Something I've now noticed that could also be part of the problem (illustrated with an example): the flight plan in the FMS is fully populated (F-PLN page), but no step climbs have been entered yet. The aircraft is fueled. On the FUEL/PAYLOAD page, the planned ZFW and ZFWCG as well as the block fuel are entered. In the fuel section of that page, trip fuel shows 70 t and an EET of 06:10. The same values appear in the footer of the F-PLN page. The SimBrief flight plan shows a trip fuel of 67 t and an EET of 06:02.

Now I insert the step climbs, and both the FUEL page and the F-PLN page show almost the same values as the SimBrief plan. So far, so good.

However, here is a procedure that causes a discrepancy: if, in addition to the step climbs, I also enter an estimated time of departure in the flight plan and then insert both into the plan at the same time, the FUEL page suddenly shows a trip fuel of 72 t and an EET of 07:22. That's suddenly 80 minutes more flight time. Strangely, the F-PLN footer correspondingly shows insufficient arrival fuel, but the EET there still works out to just over 6 hours.

If the step climbs and the estimated time of departure are inserted separately, i.e. not in a single step, the problem doesn't occur, or at least it didn't in my case (tested only once so far).

Another anomaly: this time I only inserted step climbs into the flight plan. The FUEL/PAYLOAD page showed the correct EET of 10:12, but the trip fuel was far too high (10 t more than in the SimBrief flight plan), so I got the DEST EFOB warning. When I then entered the estimated time of departure in the flight plan, the excessive trip fuel suddenly made sense, because the EET jumped to 11:30! So again roughly 80 minutes more than in the flight plan. On the F-PLN page, the EET stayed at 10:12 the whole time.

Hope this helps the iniBuilds team track down the issue!

On 10/3/2026 at 1:52 PM, Stevenssqueeze said:

Yesterday on a 8 hours flight the official ini Simbrief file for the RR engine variant was surprisingly pretty accurate. I landed with a 200 kg difference to the Simbrief plan.

Today on the 8 hour return flight with the same Simbrief file I have a gain of over 5 tons after 3 hours of flight!

So I try to understand why there is such a big spread with the same ini Simbrief file.

Can it be, that it has something to do with loading the aircraft? On my flight yesterday it seemed that the weight of the aircraft was pretty accurate, which led to a accurate fuel consumption during the flight.

Today it looks like, I am flying an empty A380, otherwise I cannot understand why I gain fuel this significantly.

So I would like to describe how I load the aircraft and maybe I do something wrong there.

1. After loading the aircraft I load the Simbrief plan via the EFB Flight Info.

2. Thereafter I click Ground Operations in the EFB and click the "Import Simbrief" button. A green confirmation comes up at the top of the screen.

3. I load the Flightplan via the INIT page of the MFD

4. On the OIS FLT OPS page I click SYNCHRO AVIONICS and check that the FLT NBR and Departure and Arrival airports correspond to my Simbrief Flight plan.

5. On the NSS AVINCS page I click INI COM and enter the FUEL FIGURES and send it.

6. I refuel the aircraft using GSX and I also refill the water and do the boarding with GSX.

7. On the OIS INI COM page I check the values on the Prelimenary Loadsheet and enter the ZFW and ZFWCG into the FUEL LOAD page in the MFD.

8. When refueling and loading of the passengers is completed I check the values in the Ground Operations Weight & Balance page ot the EFB. The figures of Passengers, Cargo, Fuel and Water in the column Planned and Loaded should be the same.

9. Then I finally check the Final Loadsheet figures and compare it with the entered values of the prelimenary loadsheet in the MFD. The values for the ZFWCG and the T/O CG are mostly different, so I enter the CG's of the final Loadsheet into the MFD T/O PERF page.

10. I start the flight.

Is there something wrong? I cannot really check, what my actual weight is. The values of GW and GWCG are a result of the entered ZFW and ZFWCG plus Fuel.

But where can I physically confirm, what the loaded weight is in my simulator. The only explanation of this immense fuel gain over time is for me, that the GSX loaded values will be confirmed by the EFB, but they are not physically loaded into the aircraft.

I could get an idea about my weight in flight when I check the pitch and the Green dot and the VLS on the PFD together with the current fuel flow. But I don't have performance charts for that.

Maybe we can collect the different ways to load the aircraft to get a clue, what the problem with these discrepancies in the fuel consumption compared to the Simbrief file is.

Thank you!

Maybe I got a little closer to the issue.

On my flight today I prepared the aircraft exactly as I described above. After I finished loading with GSX, I opened the GROUND OPERATIONS Weight & Balance page in the EFB and checked all the loaded values. It was all correct. The planned load was the same than the loaded values.

Then I clicked the green LOAD ARCRAFT button on the lower right corner and loaded again the Payload and Fuel instantly. Nothing changed of course on the loading page, since the values were the same, but I had the idea, if GSX is loading the aircraft correctly, maybe the load is not really physically loaded to the aircraft what would explain, why I don't burn fuel like in the Simbrief file and gain up to 10 tons of fuel on a longhaul flight.

With hitting the LOAD AIRCRAFT button and load again the values via the EFB and not GSX makes the difference. The Simbrief file was pretty accurate throughout the flight and ended up with a 1000 kg loss at the destination after a 09:10 hours flight.

I only tested it once, but I will report on the next flight.

1 hour ago, Stevenssqueeze said:

Maybe I got a little closer to the issue.

On my flight today I prepared the aircraft exactly as I described above. After I finished loading with GSX, I opened the GROUND OPERATIONS Weight & Balance page in the EFB and checked all the loaded values. It was all correct. The planned load was the same than the loaded values.

Then I clicked the green LOAD ARCRAFT button on the lower right corner and loaded again the Payload and Fuel instantly. Nothing changed of course on the loading page, since the values were the same, but I had the idea, if GSX is loading the aircraft correctly, maybe the load is not really physically loaded to the aircraft what would explain, why I don't burn fuel like in the Simbrief file and gain up to 10 tons of fuel on a longhaul flight.

With hitting the LOAD AIRCRAFT button and load again the values via the EFB and not GSX makes the difference. The Simbrief file was pretty accurate throughout the flight and ended up with a 1000 kg loss at the destination after a 09:10 hours flight.

I only tested it once, but I will report on the next flight.

I am having fuel issues even when I load through EFB. Start with say 12T EFOB at destination airport but land with 30 plus.

Ok. My thought was, that it might have something to do with loading the aircraft, since fuel is not consistent. On my last flight I had a fuel loss, the leg before a massi massive fuel gain.

If the Simbrief file is wrong, it should be always about the same tendency.

I will test it further and will report.

CI200: Weight confirmed with Simvarwatcher. Runway change and shortcuts on arrival. TAS was sometimes up to 10kts higher than planned.

	Plan	Sim	Δ
Trip fuel (takeoff → touchdown)	148,661	138,625	−10,036 (−6.8%)
Landing fuel	16,706	26,230	+9,524
Airborne time	11:08:35	10:51:40	−17 min
Taxi-out (APU + start + taxi)	1,089	~1,600	+500