Recommended Posts

Since this keeps popping up, I'll mirror the Tutorial content here (though with a slight variation), and add a little bit of detail.

 

The >FUEL TANK/ENG message pops up to notify you that you need to configure the tanks such that each TANK is fueling an ENGine (TANK per ENG, or TANK/ENG). If you look at the FUEL page, you will see that the only pumps running all four engines up to this point are the OVRD pumps in MAIN 2 and MAIN 3. These pumps are heaving fuel out of these tanks to keep all four engines running, and the reason you're running all of the engines off of these tanks is that they can hold a lot more fuel than the outboards (think of the profile of the wing here). Once the inboard and outboard tanks are all at the same level, though, there's no longer a reason to be heaving fuel out of the tanks, so you turn the OVRD pumps off, and then set the engines up in a way that they all draw from their own tank (this also ensures that if there's a leak in a line between one of the tanks and an engine, you're not going to affect more than one engine, in theory).

 

Things you will see in the half-minute video:

  • FUEL TANK/ENG will happen when all tanks get down to being even, at about 30.0 (or 120.0 on the upper EICAS)*. Knowing this, I have the EICAS up to confirm the message and tank levels.
  • The OVRD pumps are turned off, and then the lower EICAS FUEL page is checked to verify that the individual tank pumps have taken over.
  • The outer crossfeeds are closed.
  • The final configuration is verified on the lower EICAS FUEL page, and the message is verified cleared on the upper EICAS.

 

 

I'll add this info to the Intro as well, as I'm sure it will help to have it there, too.

 

* 13.6 (or 54.4 on the upper EICAS) for those who use kilograms.

  • Upvote 5

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

Addendum: :smile:

 

So in the middle your flight you went to make a sandwich and cut your finger. After your return trip from the urgent care center, you discover not only that you have a  Fuel Tank/Eng caution message, but also that you now have a fuel imbalance. Oh, no! What do you do?

 

Easy. Just turn off your MAIN 2 and MAIN 3 OVRD pumps but leave the outer crossfeed valves open. Then turn off the MAIN 2 and MAIN 3 pumps off as well. Now the two engines on the left will be drawing fuel from tank 1 and the right engines will be fed by tank 4. Keep a close eye on your fuel levels on the fuel synoptic page. Once tanks 1 and 2 (and 3 and 4, respectively) have an equal amount of fuel, turn on the MAIN 2 (and 3) pumps (not the OVRD) and open the outer crossfeed(s).

 

The QRH says only "[c]onfigure the fuel pumps and crossfeed valves as needed to balance fuel," so I figured I'd show a way of doing this because, believe me, it will happen to you . . . more than once (unless of course you set up the plane to do this automatically).

 

Cheers!

Share this post


Link to post
Share on other sites
Thanks Kyle, this makes me understand better about this EICAS message.

 

Continue making these tutorials to avoid creating many posts for these common types of problems.

 

Cheers  :smile:  :wink:

Share this post


Link to post
Share on other sites

It is reasonably easy to rebalance the fuel if needed, as Walter pointed out. But, a good guide for those perplexed by this procedure. Cheers Kyle

Share this post


Link to post
Share on other sites

Best to not let it get to the point of needing to be re-balanced.

 

...but yes.

Share this post


Link to post
Share on other sites

Walter,

 

I believe the supplemental procedure for lunch calls for hitting the F/A button and requesting it be brought to you.

 

Have you tried this yet?  It works for me.

 

No knives.  No missed fuel reconfigurations.  :hi:

  • Upvote 5

Share this post


Link to post
Share on other sites

 

 


Best to not let it get to the point of needing to be re-balanced.
 
...but yes.
Indeed, but then we mix humans into it, and, well, you know the rest..

Share this post


Link to post
Share on other sites

On a related note:

 

Once tank to engine is established, tanks 1 and 4 are isolated, but there crossfeed between left and right, 2/3, is still open. Why are tank 2/3 crossfeed switches guarded, and why don't they get closed to prevent transfer? It's almost like flying a twin with the crossfeed left open.

Share this post


Link to post
Share on other sites

Interestingly, on takeoff, this is not the case. Tank>Eng is fully isolated until about 2500ft. I noticed this today KVCV-KPHX on the -F

Share this post


Link to post
Share on other sites

Trick when fiddling with fuel pumps is not to inadvertently deprive an engine of fuel...

  • Upvote 2

Share this post


Link to post
Share on other sites

Walter,

 

I believe the supplemental procedure for lunch calls for hitting the F/A button and requesting it be brought to you.

 

Have you tried this yet?  It works for me.

 

No knives.  No missed fuel reconfigurations.  :hi:

Unless of course you are a freight dog, in which case it is back to the above outlined procedure.  The main rule is never to confuse your R/W wife with a virtual F/A.  This rarely ends well.

  • Upvote 3

Share this post


Link to post
Share on other sites

I think too many people were spoiled with the high-tech, 21st century systems of the 777. :Tounge:  I have a blast flying the 747! 

Share this post


Link to post
Share on other sites

I think too many people were spoiled with the high-tech, 21st century systems of the 777. :Tounge:  I have a blast flying the 747!

 

Agreed, brother Gabriel, more hands on is great.

Share this post


Link to post
Share on other sites

Jordan,

 

The 2/3 Crossfeeds are managed by the Fuel Management cards automatically so they remain selected ON for managed and only turned OFF if you have a problem and require manual fuel management.

