NGT9000+ can’t detect non-adsb acft

[Airways]

I got a NGT9000+ with the NY164 active antenna.  The system detects all acft with ADS-B xpdrs, but it doesn’t see any mode A/C or mode S equipped acft.

The TAS is definitely unlocked and passes the selftest.  Could it be a problem with the antenna itself then ?  I ruled out blind spots due to placement of the antenna because then at least some acft should show up sometimes.  And yes: mode A/C/S is still a big deal here in Europe :-)

[StevenL757]

How so you know you aren’t receiving any TAS (non-ADSB) targets?  Can you be sure that any non-ADS/B targets have been in your vicinity whilst in flight?

If you’re certain that you’ve had non-ADS/B targets in your vicinity, then any or all of three things is possible here…

• You don’t have the TAS/Active Traffic unlock applied to the unit.  You mention it exists, but I’d verify it from a software perspective.
• Your NY164 is too far aft to the point where your wing is likely shadowing certain areas.
• Your WAAS antenna (the foreground left-most antenna above) for the NGT9000+ position source is too close to the COM blade.  There should be at least 24 inches of space ideally between any COM blade and this antenna.

On a Mooney, the NY164 typically goes above the cockpit…as in the attached example.  This is in alignment with factory drawings showing the recommended proper positioning in this location.  Personally, I would ensure your TAS unlock has been done, and I would move the NY164 to the front, and put the WAAS position source antenna for the NGT where the NY164 is presently.

Edited June 12, 2022 by StevenL757

[Marauder]

I’ll second Steven’s comments about whether or not you are seeing TAS targets. I have noticed a significant drop off of TAS targets over the past couple of years. Also keep in mind Mode A/C are the typical TAS targets. I believe Mode S is treated differently.

Another thing to do is review the limitations that unit puts on TAS reporting. It won’t provide advisories for these targets unless they meet the criteria indicated in the Lynx POH. Here is an example of some of the limitations:





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[Airways]

Thanks for the replies guys.  The TAS targets are definitely there.  They were in contact with flight info and they got traffic information about my presence.  You don’t receive traffic information from our FIS without a working transponder.  I even have a playback from Flightradar 24 where you can see the conflicting traffic and the source of the info (multilateration).  The range of TAS is limited vs ADS-B, but when I’m able to see the colour of the other pilot’s t-shirt, the NGT should at least acknowledge the presence of another acft.  The unlock of TAS is also out of question.  I was there when they performed it, and you really can’t get a green “pass” during the selftest when it’s not unlocked.  I didn’t get the TAWS unlock and during selftest this is clearly shown in red.  So I’d say the system’s logic works.

I was thinking about shadowing of the active antenna, but then the target should show up at some bearing eventually.  This doesn’t happen.  Even targets above me don’t show up, so that can’t be due to shadowing, right ?  There are a lot of mode a/c/s targets flying around in Europe, especially during sunny weekends.  But yesterdag the ngt saw none, nada.  All of the time the freq of the FIS was overloaded though.  Doesn’t compute…

I’m really suspecting the active antenna.  It doesn’t perform.  Is it possible the antenna passes the ngt self-test without receiving power ?

Does the antenna need a separate circuit breaker or does it get its juice from the ngt ?

[StevenL757]

So a few things about this...

• The antenna itself doesn't pass self-test...the unit passes the TAS self-test when the TAS portion of the computer resolves that there's an antenna present - whether that antenna is working properly or not.  All it does is sense a connection is present.  Unless you or a previous owner beat the snot out of your TAS antenna, and it became physically-damaged (which, by looking at your airplane doesn't seem to be the case), your antenna is not the culprit.  I still advocate for moving the thing to the front of the airplane and using the attached guide as your template.  These antennas are rock-solid.  I've installed three, and doing another on my own Ovation next week.  They are like miniature radars.  Some commercial jets use them (albeit, the NY156 flavor) on their TCAS-II installations, and they simply "just work".  I have yet to see one go bad.
• After what you're saying you've verified above, the most-likely culprits you're seeing are (in this order)...
  • Connections - you have three on this antenna - Sum, Difference, and Probe.  One is BNC, the other two are TNC.  Despite many shops' best intentions, these seem to be where some installations fall short - the crimping and proper connections made to ends that connect to these interfaces.  Making these terminating connections isn't easy...it's a bit of an art.  So in your case, you have six areas (three on the antenna, three on the NGT) where even if one connection is not solid, you will have issues.
  • Type of cable - I suggest (if not already done) using RG142 or RG400 for these wire runs.  Do not make any sharp bends in ANY cable run.  I would remove as much of the older RG58 (if you have it) from your aircraft as you can.
  • Antenna location - Drawings below for reference.

