On Thursday, December 17, 2015 at 9:49:30 PM UTC-8, Mike Schumann wrote:
On Thursday, December 17, 2015 at 11:46:45 AM UTC-6, Andrew Ainslie wrote:
Apparently it can't just be any non TSO'ed GPS to be fully compliant. A few months ago the FAA opened up a new category whereby "equivalent" units could be used in Experimental, and this device of Garmin's is the first to fit this new niche. Hopefully others are following, including Trig. But agreed, it's ridiculous that we can't just use on of the other GPS's floating around our cockpits to give the TT22 the required information. Anything WAAS (hell, actually anything at all) is way better than either radar or nothing at all. Part of the frustration is that without ADS-B we get no input. It would be so nice to know where the power guys with mode C are relative to us. The FAA definitely needs someone like JC to explain why their strategy of "forcing" us to get ADS-B out in order to get in is deeply flawed, and the requirements to either spend over $3000 or be blind is equally dumb... But that ain't going to happen. In the interim, I'm going to keep hoping that a reasonable solution shows up.

There is an intermediate solution whereby you can hook up a non compliant unit but if you properly declare the signal, I don't think you get ADSB in but I don't recall the exact details. I'd prefer full compliance but I think it might be time to play with that option over winter.

The next problem, of course, is to get a transponder shop to help you get anything done. They are very leery of helping with experimental planes and non TSO'd options. My local guy just told me that he'd no longer do my transponder certification, even though the TT22 is a TSO'd unit and he installed it a year ago - he claims the FAA does not allow him to work on experimental. Sounds like baloney but not much I can do about it if he doesn't want to do the work.

Gliders are currently exempt from the 2020 ADS-B rules. As a result, you should be able to use a non-compliant GPS source with a Trig21 or Trig22, as long as the Trig is compatible with the GPS's datastream. Even though the GPS source is non-compliant, it will trigger the ADS-B ground stations so that you will get TIS-B and ADS-R transmissions.

This is what the Dynon Skyview systems do today. According to Dynon, this will continue to work after 2020 if you are flying in airspace where ADS-B is not required.

I expect that we will see affordable 2020 compliant GPS sources in the relatively near future. The Dynon units, which are suppose to start shipping by the end of this year, have set a pretty aggressive price point (under $600). While the Dynon module only works with the Skyview system, I was talking to an engineer at Trig a couple of months ago, who told me that they were planning to introduce an affordable compliant GPS source at a similar price point shortly after the Dynon units start shipping.

One thing that you should think about if you want to be fully 2020 compliant is that you buy a Trig21, NOT a Trig22 transponder. The Trig22, while it is ADS-B OUT compatible and will trigger the ADS-B ground stations, is NOT 2020 compliant.

Other way around isn't it? Trig 22 has legal power, Trig 21 does not? What happened to all the noise around the FAA survey and a lower cost alternative (forget the name of it)? That is the place to push for Trig21 and Flarm GPS.