Darryl,

I found your fourth paragraph very confusing:

ADS-B data-out in gliders will not provide an airliner with an RA from
its TCAS II system - something many pilots are not aware of. TCAS
needs a transponder to interrogate to issue an RA. The whole topic
does not get talked about much because it is implicitly assumed that
threat aircraft have transponders or transponders *and* ADS-B data-
out. If your airline has fitted a modern TCAS II that includes ADS-B
data-in and CDTI then you will get traffic display of ADS-B data-out
equipped aircraft but no RA. And you may even have have TCAS II with
ADS-B data-in for TCAS "enhanced surveillance" but still no CDTI/ADS-B
data-in display of traffic at all.

Are you making an assumption here that the glider in the first
sentence is flying in the US and has a UAT setup to yield ADS-B data-
out? Because in Europe I'm almost positive that ADS-B out can only
achieved with 1090ES, which of course will indeed provide a RA from a
TCAS system.

-John