Robert M. Gary wrote:


Word games aside, Steven is right. The difference between being IFR and
VFR in controlled airspace is being told "cleared to foobar".

-Robert


The system is designed to process a formally filed IFR flight plan from
one airport to another. The formal tower-en route program in Southern
California works, too, because it is formalized.

Pop-ups without a filed flight plan, and local training flights
sometimes get mishandled because, unlike the foregoing, they just aren't
in the "system" in a formal sense.