ADSB visibility with non certified GPS

On Thursday, September 21, 2017 at 7:31:32 PM UTC-7, Darryl Ramm wrote:
Walt, I think you are misunderstanding what Trig wrote. A TN72 GPS Source will be seen by everybody. That is why anybody doing ADS-B Out in an experimental glider with a TT22 should be equipping with at least a TN72 (or TN70, TN70 required for certified gliders).

Darryl,

OK, I'm clear now that a TN72 GPS Source from a Trig T22 will make me officially visible to all ADS-B in equipped aircraft.

I am still trying to figure out why I would want to equip with any kind of ADS-B out in my T22 equipped glider:

1) It would be great (but not necessary) to be seen by all ADS-B equipped aircraft. But, with ADS-R (rebroadcast) won't those other aircraft see me anyway since I'm equipped with a Mode-S Trig transponder? I suppose at low altitude where ADS-R is not available, direct receipt of my ADS-B out would be an advantage.

2) It sounds like with the TN72 GPS source, I will not be compliant if wanting to enter Class B, C, and a few other little used airspace. My question is this... If equipped with a TN72 GPS source, do you think that ATC will allow temporary access to Class B and C... such a for passing through their airspace? That was ONE reason for equipping with a transponder in the past.. I have no intention of OPERATING in Class B and C so as to use full ATC services. Also, do you think that controllers for restricted airspace MIGHT allow transiting that airspace without fully compliant ADS-B out?

If ATC uniformly will disallow temporary transiting of Class B, C and restricted airspace unless equipping with a fully compliant GPS source (i.e. TN70), then there is VERY LITTLE REASON TO EQUIP WITH A TN72.

I see small potential justification for equipping with a TN72:

A) visibility to all ADS-B official aircraft directly without rebroadcast (ADS-R) which means they can see me in the pattern a low altitude.

B) Potenially, a TN72 will also give me an alternative to a Satellite tracker if Flight Aware or Aerion makes tracking of ADS-B aircraft less expensive than the current vendors (Spot and Garmin Inreach).

comments...

Walt Rogers WX