What exactly does that mean?
It sounds like the TAS605 will continue to work as it does at present (“via the active interrogation of the aircraft transponder”) but the KMD550 will not display aircraft which are only ADS-B OUT and not Mode C (or the Mode C is out of range).
Can you confirm, @AviSimpson?
If I am correct, which display products would display ADS-B OUT aircraft?
I would have expected the upgraded TAS605 to merge both Mode C and ADS-B aircraft into the same data stream going to the KMD550. Why should that not work?
The TAS as it is today will display all aircraft that have transponders (Mode A, C, S, ES). TAS-A will merge those same aircraft with the ADS-B stream that compliant ADS-B aircraft are broadcasting. This prevents any duplication of traffic targets and is required for an ATAS product like TAS-A.
The mention of ARINC429 which is what we use to display TAS targets today. You will still see targets via 429 however, the symbology of those targets will be the same diamond and threat bubbles visible today. ADS-B symbology, directional targets, is only available using RS232.
Thank you again, @avisimpson
You will still see targets via 429 however, the symbology of those targets will be the same diamond and threat bubbles visible today
So with the KMD550 I will still see the ADS-B traffic.
directional targets, is only available using RS232.
Which display products would display the ADS-B OUT aircraft using directional symbology?
I do understand that the data stream you run over the RS232 interface carries more information than the ARINC429 TIS data stream does.
For example further back up this thread there was the Avidyne Cessna TTX which showed tail numbers (of N-reg aircraft only), but I wonder how it acquired those since this was about 10 years ago. It must have been picking up Mode S, which AFAICS the TAS605 doesn’t use for anything. Are you able to illuminate this aspect?
A final Q which popped up further back in this thread: does the ADS-B IN TAS605 upgrade require any other upgrade in the aircraft? For example there was a concern that it would require a certified ADS-B OUT at the same time, via an upgraded GTX330 and a “W” GPS.
You will see ADS-B targets on your KMD550 via 429.
Peter wrote:
For example further back up this thread there was the Avidyne Cessna TTX which showed tail numbers (of N-reg aircraft only), but I wonder how it acquired those since this was about 10 years ago. It must have been picking up Mode S, which AFAICS the TAS605 doesn’t use for anything. Are you able to illuminate this aspect?
A final Q which popped up further back in this thread: does the ADS-B IN TAS605 upgrade require any other upgrade in the aircraft? For example there was a concern that it would require a certified ADS-B OUT at the same time, via an upgraded GTX330 and a “W” GPS.
The only additional item that is required is an ADS-B compliant GPS position source.
So, the Avidyne TAS6xx ADS-B IN upgrade requires ADS-B OUT at the same time.
That’s another major avionics upgrade… A good job I asked the question.
Just been reading this document which shows that there might be a push to get more GA aircraft transmitting ADS-B Out. What I like is the fact that they are looking to force people like (e.g.) Garmin to accept non certified GPS sources to act as the Location source for their GTX330-ES….
Interesting document Steve. Local copy. Some interesting quotes:
It is puzzling why ETSO-C166b-compliant transponders should be excluded?
There is consistent anecdotal evidence that certified avionics engineers are
reluctant to install and configure connection to non-certified GPS devices even
when the installation meets the above requirements
The NATS report, published 21st December 2015, following NATS/CAA sponsored GA
Non-Certified GPS ADS-B Trial highlighted the fact that non-certified GPS ADS-B
presented just as accurate position information as certified GPS ADS-B. So, policies
that prevent/do not encourage the use of non-certified GPS ADS-B do not improve
safety; they reduce safet
I still see a problem with certified (active) TAS boxes not displaying any of the proposed solutions. I know that can be regarded by some as an “elitist” comment but nobody ever made money by screwing the top of the food chain 
And in GA one tends to find that the “top gear” stuff moves down the food chain over time. Plus most people will not fly with some velcroed gizmo with a wire running down to the cigar lighter…
Peter wrote:
I still see a problem with certified (active) TAS boxes not displaying any of the proposed solutions.
TAS boxes are active devices and query transponders on 1030 MHz with a mode C query. They have nothing to do with ADS-B and should display targets that reply with a mode C or mode S response on 1090 MHz. It matters not a whit if the transponder is ADS-B Out compliant or not. SIL is irrelevant as is the software version of the ES transponder. In the US, the second ADS-B frequency is not based on transponder technology so one must keep the transponder to support TAS/TCAS inquiry as well as secondary radar systems which don’t process ADS-B broadcasts on either frequency.
Sorry; I was referring to ADS-B IN capability in the certified TAS boxes e.g. the Garmin one or the Avidyne one. The latter’s ADS-B IN upgrade is vapourware, as described further above. Quite a lot of new-ish planes have these installed and they display only certified ADS-B OUT aircraft.
They do display Mode A/C targets (with some extra functionality in the Avidyne one, subject to limitations I have been unable to establish, derived from Mode S) but ADS-B would work more reliably and more accurately.
Peter wrote:
They do display Mode A/C targets (with some extra functionality in the Avidyne one, subject to limitations I have been unable to establish, derived from Mode S) but ADS-B would work more reliably and more accurately.
The TAS units have to interrogate Mode S. It is spelled out in the TSO. The Avidyne units will decode the N number from the ICAO aircraft ID, but not other registries, so they must not decode the Flight ID which is also usually set to the N number or aircraft registration or call sign.
