Hi iniBuilds team,

with v1.2.7 I notice a significant increase in fuel consumption by around 1.1 t per hour. According to the Flightplan provided by Simbrief the AVG FF KGS/HR should be 6221 - it is around 7400 during flight. It used to be pretty spot on before v1.2.7 - now it's impossible to reach the destination airport. Anybody experience the same behaviour? Any ideas or workarounds?

Same here, crash in the ocean before 300nm from destination

Plus one for this. Same issue.

same here :(

Did you guys monitor EFOB at destination during the flight? I just flew for a couple of hours and the EFOB stayed at 5.6--5.7 T during the whole flight (but I ended up at the gate with about 4200 kg. Is that consistent with your observations, that the calculated EFOB @ DEST stays reasonable through the flight but ends up overestimating?

28 minutes ago, Gungnir said:

Did you guys monitor EFOB at destination during the flight? I just flew for a couple of hours and the EFOB stayed at 5.6--5.7 T during the whole flight (but I ended up at the gate with about 4200 kg. Is that consistent with your observations, that the calculated EFOB @ DEST stays reasonable through the flight but ends up overestimating?

Yes, EFOB at destination stayed pretty much the same all flight. Maybe increased a slightly bit the longer the flight was and the lower the FF got over time.

Hey, I just finished the second flight with 1.2.7 and fuel factor is like 6 %, yes :-)

https://galerie.klusik.cz/gallery/game-screens/flight-simulators/a350/from-prague-to-princess-juliana-international-airport-lkpr-tncm/?lang=cs&presentation=1&autoplay=1&presentation_fullscreen=1&presentation_music=1&presentation_interval=medium&presentation_transition=slow&presentation_exclusive=0

You can download my simbrief there and crosscheck it with my measured data: LKPR TNCM A350 1.2.7.zip

I made a script which saves my flight data during the flight, maybe it could be helpful to anybody :-)

A350_1.2.7_LKPR_TNCM_fuel_comparison.csv iniBuilds_A350_1.2.7_LKPR-TNCM_Fuel_Analysis_EN.pdf

Edited October 24Oct 24 by klusik
Added PDF with analysis and CSV with data table

Plus one. This has been my experience as well. The SimBrief plan and the EFOB/actual consumption are way different.

Edited October 25Oct 25 by Bacsa Attila

Hello again,

I've now completed the P06 fuel factor flight here: https://galerie.klusik.cz/presentation=1ec2bc09

As I mentioned before here: https://forum.inibuilds.com/topic/41833-127-fuel-flow-increased-significantly/#findComment-101842

Raw data: TNCM LKPR A350 1.2.7 FUEL FACTOR P06.zip

OFP attached for comparsion. I let ChatGPT to compare the data and attach the PDF as well.

It looks like the P06 is about right, so far. I know it could be changed and probably (my guess) is they (inibuilds) tuned it to SU7 and with SU7.1 patch it just went against itself, but this is must my guess :-) With P06 my divergence off plan is about 0,2 %, which is nice, I guess :-P Planned trip fuel was 53 970 kg and real was 53 866 kg :-)

TNCM LKPR simbrief-ofp.pdf

A350_v1.2.7_TNCM-LKPR_P06_Fuel_Analysis_EN.pdf

Edited October 25Oct 25 by klusik
Fuel analysis added

Thanks for your reports everyone. I have logged this with the team to review.

Appreciate your patience!

@iniKyle

Is this potentially related to the MSFS update which made changes to drag profiles?

The aircraft now struggles to climb above FL350 - regardless of weight.

I've attached a photo where the aircraft has climbed to FL370 - well within the performance window, but is struggling to get to .85, so will inevitably run out of fuel as it demands more thrust trying to maintain the ECON speed... at cost index 3!!!

Edited Tuesday at 09:12 PM5 days by MasterLorenzo

6 minutes ago, MasterLorenzo said:

@iniKyle

Is this potentially related to the MSFS update which made changes to drag profiles?

The aircraft now struggles to climb above FL350 - regardless of weight.

I've attached a photo where the aircraft has climbed to FL370 - well within the performance window, but is struggling to get to .85, so will inevitably run out of fuel as it demands more thrust trying to maintain the ECON speed... at cost index 3!!!

This very well could be the drag/perf issue reported to MSFS/Asobo.

The team will have to do a little more research before we can confirm this though.

We appreciate your patience!

Are there any updates here? I don't know how much fuel I need to load.

I believe there's an SU7.2 beta now with a fix for this from Asobo, so hopefully the inibuilds team didn't adjust the flightmodel so that it breaks again when SU7.2 becomes public...

Edited Friday at 05:22 PM2 days by Gungnir

26 minutes ago, Gungnir said:

Are there any updates here? I don't know how much fuel I need to load.

I believe there's an SU7.2 beta now with a fix for this from Asobo, so hopefully the inibuilds team didn't adjust the flightmodel so that it breaks again when SU7.2 becomes public...

