This is on SU10b: I’ve run into a situation while working on an implementation
of the modern fuel system. This issue I had was that although I was able to
successfully configure the system so that it worked (watching fuel pressures,
flows, etc through the lines via the simvar watcher), it ALSO works without
any fuel present. The strange thing is that I can see the fuel being
successfully drawn from the selected tank when fuel is present. But if I
change the tank quantity to zero, the engine continues to run, lines continue
to show pressure & fuel flow, etc. I can even load the aircraft with zero
fuel, and successfully start and operate the aircraft with no issue. While
debugging this, I created an extremely simply fuel system to eliminate all
possible (that I can spot) configuration issues, posted below. Note that this
is on a Piston engine, and the unlimited fuel assist is definitely turned off.
I’ve also attached a screenshot of the simvar watcher, where you can see the
output of the relevant simvars. [FUEL] fuel_type =1 [FUEL_SYSTEM] Version =
Latest Engine.1 = Name:main_engine #Index:1 Tank.1 =
Name:front_tank#Title:Front
Tank#Capacity:35#UnusableCapacity:1#Position:-7,0,-1#OutputOnlyLines:line_01
Line.1 = Name:line_01 #Source:front_tank #Destination:wobble_pump Line.2 =
Name:line_02 #Source:wobble_pump #Destination:engine_pump Line.3 =
Name:line_03 #Source:engine_pump #Destination:main_engine Pump.1 =
Name:wobble_pump #Pressure:5.5 #DestinationLine:line_02 #Type:Manual
#PressureDecreaseRate:0.05 Pump.2 = Name:engine_pump #Pressure:5.25
#PressureCurve:1 #DestinationLine:line_03 #Type:EngineDriven #Index:1 Curve.1
= 0:0, 0.1:0.1, 0.15:0.15, 0.2:0.7, 0.25:0.9, 0.5:0.95, 1.0:1.0
Hello @MV-JimStewart As you can see in the SimvarWatcher screenshot you
provided, you still have fuel in your fuel lines. Your engine will keep
running until the lines are out of fuel as well. At idle, it can take a while
to run out. And fuel lines will contain fuel even when you start your flight
with empty fuel tanks. Regards, Sylvain
Hi @FlyingRaccoon I’ve seen you post the same response previously, so this was
something I accounted for. 1) The aircraft will continue to run, without
stopping, ever. 2) The fuel levels shown in the Simvar watcher remain at a
constant level, without decreasing. Perhaps this is the cause of the issue?
The fuel is present in the lines so the engine runs, but since the fuel in the
lines is never depleted, it continues to run? I’ve also that the manual fuel
pump is capable of building fuel pressure irregardless of whether there is
fuel in the tank(s) or if the fuel has a valid path to the pump.
No my plane quits running in a matter of seconds I can’t even raise the idle
as it does so fast which won’t let me taxi or even fly for that matter!