I was going with the numbers in the article
I doubt a 100 ton airship would be able to lift several 63 ton tanks, at least not directly. The talk of "rapid acceleration" from their propulsion system sounds rather bogus, too. F = ma still applies to airships, so a big vehicle with a lot of mass still requires quite a bit of force to accelerate rapidly. Their propulsion scheme sounds like the aeronautical equivalent of the "caterpillar drive" on the Red October in Clancey's book. Only, air is only about 1/1000th as dense as water.