Thing is if the path isnt a straight line then you add more nodes and make the game slightly wobble (so it's not instant turns) but knowing the distances and angles between two coordinates would also allow you to figure out this wobble and include it in the time delay calculation, so you can achieve calculating the arrival time trough a path of nodes using their distances between each other.
For now my problem is that the paths have mapId relative coordinates so I have to figure out how big let's say northrend is, then outlands, e.g. Looking at MapDataLib for some info but havent gotten a proper formula, yet.
Anyway, there are advantages to calculating the times liek this, for once you can get all times without having to fly yourself to "time" it.
*Edit*
Saw your post SDPhantom, thanks. Gonna work it in, hehe. Yeah, I'm a bit unclear about the formulas, hence they look messy.
The coordinates in the DBC are raw, but not sure if it maters the size of the map, I guess not as long we dont fly across one map to the other (like to azuremyst but thats another problem to figure later on, hehe).