I seen picutres of a Sentinal tank with an external fuel tank. The questions I have are in WWII did they use external fuel tanks on teh sentinal? If so could they and would they take it off when entering combat? If so could you assume the Russians had similair approach with external fuel tanks on their tank? Edit: http://www.armourinfocus.co.uk/sentinel/index.htm added link to the place I seen the pic.