Share this post


Link to post
Share on other sites

You guys should make the manual pdf's pop up after the installation of the 747...but even then people wouldn't read it, I guess.  :P

Am I the only one who reads manuals before an addon aircraft is even released? No..? Ok... :rolleyes:

  • Upvote 2

Share this post


Link to post
Share on other sites

Trick when fiddling with fuel pumps is not to inadvertently deprive an engine of fuel...

If memory serves, it is a long time ago! when Ralph Tofflemire created the Vmax "ready for pushback"747-200. (FS9!!)

IIRC, on te FE's fuel panel you would have al least one X-feed (was it called that?) switch OPEN, in order to feed the manifold. (No pushbuttons, but switches yoy could turn horizontally or vertically).

In those days you had to watch the gauges, no eicas messages!!

 

So, the essence of the fuel management on the 744 still has  similarities to its famous predecessor?

 

regards,

 

Wijnand Lindeauf (EHBK)

Share this post


Link to post
Share on other sites

Agreed, brother Gabriel, more hands on is great.

Which is why it would be so great to have a PMDG 742 with a 743 expansion to fill out the family tree.  Just imagine...

  • Upvote 3

Share this post


Link to post
Share on other sites

 

Addendum: :smile:

 

So in the middle your flight you went to make a sandwich and cut your finger. After your return trip from the urgent care center, you discover not only that you have a  Fuel Tank/Eng caution message, but also that you now have a fuel imbalance. Oh, no! What do you do?

 

Easy. Just turn off your MAIN 2 and MAIN 3 OVRD pumps but leave the outer crossfeed valves open. Then turn off the MAIN 2 and MAIN 3 pumps off as well. Now the two engines on the left will be drawing fuel from tank 1 and the right engines will be fed by tank 4. Keep a close eye on your fuel levels on the fuel synoptic page. Once tanks 1 and 2 (and 3 and 4, respectively) have an equal amount of fuel, turn on the MAIN 2 (and 3) pumps (not the OVRD) and open the outer crossfeed(s).

 

The QRH says only "[c]onfigure the fuel pumps and crossfeed valves as needed to balance fuel," so I figured I'd show a way of doing this because, believe me, it will happen to you . . . more than once (unless of course you set up the plane to do this automatically).

 

Cheers!

 

 

Or the with non bleeding hand, use the mouse and go to the PMDG options pages, setting the TANK/ENG to be handled by the sim.  Terrible idea for the perfectly healthy to run the sim this way but in an emergency it does the job.

Share this post


Link to post
Share on other sites

Kyle, I wonder if you'd be willing to update your OP and specify that the numbers you gave are in pounds? The rest of the world aren't stuck in the past, you see, and we use sensible units  :wink:  =@

  • Upvote 2

Share this post


Link to post
Share on other sites

Kyle, I wonder if you'd be willing to update your OP and specify that the numbers you gave are in pounds? The rest of the world aren't stuck in the past, you see, and we use sensible units  :wink:  =@

Agreed, migh as well give us weight in doughnuts... :P 

Share this post


Link to post
Share on other sites

The >FUEL TANK/ENG message pops up to notify you that you need to configure the tanks such that each TANK is fueling an ENGine (TANK per ENG, or TANK/ENG). If you look at the FUEL page, you will see that the only pumps running all four engines up to this point are the OVRD pumps in MAIN 2 and MAIN 3. These pumps are heaving fuel out of these tanks to keep all four engines running, and the reason you're running all of the engines off of these tanks is that they can hold a lot more fuel than the outboards (think of the profile of the wing here). Once the inboard and outboard tanks are all at the same level, though, there's no longer a reason to be heaving fuel out of the tanks, so you turn the OVRD pumps off, and then set the engines up in a way that they all draw from their own tank (this also ensures that if there's a leak in a line between one of the tanks and an engine, you're not going to affect more than one engine, in theory).

Thanks Kyle for this detailed explanation!

 

So just for my own understanding/clarification:

 

I am currently on a long-haul flight.  I have 25000 KG in center tank, 37,600 KG in two inner main tanks and 13,600 KG in outer main tanks. I start with all pumps on including override pumps (except for L & R Stab tank pumps as these tanks are empty).

 

The 747 will burn the center tank first; when it's near empty I shut off the center tank pumps.

 

The two inner main tanks have much more fuel to begin with than the outer ones, so the override pumps are on to force more fuel from these two tanks. 

 

When the two inner main tanks' quantities equal the two outer main tanks' quantities, I shut off the override pumps to have all the main tanks pumping at the same rate to keep fuel balanced. I also close the two outboard X-Feeds.

 

The reason to have the two outboard X-Feeds open until the two inner main tanks have the same amount as the outer two, is that otherwise engines 1 and 4 would draw fuel from the two outer main tanks only, making a balanced condition impossible to obtain. 

 

Thanks,

Mike

Share this post


Link to post
Share on other sites

did I miss the detail about the fuel systems in tutorial 1? I don't remember seeing it. Also, is there no FCTM for the 747?

Share this post


Link to post
Share on other sites

did I miss the detail about the fuel systems in tutorial 1? I don't remember seeing it. Also, is there no FCTM for the 747?

Technically, the tutorial says that a description of the fuel system would be covered elsewhere, but it didn't say where. In this case, elsewhere meant you'd have to look in the FCOM (so that answers your second question).

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now