external fuel tanks on tanks cannot be remotely demounted and they are used up first ( technically they refill the main tanks) . As for vulnerable , yes they are, but it does not matter , the positioning means any fuel will spill outside the tank onto the ground so even if it catches fire., it , at worse, just wreaks the external tank with no harm to the tank except a reduction in range.How vulnerable are rear mounted tank fuel drums? Can they be demounted or emptied in/for combat like an aircraft external fuel tank?
Has internal armour spalling been addressed enough yet? What can be done to reduce brew-ups and ammo cook-offs. Have the crews got a decent semi-auto carbine or machine pistol, if they have to evacuate the tank?