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ADSB in/out Ghosting in Florida

Aerosport1

Well Known Member
Just curious if anyone flying down in the Florida area with ADS-b in/out has noticed that they are seeing ghosting on there unit. I have been down to Florida
3 times since October and had not noticed this until my last trip last week.
I have a Navworks in/out and a Stratus for my IPad as well and it shows up on both. I seemed to notice that it possibly went from around Macon Georgia south to KLAL. I did not notice it south of KLAL down to KFMY. Another flyer with a different ADS-B unit from mine with in/out was complaining his was showing the ghosting as well. We were flying together a month ago and had no ghosting.
I get no ghosting North of Macon.

Any Thoughts

Geoff
 
This is typically a function of the equipment installed to filter out your own ship.

Some systems appear to be better than others at doing that under all the various conditions.
 
I agree with Brian.

I had ghosting after an ADSb OUT upgrade, but after I got the settings correct on both my 330 and GDU375 I haven't seen any ghosting.
 
A couple of hundred hours in the last year and a half flying in Central Florida an I have never had ghosting with my full Garmin panel.
 
I have had my ADS-b installed for over 2.5 yrs and has worked fine. The Ghosting is not because something is not set correctly. I have flown all over the country with this system and works fine. As I said in my prior post that Myself and another person living in Central Florida has noticed that the ghosting has recently started up in this area. 30 days ago there was none. I was in central Florida last month same systems same area and no ghosting. I think it is actually a filtering issue with the ground stations In that area.
I have a Friend that works for one of the Universities here in Ohio that has been doing testing on the ADS-b systems and spoke with him and he also said it is probably a ground station issue. My understanding is they can change settings and then cause these issues. This happened up in Ohio about 1.5yrs ago and it
lasted for about 30 days and then was gone.
I am just seeing if anyone else that has flown in this area near Ocala, Lakeland has noticed this in the last couple weeks.
 
I have had my ADS-b installed for over 2.5 yrs and has worked fine. The Ghosting is not because something is not set correctly. I have flown all over the country with this system and works fine. As I said in my prior post that Myself and another person living in Central Florida has noticed that the ghosting has recently started up in this area. 30 days ago there was none. I was in central Florida last month same systems same area and no ghosting. I think it is actually a filtering issue with the ground stations In that area.
I have a Friend that works for one of the Universities here in Ohio that has been doing testing on the ADS-b systems and spoke with him and he also said it is probably a ground station issue. My understanding is they can change settings and then cause these issues. This happened up in Ohio about 1.5yrs ago and it
lasted for about 30 days and then was gone.
I am just seeing if anyone else that has flown in this area near Ocala, Lakeland has noticed this in the last couple weeks.

The algorithm used by different manufacturers to filter your own ship out most likely is very proprietary and somewhat unique.

That being said, your system may have issues with ghosting in a particular area where others may not.

I can imagine that there are many variables that could cause ghosting.

Latency thru the system could be a very likely reason for ghosting because if you move too far away from your broadcast position by the time that signal gets to you, your system's own ship detection may not filter it out.

The way I understand it, most if not all of the own ship filtering is a function of the receiver not the ground station.

I agree however that ground stations issues can cause all kinds of havoc with ADS-B services. There are suppose to be NOTAMS issued for ground station problems but that seems to be hit or miss. It does seem to be getting better as time goes by however.
 
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In the Phoenix area I do at times get ghosting with my navworx and advanced flight systems. it used to happen more often but now only occasionally, it usually is in the class B area and seems to me that it is probably the base station because there is no consistency to it. sometimes it happens for five minutes then for 20 minutes every once a while. If it were the aircraft systems fault I would think it would do it all the time. So there is no misunderstanding I am very happy with both of my systems and Believe they are working properly. Larry
 
We've had a few reports of ghosting recently, and most have been in that area as well, so it does likely indicate something unique is up. In the datalogs we have seen, something very odd is happening.
 
Ghosting around Orlando

I have a RV10 with NavWorx ADS600 and get ghosting around the Orlando class B airspace and it goes away when I get south of it 10 or 15 miles. I have been coast to coast and had it a few times, but it usually goes away in a new radar sector
 
I have had this issue for the last several flights in the Columbia, SC area. Not a problem until recently. I gave up trying to outrun and outmanuever my ghost. He's good!
 
We've had a few reports of ghosting recently, and most have been in that area as well, so it does likely indicate something unique is up. In the datalogs we have seen, something very odd is happening.

I am getting ghosting on TIS in NJ. Is that the same problem or is that different altogether?
 
Me to @ KCUB/KCAE

I have had this issue for the last several flights in the Columbia, SC area. Not a problem until recently. I gave up trying to outrun and outmanuever my ghost. He's good!

