As you may know, AE currently estimates an aircraft's range with full payload using its absolute max range. This has led to sizable discrepancies for some aircraft, such that their max payload range in AE greatly exceeds that in real life, thus allowing those planes to fly unrealistically long routes in the game.
We are now in the process of adding real-life data for max payload range in addition to absolute max range, starting with the most commonly used aircraft families. However, because this change would mean many existing routes are no longer legal, the enhancement will take effect in each game world only after its current round finishes and resets.
Edit: This enhancement is still in the works and will not be activated in game worlds for the time being. I will post an update here when it will actually start rolling out.