TIS Only Problem

[jc2da]

Merry Xmas! I have a perplexing problem. A few weeks ago, the only change made was to replace my SV10 screen with a Touch screen. Pull old one out and new one in.

Since that change, I realize that over the last several flights, I have not had the more complete traffic picture with ADS-B Traffic. The map says "TIS Only" instead of the more typical "ADS-B OK". I have searched and searched without luck to get the ADS-B OK message again. I know i am not getting the "full" normal picture since nothing at SFO shows, which i would always see traffic for.

All ADS-B Status messages say ok. I am getting Weather updates fine. In fact on the ADS-B Status page, it says 2,000+ traffic targets received. SV-XPNDR is fully functional and working fine. I can see it is transmitting and receiving and on AUTO.

Any ideas? It must be something simple???

Thanks and Merry Xmas!

 

[dynonsupport]

Check your traffic settings:

SETUP MENU > TRAFFIC SETUP

Make sure you're set to display all traffic.

Merry Xmas! I have a perplexing problem. A few weeks ago, the only change made was to replace my SV10 screen with a Touch screen. Pull old one out and new one in.

Since that change, I realize that over the last several flights, I have not had the more complete traffic picture with ADS-B Traffic. The map says "TIS Only" instead of the more typical "ADS-B OK". I have searched and searched without luck to get the ADS-B OK message again. I know i am not getting the "full" normal picture since nothing at SFO shows, which i would always see traffic for.

All ADS-B Status messages say ok. I am getting Weather updates fine. In fact on the ADS-B Status page, it says 2,000+ traffic targets received. SV-XPNDR is fully functional and working fine. I can see it is transmitting and receiving and on AUTO.

Any ideas? It must be something simple???

Thanks and Merry Xmas!

 

[jc2da]

Yes pretty certain my traffic setup is set to Show All. Next time i fly, i will try booting without the new screen, since that was the only change. See if ADS-B traffic comes back or not.

 

[jc2da]

Still no luck. I am going to try reloading all the firmware and force reloading the network. No ADS-B on the ground, so i am going to try flying to an airport that should get an ADS-B signal on the ground. Trying to work thru setup menus while in the air is not ideal. Frustrating.

 

[dynonsupport]

Jae,

1) TIS OK means you have switched down from ADS-B to TIS-A that is built into your transponder. SkyView does this because TIS-A is superior to partial ADS-B coverage. In this mode, you're not using ADS-B traffic at all.

The way we know if you are getting a full traffic picture is if the ADS-B ground station tells us you are. It does this by sending up your ICAO address every now and then saying "for airplane XXXXXX, we are giving it a full traffic picture". Without this data, we assume your ADS-B traffic will be incomplete, so we prefer TIS-A. If you aren't in a TIS-A service volume, then we fail back to ADS-B, which is shown as "ADS-B partial".

To get ADS-B to see you and tell us you have full traffic, the following needs to be true:

1) You are ADS-B out (The Dynon transponder is)
2) Your ADS-B out has the right ICAO address and tail number.
3) You are transmitting ADS-B position and it's marked valid.
4) You are in ALT mode and your transponder is working right, which it is if you are getting TIS-A
5) You are in a radar service volume where you can be seen with standard radar, which it is if you are getting TIS-A
6) Starting in February, you have a SIL and SDA greater than zero.


So, possibilities:

1) Your ICAO and/or tail number are wrong.
2) Your ADS-B GPS position is mis-configured and the transponder is not transmitting position. Go into the transponder menu and make sure it says the position is OK
3) The FAA has turned on the SIL>0 requirement early in your area and you'll need Dynon's update to enable this. We have not heard of this from the FAA however.

Getting a portable ADS-B receiver won't prove anything. It will be getting traffic, but it will be incomplete. We're actively ignoring this traffic right now because you can get TIS-A which is a complete picture of any threats to your aircraft.

All else fails, get us a datalog of a flight and we can look at your settings and what we were getting back from ADS-B and debug it.

