experts. :)
 
Portable equipment is not certified.


You included "airborne" and at least one poster has the exact problem you're defending in an aircraft installation. Are you claiming the certified gear has the warning requirement or just making excuses for the total crap engineering of the entire project?
 
You included "airborne" and at least one poster has the exact problem you're defending in an aircraft installation. Are you claiming the certified gear has the warning requirement or just making excuses for the total crap engineering of the entire project?

Thanks for your contribution.:rolleyes2:
 
Example: I just landed. When we departed, I instantly showed traffic at my altitude, just a few miles North, headed at me.

We found the targets -- two Skyhawks (!) that had just departed, flying very close formation at about 500 feet AGL. They were on the North side of the channel, over uninhabited St. Joseph ' s Island, so I guess they were legal.

I had them on my GRT Horizon EFIS, and Mary had them on the Nexus 7/GDL-39 in the back hole.

Anyway, we flew around a bit, then turned back to land. We heard these guys coming into land (flying opposing Left-hand AND right-hand traffic), but they never appeared again on ADS-B.

Why? Did the ground station fail? Surely both of our receivers didn't simultaneously fail? Did they both turn off their transponders?

It would be nice to know. Currently, there is simply no way to troubleshoot such a signal loss.
 
The problem is, it depends. There are numerous reasons why you may not have seen them. To see ADS-B traffic, one of the following is needed:

1) The target has mode-s 1090ES, and you can receive and display Mode S 1090ES air-to-air.

2) The target has a UAT, and you can receive and display UAT air-to-air.

3) You or someone near you has ADS-B out, which activates TIS-B, and you see the target as picked up by approach/center radar if you can receive and display TIS-B.

Since nothing indicates how a particular target is being received on your display, and nothing indicates if the ground based system is working, the answer is who knows.

I think #3 is most likely and they were simply below radar.
 
Example: I just landed. When we departed, I instantly showed traffic at my altitude, just a few miles North, headed at me.

We found the targets -- two Skyhawks (!) that had just departed, flying very close formation at about 500 feet AGL. They were on the North side of the channel, over uninhabited St. Joseph ' s Island, so I guess they were legal.

I had them on my GRT Horizon EFIS, and Mary had them on the Nexus 7/GDL-39 in the back hole.

Anyway, we flew around a bit, then turned back to land. We heard these guys coming into land (flying opposing Left-hand AND right-hand traffic), but they never appeared again on ADS-B.

Why? Did the ground station fail? Surely both of our receivers didn't simultaneously fail? Did they both turn off their transponders?

It would be nice to know. Currently, there is simply no way to troubleshoot such a signal loss.

Do you have ADDS-out? I'm just starting to learn about this, but my understanding is that you can get ADDS-in without having ADDS-out. But only if another aircraft nearby is transmitting ADDS-out. They are one that is triggering the ADDS-in that you can see. If they move out of area of your receiver, they won't trigger the ADDS-in that you were seeing.

The upshot is that ADDS-in is unreliable if you don't have ADDS-out.

Sorry if this has already been covered. As I mentioned, I'm still struggling to understand.
 
Do you have ADDS-out? I'm just starting to learn about this, but my understanding is that you can get ADDS-in without having ADDS-out. But only if another aircraft nearby is transmitting ADDS-out. They are one that is triggering the ADDS-in that you can see. If they move out of area of your receiver, they won't trigger the ADDS-in that you were seeing.

The upshot is that ADDS-in is unreliable if you don't have ADDS-out.

Sorry if this has already been covered. As I mentioned, I'm still struggling to understand.
Yes, we have ADS-B in and out.
 
The problem is, it depends. There are numerous reasons why you may not have seen them. To see ADS-B traffic, one of the following is needed:

1) The target has mode-s 1090ES, and you can receive and display Mode S 1090ES air-to-air.

2) The target has a UAT, and you can receive and display UAT air-to-air.

3) You or someone near you has ADS-B out, which activates TIS-B, and you see the target as picked up by approach/center radar if you can receive and display TIS-B.

Since nothing indicates how a particular target is being received on your display, and nothing indicates if the ground based system is working, the answer is who knows.

I think #3 is most likely and they were simply below radar.
We often see traffic targets on the ground.
 
We often see traffic targets on the ground.

Do you mean that you are seeing targets that are on the ground, such as taxiing aircraft? The only way you're going to see ground traffic on ADS-B is if you're receiving it directly air-to-air. Your aircraft's ADS-B IN is directly receiving the ADS-B OUT transmission from the other aircraft on the ground. Not via TIS-B through the ground towers. I find it highly unlikely that approach radar is picking up ground traffic at this airport for you to see on TIS-B from the ground towers. Which for the same reason, could be why you didn't see those low level aircraft, since they too are below approach radar.

