the problem it the task of the airgroup. If the airgroup task is RETURN, the aircrafts often circle around their destination airfield, till running out of fuel. The task will become RETURN if a Aircraft is damaged or low on fuel. There is no way to change the RETURN-State into LANDING, so you must take care that all Aircrafts get Home before they 'decide' to do it automatically.
Here you will find a script example
http://forum.1cpublishing.eu/showpos...29&postcount=3
take a look on OnTickGame, i send the Airgroup home at a Fuellevel at 150 (Bf109 has a value of 300 on 100% Fuel so it's the half).
Lets hope this behavior is fixed in one of the next patches
