Greg Esres wrote:

Only GPS with either selectable scaling to 0.3, flight director, or
autoflight coupled to RNAV. DME/DME is not authorized RNP 0.3 except
with special authorization at some locations.

Thank you. In regards to the last, the instrument approach plates
that do not allow RNP 0.3 say "Not Authorized". I assme that every
plate without that IS authorized. Are you saying that the latter is
"special authorization" ?

So far as I know, they all say:

"GPS or RNP 0.3 required. DME/DME RNP 0.3 NA."

And, the first sentence has a bit of "The Emperor has no clothes" in it,
in that it suggests there is some way of getting to RNP 0.3 in addition
to GPS. That comes from the sensor-independent concept of RNP. Trouble
is there is no sensor other than GPS around today that will do RNP 0.3.