"Peter Clark" wrote in message
...

AIM para 1-1-19.f.1.(b)(6):

"Charted requirements for ADF and/or DME can be met using the GPS system,
except for use as the principal instrument approach navigation source.

What serves as the principal instrument approach navigation source for the
ILS/DME RWY 2 at DRO? What serves as the principal instrument approach
navigation source for the VOR/DME RWY 15 at MTN?


OK, using that as a baseline then GPS wouldn't be a permissible
substitute for DME in any approach using a DME arc, so why would it be
documented in the manuals if it's not permissible?


You didn't answer the questions. We can proceed only after you answer the
questions.