Missing ADS-B TIS B Traffic?

[Ragsf15e]

Anyone else notice a good amount of TIS-B traffic missing?  I have a GTX345 in/out display on FF ipad and on my GNS 430W.  IFR just outside Seattle class B.  Traffic called by ATC 12 oclock 10 miles, 1000’ above me.  Nothing on TISB.  It showed up just as it passed me and gave me a traffic warning on the 430.  My ADSB report shows the GTX345 is working perfectly.  Now that I watch it, think I see that happening more... Thoughts?

[Marauder]

Anyone else notice a good amount of TIS-B traffic missing?  I have a GTX345 in/out display on FF ipad and on my GNS 430W.  IFR just outside Seattle class B.  Traffic called by ATC 12 oclock 10 miles, 1000’ above me.  Nothing on TISB.  It showed up just as it passed me and gave me a traffic warning on the 430.  My ADSB report shows the GTX345 is working perfectly.  Now that I watch it, think I see that happening more... Thoughts?

Could it be how your TIS-B is set up? There are range rings that will exclude traffic. The NRM, ALL, settings.




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[jaylw314]

28 minutes ago, Ragsf15e said:

Anyone else notice a good amount of TIS-B traffic missing?  I have a GTX345 in/out display on FF ipad and on my GNS 430W.  IFR just outside Seattle class B.  Traffic called by ATC 12 oclock 10 miles, 1000’ above me.  Nothing on TISB.  It showed up just as it passed me and gave me a traffic warning on the 430.  My ADSB report shows the GTX345 is working perfectly.  Now that I watch it, think I see that happening more... Thoughts?

It's unclear in what order traffic data is refreshed via TIS-B, but it's definitely not ordered based on its proximity to you.  The FAA has placed an artificial filter on TIS-B, so only traffic around ADS-B "participants" is broadcast.  As such, I suspect (or guess) some traffic data is not updated frequently enough, and that this is likely to improve once that filter is no longer in place.

[takair]

My guess is that the setting for ADS-B IN capable is not enabled.  Everything will appear normal except what you describe.  This setting is a problem in numerous aircraft and many folks don’t realize they are blind to traffic if a properly set up aircraft does not trigger the ground station.

[Ragsf15e]

18 minutes ago, takair said:

My guess is that the setting for ADS-B IN capable is not enabled.  Everything will appear normal except what you describe.  This setting is a problem in numerous aircraft and many folks don’t realize they are blind to traffic if a properly set up aircraft does not trigger the ground station.

My initial internet search came up with that as well, but I figured it’s likely set up correctly as my 345 is in/out.  I thought this was more a problem for folks with a 330, out only who are using a portable in solution.  I’ll have to figure out how to get to that setup menu though... 

[Ragsf15e]

2 hours ago, Marauder said:

 

Could it be how your TIS-B is set up? There are range rings that will exclude traffic. The NRM, ALL, settings.




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I’ve seen those settings and don’t think so.  Both the 430 and FF show non adsb traffic far away- from someone else’s “puck” so I’m showing traffic farther away than this guy was... and he went right by me.  Was definitely weird.  Flight following (or ifr) still good!  Oh, and looking outside is nice too!

[takair]

14 minutes ago, Ragsf15e said:

My initial internet search came up with that as well, but I figured it’s likely set up correctly as my 345 is in/out.  I thought this was more a problem for folks with a 330, out only who are using a portable in solution.  I’ll have to figure out how to get to that setup menu though... 

I suspect, but am not 100% sure (for this transponder) that this setting is for the OUT portion to tell the ground station to reply with traffic.  You can google for an install manual on line....so your avionics shop can check the setting. :-)

[larryb]

Those "IN" settings tell the ground station what to send back to your aircraft. I expect both of those are set to YES for a GTX345.

 

Lets say you have your GTX345 and N1234 has a GDL88 broadcasting UAT. You can receive N1234 directly so you don't need the ground station to relay his info.

 

Now, lets say you have a 1090-only device. N1234's GDL88 data is going to have to be relayed to you by the ground station for you to receive it.

 

I would verify the settings in the GTX345 setup. If they are correct I would assume this missing traffic was a glitch somewhere in the FAA system.

[EricJ]

I have traffic on my IFD540 display which comes from an in-panel FreeFlight Ranger, and on the two tablets I fly with that get traffic from my Stratux.   There are often differences between them, and sometimes there'll be a target on one that isn't on the other, and it goes both ways.   There are subtle differences of why that can happen, and it does often enough to not be unusual.

It's one of the reasons I fly with that much redundancy, because around here you can use all the help you can get when it comes to traffic awareness.

 

[Ragsf15e]

1 hour ago, EricJ said:

I have traffic on my IFD540 display which comes from an in-panel FreeFlight Ranger, and on the two tablets I fly with that get traffic from my Stratux.   There are often differences between them, and sometimes there'll be a target on one that isn't on the other, and it goes both ways.   There are subtle differences of why that can happen, and it does often enough to not be unusual.