 

[jc2da]

>To get ADS-B to see you and tell us you have full traffic, the following needs to be true:

>1) You are ADS-B out (The Dynon transponder is)

Yes, i have the SV-XPNDR-261

>2) Your ADS-B out has the right ICAO address and tail number.

Yes, see screenshot. I verified both screens showing the same N996JC and aircraft hex code ADE9B8. Verified this is set correctly in the Aircraft Information page as well as the Transponder setup page.

> 3) You are transmitting ADS-B position and it's marked valid.

Yes, see screenshot below. Position source is SKYVIEW and status shows OK.

> 4) You are in ALT mode and your transponder is working right, which it is if you are getting TIS-A

Yes, verified in ALT mode and transmitting/receiving.

> 5) You are in a radar service volume where you can be seen with standard radar, which it is if you are getting TIS-A

Yes, see screenshot. I also verified with a Stratus.

> 6) Starting in February, you have a SIL and SDA greater than zero.

I haven't done any changes at all for 2020. Only change has been the upgrade to the SVTouch screen.

> So, possibilities:

> 1) Your ICAO and/or tail number are wrong.

No changes. I verified N996JC and hex code ADE9B8. Docs say the N is required for US aircraft.

> 2) Your ADS-B GPS position is mis-configured and the transponder is not transmitting position. Go into the transponder menu and make sure it says the position is OK

Using SKYVIEW and it says OK.

>3) The FAA has turned on the SIL>0 requirement early in your area and you'll need Dynon's update to enable this. We have not heard of this from the FAA however.

????

The only thing that changed from working to not working was upgrading the screen from SV to SVTouch. I have tried turning the new touch screen off in flight. However, next time, i need to remove the Touch screen entirely from the airplane and test it.

This is also weird. This next screenshot shows ADS-B traffic (because I can see N numbers). However, the status in the bottom corner says ADS-B NO RADAR. Why should this be?

Then a couple minutes later, TIS ONLY pops up, and all the ADS-B traffic disappears. ARGH.

link to album is here https://goo.gl/photos/v7ATHxktjPMdergE7

 

[jc2da]

I want to point out once again, why does this screenshot say ADS-B NO RADAR, when I am seeing traffic radar, it seems to me. It is consistent with the Stratus, too.

However, you can see the ghost image and the traffic alert on myself, too. Clearly, there is something wrong here.

Also, just uploaded the diagnostics zip file.

 

[dynonsupport]

Jae,
NO RADAR means the ADS-B ground station has not marked your aircraft as one that it knows about and is currently covered by radar. This means that you don't have any guarantee of seeing planes without ADS-B OUT (ones with only Mode-C onboard). It doesn't mean you won't see any traffic, it just means the system isn't promising you that it will be able to report a threat to you.

This happens when you are in radar coverage but the ground station hasn't acknowledged you as a ADS-B IN equipped aircraft. As far as we can tell, everything is configured correctly. We've written the FAA to ask if anything has changed in the SFO area and to look at your data and see if they can tell us anything.

As an FYI, while the traffic "goes away" when you switch to TIS OK, that's because TIS only shows you planes that are a threat to you, and that traffic 15 NM away just isn't an issue. While it isn't as fun to look at, you can rest assured that if you have TIS OK you have just as good of information about threat aircraft as you would have if you were ADS-B FULL.

 

[jc2da]

This happens when you are in radar coverage but the ground station hasn't acknowledged you as a ADS-B IN equipped aircraft.

Did you mean to say that the ground station hasnt recognized me as an ADS-B OUT aircraft? Hmm, that is quite interesting.

Related to this, when I installed the upgraded SVT screen, i noticed that it forced an SV-XPNDR-261 upgrade of some sort. I can't recall the specifics of the message, though.

Also, during flight, if I turn off the upgraded SVT screen, i noticed that my XPNDR X's out, ie disabled. Thus, i am assuming the upgraded SVT screen is somehow controlling the XPNDR. Unfortunately, when the other SVT screen takes over, there is no noticeable improvement with ADS-B traffic.

Anyway, i am somewhat suspicious of the automatic "upgrade" of the XPNDR. I just cant recall if it was the firmware, software, etc. Can't remember.

