Dear Fellow Pilot Roaming the Virtual Skies,
    
In case you are wondering what this web site is all about, here are a few notes: 
        
I created this site because I like flying with full ATC coverage from airport A to airport B in airliners. You know, as real as it gets... But even for a short 60 minutes flight, it can be a challenge to get a minimal combination of air traffic controllers together for the full duration of the preparation and flight phase and not end up in Unicom land at some point. There are great visualization tools out there where one can check for such a combination and then selecting an airport combination. But the process can be tiresome...
       
So I built myself an analysis tool that checks twice a minute if ATC is present between two airports with a high likelihood of all controllers being there for at least 2 hours. If my requirements are fulfilled, the route shows up as ‘green’ in the list on the main page. If ATC coverage between two airports is present, but my time requirement of at least 2 hours along the way is not fulfilled, the airport combination is in the ‘orange’ list on the main page. It could still work, but the likelihood that the destination airport tower controller or an area controller for a later part of the flight is still there when I arrive is lower.
       
For me, and that is certainly a personal choice, a minimal combination includes, in most cases, a tower or departure controller at the departure airport and full area control to the destination airport, even if that means it is only just one controller. At the destination airport, I would like to have at least a tower or approach controller present.    
    
Fulfilling these requirements and programmatically checking them is not straight forward for a number of reasons. Most importantly, controllers are usually online for 2 to 2.5h at a time and there is usually little coordination between them. This means that for full route coverage, a controller combination is required, where the departure tower or departure controller is online for less than 75 minutes, the area controller(s) for less than 60 minutes, and the tower controller at the arrival airport for less than 30 minutes. Also, area control between two airports can vary, as airspace is split vertically and horizontally in the VATSIM/IVAO top-down approach depending on the number of controllers and number of pilots flying at a particular time. And finally, there is no data readily available which area controllers are in charge between two airports.
        
So I built myself rules to reflect these requirements and use them for the prediction on this page. The rules are certainly not perfect, controllers come and go at their liking, and I do make exceptions, and still keep changing time requirements when I see that a particular route prediction didn’t work as expected. The rules are certainly not perfect, but work pretty well for me.
        
For comments, questions and suggestions, feel free to drop me an email at 
info at unicom-avoider.org