I don't believe we have made any changes, based on exactly this.

Thanks for your patience 🙂

2 hours ago, iniKyle said:

I don't believe we have made any changes, based on exactly this.

Thanks for your patience 🙂

The new patch notes include a line about fuel though. Could you find out what changed? Do we still need to use custom simbrief fuel factors etc? Thanks!

To be clear, the reason I bring it up is:

https://devsupport.flightsimulator.com/t/su7-engine-performance-or-drag-is-wrong/18609/54

EDIT: Oh I see, I think the Simbrief profiles have P11 now? I didn't catch that because I had a saved airframe and that doesn't update, apparently.

Edited Friday at 08:13 PM2 days by Gungnir

24 minutes ago, Gungnir said:

The new patch notes include a line about fuel though. Could you find out what changed? Do we still need to use custom simbrief fuel factors etc? Thanks!

To be clear, the reason I bring it up is:

https://devsupport.flightsimulator.com/t/su7-engine-performance-or-drag-is-wrong/18609/54

EDIT: Oh I see, I think the Simbrief profiles have P11 now? I didn't catch that because I had a saved airframe and that doesn't update, apparently.

Correct! Let me know if the P11 factor seems to correct the fuel burn discrepancies.

Thanks 🙂

8 minutes ago, iniKyle said:

Correct! Let me know if the P11 factor seems to correct the fuel burn discrepancies.

Thanks 🙂

Will do, but hopefully the SU7.2 fix will come soon too.

Appreciate the patch cadence lately!

@iniKyle & @Gungnir Hello, I have noticed your repsponses, great, thank you!

Just a question about the P06 and P11, what should I do then to plan a flight? Still to use P06? Or just use P00 and it will predict the correct ammount from simbrief?

I am not sure what does the update message mean exactly, I know you changed "something", but not sure what exactly and what will follow for us, fliers :-)

Thank you for the amazing work you are doing :-)

1 minute ago, klusik said:

@iniKyle & @Gungnir Hello, I have noticed your repsponses, great, thank you!

Just a question about the P06 and P11, what should I do then to plan a flight? Still to use P06? Or just use P00 and it will predict the correct ammount from simbrief?

I am not sure what does the update message mean exactly, I know you changed "something", but not sure what exactly and what will follow for us, fliers :-)

Thank you for the amazing work you are doing :-)

For the time being, try P11 on your simbrief flight plan. If you're able, report back after a flight or two using P11.

Thanks 🙂

Just now, iniKyle said:

For the time being, try P11 on your simbrief flight plan. If you're able, report back after a flight or two using P11.

Thanks 🙂

Okey, I'll try and let you know later (you know... must do this flight first :-P )

First thing -- aircraft computed 61.9 T for LKPR->KORD, I have 88.2 T onboard, 30 minut ATC reserves, 60 MIN WX reserve. P11 factor.

Interesting, the "enroute burn" from simbrief is 65,2 T, but I got it, for P11. But aircraft think 61,9 T is enough :-)


Simbrief is giving me this, I'll send more as the flight concludes (I have the data miner through simconnect, I'll send these after the flight is done)

Edited Friday at 10:16 PM2 days by klusik

@iniKyle

Aaaaand nope :-|

Anyways: Flight with some data: https://galerie.klusik.cz/gallery/game-screens/flight-simulators/a350/test-flight-for-inikyle-from-prague-to-chicago-lkpr-kord/?lang=en

Raw flight data: LKPR KORD WASM c6b4233f8633440da0293a8cdf502f6f.rar

Simbrief and analysis you have in the gallery (first link) for download in PDF.

I hope this helps at least a bit, but it seems the initial few hours of flight were ok (at least for the fuel consumption)

Edited Saturday at 04:48 AM1 day by klusik

yep i have the same Problem, flying HEL-HKG fuel calculated to Simbrief 83.5 Tons and Enroute 70 Tons. the A350 sais EFOB 3.3 to 4 Tons Rest flight time around 6h and Fuel in tanks 37 Tons, Used Fuel with Flighttime 5:40h 48.3 Tons.

2 hours ago, JNAS308 said:

yep i have the same Problem, flying HEL-HKG fuel calculated to Simbrief 83.5 Tons and Enroute 70 Tons. the A350 sais EFOB 3.3 to 4 Tons Rest flight time around 6h and Fuel in tanks 37 Tons, Used Fuel with Flighttime 5:40h 48.3 Tons.

Which fuel factor (Pxx) in simbrief?

19 hours ago, iniKyle said:

For the time being, try P11 on your simbrief flight plan. If you're able, report back after a flight or two using P11.

Thanks 🙂

Has this been thoroughly tested? Compared against IRL consumption?

Please note that the A359 is affected by the prediction issues, but not the A35K. The latter seems to still require the old fuel flow factors.