 

[dynonsupport]

SkyView doesn't automatically do an upgrade of the transponder or force it. You have to press a button in the transponder menu. In any case, your transponder is on the latest version, and we know of no issues with that.

The short term loss of the transponder when power cycling one screen is expected. The screens share configurations so which one is driving the transponder should make no difference.

 

[jc2da]

SkyView doesn't automatically do an upgrade of the transponder or force it. You have to press a button in the transponder menu. In any case, your transponder is on the latest version, and we know of no issues with that.

The short term loss of the transponder when power cycling one screen is expected. The screens share configurations so which one is driving the transponder should make no difference.

Yes, correct. I was just clarifying "things" that may have changed. I had said earlier that the SVT upgrade was the only change. However, in fact, I did force the transponder upgrade during that same time when I noticed the message that an upgrade was available. It was a momentary brain blip on my part, but unfortunately, too late to take back at the time.

Just trying to help narrow things down. Thanks for the recent replies to my queries!

Also, just reviewed the changes from SV-XPNDR SWv2.04 to 2.06, the latest. It seems like it was related to the ADS-B to ADS-B+ support for GNS and GTN navigators. I am not configured to use either. It doesnt seem like this XPNDR update should have affected anything specific to me, anyway.

 

[davelmalibu]

We are in the Los Angeles area, specifically Ventura. We have also noticed this same ATS-B display and behavior. We did not make any changes to our settings or equipment, so we are assuming that this is something new from ATC. Additionally, we are frequently getting a ghost target of our own airplane. So, we assumed the FAA is not continuously recognizing us as ATS-B out. 

 

[bajapilot]

I'm so happy I came across this thread.  I am having the same problem flying in the NorCal area.  I though this was only a problem with my aircraft.

About two weeks ago I upgraded my RV-12 with the new Autopilot/Knobs panel.  I also upgraded several software modules per Vans instructions when doing the install.  Since then my ADS-B will only give me TIS OK and a partial traffic picture.  I though that I had induced the problem somehow during my hardware upgrade although I could't see how.  Have been trying to track down the problem but now seems that this is a local problem.

I am also getting the ghosting problem others are describing as well as incomplete radar picture.  What say you Dynon?

 

[jc2da]

Wow. Thanks for the updates guys. This makes it a total of 3 affected. 2 in norcal and 1 in socal. DRL says no changes at all, and the exact same symptoms.

I truly doubted it could be a ground station issue but given the 3 total experiences, it is pointing more and more in that direction now.

 

[meyerflyer]

Im flying a Lancair 320 out of Redding CA, and just started having the same ghosting Problem. Im running the latest SV software with a single SV 10" screen. :-[

 

[rlmarshall]

I was holding short the other day at KSMX (Central Calif. Coast) when landing traffic showed a ghost--the target and ghost separated near touch down and it appeared the ghost did a "missed approach" before finally disappearing. Very strange. I have never had ghost problems with my SV, ADSB, or Transponder.

 

[dynonsupport]

Seeing a target "coast" is not that unusual. Remember that a ground radar sweeps as slow as 12 seconds. When that plane descends below radar coverage, the radar doesn't even see that for 12 seconds and I believe it takes another sweep for it to drop it. So it can take 24 seconds for radar to realize you're gone. In the mean time, the computers coast it based on last velocity and direction.

There is actually a virtual "box" around airports where no airplanes are shown for this very reason, since it's assumed they are landing or taking off. This only apples to TIS-B, and they are sill working on it so you may have caught one of the edge cases.

 

[Dennis54]

I've just arrived in NoCal (from Virginia) and have noticed the same issue. As I'd had virtually continuous ADS-B coverage all across the US, I'd sort of 'assumed' a local issue but nice to have it confirmed!

 

[65xx]

Guys: If we are keeping count on "ghost traffic", I fly out of Reno Stead and have just recently started getting traffic alert with the "traffic" overlaid on top of my aircraft symbol at "00" altitude. I have the full Dynon suite of ADS-B equipment. NorCal is the radar service provider. Dan

 

[swatson999]

SoCal here...same issue.