The performance build of Arma 3 crashes when saving with helicopter, this happens with and without the advanced flight model, both .exe and .dll are from the most recent 2.16 upload on Google Drive (at least as far as I could tell).

I tested in on the RF training day scenario where it initially happened both with and without AFM, then also tested it without any mods or DLC using the helicopter showcase. Crash happens regardless of flightmodel and with both manual and automatic saves.