Originally Posted by
Sidestick_n_Rudder
Perhaps that’s why Airbus de-activated the FWD cargo hold on the -ULR model operates by SQ? As fuel capacity was increased, they might ran into FWD CG issues?
Also, there’s some anecdotal evidence of payload problems on the -350 on longer routes, ie. having to block seats and leaving bags/pad’s behind. Might it be C.G. issues as well?
I do not know SQ but as far as I know and what have I seen I'm pretty sure that is the problem.
I did not take a manual or any pictures of real flghts so it very illustrational just from what I remember. I found the envelope on the Internet and I would say that real one in more limited but the shape is correct. Especialy in FWD where it is most important for our case.
I made the green line which is fuel vector. You are at ZFW which is fine but once you take a lot of fuel it moves a bit AFT but then more and more fuel moves the CG very FWD and you hit the corner there. That is how one A350-900 flight looked yesterday. PAX almost full, cargo and bags loaded in AFT (it was full) and FWD hold was loaded too. Few rows for ULDs in FWD were empty. Not because they had to but they had nothing more to load.
But there are no doubts that more than weight you will have trim problems on this aircraft. When you take a lot of fuel you really have to be tail heavy at zero fuel weight.