Same as Mike here in Columbia, SC.

Mike has Dynon equipment.
I have GRT equipment.

Previously all worked fine.
I too noticed it within the last 30 days or so.

Also have a friend in the Brooksville/Tampa area whose system that had previously worked fine, now has ghosting.

I wonder if there was a recent upgrade of software to the ground stations.

Anybody on the list here know?????

James
p.s. THe ghosting **MIGHT** have gone away when I had flight following that required a frequency change to controllers at a different location. I need to verify that.
 
James and Mike
Have you guys flown north recently up towards Spartanburg. If so did you have ghosting. I notice my ghosting went away once I got about 20 miles north of Macon. I tracked this
Ghosting all the way home Sunday. KFMY fort myers to KLHQ. My ghosting started around KLAL. South of there I did not see any. Curious if anyone that flys regularly south of KLAL has noticed any ghosting in the past 30 days

Geoff
 
James and Mike
Have you guys flown north recently up towards Spartanburg. If so did you have ghosting. I notice my ghosting went away once I got about 20 miles north of Macon. I tracked this
Ghosting all the way home Sunday. KFMY fort myers to KLHQ. My ghosting started around KLAL. South of there I did not see any. Curious if anyone that flys regularly south of KLAL has noticed any ghosting in the past 30 days

Geoff

Geoff, I departed X35 to APF Sunday about an hour after you and flew right over LAL. No ghosting the entire way home.
 
I've been flying throughout my local area around Pensacola without any problems using my NavWorX system. Of all the equipment in the aircraft, this one I love the most. In this high training area, this equipment is so helpful in spotting hard to see, fast moving aircraft. I've never seen any Ghosts on the screen around Pensacola, that was until Monday morning. Flying north out of Pensacola, I had a Ghost until I was about 50 miles out. Then the Ghost stopped. I can't remember if it was after a squawk change or not. I did have another episode of Ghosting nearly a year ago around Knoxville, TN. When I talked to NavWorX, I remember then asking me my squawk code at the time. Therefore, assigned squawk codes may have something to do with Ghosting.
 
I found an FAA document on Google, that now I can't find again. Here's a paraphrase of what it said:

The FAA ground stations get data from UAT out, Mode S-ES out, and ground based radar. The software is supposed to identify the aircraft and merge the data together, so that if there is both a 1200 mode C radar target and an ADSB-out target for the same aircraft, only the ADSB data is sent out on the uplink to ADSB-in aircraft receivers. The ADSB data has N numbers attached to it, so aircraft receivers can easily identify it as themselves and filter it out. However, sometimes the software fails and sends both ADSB data and radar data out the uplink. In this case, the radar data may show as a "ghost" on ads-in systems, since it is an unidentified target.

So my question: when you see a ghost, do you ever see your N number associated with it? If the answer is no, then the above may be an explanation.

An interesting test, for those with UAT systems, would be to turn off your mode C transponder and see if the ghost goes away. (Of course this is illegal unless you happen to be in one of the few remaining areas of uncontrolled airspace).
 
Bob
I do not see my N-number when getting the ghost. However what's interesting is that with the stratus 2 I also have when I first open up foreflight after having
it off I will see my N-number for a couple seconds than the N-number goes away but the ghost still remains.


Thanks Geoff
 
Earlier this week, I made a flight from Michigan to southern Ohio. I used flight following all the way down and had ghosting about half the time.

On the return trip about two hours later, I didn't use flight following and had zero ghosting! Traveled the exact route, 7500' going south and 8500' traveling back north.

Is there a connection?

Data points:

GRT HX
Sky-Radar D2 ADS-B receiver
 
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No more ghosting!

In recent weeks I have been experiencing the same problem as Geoff with own ships transponder Ghosting in central Florida. It was pretty consistent for me there for a while although at times it would go away during flight and then re-appear minutes later.

It is very annoying, not to mention distracting, to have the 2 mile warning window pop up as it does on the GRT HX screens when all it is indicating is your own airplane.

However, I am happy to report that I saw no ghosting on a 150nm trip from Dunnellon airport (X35) in central Florida to Ft. Meyers (KFMY) in South Florida on Thursday morning and returning today.

At first I thought I had an equipment problem but based on previous posts and this experience it seems to me that the ADS-B system might have had issues and that they have been fixed.
 
Earlier this week, I made a flight from Michigan to southern Ohio. I used flight following all the way down and had ghosting about half the time.

On the return trip about two hours later, I didn't use flight following and had zero ghosting! Traveled the exact route, 7500' going south and 8500' traveling back north.

Is there a connection?

