Controlling is entirely volunteer based. While controllers may have an idea of how long they'll be on, things change, and they may not control at all when they were planning on doing so. It's unrealistic to force controllers to sign up for controlling, however many ARTCC's have timetables or calendars that controllers can use to indicate when they will be online. As well, many controllers will include an estimated time in their controller ATIS indicating when they are planning on logging off. Of course, if you fly for an event, controllers will be on for the entire advertised time, and often for another hour or longer later.

As far as controlling local positions, controllers are required to undergo a series of training sessions and exams to move up. You start with GND/DEL, move up to TWR, then APP, and finally CTR. It often takes upwards of a year for a student to go from an Observer to a Center controller. Programs such as VATSpy show the VATSIM ratings (S1, S2, S3, C1, C3, I1, I3, SUP, ADM), although this may not correspond to the controllers certifications within their facility. As an example, I am a visiting controller at New York (ZNY). While I hold an I3 rating (and control at ZNY as a C1, a controller or center rating), I am only certed for approach at one facility and departure at another. This means that the HIGHEST position I can work is NY_ARD_APP (approach for Newark Area), and I cannot contorl anywhere at PHL, not even Ground. A roster, including what positions different controllers are certified for, can be found on ARTCC websites.

Hope this helps clarify things.

I am a big supported of using the Contact Me feature.  I dont care what the COC says.  Why do people get online?  Either they want to fly in a simulated environment (meaning they want to be controlled) or they want to control aircraft.  I know that it can be argued that there are maps etc. that tell you when to contact ATC etc.  There is no simulator that I am aware of that will tell you who's airspace you are in when you are flying.  Everybody wants to talk about the real world this and the real world that.  In the real world an enroute controller would hand you off to the next facility, since we can not guarantee who will be on and who will not, this is not an area of realism that we can accurately simulate.

My thinking is if you want to control that aircraft, send a contact me.  On the flip side, I have had controllers who never contacted me and they were not online when I entered there airspace and when I realized that they were online and contacted them, i got an attitude; my thoughts STICK IT!!!  If you wanted to control me, then you should have contacted me and let me know you were online.  If a pilot does contact you before you contact him than Wooooo Hoooooo.  We are supposed to work together to have fun and make this hobby fun.  I applaud you for sending the contact me, if you do it again, I will applaud you again and if a pilot gives you any flack, give him a .wallop

Agreed. As well, many programs such as VATSpy only show part of the airspace, sometimes committing important shelves, such as the one shared by ZBW and ZDC at or above FL240. Anyone looking at VATSpy who does not understand the airspace would wonder why they are not contacting New York Center, and indeed I've had many pilots who disregard the frequency I give and do just that.

IMO, if you want to talk to a pilot, send a contactme. Send it at the location where you would normally receive a handoff, radar identify the aircraft, and bring them in. I will add that I have seen an over-reliance on contactme's that can lead to issues. Earlier today, I had an aircraft depart an untowered field. They were filed IFR to a towered, class B airport in my airspace, however I was online before they departed, so I assumed they were proceeding VFR because they did not call me. Eventually, the aircraft overflew the airport by a significant amount, was actually into another ARTCC's airspace, and called saying he never received a contactme. Pilots also need to be aware who's online, especially if they're departing untowered ops and remaining in Class E airspace, where they are not required to contact a controller if VFR.

Congrats Nick!

Congrats Tanner!