Mike,

According to the AOPA Air Safety Foundation safety advisor titled "GPS
Technology" you can use GPS for DME with a couple of exceptions. You
can use GPS in lieu of DME if the named fix appears in the
GPS database or if the datum upon which the fix is
based is in the GPS database. In other words, if you
were flying a VOR-DME approach without DME
aboard, the GPS can substitute if the required fixes
are named and included in the GPS database or if the
VOR upon which the approach is based can be found
in the GPS database.

Read the document, it is really good.
http://www.aopa.org/asf/publications/sa01.pdf

Mike Salzman
LNCE 75%
Fairfield, CA
arrow54t@yahoo.com


 
--- "Mike S. Reinath" <Michael.S.Reinath@nasa.gov> wrote:
>
> It seems fairly clear that I can substitute GPS for DME during the en
>
> route and terminal phase of the flight. Where I am unclear is for the
>
> approach.