you allways have to check the commited memory, not only the working set. You can do this with help of the Resources-Manager.
The commited size of MSFS is much higher : example Finally.....Solved CTD issues... for those of us with < 32 GB ram - #109 by MichaMMA
( 25gig working set, 35Gig commited )
a note: because you own only 16Gig RAM, you should not run other applications in parallel.
Normaly MSFS consume max about 32GIG, but at some places, the memory consume is much higher. But hmm… I expected a virtual memory setting of 32GIG fixed should realy be enough.