It is legal to legal to fly IFR as long as the required equipment is
on board, and the pilot is appropriately rated, and current, etc.,
etc., etc.

It is illegal to fly IFR =without= the required equipment on board.

It is illegal to fly IFR with only a tuna sandwich for navigation.

If you =do= have the required navigation equipment on board (which
generally means VOR, GPS, and/or INS), you may consult the tuna sandwich
all you want.

End of problem.

Jose
--
Nothing is more powerful than a commercial interest.
for Email, make the obvious change in the address.