Hi,I simulated a fuel leak and out of curiosity let the fuel drop to 0. Shortly before running out of fuel, I started the APU.The result was that my right engine flamed out, but both the APU and the left engine kept running. Even for a prolonged time (20 minutes with 0.1 tons remaining...)RegardsMark

Hmmmm....I managed to start the APU and keep it running wihtout any fuel pumps selected....is this normal or does the APU draw fuel anyway?

Check your FSX settings. You might have the "Unlimited Fuel" option selected, which might allow that.

Hmmmm....I managed to start the APU and keep it running wihtout any fuel pumps selected....is this normal or does the APU draw fuel anyway?

Yes, it is possible to draw fuel without pumps engaged.

Edited February 10, 201214 yr by audiohavoc

Yeah, the APU has its own fuel pump. SOP's say to keep a main pump running (center is best if the tank has gas) to keep wear down on the APU one if you need the APU for long periods.

Hmmmm....I managed to start the APU and keep it running wihtout any fuel pumps selected....is this normal or does the APU draw fuel anyway?

I believe the engines (not sure about APU, sounds like it has it's own pump) are gravity feed systems. This means that they can run without the pumps. However, gravity is a funny thing in a aircraft that maneuvers and the fuel pumps are there to provide a steady and sufficient flow of fuel in all conditions.Eric Szczesniak

Edited February 10, 201214 yr by ESzczesniak

My APU shut down when I forgot to feed with the other tanks and the #1 tank was empty.I'm pretty sure it will do the same also the engine, but I will try it.

Do you have the latest version? I'm pretty sure that low pressure of the pumps was not simulated with low fuel in the first release, in that condition engines and APU will run until you reach 0. Then they updated simulating pump low pressure before reaching 0 (as it is supposed to be) and as you can see my engines shut down when I put 50Kgs of fuel in both tanks. Looking at the overhead I can see that the right fwd pump is the only pump without low pressure at the moment.

HI,yes I'm sure I have the latest version (downloaded it a week ago)When testing, make sure you don't set a specific fuel value but let it run dry.And as said, it works partially - the right engine did flame out, but the left one + the APU kept running.I did get a low pressure warning on the fuel pumps though.If you want to try to replicate it: I had set a fuel leak failure at the start of the flight (perhaps this matters)

I tried, with strange results, maybe similar to yours.right engine shut down first, with the right fwd pump not in low pressure condition, then at 79Kgs also the engine 1 shut down (apu still running), using crossfeed I was able to use the rh tank fuel to restart engine 1, it worked and fully emptied the tank, so I had 79Kgs on the left, 0 on the right. It continued for a minute maybe, with thrust set at 100% N1 or around it, then I tried to run back with the left tank, I turned the pumps back on and tried to close the crossfeed. as soon as I closed the crossfeed the engine and APU shut down. It was then impossible to start it again. I'll test it again to find where is the problem.I've not used the failures, I just emptied the tanks to 200kgs and then waited.

Tried again. Same result.This time I tested on ground. When restarting I found another bug that was already posted before. It was about the starter cutout.I made a video, this will help you to confirm if it is the same problem you have.I'll load on youtube and post it here.

Hi Andrea,yes that seems about right. I also had a fuel pump without low press showing and my crossfeed was also open.Thanks for looking into this. Are you in contact with PMDG?RegardsMark

Did you submit a ticket?

not yet, it is one of what I think is a "small" issue as normally noone will run with dry tanks.This is confirmed by the fact that Mark found it the first time after months from the release.If you want I'll send it, I still have an opened one for other reasons, I can add it to it.But, if confirmed from the team, it could probably lead in a delay of the sp1c or maybe planned to the sp2.