Which is also why you would only see some, not all ground traffic, since you can only see aircraft that are also equipped with ADS-B out for air-to-air.

Of course, this is all a guess since there is no way for anyone on either end to know anything about any of the information they are receiving and/or not receiving at any time....
 
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Another example from today:

Took off from KRAS (on the coast near Corpus Christi), and had traffic and weather immediately.

Flew inland an hour to Cotulla, KCOT. Enroute, maybe 30 miles inland, traffic disappeared, followed a short time later by weather. I never saw it again, until...

On the return flight, I had nothing on my EFIS until we were about 50 miles out. First radar came back, followed by traffic.

Interestingly, we retained both traffic and weather longer on the Nexus 7/GDL-39 combo on the flight out, but the EFIS got it back sooner on the return flight.

Radar updates are different between the two systems as well. Sometimes the EFIS radar is newer, sometimes the tablet's radar is newer.

ADS-B is a very complex system. I wish it were simpler, and easier to troubleshoot.

BTW: I spoke with a LockMart briefer today who had no idea if he was going to end up with responsibility for ADS-B coverage NOTAMs, as previously reported. He certainly had no knowledge of the current system's status.
 
BTW: We saw ground targets again at KRAS today. They had the prop turning, and were nearly ready to depart as we entered the downwind.
 
I think you're very accurately demonstrating that there is no way to know if and/or why you are and/or are not receiving something, anything, or nothing. I hope that by 2020, they've rectified that.

Again, the only way you're going to see ground traffic on ADS-B IN is if you're receiving it direct air-to-air from an ADS-B out equipped aircraft, or the airport surface is covered by and not filtered out of approach radar which puts it on TIS-B.
 
I think you're very accurately demonstrating that there is no way to know if and/or why you are and/or are not receiving something, anything, or nothing. I hope that by 2020, they've rectified that.

Again, the only way you're going to see ground traffic on ADS-B IN is if you're receiving it direct air-to-air from an ADS-B out equipped aircraft, or the airport surface is covered by and not filtered out of approach radar which puts it on TIS-B.
The skydiving jump plane we saw on the ground while we were airborne doesn't have ADS-B out, in, or otherwise.
 
Do you have a TCAS? There are only two ways a non ADS-B aircraft can be a target on your screen:

1) You have a TCAS, which has nothing to do with ADS-B and will show anything with a working mode C Transponder

2) It is being picked up by ATC radar, and pushed out to your though TIS-B.

Presuming the latter, that would mean their radar works to the ground and is being piped to you on TIS-B.
 
The last jump plane I saw has more duct tape than rivets. Let alone a $5000 ADS-B out. Lol
 
For $2B and counting, the questions shouldn't even be necessary.

Why are you attacking the OP over something he has no control? He just wants to get info on ADS-B tower locations. He answered a few of your questions as best he could. He's not a government shill just because he can't or wont address your criticisms of ADS-B.

I don't like ADS-B from a technical standpoint, or the mandate either, but approve of the OP's endeavor.
 
Why are you attacking the OP over something he has no control? He just wants to get info on ADS-B tower locations. He answered a few of your questions as best he could. He's not a government shill just because he can't or wont address your criticisms of ADS-B.

I don't like ADS-B from a technical standpoint, or the mandate either, but approve of the OP's endeavor.


I'm on his side on the silliness of the locations being a "big secret". Anyone actually intending to harm a site (you know - the terrorists! Gasp!) could DF it in about an hour, less if Doppler gear is used.

He'll put in a bunch of work showing where the stuff is and that'll lead to some bureaucratic moron deciding there's no point in hiding it anymore.

Works for me.

He decided to get personally snippy. I didn't start that.
 
He decided to get personally snippy. I didn't start that.

Nate, to my eye it started getting snippy right here:

Are you claiming the certified gear has the warning requirement or just making excuses for the total crap engineering of the entire project?

So why don't we all take a deep breath and start playing nice again?
 
Nate, to my eye it started getting snippy right here:



So why don't we all take a deep breath and start playing nice again?



Cool. I'll start!

"The ADS-B system sucks."

There. All better. :lol:

Seriously, I am growing frustrated with it. I spent the money, bought the In/Out avionics, understand how the system works, also understand that the system will only improve over time -- but I want the ability to troubleshoot it!

Right now, as we sit here typing, ATC knows nothing about it. Flight Service knows nothing about it. There is so far ONE GUY (over on the Van's Air Force site) who claims to work for the FAA who has been helpful in obtaining validity reports from the FAA -- but there seems to be absolutely no real-time reporting of outages.

Or "inages" (is that the opposite of an "outage"?), for that matter.

