A32NX custom FBW Incorrect weights

Trying to identify the issue with W/B numbers. I am using latest dev version of Simbrief.
ZFW in MCDU and OFP when it is generated is off by at least 2000 lbs or more.

Below is an example:

ZFW in MCDU is correct, however it is off in OFP. TOW in MCDU is different than in OFP as well. What I see Simbrief does not calculate ZFW correctly based on OEW etc.

Thanks for looking.

Hi, on your OFP, it has the following dispatch remark:


In order to not exceed the aircraft’s max landing weight at destination, it isn’t possible to take on 170 passengers weighing 230 lbs each (assuming 175 for the passenger and 55 for their bags, as SimBrief normally does). SimBrief won’t offload the extra 30 minutes of fuel you requested, since it is assumed that you had a good reason to need it, so it has to offload payload instead to make the numbers fit.

It seems like FlyByWire is simply loading the passenger count from SimBrief, multiplying it by 230, and adding that to the OEW. But in cases where the payload is arbitrarily limited by the MLW/MZFW/MTOW, this will create discrepancies as you have seen.

For this reason, the recommended way for FlyByWire to program their SimBrief import would be to directly import the ZFW number itself (rather than the passenger count number). If their load editor doesn’t support entering the ZFW directly, they might need to do some math in the back-end to calculate exactly how many passengers should be entered to result in the desired ZFW. Unless there is an “average passenger weight” that they can adjust instead.

Tanks for the reply. I see there is L code next to TOW. I was told FWB did not implement loading the way it supposed to. One of the developer said they were working on another airframe to allow cargo load and better load handling. Will see. Thanks again.

This topic was automatically closed 2 days after the last reply. New replies are no longer allowed.