Data points:

GRT HX
Sky-Radar D2 ADS-B receiver

If you do not have ADSB-out, then:
1. Traffic data will be intermittant, and
2. You should expect ghosting. The times with no ghosting may just be the times when you're not getting traffic data.
 
Anyone using a GDL-39 ever seen any ghosting? If so what is your particular setup?

I have only twice. One time for a few seconds while doing aerobatics ~40 miles East of KTYS.
The second was on a trip back from Osh while passing a large white puffy cumulonimbus buildup 5.6 miles north of KDNV. I have no idea why that would cause it but the ghost appeared to be in the cloud as I passed by.

That was several firmware revisions ago and before I got my test report back from the FAA/ADS-B guy letting me know that I had my GPS integrity set to 1E-5 instead of the correct 1E-7 and the GTN set to ADS-B instead of ADS-B+.

Setup: G3X Touch, GDL-39 3D, GTN650, GTX23ES
 
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Bob,

I get traffic without ghosting. In fact I get everything from Cessnas close to the ground to airliners in the flight levels.

I plan to do a lot more data gathering over the next few days now that the weather is getting better:)
 
Bob,

I get traffic without ghosting. In fact I get everything from Cessnas close to the ground to airliners in the flight levels.

I plan to do a lot more data gathering over the next few days now that the weather is getting better:)

Ghosting happens when your 'unknown' 1200 mode C target is sent up to 'participating' aircraft which happen to be near you (15 miles, 3500' I think), and the Skyradar intercepts that transmission. Very high or low aircraft, compared to you, won't cause a ghost. Try this: Go into the HX set up and turn on the traffic filter to, say, plus/minus 3000'. Set your map range to 15 miles. My guess is if you see traffic now, with an N number attached (so he has ADSB-out), you'll also see a ghost. And you may visually see traffic not reported by ADSB. If you do not have 'out' the ground station won't send you data.
 
I had similar issues with an early version of the GDL39, thanks to the G3X team guys I was able to swap it out for a 39R and I haven't had any issues since.
 
This is an old thread but it's very relevant to what I experienced yesterday. I only have about 20 hours in this aircraft and only 20 hours total experience with ADS-IN (the aircraft I'm paid to fly only have ADS Out).

Yesterday, in central FL, while descending into X06, I had a ghost ADS reply that showed anywhere from my exact altitude to within 200 feet of my altitude and virtually at my exact position.

There was no traffic call from the system but it scared the carp out of me. I immediately turned and arrested my decent but the ghost return stayed with me for a short while and then vanished.

Equipment is a GDL39, GTX-23ES and two GDU-370's.
 
This is an old thread but it's very relevant to what I experienced yesterday. I only have about 20 hours in this aircraft and only 20 hours total experience with ADS-IN (the aircraft I'm paid to fly only have ADS Out).

Yesterday, in central FL, while descending into X06, I had a ghost ADS reply that showed anywhere from my exact altitude to within 200 feet of my altitude and virtually at my exact position.

There was no traffic call from the system but it scared the carp out of me. I immediately turned and arrested my decent but the ghost return stayed with me for a short while and then vanished.

Equipment is a GDL39, GTX-23ES and two GDU-370's.

More than likely your own ADS-B signal is getting reported by two different ground stations with slightly different position locations due to ground station latency. Check your settings and make sure your system disregards your tail number for traffic alarm purposes.
 
More than likely your own ADS-B signal is getting reported by two different ground stations with slightly different position locations due to ground station latency. Check your settings and make sure your system disregards your tail number for traffic alarm purposes.

I'm not sure what setting that would be but I'll look into it. Thanks.

Yesterday was the first time I've had this occur.
 
I'm not sure what setting that would be but I'll look into it. Thanks.

Yesterday was the first time I've had this occur.

Even if everything is configured correctly, this can happen once in a while. It should be VERY rare but it can happen, especially in certain areas when you are receiving data from two or more ADS-B ground stations. If it happens again, in the same area and altitude, check to see if the traffic shows your own tail number. This will confirm or eliminate this possibility.

Now you get an idea while ADS-B is a tool and NOT to be used exclusively. The only thing 100% infallible are still your eyes outside the cockpit.

;)
 
Even if everything is configured correctly, this can happen once in a while. It should be VERY rare but it can happen, especially in certain areas when you are receiving data from two or more ADS-B ground stations. If it happens again, in the same area and altitude, check to see if the traffic shows your own tail number. This will confirm or eliminate this possibility.

Now you get an idea while ADS-B is a tool and NOT to be used exclusively. The only thing 100% infallible are still your eyes outside the cockpit.

;)
Thanks. I've been flying with TCAS for years. I'm aware of the limitations of technology.
 
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