[jamesm]

Curious to know what message are you seeing ? I have had nothing but trouble with mine. I keep getting  "TAS External Fail message"  I have tried switching out the supposedly incorrect RG400 cables going to the NY156  Antenna  with L3 Antenna L-Band Antenna Green cables and the correct antenna connector tray mount. it  still didn't fix my problem.   Jim from L3 was a great help but I believe he has moved on. So I am not sure who we have to reach out to.

James '67C

[Airways]

I’m not getting any messages.  According to the ngt9000, everything is hunky-dory.  But it doesn’t know that there are a ton of acft out there that it’s supposed to report.  I asked the avionics shop to run the TAS check with the ramp test set (this was a couple of weeks ago.  They never reported their findings, but I guess when there is an antenna problem it would have been clear by running this test.  I’ll ask them how this test went…

[StevenL757]

12 hours ago, jamesm said:

Curious to know what message are you seeing ? I have had nothing but trouble with mine. I keep getting  "TAS External Fail message"  I have tried switching out the supposedly incorrect RG400 cables going to the NY156  Antenna  with L3 Antenna L-Band Antenna Green cables and the correct antenna connector tray mount. it  still didn't fix my problem.   Jim from L3 was a great help but I believe he has moved on. So I am not sure who we have to reach out to.

James '67C

1.  Are you sure you have the NY156?  This antenna is certified to the TCAS1 standard, and is $7k - $8k, and the unlock for TCAS 1 on the Lynx is $4k more.  I can't imagine your "C" has this installed.  If you had SkyWatch at one point, or you bought your antenna new, you likely have the NY164.

2.  The "TAS External Fail message" is typically known to be related to something within the computer itself...likely a firmware update needed or (less-likely) the TAS unlock software.  I would contact your avionics shop and have them reach out for support here.

[StevenL757]

11 minutes ago, Airways said:

I’m not getting any messages.  According to the ngt9000, everything is hunky-dory.  But it doesn’t know that there are a ton of acft out there that it’s supposed to report.  I asked the avionics shop to run the TAS check with the ramp test set (this was a couple of weeks ago.  They never reported their findings, but I guess when there is an antenna problem it would have been clear by running this test.  I’ll ask them how this test went…

• Although I'd be curious as to what they report, a ramp test isn't going to simulate the environment in which you claim to be having an issue.  On the ground, you're in a 2D environment.  In the air, it's 3D.
• Unfortunately, when you're troubleshooting an issue such as this, a statement like "it doesn’t know that there are a ton of acft out there that it’s supposed to report" is speculation...not fact.

The only real way you can make a good problem statement is to test in an environment where you KNOW how many aircraft are in a specified area in which you choose to test...and still then, it may not be a 100% accurate test.  Depending on the area, and how you interact with ATC, you might make a request of them...letting them know you're testing equipment and need to know about aircraft in your general area.  The Lynx's TAS function scans for traffic ~35 miles from the aircraft.  If ATC can work with you in an area where there are a few aircraft to provide a good baseline to support your findings, you'd want to record this and then do a sanity check against your claims.  This can help you formulate a better problem statement and help reduce troubleshooting time.  It sounds like a long-shot, but it's worth it.  Don't forget to interpret the symbology correctly on your Lynx front panel...

