More efficient vehicle usage:
I can’t imagine that this hasn’t been addressed yet, but I can’t find anything about it, so I’ll leave it here:
I’ve seen many vehicles driving to an airplane, dropping off a little bit of fuel, only to be empty before the plane is completely fueled, or collecting a bit of garbage, only to be full before the aircraft is empty. This makes it so that delays are unavoidable at some points in time. Sure, if the fuel truck just fueled another plane on the stand right next to it, it can dump its remaining fuel in this plane, but if it’s coming from a parking spot, it should always make sure it has enough fuel to completely fill the aircraft. Same goes for the garbage collection trucks. If they just cleaned the plane nextdoor, feel free to come over and use whatever capacity you have, but it shouldn’t come over to the stand from the parking where it was for the past 8 hours, when it’s nearly full, that just doesn’t make sense.
In addition to that, I think it would make a lot of sense for trucks to permanently park at their respective buildings. Catering trucks park at the catering depot, garbage trucks park at the waste depot, and fuel trucks park at the fuel depot. Sure, you should be able to still use parking spots or general vehicle depots if you want to, but the specific depots (catering, waste, fuel) should at least have a few parking spots. That way, each time a vehicle parks up, it can be emptied / filled so it’s ready for its next job.
Why it should be implemented:
Currently, the logic just doesn’t make sense. Nobody in their right mind would drive up to an A380 with a 10 liter fuel can, thinking “that should do it”, just to have to drive all the way back to the depot, fill up, and go back with more fuel. Improving this should be easy, and would make the vehicles’ behavior a lot more predictable and reliable, plus it would prevent random delays.