We simply have NO IDEA, on a day to day basis, what parts of the system are working, and what parts are not.

I presume SOMEONE inside the FAA knows, but they ain't sharing. We need to find out how to fix that.
 
Cool. I'll start!

"The ADS-B system sucks."

There. All better. :lol:

Seriously, I am growing frustrated with it. I spent the money, bought the In/Out avionics, understand how the system works, also understand that the system will only improve over time -- but I want the ability to troubleshoot it!

Right now, as we sit here typing, ATC knows nothing about it. Flight Service knows nothing about it. There is so far ONE GUY (over on the Van's Air Force site) who claims to work for the FAA who has been helpful in obtaining validity reports from the FAA -- but there seems to be absolutely no real-time reporting of outages.

Or "inages" (is that the opposite of an "outage"?), for that matter.

We simply have NO IDEA, on a day to day basis, what parts of the system are working, and what parts are not.

I presume SOMEONE inside the FAA knows, but they ain't sharing. We need to find out how to fix that.

I agree.

I have attempted to do something about it. I have raised the issue at ATPAC that there is no means available today to report issues on the ADS-B system today. I argued that now is the time to sort out issues and resolve them. I pointed out that I followed the guidance in the current NOTAM system and contacted FSS with a problem to report. They had no clue. I escalated to management and they finally got back to me and indicated that despite what the NOTAM says, they have no guidance from the FAA on how to deal with any outages or ADS-B issues.

ATPAC members agreed and they accepted my issue as an open area of concern (AOC).

ATPAC is a committee that brings controllers, pilots, and the FAA together to discuss issues that affect all of us in the system. I am not a member, but it is an open meeting to the public and I attend at my own expense. This committee investigates and makes recommendations to the FAA to resolve these kind of issues. It reports its findings directly to the Administrator.

If you are interested, you can read the minutes of the last or any meeting by going to https://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/systemops/atpac/

The minutes of meeting 148 contain the issue I raised.

Although I enjoy participating in these forums, I am not the type of person who is simply willing to just talk about it. I try to and do something about it. I tried to go thru the Alphabet Soup organizations to raise these kinds of issues, but they don't have the experience or skills to understand and contribute on our behalf. So out of frustration, I joined the groups as a member of the public.


I also participate in ACF/IPG meetings and have been able to have a significant impact in getting some issues addressed that need to be addressed. ACF can be found at http://www.faa.gov/air_traffic/flight_info/aeronav/acf/ smf IPG can be found at http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afs/afs400/afs420/acfipg/
 
John, thank you for your efforts on this issue. And for your submitted proposal on redefining the airspace requirements WRT the ADS-B mandate under the Class B airspace & its veil. FWIW I've seen and commented on that proposal in several other forums, so I can that it's received attention.

We fly out to Montana each year from Florida and remain there for a while. You are welcome to PM me if you can get me closer to understanding the geographic area for which you are still trying to collect ground station details. I'm using a Stratus II and FF.

Jack
 
John, thank you for your efforts on this issue. And for your submitted proposal on redefining the airspace requirements WRT the ADS-B mandate under the Class B airspace & its veil. FWIW I've seen and commented on that proposal in several other forums, so I can that it's received attention.

We fly out to Montana each year from Florida and remain there for a while. You are welcome to PM me if you can get me closer to understanding the geographic area for which you are still trying to collect ground station details. I'm using a Stratus II and FF.

Jack

Jack,

You can download the file of ground station locations that I have compiled to ForeFlight. So far, I have collected 510 locations and they can be downloaded from:

https://dl.dropboxusercontent.com/u/58910037/user_waypoints.kml

The instructions for uploading the file to ForeFlight can be found at:

http://www.foreflight.com/support/user-waypoints

The download is a kml file and consists of a user waypoint at each location. With ForeFlight, you can turn on the user waypoint layer to display these on the Map view. Also with Stratus and ForeFlight, there is a Stratus option to display the tower locations of the towers you are actively receiving. If you turn both the user waypoints on and the tower locations on, then there should be a waypoint at every tower you are receiving. If not, then I don't have its location, and I would appreciate obtaining it.

To obtain a new location, you have to display the Stratus Device settings and tap on the Stratus Data "Receiving From x Towers". This will display a list of the tower locations in latitude/longitude format. Take a screen shot of this and email it to me at johncollins52@yahoo.com. It is important to make sure that the format for latitude and longitude is set to DD MM SS before you take the screen shot or I won't be able to use it. A good percent of those who have sent me data have forgotten to do this and I end up asking them to redo it. To set the format to the right format, tap and select: More>Settings>Units/Time>Latitude/Longitude>DD MM SS.
 
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