• Aircraft displayed using the "Lynx Tail" symbology are ADS/B-equipped targets
• All other non-ADS/B targets (Mode-A, C, and S) targets use industry-standard TCAS symbology (diamonds, circles, and squares), although squares are related to TCAS-II resolution advisories (RAs), and won't show up on your Lynx.

[Hank]

"Wheee!! I'm invisible now!"

 

[Marauder]

• Although I'd be curious as to what they report, a ramp test isn't going to simulate the environment in which you claim to be having an issue.  On the ground, you're in a 2D environment.  In the air, it's 3D.
• Unfortunately, when you're troubleshooting an issue such as this, a statement like "it doesn’t know that there are a ton of acft out there that it’s supposed to report" is speculation...not fact.

The only real way you can make a good problem statement is to test in an environment where you KNOW how many aircraft are in a specified area in which you choose to test...and still then, it may not be a 100% accurate test.  Depending on the area, and how you interact with ATC, you might make a request of them...letting them know you're testing equipment and need to know about aircraft in your general area.  The Lynx's TAS function scans for traffic ~35 miles from the aircraft.  If ATC can work with you in an area where there are a few aircraft to provide a good baseline to support your findings, you'd want to record this and then do a sanity check against your claims.  This can help you formulate a better problem statement and help reduce troubleshooting time.  It sounds like a long-shot, but it's worth it.  Don't forget to interpret the symbology correctly on your Lynx front panel...

• Aircraft displayed using the "Lynx Tail" symbology are ADS/B-equipped targets
• All other non-ADS/B targets (Mode-A, C, and S) targets use industry-standard TCAS symbology (diamonds, circles, and squares), although squares are related to TCAS-II resolution advisories (RAs), and won't show up on your Lynx.

I’ll second Stephen’s observations. Having flown behind the Lynx 9000+ for the past 5 years, there is a lot going with the detection and reporting. Everything from shadowing to distance limitations are at play. Another thing that will make planes disappear is whether or not the Lynx mode is set to something that is other than unrestricted.

I fly in an area that is pretty much an ADS-B mandate area. In theory, I should see few TAS targets, but I still see them in mandate areas.

Here is an example. I’m flying into my home airport. The brown target on the ground showed up when I am on final. At the same time an airliner leaving Philly shows up as a TAS. Why would an airline show up as a TAS target? A few moments later, that TAS target showed up as a standard target. Shadowing?




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[Marauder]

I will add one thing. When the ATAS triggers, it has been 100% accurate as to a real risk.


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[jamesm]

8 hours ago, StevenL757 said:

1.  Are you sure you have the NY156?  This antenna is certified to the TCAS1 standard, and is $7k - $8k, and the unlock for TCAS 1 on the Lynx is $4k more.  I can't imagine your "C" has this installed.  If you had SkyWatch at one point, or you bought your antenna new, you likely have the NY164.

2.  The "TAS External Fail message" is typically known to be related to something within the computer itself...likely a firmware update needed or (less-likely) the TAS unlock software.  I would contact your avionics shop and have them reach out for support here.

I appreciate your response.

1) Oh yeah .... I have probably most expensive install of the NGT9000+ in a Mooney. if not the most expensive installation of the NGT9000+ cost just about the same as the GFC500 installation last year.

2) The so called "Avionics Shop" had lied to me, and had never had installed NGT9000+. They had claimed they had when I asked, only discovered after picking up the plane. I had to clean up the "Avionics Shop" wiring mistakes and the person running the "Avionics Shop" is no longer. Yes I have reached out other Avionics Shop  (including one on this form ) but no avail. It just keeps cost me more money.

I have  tried the firm ware update in the past It didn't fix "TAS External Fail message"   message Jim from L3 had help me. So I am orphan customer. regretting my mistake

Thanks

James '67C

[StevenL757]

Where are you located?

[jamesm]

In the cool overcast of the PNW, Renton, WA (KRNT)

[Airways]

Follow-up: apparently the TAS stops working as soon as the NGT gets a GPS-fix.  Strange, huh ?  Shop tries to contact L3 now in order to figure out how to proceed.  Looks like a software issue ?