Well said. I’d also like to add a few other considerations which may not necessarily all apply to the US but seeing as this might become a global thing if the trial succeeds they are nevertheless important to think about.
What do we do about airports where there is no usable real world frequency? There are many military airfields that exclusively use UHF frequencies which, as far as I know, AfV is not capable of (and even if it is, most sims and aircraft have no UHF capability).
How do we deal with airports where charts direct VFR and IFR traffic to different frequencies? For example, here in Germany, there are two airfields (EDDH and EDDS) which have separate Tower positions for VFR traffic (which would deal with all VFR traffic that’s not directly in the circuit or on the runway system), so VFR charts will tell VFR pilots to call on frequency A and IFR pilots on frequency B.
What can pilots do if the chart material they have doesn’t give them enough information to figure out which frequency to use (which can happen especially in places where the AIP or at least parts of it are not publicly and/or freely available)? I mean, we can of course simply say “well, then you can’t fly there, choose another airport”, but there are many cases where one can find enough information to be reasonably compliant with the CoC today but may not be able to remain compliant if the rules regarding unicom are changed globally.
The answer to all of these would be to have a central database where all these frequencies are listed and pilots can easily find which frequency is used as an advisory frequency here on VATSIM when there’s no ATC coverage. The VATSIM AIP can fulfill that role, but it would require that there actually is information on every airfield in the entire world and currently we are very, very far away from that, so facility engineers would face a lot of work to implement every single airfield in their AoR before such a change can take place. It is also problematic in two other ways: firstly, it would require a lot of maintenance as frequency changes are not too common if you have hundreds, maybe thousands of airfields to look at and these changes may not always be well communicated by the responsible authorities, so every AIRAC, facility engineers would have to tediously go through every single airfield to see if there was a frequency change (otherwise, we’d end up with a situation where charts may say one thing and the VATSIM AIP another, potentially putting people on different frequencies without any one of them doing anything wrong); secondly, there are many airfields around the world without an ICAO- or otherwise official code and I don’t think the VATSIM AIP currently allows for full name entries in that way. Additionally, I don’t like the idea of adding another required window/tab for flying on VATSIM, although I could see a potential solution to this particular point in simply adding a new command along the lines of .ctaf ICAO to pilot clients that people can use in lieu of the VATSIM AIP.
Ultimately, I think the easiest way would be to have people use the published advisory frequency at uncontrolled airfields and 122.800 (or some other, globally uniform frequency) at controlled ones. The only problem that would arise with this solution would be HX fields - most places already treat those as H24 on VATSIM and I don’t think there are any that require their controllers to simulate real world operating hours, but some at least allow their controllers to do so if they wish. If VATSIM took a clear stance on this point, any potential confusion would be ruled out with those as well: if HX fields are to be treated as H24 everywhere on VATSIM, then people have to always use 122.800 as an advisory frequency - if HX fields’ operating hours are to be simulated everywhere on VATSIM, then people have to use 122.800 during operating hours and the CTAF outside of operating hours; although I think treating them as H24 is the much easier solution.
It would also have the added benefit of keeping it simple for the more casual users who mostly fly jetliners at bigger airports while also allowing the people who fly a lot of GA aircraft at smaller uncontrolled fields who are usually the people that enjoy a very high level of realism and are more likely to actually know whether a field is controlled or not to realistically simulate the use of advisory frequencies at those fields.