On Tuesday, February 10, 2015 at 8:17:50 PM UTC-8, Bill T wrote:
Most GPS units in gliders may be WAAS compliant, but with the previous language they were not approved to provide adsb out because they do not have the TSO Certification.
BillT

It appears in the new rules that it only has to meet the performance requirements. Furthermore the wording would suggest it is up to the installer to decide that it does until the FAA indicates otherwise? Which is reversed from TSO. Almost any GPS engine is WAAS compliant now. But I don't know what else is involved in meeting the 'performance requirement'. It seems like there is hope though, given that the spec was written while vacuum tubes were still in common use.

I'm sure Darryl will jump in at any moment and set me straight.