I saw a NOTAM about a VOR being unmonitored. I think this means that the voice capability of the VOR frequency is not in operation/nobody is listening. Is that right? If so, it just seems like something nice to know but doesn't affect the navigational capability of the VOR, right? If a VOR is unmonitored can I still use it for navigation, such as for a VOR/DME approach?
2$\begingroup$ When I took my initial instrument checkride, I was flying the VOR-A for a rural airport, bouncing along, and working at "ATPing" it by keeping the needles inside the donuts. The VOR had been identified, and I was turning final, if one call it that, for the VOR-A. Then I noticed that the ID for the VOR changed, and was "TST" which I recognized readily as I know Morse code. I applied full power and executed the missed, announcing what I was doing on the way. The cranky DPE wanted to know why I did the missed, and I told him the VOR was unreliable. I managed to pass the ride. $\endgroup$– mongoSep 26, 2019 at 13:29
Actually it doesn't have anything to do with voice capabilities:
5-3-5. UNMONITORED NAVAIDs
a. All VOR, VORTAC, and ILS equipment in the NAS have automatic monitoring and shutdown features in the event of malfunction. Unmonitored, as used in this order, means that the personnel responsible for monitoring the facility have lost aural and visual monitoring capabilities and cannot observe the status of the facility. It does not refer to the automatic monitoring feature.
b. When a navigational aid's operational status cannot be monitored at the controlling or monitoring facility, but all indications or reports are the facility is operating normally, issue a NOTAM placing the aid in an unmonitored status.
c. When issuing a NOTAM describing a facility as unmonitored, do not use the category of monitor, only the contraction UNMON.
!DCA LDN NAV VOR UNMON
(Source: JO 7930.2M)
So basically it says that this VOR may malfunction without notifying a responsible party, or that a responsible party is no longer monitoring the VOR. A lot of times this is done with VOR's that are scheduled to be removed from service, they may be allowed to continue to operate but are no longer maintained.
You can still use the VOR for navigational purposes. The VOR is supposed to shut down in the event that it becomes unusable, so you can be (relatively) assured that if the VOR is operating, it is reliable and usable.
$\begingroup$ Of course, if the airport authorities aren't doing their job properly, the automatic monitoring feature can also fail. $\endgroup$– VikkiMay 16, 2021 at 21:10