Non existent VOR

Steven Barnes wrote:

I'm late in joining this thread, but on an Angel Flight a year or so ago, I
was happily moving along my IFR flight plan following airways when IND
approach told my the Hoosier VOR was OTS. I was never told that during my
briefing. 3 seconds after an "uhh... stand by" on my part, IND offered
vector direct to my next VOR. Duh. D - next waypoint & we're off. Actually
shaved a few minutes off, anyway.
It did kind of surprise me, though.

I've also seen (on an Angel flight, coincidentally) that I knew from NOTAMs that
a VOR was scheduled to go OTS for maintenance during my flight, and should go
out of service about the time I got to it. I was surprised to find I received
the identifier, and queried ATC - was the VOR operational or not? They had no
clue. Shortly after that the identifier stopped, and I informed ATC I would be
out of navaid range for a few minutes and requested they monitor my track, which
they agreed to do.

Curiosity question for ATCers: how do you find out about inop navaids?

Dave