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Old April 20th 05, 12:47 AM
Patrick Dirks
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In article ,
Roy Smith wrote:

Paul Folbrecht wrote:
I really still wonder about the whole thing and marvel at the fact that
they'll expect me to navigate under IFR with this thing without a
current database (I don't keep the DB current and there's certainly no
reason at all they should expect that I do).


Controllers are not pilots (some are, but it's not a requirement and most
are not), and don't understand the nuances of things like GPS database
currency. Putting "VFR GPS" in the remarks, while having no official legal
significance, says to the controller, "I want to be given direct
clearances". You ask for them, he'll give then to you. Then it's up to
you to decide if you can safely execute them. If you can't, say, "unable",
and he'll come up with a different clearance.


FWIW it has been my understanding that ATC cannot legally assign you
"direct" to some fix you cannot navigate to using the equipment suffix
you've filed with; if you file /U or /A you can't be expected to
navigate directly to a fix not defined by VORs.

Of course it is YOUR responsibility to figure out what you can navigate
to, and to tell ATC you're "unable" if ATC tries to clear you somewhere
that would require use of a GPS; a VFR hand-held GPS is irrelevant as
far as "official" navigation is concerned.

That said, I've also understood that adding "VFR GPS" in the remarks
might encourage ATC to give assign you a HEADING somewhere, maybe with
"direct when able" or something, on the assumption that with the aid of
your VFR GPS you'll be able to head somewhere with surprising accuracy,
which helps everyone.

You could also ask for "Radar vectors" to somewhere, perhaps as in
"request heading 242 degrees, radar vectors FUBAR"; with "VFR GPS" in
the remarks ATC might go along, assuming you'll end up making a nice
beeline for FUBAR. Officially you're on Radar Vectors and ATC retains
responsibility for you; in practice you're no added trouble because you
can head somewhere better than without your "VFR GPS" on board.

That's the reason I've always understood for "VFR GPS ON BOARD" and why
I occasionally specify it filing IFR.

Cheers,
-Patrick.