First of all thanks Paul for a new version of your amazing .dll!
Then I used the way you gave me the example with this code:
Try FSUIPCConnection.Open(FlightSim.FSX) Dim ps As PayloadServices = FSUIPCConnection.PayloadServices ps.FuelTanks(FSFuelTanks.Left_Main).LevelUSGallons = 50 ps.WriteChanges() MsgBox("Done") Catch ex As Exception MessageBox.Show(ex.Message) End Try [/CODE] And I always get an error saying the following: "Index is out of bounds. He shouldn't be negative und be below the list. Parametername: Index" (Since my PC is a German one, I get the German message of it: "Der Index lag außerhalb des Bereichs. Er muss nicht negativ und kleiner als die Auflistung sein.Parametername: index" and I translated it into English as best as I can) That makes me mad. My aircraft.cfg says the following under fuel: [CODE] LeftMain = X.X, X.X, X.X, 158.0, 3.6 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons) RightMain = X.X, X.X, X.X, 158.0, 3.6 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons) [/CODE] I cannot find again my mistake since FSX is running and the airplane is loaded. This also happens with different airplanes like Majestic Q400, so basically it is wrong or? thanks for your help