I've been thinking of something that would be a simple, yet elegant solution. I'm hardly a computer programmer to know how easy this would be, but it doesn't seem like it would be bad. Here's my thought:
Have 2 methods of fueling that can be specified based on the aircraft. I'm thinking on the order of a 1 or 0 entered wherever the aircraft specifics are stored for GSX.
In the first state, fueling works like it currently does opening the window and asking you to enter your fuel. In theory, this works well for the default/simple freeware crew.
In the second state, the fueling simulation assumes the aircraft is starting at 10-15% total fuel. The exact number isn't important, but the concept is that the aircraft was brought to the gate with FAR reserve +/- some holding fuel that wasn't used in the last flight. For all intensive purposes you could even assume empty fuel, but it would be more realistic to assume the last crew left some gas in the bird at the end of their flight. The GSX fueling can then look at the fuel currently loaded in the aircraft in FSX (while PMDG style addons may need fuel loads set external to FSX, they all seem to correctly indicate fuel load in the FSX payload menu) and the GSX truck spends X amount of time to "fill" from the 10%ish mark to your loaded fuel state (obviously without actually adding fuel). This would alleviate the need to open the FSX fuel dialogue menu, but would still create some "fuel load" for GSX to fill giving some X amount of time the truck would stick around.
With the if/then statements (or whatever is needed in the C++/xml code) as a base, this becomes a simple 0 or 1 to define which method is used for an aircraft and should be easiy to change to suit specific aircraft. Just my thoughts, but seems like one of these two options would please most everyone.
