Editing the A320neo's fuel capacity

Looking for some help with modding the fuel capacity of the A320. Editing the capacity of the tanks in the [FUEL] section of flight_model.cfg doesn’t seem to do anything.

As a test, I made two simple mods, one for the C152, and one for the A320. In both cases, I doubled the capacity of the LeftMain tank. For the A320, I also increased max_gross_weight in [WEIGHT AND BALANCE] to some arbitrary value. Please find the mods here:


For the C152, the change appears in the fuel menu, but for the A320, only the change in max_gross_weight appears to have been applied. No change in the fuel capacity was observed. I’m rather puzzled as to why that might be the case. Does anyone have any idea as to why the change in fuel capacity is not applied?

I bet you are on the right-track, Sandy, but there may be another parameter in that file, or one of the other CFG files that are in the root directory too. That’s just a guess though.

Go ahead… Snoop around!

One difference I’ve noticed is that there’s a [FUEL_SYSTEM] section in flight_model.cfg for the A320, but not in the C152. I can’t see what that’s got to do with the problem at hand though, since I’m not adding or removing any fuel tanks.

Edit: oh wait, just spotted some values under that section under “Tank.x:”. Might they simply be display texts? Or code comments? Can’t see how they’re linked to the entries under [FUEL] though. (Unable to test it at the moment.)
Tank.1 = Name:Center#Title:TT:MENU.FUEL.CENTER#Capacity:3000#UnusableCapacity:0#Position:-6,0,1#Priority:1#OutputOnlyLines:TankCenterToCenterTankPump1,TankCenterToCenterTankPump2

Just as a thought, it’s the fuel consumption that seems to be off in the A320, maybe that’s better to look at. And I believe has been proven to be doable since the A32NX mod has done it.

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Turns out the figures under [FUEL_SYSTEM] were it! Happy!

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What did you end up changing it to?

I just scaled the capacity of each fuel tank up such that the total capacity is equal to that of the A350-900ULR:

[FUEL]
LeftMain = -9, -13, 2, 11310, 0 ; For each tank: Tank position (z longitudinal, x lateral, y vertical) (FEET), total fuel capacity (GALLONS), unusable fuel capacity (GALLONS)
RightMain = -9, 13, 2, 11310, 0
Center1 = -11, 0, 1, 18860, 0
LeftAux = -13, -27, 3, 1260, 0
RightAux = -13, 27, 3, 1260, 0

Ah, okay thanks. I had noticed that the Asobo neo fuel tank capacities do not agree with the FAA and EASA data sheets and wondered if maybe you were trying to correct for the same thing. The data sheets show 3 tanks with a max capacity of 6267 gallons of usable fuel whereas the sim uses 5 tanks and 7000 gallons.

I guess you could set the capacity of the auxiliary tanks to 0 if you want only 3 tanks. Beyond that, I’ve not fiddled with reconfiguring the layout of the fuel system so I’m afraid I can’t be of any help there. Good luck with your mod!

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Found this as I was thinking about the same stuff (and tank capacities seem to change with every other update of the FBW A320 :wink:). aircraft systems - What is the capacity of the vent surge tank in an A320? - Aviation Stack Exchange. Doesn’t say which model of A320 though :roll_eyes:

look at ESP documentation btw, some parameters are the same as FSX’s

I’m doing some research on this a/c to create some additional modifications for the FBW a320neo and possibly a separate flight dynamics tune for the default model for those who don’t want the extra avionics capabilities / complexity of the FBW model. Fantastic effort there - am working on flight dynamics tuning to get the performance even closer in line with the real bird. It appears that some of the confusion around the fuel tank volumes relates to the type certificate data sheet for the A320neo vs. the ACJ320neo (corporate jet version). Even the wikipedia entry and the Airbus literature I’ve seen refer to a fuel volume that appears to be for a “four tank airplane” configuration. However, as far as I can tell, the commercial fleet model appears to be what’s referred to as the “three tank airplane” model and has a total capacity of 23724.7 liters (19050.9 kgs) unusable 82.1 liters (65.9 kgs) - so FBWs present entries appear to be accurate. However, the ACJ320neo apparently has the stated capacity for 4, 5, 6, or 7 total tanks with anywhere from 26862.7 liters (the 7000+ or so gallons Asobo originally included for this a/c) to as much as 34416.7 liters. I don’t know if any commercial fleet aircraft have been outfitted with more than the standard three tank equipment - based on the EASA data sheet from summer 2020 it would appear for the time being this has not been certified. The additional center tank (ACT) modification seems specific to the corporate jet and has its own set of specific modification certificate numbers. However, the notes in the data sheet indicate that this is good for the addition of four ACTs bringing capacity up to the 34400+ liters (a little over 9000 gallons). There are several other certifications specific to the corporate jet version that would appear to apply - I’ve quoted those below. Just as a side thought, an ACJ320neo with 7 total tanks would have a heck of a range - easily over 6000 NM - this appears to fall in line with the ACJ320neo marketing literature from Airbus.

“A320-251N, -271N, -272N for Corporate Jet use (commercially identified as ACJ320neo) are
defined through the following set of modifications:
modification 163215: Installation of up to 4 ACTs
modification 162744: Extension of the flight envelope up to 41000 ft
modification 23398: Install stairs at fwd pax door.
modification 162193: Lower Cabin Altitude activation
modification 162339: Certify Envelope for design weight of ACJ320neo”

As an additional note, it’s my understanding that the fuel volumes listed in the flight_model.cfg file are for total fuel tank volume after which there is a reference for the unusable amount, which is a subset of that total volume.