On Tuesday, December 12, 2017 at 2:16:03 PM UTC-8, Darryl Ramm wrote:
...and more than that, I have the Mode C veil stuff wrong as well, thanks for David Anisman for reminding me of past FAA interpretation letters, clearly I made a mistake trying offer a quick hit at airspace stuff while talking about ADS-B. I've updated that post again :-(

I'll write up a separate post trying to get all the airspace stuff properly explained. It deserves some careful writing all in in one place. And I may get a letter off to the FAA to reconfirm again for ADS-B. But the big thing is previous FAA legal interpretation support you can be above any airspace (including within a Mode C veil) at 10,000' in a glider without a transponder and that interpretation should carry over to ADS-B Out after 2020. You can't be below 10,000' and above Class C airspace, that is one that catches some into needing full 2020 ADS-B Out requirements, another is obviously the big dogs who want to fly in Class A airspace after 2020.

No of course I'd hope pilots flying anywhere in or near a Mode C veil would voluntarily equip with transponders and increasingly with ADS-B out. The nice thing is TABS allows you to do that voluntarily at lower cost that full 2020 ADS-B compliance, including using a Trig TT21 transponder (without upgrading it to a TT22) and a TN72 $350 GPS.

My headache is back.

So, now I can have an ADS-B compliant system using my TT21? When did that change?

Tom