Hi there, either this is a bug or I'm stupiud, or both....but the fuel system of the 727 seems completely illogical to me.

By default, all 3 tanks are used and the CF valves are like this: - | -

on a long flight, I'm required to switch to center tank only, for this, I turn off the boost pumps of Tank 1 and 3, and need to turn on CF für 1 and 3. (I think to tell the system to accept the CF fuel from tank 2)

When I change back this state, and try to leave ALL CF switches on, fuel is only drained from tank 1 and 2, not tank 3.....why?
So to use all 3 tanks, I have to turn CF of 1 and 3 off.

Then I tried to make my engines use wing tanks only: So I switch all boot pumps of tank 2 OFF, the No. 2 CF ON, and CF of 1 and 2 OFF, then it drains fuel from all tanks. this changes, when I Turn No. 1 or No. 3 CF ON, then it only uses wing tanks.  But if I switich ALL CF on, then No. 1 and 2 tanks are used regardless of the pump state.

:D

anyone has an idea how to get the hang of this?