Engine goes out with 0% int. fuel

[Moafuleum]

Hi

I know the thread title is hilarious, but wait ;)

 

I set up a simple mission in the ME, starting in-air. In the ME i configured the plane, such that there is 0% internal fuel but with two full drop tanks. On the engine page on the MFCD there is pointed out a fuel weight of ~4000. Right after clicking the start button the engine shuts off due to no fuel (i guess) although the droptanks should provide enough fuel for quite some flight time.

 

Setting the infernal fuel in the ME to ~5% instead, grants you plenty of flight time due to the droptank fuel supply. Is it a bug or am i missing something?

[NastyFruit]

When starting the mission, the pylon fuel lines where the external tanks are mounted are empty, and need to fill up first to get the fuel to the engine, and in that time, the engine dies. (Just a guess, I have no idea. (I am sure its not modeled that way, but I bet you that is what it comes down to.)) ;)

[Nero.ger]

guess:

airplans have feed-tanks which fuel gets pumped in bevor it goes out to the turbine. Since it cant be filled in an instant, there is no fuel for the turbin because all fuel is in the external tanks

[timber3000]

My understanding of how a fuel system work on an airplane is this: the fuel pump are in the internal tanks. Therefore, if no internal fuel, no fire...

 

Your external tank feed the internal one. But they are not connected directly to the engine. Same with wing tank, they just feed the fuselage tank. That why the fuselage tank is always the last to empty.

 

I have no experience on the harrier, but that how it work on most plane anyway.

[mvsgas]

Hi

I know the thread title is hilarious, but wait ;)

 

I set up a simple mission in the ME, starting in-air. In the ME i configured the plane, such that there is 0% internal fuel but with two full drop tanks. On the engine page on the MFCD there is pointed out a fuel weight of ~4000. Right after clicking the start button the engine shuts off due to no fuel (i guess) although the droptanks should provide enough fuel for quite some flight time.

 

Setting the infernal fuel in the ME to ~5% instead, grants you plenty of flight time due to the droptank fuel supply. Is it a bug or am i missing something?

 

Sounds like it is working as it should.

[NeilWillis]

The question I ask is the same one I asked when I read today that a guy got his head stuck when he filled a microwave with concrete and then stuck his head in it.

 

Why?

 

As an experiment I guess is the answer to both, but you do have to ask what the logic was. In reality, the external tanks are emptied first, leaving the internal tanks full until the external ones are empty.

 

Or do you think developers have a session asking what bugs they need to squash if people do the things that no one sane would do? I'm not suggesting they have a contingency plan in case someone can't put their VR gear on because they have a microwave full of concrete stuck on their heads mind you!

 

Excuse the rant, but asking why something doesn't work when in reality it couldn't arise unless there was a serious fault that would ground any aircraft anyway seems a tad redundant wouldn't you agree?

[Eldur]

Noticed this as well in another module, just can't remember which one it was. But I think it's general behaviour of the engine. 0% internal fuel = no luck, no matter how many external tanks are there. Should be possible to pump it to the internal ones though.

 

But now comes the interesting part. This one shut down before it was completely empty:

 

 

Just made my landing that close. Couldn't get off the runway due to the shutdown shortly after, but could have done it. It definately wasn't down to 0.

Only explanation I have would be that the tiny rest of fuel is sitting in the tank with the pumps unable to get it out.

[ESAc_matador]

In the NATOPS they say that the fuel goes from the most external tank, to the internal fuel tank, to the internal aircraft tank.

 

So, if you dont have your engine running... probably the pumps does not work. (may be with the APU...) but, seems to me that the model is right.

Edited December 8, 2017 by ESAc_matador

[mvsgas]

From working on other aircraft, external tanks need air pressure to transfer fuel (Look like the N/A is the same) So without engine running, tanks will not transfer. Additionally, many aircraft use siphoning. So, for example, in the F-16 external tanks transfer to the wings, so if the wing empty before external tanks, that fuel may be trap in the externals. ( the engine can use fuel faster than the external wings can transfer) AFAIK, reading the RL manual for the AV8B, (have not read the fuel section completely mind you) it works similarly.

 

Also, many fuel system have an error. Normally plus or minus 300 pounds. That is why many fighter aircraft land with a couple of hundred pound of fuel (if not more). Lowest I saw was an F-16 at 800lbs and the pilot was desperate to shut down in the parking spot.

 

For comparison, aircraft like the F-15, don't even transfer fuel out of their external tanks until airborne and many can't transfer fuel out of the external with in flight refuel door/probe open/extended. Normally opening the door or extending the probe depressurizes the fuel system.

Edited December 8, 2017 by mvsgas

[Eddie]

Yeah, as mvsgas says, external tanks are not generally pumped (with a couple of exceptions) and instead rely on either siphoning or pressurizing the tanks with ECS air to force the fuel out. And tanks don't generally feed with weight on wheels.

 

Fuel also feed through the tank in serial, ie from external, to wing, to fuselage, to feed. If the engine feed tanks are already empty, there's no way to get fuel to the engine(s) before the shut down due to fuel starvation.

[Zeus67]

Hi

I know the thread title is hilarious, but wait ;)

 

I set up a simple mission in the ME, starting in-air. In the ME i configured the plane, such that there is 0% internal fuel but with two full drop tanks. On the engine page on the MFCD there is pointed out a fuel weight of ~4000. Right after clicking the start button the engine shuts off due to no fuel (i guess) although the droptanks should provide enough fuel for quite some flight time.

 

Setting the infernal fuel in the ME to ~5% instead, grants you plenty of flight time due to the droptank fuel supply. Is it a bug or am i missing something?

 

There is no fuel in the feed tanks, which are internal.

If the feed tanks are empty, then the engine will shut down for lack of fuel even if you have fuel in the external tanks.

[Moafuleum]

Thanks for all the answers, this seems plausible to me :doh: