This may have been asked before, so forgive me if this is a repost.What happens if you are flying into an airport (or even controlled airspace for that matter), switch over to the tower/center frequency, but nobody is "working" that frequency? Is this a problem? To be sure, there isn't some one for every single towered airport. What happens if you call the tower (or center) and no one responds? Do you go a UNICOM frequency and start using text?Haven't gotten on VATSIM yet, hope to in the near future though. Just want to get some questions answered so I know what to expect when I do connect.Thanks!- Jason

Hi Jason,Wherever you are flying, you can access a list of the controllers active in your area. VATSIM works a top-down system where if there's no aerodrome control on, the approach controller will do Towers job, and if there's no approach controller, the centre controller will do it, unless he's too busy. If there's absolutely no-one covering an airport, then you do everything on unicom freq 122.800. This has to be by text, as the server set-up for unicom has problems with voice (long explanation omitted here).The answers to this and many other questions are in the Pilot Resource Centre at www.vatsim.net/prcRuthVATGOV7Vice president - communications, VATSIM