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FlyToday avatar image
FlyToday asked FlyToday edited

Fuel Line Unable to Draw Fuel from Tank

Hey all! I created a very simple fuel system just as a proof of concept before I start mucking with my real data. The good news is that the jet engines will start and run just fine, right up until the fuel in the lines runs dry, which is the bad news. I have 2 engines and for each, I have a dedicated fuel tank, electric pump, shut-off-valve, and engine pump. I then have a fuel line connecting each component. I looked through the CFG files, even swapping in the CJ4's files just to see if it can work, but it still will not draw fuel from the tank. Here is the setup for just one of my engines (the other one is identical). I verified that the electrical circuits had power and the tanks had plenty of fuel (180 gal+). Also, via SimVar Watcher, I verified that the valves were open and the pumps were on as well as whether there was fuel flow in all lines. All of those were true except for the one line from the tank to the electric pump which did not have any fuel flow. Anyone run into this or have any ideas? Am I missing something? Thank you.


fuel_type =2


Engine.1 = Name:LeftEngine #Index:1

Tank.1 = Name:LeftMainTank#Capacity:187.2#UnusableCapacity:5#Position:-32,-6,1#OutputOnlyLines:LeftMainTankToBoostPmpLine#Priority:3

Line.1 = Name:LeftMainTankToBoostPmpLine#Source:LeftMainTank#Destination:LeftWingBoostPump

Line.2 = Name:LeftBoostPmpToBoostJctnLine#Source:LeftWingBoostPump#Destination:LeftSofValve

Line.3 = Name:LeftSofVlvToEngPmpLine#Source:LeftSofValve#Destination:LeftEnginePump

Line.4 = Name:LeftEngPmpToEngineLine#Source:LeftEnginePump#Destination:LeftEngine

Valve.2 = Name:LeftSofValve#Circuit:73

Pump.1 = Name:LeftWingBoostPump#Pressure:25#TankFuelRequired:LeftMainTank#DestinationLine:LeftBoostPmpToBoostJctnLine#Type:Electric#Index:75

Pump.2 = Name:LeftEnginePump#Pressure:25#PressureCurve:1#DestinationLine:LeftEngPmpToEngineLine#Type:EngineDriven#Index:1

Trigger.1 = Name:AutoStart#Condition:Autostart_Enabled#EffectiveTrue:OpenValve.LeftSofValve, OpenValve.LeftMotiveValve,StartPump.LeftWingBoostPump,StartPump.LeftEnginePump

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FlyToday avatar image
FlyToday answered FlyToday edited

The issue was on my end, sort of. According to the SDK it says to use the circuit index for pumps and valves and does not mention to use the circuit "type" Index. In addition, my Simvar watcher displayed a "1" for my FUELSYSTEM PUMP ACTIVE:xx which of course lead me to believe that there was no issue with the fuel pump when there clearly was. I in turn spent months trying everything that I could think of, except for this. Anyway, if you use the circuit type index, your pumps and valves will work.

MS please update this in the SDK doc's so the next person does not need to spend countless hours trying to figure this out. Thank you.

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