By Adam Bartlam 1267520
#539267 Hi!

I'm a member of a leading VA in the UK. I would ideally like to open a short dialogue with the developer of vPilot if possible to ask about a specific situation we're trying to resolve in the VA.

The VA uses several franchises who currently run all under the same callsign prefix. We have our own set of model matching rules so that our aircraft liveries are correctly depicted by vPilot. This is fine where an airframe is used only by ONE franchise. For example, lets say that the VA's callsign prefix is ABC and there are two franchises, X and Y. If the 738 is ONLY used by franchise X, then the matching rule is fine as follows:

Code: Select all<ModelMatchRule CallsignPrefix="ABC" TypeCode="B738" ModelName="738_Model" />

Because ALL 738s with the ABC prefix will always be the same livery (franchise X) this works fine.

However, some airframes are used across both franchises. So for example, if BOTH franchise X and franchise Y use the 777-200LR (each with their own livery) this causes a problem:

Code: Select all<ModelMatchRule CallsignPrefix="ABC" TypeCode="B77L" ModelName="772_Franchise_X" />
<ModelMatchRule CallsignPrefix="ABC" TypeCode="B77L" ModelName="772_Franchise_Y" />

We have been able to work around this to a certain extent because the flight numbers used by the respective franchises fall into different ranges, giving:

Code: Select all<ModelMatchRule CallsignPrefix="ABC" FlightNumberRange="0-499" TypeCode="B77L" ModelName="772_Franchise_X" />
<ModelMatchRule CallsignPrefix="ABC" FlightNumberRange="500-999" TypeCode="B77L" ModelName="772_Franchise_Y" />

So far, so good. Now... this is where we have the issue... sometimes there is more than one member wishing to fly the same flight online or we hold an online event for the VA where everybody on the event would be flying the same flight. At this point, we need to differentiate between the flight numbers used on VATSIM in order to connect and also so that communication is clear with flight numbers which aren't all too similar. Ideally we would use alpha numeric flight numbers. However, these would then not fit into a numbered range as required for the model matching rules (VMR) which would allow the correct livery to be depicted.

Historically, we have gotten around this by using our own none ICAO type codes (e.g. B77X and B77Y), but we have dropped this policy as clearly that may be less than ideal for users of VATSIM who do not have our models and rules installed.

My question is this: Is it possible to use alpha numeric flight number ranges? If so, how does that work? If not, would it be possible to add this feature in a new build at some point? From a development point of view it would work for us if prior to processing the flight number vPilot simply removed any alpha characters and THEN checked it as previous in flight ranges.

Apologies for the LONG post, but I wanted to explain clearly what we were trying to resolve and what we'd already done. We already understand that one solution would be to use different prefixes for the different franchises, but we are trying to avoid that so that it is easy for controllers to see and recognise our already well known callsign.

Any suggestions / solutions are much appreciated.

Kind Regards

By Adam Bartlam 1267520
#539383 Hi Ross

Thank you for your response.

Ideally if we had callsigns in the format of ABC12NM where ABC was the 'CallsignPrefix', we could then use the two numbers as an identifier for our franchise as a 'FlightNumberRange' and the final 2 letters would be used in the callsign to allow for avoidance of 'callsign confusion' in radio communication... but could be ignored for the purposes of callsign processing in the VMR file.

For example, ALL franchise X callsigns would be ABC10AB to ABC19ZY. ALL franchise Y callsigns would be ABC20AB to ABC21ZY. To process this, vPilot would just need to strip any letters from the end of the callsign before processing it as it currently does with numeric callsign ranges, as it would still be the number range which identifies the franchise.

The difference this would make would be on air, currently, three VA pilots flying together might be ABC4356, ABC4357 and ABC4358. This makes communication confusing for pilots and controllers with the similarities. Adding Alpha characters helps differentiate between callsigns, e.g. ABC43Alpha-Bravo, ABC43Charlie-Whiskey and ABC43Foxtrot-Juliet all sound very different.

Hope that makes sense!

Kind regards

By Ross Carlson 887155
#539388 Do you actually have so many franchises that you need two letters to denote the franchise? (Meaning 26 x 26 or 676 combinations?)

vPilot already allows for a single letter suffix as is often used in the real world. Would that be enough?
By Adam Bartlam 1267520
#539426 Hi Ross

Thanks for the information. I wasn't aware that a single letter suffix could be used - that is good to know. I assume this would give a callsign in the format of ABC1234A? Or is it ABC123A? Would it still work for ABC12A?

And no - we don't have that many franchises. The issue wasn't being able to find enough different combinations for the franchises, but rather that when two franchises used the same airframe the only way to differentiate between them for correct model matching was to use the FlightNumberRange attribute in the VMR file (as CallsignPrefix and TypeCode would be the same for both franchises). This worked fine. However, especially when events were on, it lead to many very similar callsigns being used which isn't good for radio communication. Using the alpha characters allowed for much more different sounding callsigns on air as per the example in my last reply.

One is certainly better than none and I wasn't aware that was a possibility - so thanks again for the info. Ideally we'd like two, as this would allow members to include their initials, but I appreciate that would mean work on your side on what is already an awesome piece of software.


By Ross Carlson 887155
Adam Bartlam 1267520 wrote:I assume this would give a callsign in the format of ABC1234A? Or is it ABC123A? Would it still work for ABC12A?

All of the above would work ... any number of digits is allowed.