It's one of the reasons I fly with that much redundancy, because around here you can use all the help you can get when it comes to traffic awareness.

 

Yep, that definitely happens on my GNS430 as it will only display a limited number of traffic and at certain ranges.  Usually it prioritizes well and it’s not an issue.  I also use ForeFlight and it seems to display all the traffic.  In this case, traffic didn’t show on either.

[MBDiagMan]

We have SEEMED to have a few times when it appeared that something was wtong because of seeing no traffic, then things seemed to correct themselves and traffic shows up normally.  I have suspected it to be early testing or maintenance of some sort.

[Ragsf15e]

So my “avionics shop” checked the settings today when I went up for a little scenic flight around the NW mountains... settings all good.  Configured for both 1090 and UAT ADSB In.  Seems like I was seeing traffic in my own “puck”.  I’m really starting to think the FAA towers/ADSB/TIS B infrastructure isn’t 100% perfect and there’s a good chance some data (traffic) could be missed without warning.

[MBDiagMan]

There is a setting in FF available when connected to the 345 that limits visible traffic to only the traffic in your hockey puck.  I don’t remember the exact name, but it is something like “Hide Distant Traffic.”

Hope this helps.

[takair]

2 hours ago, Ragsf15e said:

So my “avionics shop” checked the settings today when I went up for a little scenic flight around the NW mountains... settings all good.  Configured for both 1090 and UAT ADSB In.  Seems like I was seeing traffic in my own “puck”.  I’m really starting to think the FAA towers/ADSB/TIS B infrastructure isn’t 100% perfect and there’s a good chance some data (traffic) could be missed without warning.

In our area I have been impressed with how complete the traffic picture has been.  I did come across a guy with no transponder that was invisible, but. He was talking to ATC and was no factor.  Perhaps worth asking around local pilots to see if others have run into this.

[StevenL757]

On 3/11/2019 at 6:52 PM, Ragsf15e said:

Anyone else notice a good amount of TIS-B traffic missing?  I have a GTX345 in/out display on FF ipad and on my GNS 430W.  IFR just outside Seattle class B.  Traffic called by ATC 12 oclock 10 miles, 1000’ above me.  Nothing on TISB.  It showed up just as it passed me and gave me a traffic warning on the 430.  My ADSB report shows the GTX345 is working perfectly.  Now that I watch it, think I see that happening more... Thoughts?

Might be water under the bridge, but for what you paid for the 345, did you give any thought to the NGT-9000+ ?

A little more money, but gives you ADSB in and out, Mode-S ES, weather, and active traffic that scans out 35 miles.  Use it with ForeFlight, and beats equipping with a separate active traffic/TCAS option at easily over $10k.

Steve

[Ragsf15e]

48 minutes ago, StevenL757 said:

Might be water under the bridge, but for what you paid for the 345, did you give any thought to the NGT-9000+ ?

A little more money, but gives you ADSB in and out, Mode-S ES, weather, and active traffic that scans out 35 miles.  Use it with ForeFlight, and beats equipping with a separate active traffic/TCAS option at easily over $10k.

Steve

Yep. Was maxing my budget and keeping with the garmin theme in my panel.  The active traffic might be nice, below radar or ads b coverage, but the -345 has everything else just the same.  I’m happy with the unit, I’m just a little more skeptical of the tis b I’m getting back from the FAA which is probably healthy.

[MBDiagMan]

I have had second thoughts about the 345 and whether I should have gotten the NG9000, but it was a $1,000 more at the time I did it.  Defending the 345 though, if you have a 430/530 or 650/750 you have the same information displayed as seen on the L3 unit.  Even with Foreflight you will have it.

[carusoam]

MBD...

You have found the eternal MS struggle...

The answer isn’t very hard.

You have to compare yourself to other MSers...

1) Do you like reading equipment specs?

2) Can you remember 50 lines of specs from each vendor?

3) Are you adept at integrating electronic devices... home stereos, televisions, video games, DVD players, etc...

4) Do you look forward to getting the newest box each year?

5) Or do you hate when a box literally gets too old compared to the industry? What is that new TV plug that all the new devices use called? Whatever happened to RGB cables...?

 

There is a great company that makes the best audio panel and gives great support on MS...

There is a great company that makes the best engine monitor and gives great support on MS...

There is a great company that makes the best Transponder...

There is a great company that makes the best spare digital AI...

There is a great company that makes the best... Transponder...

 

Then, there is Big G... that makes some pretty good stuff that is mostly integrated nearly all of the time...

It is hard to go wrong choosing the fully integrated route... don’t look back...

The benefit of going with Big G... you are not alone... when a version of software fails... people are sharing the knowledge quickly...

The draw back of a highly individual collection of the best devices... your collection of devices is going to be unique compared to the next MSer... you might be the only one with this particular integration challenge...

How good do you want to be at integrating electronic boxes?  Hanging out with Marauder at a box maker’s presentation is a blast! 

PP thoughts only, not an electronics technician...

Best regards,

-a-