Many moons ago we chartered the An-224 to carry 3 main-deck loaders into Baghdad. Each loader weighed around 30 tons, and were winched onto a platform and from there driven into the aircraft and chained down. All was good, until the loadmaster proclaimed they were 'slightly' out of balance, and required a bit of ballast to bring things back to where they should be. 'Not a problem' says I 'how much do you need?'. 'Around 30 tons should do it' came the answer, which saw my jaw dropping quite a substantial distance.
Amazing piece of kit.