It may be pertinent to the discussion to note that Level D full flight simulators do NOT include sound cues for:
- Ice crystals (hail, yes, one size fits all generally, but smaller ice crystals no)
- Air impact cues from anything other than CAS/Mach related airspeed (i.e. any aircraft velocity that is not horizontal in nature will likely not cause any air impact noise cues.
So an aircraft dropping at 10,000ft/min vertically with at 0 knot CAS would be totally silent in the simulator....