APU Fuel Logic...

[Epikk 62]

Hello again PMDG team...I was wondering if the APU Fuel Logic was defenitely out of the 737NG Series??

[Guest wee_davie_2612]

If it is, PMDG, any chance of adding it back in?CheersDavid

[Guest wee_davie_2612]

Bump... Anyone got an answer?David

[Guest ba747heavy]

The APU system does not take fuel from the tanks. Someone from inside of PMDG will have to tell you there plans, or lack of, for fixing it, because I don't know.

[Epikk 62]

Thanx for the reply Fred...I miss this feature sometimes...:)

[Guest wee_davie_2612]

Hey,I know it used to be there, it's written in the update and fixes file:

[crvm 0]

There is slightly more of an issue than that so I am sure we will not see this feature back in the 800-900, Lefteris can comment more on the reasons.[h4]Best Wishes,Randy J. Smithhttp://www.precisionmanuals.com/images/forum/betaimg.jpgAMD 64 3200+|ASUS KV8 DELUXE|GFORCE 5700 ULTRA|WD SATA 80 GIG|512 DDR 400|

[Epikk 62]

> There is slightly more of an issue than that so I am sure we>will not see this feature back in the 800-900, Lefteris can>comment more on the reasons.>Unfortunately... That's the way I feel it too : "APU" won't be back... Seemed like a really complicated issue.

[Guest wee_davie_2612]

Go get Lefteris on the blower :)As I said above, my knowledge of gauge programming would half fill a thimble. The most I've done is simple XML click sposts, a couple of switches and radio controls.Hell, if PSS can do it....(I don't feel one bit guilty saying that, 'Once bitten...' as the saying goes) CheersDavid

[Qavion 19]

David....Don't believe every schematic you read (I've made that mistake too many times before ;-)). According to the Boeing 737NG Maintenance Manual, the APU can use fuel from any tank. However, if all the main tank fuel pumps are off, the APU will siphon fuel from the #1 tank.Cheeers.Ian.

[Guest EISN_CONTROL]

I'd certainly like to see this feature implemented again although I'm pretty sure it has something to do with the major problems we experienced in version 1.0.John http://homepage.eircom.net/~eamonnmca/images/logo_ba.JPGwww.bavirtual.co.uk Senior Captain Simflight.com Staff Reviewer

[Guest wee_davie_2612]

>David....>Don't believe every schematic you read (I've made that mistake>too many times before ;-)). According to the Boeing 737NG>Maintenance Manual, the APU can use fuel from any tank.>However, if all the main tank fuel pumps are off, the>APU will siphon fuel from the #1 tank.>>Cheeers.>Ian.Hey Ian,The schematic above shows that it can use fuel from all tanks but only if the boost pumps are switched on and the cross feed is open. If the cross feed is closed and all the boost pumps are on, then a fuel imbalance between the main 1 and 2 tanks will still occur.I would like to see it reimplemented aswell. The whole idea of a aircraft like this is to go for realism, the APU having no effect on the fuel quantity isn't realistic.John, what were the problems faced in the early versions?? I only bought the NGs recently, after they were upgraded to v1.3.CheersDavid

[Guest Ray CYYZ]

If memory serves, the PMDG fuel system does time slicing, alternating between the fuel tanks, stealing from one then the other and back and forth. This was required to fix some problems with the engines cutting out back in a earlier release or so I remember Robert's explanation. This had something to do with the way FS handles multiple fuel tanks and the limitations imposed by FS on the aircraft developer (ie: you can only pull fuel from 1 tank at a time or something of the sort, and they for obvious reasons needed to attach one engine to each tank separately which FS wouldn't allow).Not really sure of the specifics, but thats what I remember.Ray

[Guest wee_davie_2612]

Hey Ray,That'd explain why the APU can't suck gas from only the right tank then (under the conditions outlined above). Interesting.I'd still like to hear from Lefteris to see if it was looked into again for the upgrade and if any headway was made.CheersDavid

[Guest Ray CYYZ]

Yep, would be interesting to know if the SDK helped them out.I think it would really matter with all the extra tanks/configurations on the BBJ/BBJ2, it would be nice to get those 2 extra little panels added to the 800/900 to be able to have the extra fuel tanks even if they never do a full BBJ/BBJ2 release as a separate product.Ray