On Wednesday, March 28, 2018 at 7:33:29 AM UTC-7, son_of_flubber wrote:
On Wednesday, March 28, 2018 at 10:09:50 AM UTC-4, wrote:

The 2017 (and previous) Spruce catalog says the TT21 is for sport aircraft, meets the standards, etc. Now in the 2018 catalog they added in bold print "DOES NOT MEET USA STANDARDS."

Don't jump to conclusions. You're overlooking a lot of relevant information. Read some of the more recent RAS threads about ADSB TABS Trig etc..

The TT21 implementing TABS looks just like ADSB-Out to ATC and any plane running ADSB-in and so it works just fine for many glider pilots, maybe not everywhere for all glider pilots... it depends.

Don't ask for clarification in this old thread. Go read the more recent threads first.

Yes, this has been discussed in detail on r.a.s. for a few years now and I'd hope was old news.

Just one point: TABS per-se is likely not visible to ATC, it is not in current deployments of ATC approach/TRACON systems I'm aware of and it's best to assume its not visible. This is at least consistent with the idea that TABS does not give ADS-B Out required airspace privileges. And on the flip side, a TT21 or TT22 transponder with a TN72 TABS GPS Source added to it *is* visible to ATC within plain old SSR coverage... thats still not going to help for any ADS-B Out required airspace flight after January 1, 2020 (Which for gliders with the partial exemption is: Class A, B, C, and above B, and C up to 10,000').