I think the clarification from the FAA is recent about DME and ADF
substitution. However, note that if this is an ALTERNATE airport, you
cannot substitute.


More precisely, the substitution cannot be considered when choosing it as an
alternate. No ADF, can't use it as an alternate. Hoever, once in the air,
should you actually require an alternate airport, you are not required to use
the one in the flight plan, and you may use one notated ADF required by
substituting GPS just as if it were your intended airport and approach.

Requirements for filing differ from those for using.

Jose

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