Originally Posted by
Kiwi Flyer
I don't know how it works in OW but in *A it is the nonstop distance only if a fare is filed for that route, otherwise it is the shortest filed routing.
You are probably correct, it appears to be the same for oneworld. It's not specific in the
"Rules" but is specified in the
"Planning your Trip" section of the
Global Explorer information page:
If you choose to travel by surface transport between two airports, the most direct flown distance between the origin and destination point of the surface sector will be counted towards your total flown mileage.
It is probably an "IATA" thing.