Hmmmmm. Even the smell reminds me of an Armor Crewman FART in a closed tank after a night of heavy drinking, that would make me quickly hit the switch back of the TC hatch for the gas particulate system, and evac, to start sucking air blowing through a donkey dick, whether I was wearing a gas mask or not, though it is loud as hell. My driver, often kept his hatch cracked, as I couldn't see it from the cupola. I didn't complain about what I couldn't see from the cupola, particularly as it aided quick evac of foul air in the crew compartment.