khedrei Posted June 6, 2020 Report Share Posted June 6, 2020 Now I know this isn't a new problem. 2-3 years ago I flew with a friend in his Mooney. He had ADSB out on his Xponder (an Avidyne) and he had a home made ADSB in (Stratus box maybe?) and he was able to get ADSB traffic and weather on his IPAD using Foreflight through wifi. It would not display on any of his panel mounted avionics. Now, I understand the basics behind it. It has something to do with the Mode C transponder sending signal to the ADSB ground stations and the GPS position that you are also sending don't match up perfectly with your radar position so you get a ghost target and a traffic warning. Usually it is almost the same alt and behind you. My understanding is that these home made systems aren't as good, and some reading on the Vans forums and other articles described a way that Foreflight is able to filter it out using its algorithms and gave suggestions on how to adjust the settings Not sure how it's done and it doesn't matter to me because I don't use it. My understanding from these articles is that this is generally only a problem for people who do not have ADSB IN and OUT operating in the same system. If it is in the same system, it is supposed to be smart enough to filter out ghost targets and will not give you warnings. I have just recently upgraded to one of those systems. All Garmin, full glass with a remote diversity in/out transponder. I live only about 30NM (as the crow flies) from the US border which starts in the middle of Lake Ontario so US soil is about 50ish NM away. Depending on my altitude I have no trouble receiving US ADSB weather on my system even 100NM North of the border. So even at 2500 feet close to home I am likely in range of US ground stations. What this long story is getting to is.... I was up the other day and I was getting NON STOP traffic warnings for my own plane. In the 45 minute flight it happened at least 10 times. Then none on the way home. In the 15 or so flights since the upgrade I had it only happen once I think. Funny thing, during this flight I was talking to the same friend (ATC controller) and he said that it was happening to him non stop just a day or two before. Then, a student of mine called me and said it happened to him in his plane just a couple days later. Both of them, non-stop. They both terminated their flights early it was so annoying. We all have a different brand of systems but we all have on board ADSB in and out. Anyone have any insight? Could the cloud cover or weather have something to do with it. There was a thick broken cumulus layer not far above us that day and it had mostly cleared up for the trip home. Perhaps that's why I didn't get anything on the way back. Has there been an issue or lag in the ADSB system recently? Could that be why we have all had the same issue in the last week or so? Regardless, does anyone know the technicals on how the system filters out ghost targets and if something possibly needs to be adjusted in any settings? Ready... Set.... GO! Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 6, 2020 Report Share Posted June 6, 2020 Find the button on your iPad app to turn that feature off... Own plane(?) So you don’t see your own plane... The reason the ghost is following you... is the lag that the system has overall.... no idea why it is a problem on some days, and not on others... Terminating a flight early for annoying warnings? Go old style... comfortably look out the windows with both Mark I eyeballs... PP thoughts only, not an ADSB in guru... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
khedrei Posted June 7, 2020 Author Report Share Posted June 7, 2020 It's not on my ipad. It's on my panel mounted equipement. I can mute each earning when they come... sort of. The system still finishes saying it once. I'm not sure there is a way to mute them all but I'm not sure I would want to anyway. Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 7, 2020 Report Share Posted June 7, 2020 Which system is doing it? We have several people that will be sharing The same hardware Around here... With all the magic and computing power there is, there is no reason to be stuck with an own ship ghost... Lets find the proper way to turn it off... Which... display do you have? ADSB in do you have? Software revisions too... It’s probably going to be a combination of these... -a- Quote Link to comment Share on other sites More sharing options...
takair Posted June 7, 2020 Report Share Posted June 7, 2020 I suspect, but not sure, that you are seeing a significantly more delayed response to your ownship than we see in the better coverage of the US. The ADS-B stations respond to aircraft that are within a given “puck” or range of a station. Because you are likely out of this puck you are reliant on another aircraft to activate that site and transmit traffic. Because of delays, your ownship May be a couple seconds behind and the filter may not be able to filter. You should also make sure your aircraft ADS-B out is strapped to tell the ADS-B station that you are ADS-B IN capable. I’ve seen a few aircraft that see this problem and they don’t see all traffic around them. It is less obvious now that most aircraft are equipped. Quote Link to comment Share on other sites More sharing options...
EricJ Posted June 7, 2020 Report Share Posted June 7, 2020 Usually it is getting the system to exclude listening to the ADS-B uplink report about your own airplane. This happens regardless of the system, cheap, expensive, stand-alone or in-panel. As mentioned, figure out how to filter out your own ship in the system. Usually this involves finding your transponder hex code and entering it in an appropriate spot so the the system ignores that in the uplink. Quote Link to comment Share on other sites More sharing options...
khedrei Posted June 7, 2020 Author Report Share Posted June 7, 2020 I'll look into the above suggestions, checking settings and trying to filter out my own transponder. What I find odd is that this isnt the first time I've flown that route at 2500 feet but it is the first time ive had warnings out of control like that. Quote Link to comment Share on other sites More sharing options...
ohdub Posted June 7, 2020 Report Share Posted June 7, 2020 I had a Lynx 9000+ installed last fall. It had worked perfectly until last week when this issue began. (I'm the friend Kevin is referring to). I contacted my avionics shop to report what was happening and they have received identical reports from 4 other aircraft. They forwarded this to L3 in case this is an issue with the Lynx. They've been looking into it and believe that it is a malfunctioning ads-b ground station. Hopefully this will get resolved soon because it is very distracting/annoying when you get aural traffic alerts every 10-20 seconds. Unfortunately the Lynx has no means of turning off aural alerts, you can only hit the mute button when an alert occurs. I believe that it may in fact be a malfunctioning ground station in the Buffalo/Niagara area, I did one flight last week where the alerts suddenly stopped as I was flying away from that area (about 60nm away) and they resumed in almost the same spot on the return flight home. Quote Link to comment Share on other sites More sharing options...
carusoam Posted June 7, 2020 Report Share Posted June 7, 2020 That’s interesting... Is there an FAA Or CAA website to check for ADSB availability? My web search didn’t find what I was asking for... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
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